# Goin' Crackers.



## vlmarshall (Jun 6, 2009)

Shred's build of the Cracker (April's Project Of The Month winner) has convinced me to build my own. I haven't wanted to start a thread on it, mainly because of the craftsmanship standards that I see on here. :bow:
Still, here's my progress so far.
The first thing I had to do was come up with the gears, as the pitch diameter would set the axle and crankshaft spacing. I followed Shred's advice, and used RC pinion gears from Robinson Racing, as I've used their products many times in my younger days.

For a lot of this build, I'm "cheating" and using a CNC Sherline mill at home, and a manual Hardinge lathe at work. Cutting out the side frames was simple enough, and I decided to build TWO locomotives, one for myself, and one for my dad.

Here's the first one being cut out on my little Sherline at home.






This is too easy, so far.  The loco frames are 10mm longer, 5mm added to each end, to make room for a slightly longer boiler, and more room on the footplate as well. Originally I was going to add all 10mm to one end, and move the fuel tank under the footplate and between the frame rails, as I've read elsewhere online, but decided against it, at least for THIS build. ;D

I turned two sets of bushings, again diverting from the plans, and making all 8 bushings to the same dimensions. 
Here they are in place.


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## vlmarshall (Jun 6, 2009)

After reading a boiler post on here today, I wonder if I should have made my boiler end plates differently. The thread I saw today showed NO radius in the corner.
When I made my first set the radius I used was way too big...but at least it'll add extra water capacity. I'll use the big ends for the boiler backheads, but I turned a smaller radius on my mandrel, and made a second set.
Sorry for the blurry photo, the rest will be better. ;D


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## vlmarshall (Jun 6, 2009)

The wheels were fun, so I made an extra set. I enjoyed the two angles, and by setting the tool to cut one angle, and the compound slide to move along the other, these were quick and easy...especially since I turned them from 12L.





I added a .200" boss to the back side, so I could use 4-40 setscrews to secure them to the axle. The only place I want to use Locktite on these locos is between the crank throw and the crankshaft.


The frame end beams were easy, and mostly featureless for now, other than a few holes.


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## vlmarshall (Jun 6, 2009)

For the smokeboxes, I decided that using a pipe cap, with it's radius, would help give the Cracker a smaller, yard-loco appearance.

Here are both pipe caps, with a hole in one end for the smokebox doors.




They look more like engine cowlings for a radial. ;D


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## vlmarshall (Jun 6, 2009)

The pistons were easy enough, but I made them .375" instead of the plan's .3149".


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## vlmarshall (Jun 6, 2009)

Yesterday I made the cylinder backplates, and some quick-and-dirty banjo fittings, that need some more work before I'm happy with them.




Those giant hex nuts, and the locomotive's button-head Allen screws, are going to be really unpopular around here. ;D


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## Shopguy (Jun 6, 2009)

Looking good, coming along real nice.
Don't worry too much about the screw heads at this point, get the loco running, you can fancy up the fasteners later.
Regards
Ernie J.


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## shred (Jun 6, 2009)

Looks great... better than mine at the time ;D

My boiler plates have rounded corners, though not that much. I don't think it matters a lot at these sorts of pressures.  According to one place, you could even use flat disks of copper, though I'd rather have the silver solder contact area of flanged end plates.

As I read elsewhere "It's a little unfair to a tiny model to show a big photograph of it..." I found 2-56 button-head cap screws looked enough like rivets when viewed normal size that's what I mostly used.


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## tel (Jun 6, 2009)

Nice start! :bow: One of these days I'm going to 'crack' and build one meself.


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## itowbig (Jun 6, 2009)

alright nice work i want to build one for the wify. but its going to have to wait im not that good yet.
yours is looking real nice. thank you for showing us the build.


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## vlmarshall (Jun 11, 2009)

Thank you all for the encouraging comments, and Shred for the tips. The people here make an enjoyable project even more fun.
My newest progress is a few more pieces;
The boiler bushings, made from Phosphur Bronze...I made them all the same size instead of the plan's 10mm/8mm, tapping them all 5/16-24.





Cylinders for both machines... they're a bit bulky compared to some of the others I've seen. As I mentioned earlier, with the piston photo, I've enlarged the bore from the plan's .3125" up to .375". I just couldn't help myself. ;D




I wanted plenty of material at the contact face for future lapping, both of these locos are going to be runners, I'm planning for wear. I added brass bushings to the big-end of the pistons for the same reason.

...and a pair of flywheels. One of 'em is a day or two older than the other. ;D




I made them thicker than the plan (like everything else). I'm trying to get these engines to run as slowly as I can, and figured the extra mass couldn't hurt. Besides, the thicker flywheel offsets the look (and balance) of the cylinder hanging off the other side. ;D 


Once again, I'm really happy with my little Sherline mill.





Thanks again to everyone for the comments. This is fun, I should have started sooner. ;D :bow:


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## zeeprogrammer (Jun 11, 2009)

vlmarshall  said:
			
		

> This is fun, I should have started sooner.



I have had that thought every day since Feb 12 when I started this great hobby.

It is fun and I was fortunate (as you) to find this site.


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## vlmarshall (Jun 17, 2009)

:big: Test ran both engines on air today...no direct connection available, so I just used an airgun. One of them runs a LOT slower than the other, I've got more work to do. No new photos to post, yet.


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## zeeprogrammer (Jun 17, 2009)

A test run and no pics? What are you thinking?
Can't wait to see.


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## vlmarshall (Jun 17, 2009)

zeeprogrammer  said:
			
		

> A test run and no pics? What are you thinking?
> Can't wait to see.



I was at work! ;D Lunch break, using the only non-OSHA-compliant air nozzle in the place, fighting a coily air line, while trying to hold a loco frame without being eaten by gears. 

I'll post a VIDEO when I cobble together a better test setup. I know I have a low-pressure regulator around here somewhere...


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## zeeprogrammer (Jun 17, 2009)

vlmarshall  said:
			
		

> I was at work! ;D Lunch break, using the only non-OSHA-compliant air nozzle in the place, fighting a coily air line, while trying to hold a loco frame without being eaten by gears.



Oh hey I understand. Really I do.  I was just worried about what everyone else thought. Tough crowd here. (At work...yeah right.) :big:

Myself...I'm on HMEM nearly every day at lunch. Even when I'm Skyping with wife (don't no one tell her). Can't work on the engine though. She'd see me.


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## BMyers (Jun 21, 2009)

vlmarshall  said:
			
		

> The first thing I had to do was come up with the gears, as the pitch diameter would set the axle and crankshaft spacing. I followed Shred's advice, and used RC pinion gears from Robinson Racing, as I've used their products many times in my younger days.


Very Nice Job !

Does Robinson Racing have a web sight ? What are the P/N's of the gears ? This engine is on my list of projects.
First objective find a lathe to replace my monster P&W (see show off your lathe link)...


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## shred (Jun 21, 2009)

BMyers  said:
			
		

> Very Nice Job !
> 
> Does Robinson Racing have a web sight ? What are the P/N's of the gears ? This engine is on my list of projects.
> First objective find a lathe to replace my monster P&W (see show off your lathe link)...


These are what I used: http://www.robinsonracing.com/catalog/48pitchpinion.html
The smallest and largest the hobby store had in 48P-- 12T and 35T. I suspect that being off a tooth or two either direction won't hurt as long as you get the axles located correctly. Interestingly the combination I arrived at almost completely by random is very close to the "original" full size Byers locomotive.


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## vlmarshall (Jun 21, 2009)

BMyers  said:
			
		

> Very Nice Job !
> 
> Does Robinson Racing have a web sight ? What are the P/N's of the gears ? This engine is on my list of projects.
> First objective find a lathe to replace my monster P&W (see show off your lathe link)...



  I used the same Robinson link that Shred used, and bought 41 and 12-tooth gears, running them on .125" shafts cut from drill blank. Smooth and straight stuff. 
Anyway, I just meshed the gears and measured the spacing, although some people might find Marv Klotz's "GearSpur" utility more useful. http://www.myvirtualnetwork.com/mklotz/

  As it was, I ended up running in the gears with lapping compound to get them free-running enough to spin over a few revolutions with a finger flip. I was going to check the profile on a comparator first, ( I suspect the profiles aren't exactly correct... it couldn't have been MY error. ;D : ) but I didn't get around to it before the lapping compound. 


Interesting PW lathe, that IS a monster. I really like the looks of that little South Bend you've got... the first lathe I ran was an old open-belt head like that, and I've had a soft spot for them ever since.

Thanks for the compliment on the Crackers! I hope to have a photo update soon, but the little things I've been doing lately aren't very interesting.

I do have a question for Shred; What is the ID of the steam lines you used? The stuff I have is mostly .062", although i have some thinwall K&S stuff that's .097". If I have to, I'll make a line of each size, and try them both.


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## shred (Jun 21, 2009)

vlmarshall  said:
			
		

> I used the same Robinson link that Shred used, and bought 41 and 12-tooth gears, running them on .125" shafts cut from drill blank. Smooth and straight stuff.
> Anyway, I just meshed the gears and measured the spacing, although some people might find Marv Klotz's "GearSpur" utility more useful. http://www.myvirtualnetwork.com/mklotz/
> 
> As it was, I ended up running in the gears with lapping compound to get them free-running enough to spin over a few revolutions with a finger flip. I was going to check the profile on a comparator first, ( I suspect the profiles aren't exactly correct... it couldn't have been MY error. ;D : ) but I didn't get around to it before the lapping compound.


I ran into a problem where I didn't leave enough play in the gear train when laying it out. I doubt these little guys are perfectly to spec either. Highly recommend computing the correct axle spacing.


> I do have a question for Shred; What is the ID of the steam lines you used? The stuff I have is mostly .062", although i have some thinwall K&S stuff that's .097". If I have to, I'll make a line of each size, and try them both.


I don't remember the IDs. It was K&S copper tubing, and a quick slap with the calipers on the steam-dome-to-engine line shows it to be 3/32" OD, with the exhaust from engine-to-stack being 1/8" OD-- performance improved with the larger exhaust pipe but I never tried larger on the incoming line-- the engine port sizes will limit flow, so I'd guess anything somewhat larger than the ports will be ok.

[update: the 3/32" stuff appears to be pretty close to 1/16" ID, and the 1/8" is probably close to 3/32" ID]


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## mklotz (Jun 21, 2009)

For spur gears, the correct center-to-center spacing is given by the average of the pitch diameters of the two gears.

(Spur) gears can be thought of as two cylinders (of respective pitch diamters) in rolling contact with teeth added to (the gear addendum) and subtracted from (the gear dedendum) to prevent slipping. The spacing between the two cylinders is of course the sum of half the diameter of each cylinder = the average of the diameters.


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## vlmarshall (Jun 21, 2009)

Thanks, Shred. Great to know I'm not too far off.

Marv, thanks for that giant collection of applications. Your gear calc gave numbers within .002" of what I used. :bow:


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## BMyers (Jun 21, 2009)

vlmarshall  said:
			
		

> Interesting PW lathe, that IS a monster. I really like the looks of that little South Bend you've got... the first lathe I ran was an old open-belt head like that, and I've had a soft spot for them ever since.



Not to hijack the thread; the PW is a great lathe, it now belongs to someone else. I am downsizing to machines easier to move in anticipation of relocating to chase work ( I have been unemployed since Feb). The South Bend is a 1928 22A jr. I really like it, does nice work and will stay with me. I want to compliment it with a 9 or 10" lathe with a GQ gear box and power cross feed. 
Now, back to the regularly scheduled posting.
Thanks for the info on the gears, I will file that away for when I build mine


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## vlmarshall (Jun 21, 2009)

BMyers  said:
			
		

> ...The South Bend is a 1928 22A jr. I really like it, does nice work and will stay with me. I want to compliment it with a 9 or 10" lathe with a GQ gear box and power cross feed...



Nice little lathe, I really like it. No worries about hijacking my thread, I ramble off-topic in other people's posts all the time, I wouldn't expeect any different in my own, and besides, it'd get boring if it was ALL Cracker here.

Speaking of boring, I finally got around to cutting chimney holes in the smokeboxes, and have decided to try an alternate part, cutting the smokebox out of a slip coupler like Shred and everyone else. I have a pair of them here, so they went into the mill after the rounded ones.











It's been a few days since I've posted a new photo, so I had to show _something._ ;D


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## vlmarshall (Jun 22, 2009)

I'll even post a link to a not-so-exciting video of the smokebox cutting. ;D
[ame]http://www.youtube.com/watch?v=rTfshaaOQsE[/ame]


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## zeeprogrammer (Jun 22, 2009)

I watched the entire 4.24 minutes.
But maybe I'm just trying to make you think you made a good offer? (The guinness...remember? I do.) 
But really...I like watching videos of machining operations.
Thanks.

What was that noise at the very end? It sounded like a kid?


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## vlmarshall (Jun 22, 2009)

zeeprogrammer  said:
			
		

> I watched the entire 4.24 minutes.
> But maybe I'm just trying to make you think you made a good offer? (The guinness...remember? I do.)
> But really...I like watching videos of machining operations.
> Thanks.
> ...


Yep, that was my 4-yr-old daughter asking, :Hey dad, can I talk now?" ;D I'd asked her to be quiet while I made a movie. 
Guinness? What Guinness, I don't remember any offer. :big: ;D :big:


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## vlmarshall (Jun 22, 2009)

This evening I punched fiber gaskets for my steam line banjo fittings, laid out the bushing holes on the boilers, Loctited the crank throws onto the crankshafts, trued up the alternate smokeboxes, deburred them, removed the stop lugs so they'd press onto the boiler tube, and still managed to spend all evening on here. How?
Resource management. ;D


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## zeeprogrammer (Jun 22, 2009)

And all I managed to do is mount a chuck on a RT on a mill. That and a little more ranting. Could've used the Guinness.

I didn't know you were that young. And blonde too. ;D

Isn't it a joy?

I hope you don't mind my intrusion...put a cap on that head...even if the machines aren't running...have her develop the habit.


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## vlmarshall (Jun 22, 2009)

zeeprogrammer  said:
			
		

> And all I managed to do is mount a chuck on a RT on a mill. That and a little more ranting. Could've used the Guinness.
> 
> I didn't know you were that young. And blonde too. ;D
> 
> ...


Ha, I saw your rotary table post, and I'm glad for it. Nice little table. Chuck's kinda tall though.

Nope, I'm not that young, or blonde. I'm lucky, both her and her mom are interested in this kinda stuff. A cap or at least a hair tie's a good idea... she's even wearing one on her wrist like I do when my (too long) hair's not tied back. Good idea to start safe, young. Thanks, Zeep. ;D


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## vlmarshall (Jul 1, 2009)

Well, I cut the bushing holes in the boilers yesterday. Straightforward, quick and easy.


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## zeeprogrammer (Jul 1, 2009)

Post 15? stickpoke

Where do you get the copper from?


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## vlmarshall (Jul 1, 2009)

The big tubing, 1.375" OD, 1.250"ID, came from some plumbing service place, where my dad knows someone working there. ;D
The small-diameter stuff came from Lowes... nothing special about that one. Sold as 1/2" tubing, ( or pipe, whatever, I'm no plumber) it measures .625" OD and .555" ID. Go figure. ???
The end caps are cut from the big tube and hammered to shape over a mandrel.
The little bushings are turned from some Phosphur Bronze that came from Mcmaster-Carr.

Today I silver-soldered the whole works together... my first attempt at silver-soldering. Luckily we have a good set-up at work... it didn't go too badly. ;D





I see a few pinholes around the bushings... I wonder if they'll leak.


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## zeeprogrammer (Jul 1, 2009)

1st attempt! That must have been exciting.
I see a lot of references to silver soldering on this forum.
I know I'll have to have a go at it some time.

Did you see 'firebird's setup for testing his boiler and pressure? I want to build the little pump he made.


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## vlmarshall (Jul 1, 2009)

zeeprogrammer  said:
			
		

> 1st attempt! That must have been exciting.
> I see a lot of references to silver soldering on this forum.
> I know I'll have to have a go at it some time.
> 
> Did you see 'firebird's setup for testing his boiler and pressure? I want to build the little pump he made.


Man, it was.. I didn't know if I'd melt it into a blob, or what. Although, I can braze, stick weld, MIG, and TIG with reasonable skill, I'd never tried this stuff, or anything with copper, other than soldering.

I wanna build that little pump too.... I need it, now. ;D


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## zeeprogrammer (Jul 1, 2009)

Vernon  said:
			
		

> other than soldering.



Which is the sum total of my experience melting anything other than toy plastic soldiers.


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## shred (Jul 1, 2009)

FWIW, there's a slightly-easier-to-build piston pump stashed in my Slightly Loco thread. It works ok, but the lever kind like Firebird's isn't much more work and probably a lot more controllable.


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## vlmarshall (Jul 1, 2009)

zeeprogrammer  said:
			
		

> Which is the sum total of my experience melting anything other than toy plastic soldiers.


Yeah, you can solder... this wasn't much different. Cleanliness and flux are the secrets, just like soldering. 



			
				shred  said:
			
		

> FWIW, there's a slightly-easier-to-build piston pump stashed in my Slightly Loco thread. It works ok, but the lever kind like Firebird's isn't much more work and probably a lot more controllable.


Thanks, Shred, I'll go look for it. I bet I've already saved a picture, or Crap-o-cad, of your pump...along with everything else in your thread. ;D


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## vlmarshall (Jul 12, 2009)

Well, I made the saddle mounts for the boilers yesterday, out of some pressed-mica block. The stuff is a bit abrasive, but not too hard to machine to machine, but if you try to drill it with the 'grain', it'll split easily.

I'll add some pictures here eventually.
The front block is drilled straight through, with a bolt through it from the smokebox, threaded into the front frame crossmember.
The rear block is just a saddle bolted to the footplate, with a counterbore for bolt head clearance under the boiler.


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## zeeprogrammer (Jul 12, 2009)

Very cool! :bow:



Hey! What are you doing over here? I need your help. :big:


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## shred (Jul 12, 2009)

Looks great! It's always really cool when they run on real steam.

You've gotta rig yourself a pressure gauge so you can see what's up when testing the safety and burner tuning-- doesn't have to be a little one, mine was a surpluscenter 200 PSI model, same as available at hardware stores for $15-20. there's not a pic of it in my thread except on the pump, but it's featured in the safety-test video- http://www.homemodelenginemachinist.com/index.php?action=dlattach;topic=2049.0;attach=1603 the pigtail pipe is to prevent live steam from damaging the works-- a U-bend would probably work as well.


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## vlmarshall (Jul 12, 2009)

zeeprogrammer  said:
			
		

> Very cool! :bow:
> Hey! What are you doing over here? I need your help. :big:


Doing here? I figured I'd pollute my own thread with senseless ramblings for a change. ;D



			
				shred  said:
			
		

> Looks great! It's always really cool when they run on real steam.
> 
> You've gotta rig yourself a pressure gauge so you can see what's up when testing the safety and burner tuning-- doesn't have to be a little one, mine was a surpluscenter 200 PSI model, same as available at hardware stores for $15-20. there's not a pic of it in my thread except on the pump, but it's featured in the safety-test video- http://www.homemodelenginemachinist.com/index.php?action=dlattach;topic=2049.0;attach=1603 the pigtail pipe is to prevent live steam from damaging the works-- a U-bend would probably work as well.




Thanks, Shred.
I've got a gauge set aside, I guess I'll turn a fitting tomorrow. I really should build a test pump.


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## shred (Jul 12, 2009)

FWIW, on the original 'Cracker' design, there is no 'safety valve' per-se. The spring and oscillator mechanism provided that. Personally I wanted a more positive safety, so I added one, but it never comes close to 30 PSI when the motor is running.


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## BMyers (Jul 12, 2009)

very nice !
I have a question for those who have built the Cracker. Never building a steamer I don't see from the drawings how the steam gets into the engine and condensate leaves. I guess the drill jig for "ports" has something to do with that. But I dont see ports on the drawings. 
Some pictures and advice would be appreciated because I think I am going to build the cracker, I need a reason to try out my new 10" Logan


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## vlmarshall (Jul 12, 2009)

shred  said:
			
		

> FWIW, on the original 'Cracker' design, there is no 'safety valve' per-se. The spring and oscillator mechanism provided that. Personally I wanted a more positive safety, so I added one, but it never comes close to 30 PSI when the motor is running.


Thanks, Shred.




			
				BMyers  said:
			
		

> very nice !
> I have a question for those who have built the Cracker. Never building a steamer I don't see from the drawings how the steam gets into the engine and condensate leaves. I guess the drill jig for "ports" has something to do with that. But I dont see ports on the drawings.


Yeah, they don't actually SHOW the ports on the drawing, just a little drilling jig that you're supposed to build and drop over the assembled engine backplate and crankshaft. the top hole will line up with the correct drilling location at either end of the cylinder's swing.
I just sharpened one end of a small piece of drill rod, cut it to a length that would sit in the cylinder, barely sticking out of it's port. Then I rounded the opposite end, , left the pivot's spring off, and pressed the cylinder into the backing plate at each end of it's swing, marking the drill locations.


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## vlmarshall (Jul 14, 2009)

Well, I turned up that test fitting, and plumbed a pressure gauge, and a diaphragm pump into the boilers.
I'd forgotten I had a 12v sprayer pump laying around, with a 60psi cutoff switch on it.

Still, I managed to peg the needle on on the 60psi gauge I dug up... and the pump leaks down to 45psi after 20 minutes or so, leaving me with a puddle of water, but I'm still grinning.

It's good to be another step closer to completion.


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## zeeprogrammer (Jul 14, 2009)

Most excellent.


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## vlmarshall (Jul 14, 2009)

It's alive! Test ran the second Cracker today, Chassis #1 actually, the one for my dad. I'm trying several burner sizes, so this run was on my Weller handheld soldering iron with torch tip.
[ame]http://www.youtube.com/watch?v=uakRJp4p7-M[/ame]

It's blurry, I keep forgetting the camera doesn't have Macro mode when shooting video. ;D


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## rake60 (Jul 14, 2009)

Looking Great Vernon! Thm:

Beautiful Craftsmanship!

Rick


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## shred (Jul 14, 2009)

Looks good. What boiler pressure was the Weller able to make?


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## vlmarshall (Jul 14, 2009)

Thanks Rick! It'll never compete with the stuff on here.



			
				shred  said:
			
		

> Looks good. What boiler pressure was the Weller able to make?


Not much pressure, wet exhaust... I don't know exactly, I sprung my gauge when I overpressurized it. It reads 7psi at zero, and was showing around 15 when running...but I wouldn't trust it to be a simple math solution. It's trash now.

No matter, the gauge was something I had left over from a coolant filter project, else I'd have used something with a larger range.


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## vlmarshall (Jul 14, 2009)

I'll try again whith a real gauge, when I have the safety valves started.

Has anyone ever added a whistle to the top of a safety valve?


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## shred (Jul 15, 2009)

Vernon  said:
			
		

> I'll try again whith a real gauge, when I have the safety valves started.
> 
> Has anyone ever added a whistle to the top of a safety valve?


I considered it (I thought it would be kinda cool to have the safety blow through a whistle), but unless you make it big, it'll be very shrill and maybe not even audible-- The Gauge-1 train folks usually have a large whistle hidden underneath somewhere and a fake one on top.


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## vlmarshall (Jul 15, 2009)

shred  said:
			
		

> ...unless you make it big, it'll be very shrill and maybe not even audible...


Yeah, that's what I thought. I've seen the hidden whistles (man, they sound nice), and as much as I'd like to have a big ol' multichime tucked under there, the idea of running my safety valve through a long tube doesn't appeal to me.

Still, the whistle on my old Wilesco engine is a 30mm long piece of 5mm OD tubing, and it's not TOO bad. I'm going to try it. I even drew it up with a remote release lever.

Worst-case, I have an odd-sounding valve, and I won't tell anyone it's supposed to be a whistle. ;D

I see why you ran your loco so much during construction, these things are a lot of fun.


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## BMyers (Jul 15, 2009)

Very Cool !

Has anyone ever TIG welded a copper boiler ?


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## vlmarshall (Jul 18, 2009)

BMyers  said:
			
		

> Very Cool !
> 
> Has anyone ever TIG welded a copper boiler ?



A quick search online says "yes". I didn't try it with mine, My TIG skills in aluminum need help, and I imagine copper welds much the same way.

Yesterday, I rebored the cylinder for Cracker #2, removing a mark in the bore I didn't like, and giving me a reason to make a new piston. (bigger, and stainless) The first set of pistons were drill rod. I didn't oil one after a test run, and that was it; rust and pitting. I knew better. :-\

Other than that, no physical progress... just burner testing and planning, cab layout, and time spent drawing up a smokebox cover.


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## BMyers (Jul 18, 2009)

I have tig welded a little copper. DC current, but it takes a lot of heat to get a puddle then you have to back off. I may practice on some scrap and see what happens. I did silver solder the crank on mine today and was happy with the results.


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## BMyers (Jul 18, 2009)

Hey Vernon,
How about some pics of the banjo fittings and screws. How did you make those ?


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## vlmarshall (Jul 18, 2009)

BMyers  said:
			
		

> Hey Vernon,
> How about some pics of the banjo fittings and screws. How did you make those ?


Sure thing! They're nothing special, at all.

The steam dome fittings, ( the larger in the pic.) are 5/16-24 thread, turned from brass stock, with a lot of extra material left at the head, because I may drill and tap them for either a relief valve, or a filler. (Or, I'll toss these, and make something more suitable.)
The ring portion of the banjo is just a chunk of Phosphur Bronze, turned and drilled. I used one of them for the temporary test line, and since I've read that you can't silver-solder over ANY soft solder, I won't even try cleaning that one, I'll just make another. I'll probably add a groove around the inside at the same time.

The inlet and exhaust port fittings are crap, just a drilled and turned piece of 8-32 bolt, some turned brass rings, and a couple of nuts that absolutely refuse to seal, always leaking around the threads. The next attempt will use either a cap nut, a bolt, or a straight compression fitting, if only I could find a supplier for something that small. 
I don't want any of the lines to be permanently attached at either end; like I said in an earlier post, I'm planning for future maintenance.
Here's a shot of the fittings. Left to right, two leaky bolts, next time, stainless. two brass fittings, one soldered to a test line, a phosphur bronze steam dome fitting, and two steam dome banjo bolts.




Here's a shot of the inlet port. Nothing special here, other than the clearance notches I had to cut in the cylinder to clear the banjo fittings.
Also visible are the setscrew holding my pivot bolt in place, and the mica-block boiler saddles. The rear saddle bolts to the footplate, the front is captured between the smokebox and the footplate by a through-bolt.


----------



## BMyers (Jul 18, 2009)

thanks Vernon,
I went 4-40 on the ports, figuring that was pretty close to M3. Hope I dont regret the decision


----------



## shred (Jul 18, 2009)

I've got some sealing issues around the engine steam lines on mine as well-- some paper gasket material and sealer helps, but I think there's just too many sliding bits to really be a good joint. The easy answer might be soft soldering and just desoldering it for disassmbly, but I don't like that much and think if I were to do it again I'd try making a small compression fitting. Kozo's New Shay book has some instructions on making compression fittings in the back that look fairly simple to fab.

Btw, the exhaust on mine is kind of a trick-- there's no sealing needed and the 'drilled bolt' is long enough internally that it can be unscrewed and slid up the pipe to the smokebox far enough to clear the threads and remove that pipe without pulling any of the other engine bits.


----------



## vlmarshall (Jul 18, 2009)

shred  said:
			
		

> The easy answer might be soft soldering and just desoldering it for disassmbly



Thanks, Shred, good point. Desoldering wouldn't be that hard, and the two soft-soldered joints have held up so far. I'll add it to the list of considerations.


----------



## vlmarshall (Jul 19, 2009)

Must...resist...<a href="http://www.homemodelenginemachinist.com/index.php?topic=5485.msg57843#msg57843">Projectitus</a>...

Ha, that little rocker engine looks fun, it's hard to resist. However, I'm terrible for switching projects halfway through... even a coworker/friend of mine who buys a different car/truck/Harley every year is laughing at me.

So, I must distract myself from the tiny engine builds somehow...

Cardboard cutouts! ;D I've started on the mockups for the bodywork. After I decide what body style I want, I'll draw up REAL patterns with the same software I use for my cardstock models. 







 ;D My wife accused me of playing with paper dolls when she saw my 96mm assistant, "Chip". He's a 16mm-to-the-foot scale 6-foot human, added in for a better sense of scale.






I'll be trying a few variations, differently-shaped windows and door cutouts, smaller tanks, a saddle tank, and if I don't make the front left water tank a fuel tank, I'll be adding a coal bunker to the rear of the cab.











Yeah, I know it's silly. I've already used up my 40 hours of "serious" for this week. ;D


----------



## bearcar1 (Jul 19, 2009)

Now if we can just get you to color staying inside the lines, you'll be fine! Rof} A terribly good idea using the cardboard mock ups, I sometimes have a hard time visualizing what the end results will be in my head. So many options to go with in detailing these engines, it's amazing, who would have thought it. Chip appears to be enjoying himself way too much. ;D

BC1
Jim


----------



## zeeprogrammer (Jul 19, 2009)

bearcar1  said:
			
		

> Now if we can just get you to color staying inside the lines, you'll be fine!



Vernon doesn't strike me as the type. In fact, too often, when someone draws a character, it's their own inner being that comes out. Look closely at Chip. I'm thinking he's mischief maker. Coloring outside the lines would be in character.

I like prototypes and mock-ups. They are very handy.

Oh...and draw a girlfriend for Chip. Rof}.


----------



## BMyers (Jul 19, 2009)

Very Cool !!! :bow:


----------



## shred (Jul 19, 2009)

Cool. I hacked out a paper cutout for the cab on my loco, but it wasn't near as nice as these.


----------



## vlmarshall (Jul 19, 2009)

Haha, thanks, everyone! I didn't really expect a response , I'll probably be posting more photos as I tweak the cardboard cutouts... not as fast as Crap-O-CAD, or as nice as Rapid Prototyping... I guess I'll call it Ragged Prototyping.

Actually, posting the pictures on here and then coming back to them later, I've seen a few things I don't like. Changes will follow...feel free to become bored and run away. 



			
				zeeprogrammer  said:
			
		

> Vernon doesn't strike me as the type. In fact, too often, when someone draws a character, it's their own inner being that comes out. Look closely at Chip. I'm thinking he's mischief maker. Coloring outside the lines would be in character.
> 
> Oh...and draw a girlfriend for Chip. Rof}.



Hahaha, I have no idea what you're talking about. ;D
Also...draw a girlfriend for Chip? My wife predicted I'd be making clothes for him next...


----------



## Maryak (Jul 20, 2009)

Vernon,

No only is your Cracker choo choo nice, so is your sense of humour.  :bow: :bow:

Best Regards
Bob


----------



## bearcar1 (Jul 20, 2009)

Say Vernon, I notice that round the lip of the chimney flue saddle and at its base, there appears to be a series of dimples. It gives the appearance of a rivet line, how did you achieve those ???


BC1
Jim


----------



## vlmarshall (Jul 20, 2009)

Maryak  said:
			
		

> No only is your Cracker choo choo nice, so is your sense of humour.



Thanks! I like to unwind when I'm at home working on this stuff. ;D



			
				bearcar1  said:
			
		

> Say Vernon, I notice that round the lip of the chimney flue saddle and at its base, there appears to be a series of dimples. It gives the appearance of a rivet line, how did you achieve those ???


I just punched a row of dents from the back side, with a punch ground to about .030" or so, and radiused. Sitting against the smooth, polished surface of a V-block, the outside of the bump is flattened into what you see. Not the most realistic rivet bumps, but it'll hopefully add texture under paint and at least hint at rivets.

 I like the "baling wire and bubblegum" maintenance you see on old narrow-gauge railways, so my sloppy row of rivets has a purpose. ;D
There's actually another row around the smokebox where it meets the boiler.they don't show up well at all, since the material is a lot thicker, but it's not exactly authentic, so I didn't press the issue.


----------



## bearcar1 (Jul 20, 2009)

Oh I like the faux rivet effect a lot. I never noticed they were out of line at all. Anything that adds just a touch of the real thing is always better than straight, clean lines at times anyway. Your loco is going to be terrific looking. I can't wait to see what you finally decided on as far as saddle tanks etc. It'll be great!

BC1
Jim


----------



## vlmarshall (Jul 20, 2009)

Thanks!



			
				bearcar1  said:
			
		

> I can't wait to see what you finally decided on as far as saddle tanks etc.



I can't either.. and I'm not working on it tonight, I have homework! The bottom pair of parts in this picture, which still need to be finished:





A pair of replacement sears, work for a friend of the boss. ;D


----------



## BMyers (Jul 20, 2009)

Hey Vernon,
what holds the boiler in the saddles ?


----------



## vlmarshall (Jul 20, 2009)

BMyers  said:
			
		

> Hey Vernon,
> what holds the boiler in the saddles ?


At the front, a bolt through the smokebox portion of the boiler tube, or in my case, seperate smokebox tube.
At the rear, nothing. It just rests on the rear saddle, allowing for thermal expansion.

At first, I considered using the cut-off portion of the coupler I made smokeboxes out of, to make a ring bolted down like the front. I may still do that, opening up the radius in the rear saddle for the larger diameter tube, but it seems like the steam line and burner will do a good job of securing the boiler on their own.

If not, I can always do a little rework.


----------



## vlmarshall (Jul 21, 2009)

Crap.

Made a part for Zeep's "Wall Of ShameTM" today... a Goodall valve with a through-hole. :-\
Also tried a few safety valve/whistle ideas, to no avail...yet.

That's what I get for deciding to stay late at work and make a few parts, with no plan. :

On the good side, I've got some silicone tubing for fuel line, I've realized the compression fittings I've been looking for are easier to just make, and I seem to have found a tap for the fill valves from the Harbor Freight pen torches.

I'll try again tomorrow.


----------



## zeeprogrammer (Jul 21, 2009)

Whoa! It's your part...it's your 'Wall of Shame'! I'm very proud of my 'Wall of Shame' and you should be of yours. Otherwise, you're going to have to give me credit for the good stuff too. Oh...I see...sorry.

Crap indeed.


----------



## shred (Jul 21, 2009)

I was poking around the internet today looking for something else but ran across this in a set of articles: http://www.gauge0guild.com/manualonline2.aspx In the Live Steam section on Small Repairs (the rest are worth a read as well) is a bit on making compression fittings for tube as small as 1/16" OD. It should be possible to sub #4-40 for 6BA in that size and scale up as needed to Cracker-sizes.


----------



## vlmarshall (Jul 22, 2009)

Thanks for the link, Shred, I just might use those flare fittings. Those are good articles, entertaining to read during lunch today.

At least, when I wasn't making a .375" dent in a chunk of 4140...




I made a punch and die, with .625 round stock, and a .750" ballmill, to bash small pipe caps into domes. One of these will be the steam dome cover for Loco #1, which will be an O-scale Cracker-like loco for my dad.

On loco #2, (mine) this will be a smaller dome cover over the Goodall valve in the front boiler port, and won't have a cutout for a steam line. 
I guess I'll put rivet bumps on it, too.
Edit: Oops, I forgot rivet bumps. I got ahead of myself and silver-soldered the copper ring to the inside of the dome without punching the rivets. That dome REALLY needs some kind of detail, at least a flare at the bottom... I might remake it.







These valves really work! I haven't tried it under steam yet, but I know it seals... pushing Loco #2 backwards pressurizes the boiler, which I've already played with long enough to flip the engine over a rev or two. ;D

 I wanted to try the first one before I made two. Well, three, really, if you count yesterday's mistake. ;D


----------



## vlmarshall (Jul 24, 2009)

Not much progress today.

Made another little dome, this one for "my" Loco, no polished finish, and no steam line cutout, this will cover the fill valve in the forward port. I probably I made the boiler ports too close to each other to use the large dome... I think Shred mentioned moving the fittings further apart in his thread, too. Oops. Maybe I can make it look good anyway.

Also, I tried the oven-blackening of the extra 12L14 wheelset, they didn't come out much darker than with the chemical tool black, but the finish does seem more durable, so I added a white stripe, and I'll "test fit" them later to see if I like the look.






Lastly, I started on the burners. Sort of a combination of the tube burner Shred drew up, and a drilled stainless burner I found online somewhere. I used stainless tube and a staggered hole pattern, and I'll make the tube and holder to Shred's dimensions. 
I hope it works. Right now they have no air hole and are too long to burn properly... but they look neat, does that count for anything? ;D





I'll cut them to length later. 

 The plug in the end is a Stainless 5/16 socket head capscrew, threaded in about .250", with the head ground down to the bottom of the hex hole.


----------



## arnoldb (Jul 25, 2009)

Looking VERY nice Vernon!
Regards, Arnold


----------



## vlmarshall (Jul 25, 2009)

arnoldb  said:
			
		

> Looking VERY nice Vernon!
> Regards, Arnold


Thanks, I hope the tubing I used (.375") isn't too big. It sure seems like this style burner radiates a LOT more heat than an open, straight, flame... so, if it has enough room in the flue to burn, I'm going to be happy. ;D


----------



## BMyers (Jul 25, 2009)

Vernon,
very nice. you will have to post how that burner works and of course drawings for us who like to copy


----------



## Speedy (Jul 26, 2009)

great work!
with the punch, did you have to heat the part up befor hitting it?


----------



## arnoldb (Jul 26, 2009)

Vernon  said:
			
		

> Thanks, I hope the tubing I used (.375") isn't too big. It sure seems like this style burner radiates a LOT more heat than an open, straight, flame... so, if it has enough room in the flue to burn, I'm going to be happy. ;D



You're WAY ahead of me - I need to study up on burners etc. (Only burners I know are on my cooker- need those to get grub  )
From the looks of those burners, they should make a nice bunch of flames though 
Regards, Arnold


----------



## vlmarshall (Jul 26, 2009)

Speedy  said:
			
		

> with the punch, did you have to heat the part up befor hitting it?



No, I didn't even anneal the copper this time. Just tapped on them a bit, to raise the center, then filed away the name stamped into the top, and continued punching them into shape. Quick and easy. Any imperfections in the pocket will show up on the parts, so keep it smooth. ;D




			
				arnoldb  said:
			
		

> You're WAY ahead of me - I need to study up on burners etc. (Only burners I know are on my cooker- need those to get grub  )
> From the looks of those burners, they should make a nice bunch of flames though
> Regards, Arnold



Thanks! But... I'm just copying stuff I've seen, and guessing the rest. 
I might need to open the holes up more, I won't really know until I've made a jet holder and tried them. I may end up scrapping these, who knows. ;D


----------



## vlmarshall (Jul 27, 2009)

Instead of working on anything yesterday, I spent the morning goofing off *testing* both Crackers by running them on a hand-held torch. The second Cracker hasn't been run with the new piston and cylinder, until now.

Ok, really, I just wanted a cool "Cracker Moves" video like everyone else. ;D

I had to edit together several runs, because Cracker #1 insisted on stopping, usually at the far side of the track, whenever I pointed a camera at it. Stubborn thing.

[ame]http://www.youtube.com/watch?v=Ycz8F3p2fiM[/ame]


----------



## bearcar1 (Jul 27, 2009)

Around and around, and around again, I think I'm getting dizzy and may............ :toilet: urrpppp! Oh, terribly sorry. I forgot to take my Dramamine this morning. ;D Way cool little runner. I have been mulling over yet another variation on a theme for this one in my head. This will be neat to see it running on that great looking burner you have started.

BC1
Jim


----------



## vlmarshall (Jul 27, 2009)

bearcar1  said:
			
		

> Around and around, and around again, I think I'm getting dizzy and may............ :toilet: urrpppp! Oh, terribly sorry. I forgot to take my Dramamine this morning. ;D Way cool little runner.



Thanks... I think! ;D Somebody get a mop!




			
				bearcar1  said:
			
		

> I have been mulling over yet another variation on a theme for this one in my head.


Haha, do it! I've considered variations too. These Crackers have gotten me hooked, I'm going to be building more Locos after this, I'm sure.
 I've already printed plans for three more; D.Newman's "Simple Steam Loco", Watkin's deWinton "Idris", and Erik-Jan Stroetinga's "Dacre"...and then there's Keith Bucklitch's Brazil-class, J.P Duval's loco, etc. Today, a guy at work walked up and told me I should build a coal-burner! 

 The Cracker is the VW Bug of live steam locomotives. :bow:


----------



## putputman (Jul 27, 2009)

Vernon, I can only imagine how thrilled you were to see those little buggers running around the track. I will bet the only one that will be more thrilled than you is your dad when you present him with his engine. 

Will follow this build until the end.


----------



## vlmarshall (Jul 27, 2009)

putputman  said:
			
		

> I will bet the only one that will be more thrilled than you is your dad when you present him with his engine.



No doubt! He knows I'm building one for him, so it won't be a surprise, but it's something I HAD to do. ;D He started my interest in all things mechanical, some of the first books I remember reading were his set of Popular Mechanics Do-It-Yourself encyclopedias, a book called "The How and Why of Mechanical Movements", and assorted service manuals.

It wasn't until a month ago, that I found out/realized that the big ol' model train layout he built in the basement when I was 5 years old, he made 3 feet off the ground so I could see and use it. I never thought about HOW I was able to see it. ;D


----------



## BMyers (Jul 27, 2009)

Way Cool


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## shred (Jul 27, 2009)

Vernon  said:
			
		

> Thanks... I think! ;D Somebody get a mop!
> 
> Haha, do it! I've considered variations too. These Crackers have gotten me hooked, I'm going to be building more Locos after this, I'm sure.
> I've already printed plans for three more; D.Newman's "Simple Steam Loco", Watkin's deWinton "Idris", and Erik-Jan Stroetinga's "Dacre"...and then there's Keith Bucklitch's Brazil-class, J.P Duval's loco, etc. Today, a guy at work walked up and told me I should build a coal-burner!
> ...


Yeah, these things are silly fun to watch run around in circles. ;D ;D

Sometimes I'd only stop when I ran out of butane or distilled water, and work definately slowed down on the project.

If you're getting a lap plus with no burner, you're doing well. "Another one" is on my short list as well.


----------



## rake60 (Jul 28, 2009)

Looking *GREAT* Vernon! 

Rick


----------



## vlmarshall (Jul 28, 2009)

Thank you, everyone, for the comments. ;D You guys make this even more fun, especially on those days that I don't see any progress.


I may change burner designs before I finish the current experiment, and try this: http://www.southernsteamtrains.com/notes/radiantpokerburners.htm


----------



## shred (Jul 29, 2009)

Vernon  said:
			
		

> Thank you, everyone, for the comments. ;D You guys make this even more fun, especially on those days that I don't see any progress.
> 
> 
> I may change burner designs before I finish the current experiment, and try this: http://www.southernsteamtrains.com/notes/radiantpokerburners.htm


I considered that for a while, but in the end didn't end up needing it (or really having room for it-- IIRC your flue is a little larger). I also thought about stuffing a coil of nichrome wire in the end of the flue to capture some of the escaping heat and redirect it into the boiler, but didn't like the idea of a really hot bit of nichrome not far from the butane tank when refilling.


----------



## vlmarshall (Aug 3, 2009)

shred  said:
			
		

> ...but didn't like the idea of a really hot bit of nichrome not far from the butane tank when refilling.


Yeah, sounds like a glowplug to me. ;D

Speaking of safety, I got a new pressure gauge, and re-tested my boilers. Well, ONE of them, at the moment... I'm waiting for the pump to leak down.

After hearing more about how hard silver-soldering is, I'm sure I must have done something wrong with mine. I didn't NEED to build a firebox of bricks, was the solder melting point too low, with just a dull red glow to the copper to melt it?

Anyway, with a gauge that reads higher than 60PSI, and with Goodall valve in place, I just pressurized one of the boilers again. No leaks, no pop.






No wonder I sprung my first gauge, that pump puts out a LOT more pressure than I thought.... but I had no way of measuring it, before now.
That Goodall valve holds a LOT more pressure than I expected, too. I expected to get squirted. 

Edit: Yes, the Harbor Freight gauge says " 125 PSI 'MIX' " on it. : Nifty.


----------



## zeeprogrammer (Aug 3, 2009)

Vernon! Great progress.
For me, this would be a most dangerous point in the project. Once I see something work or run (i.e. know I can do it)...I quit and go on to the next one. Your advantage is building one for your Dad.


----------



## BMyers (Aug 3, 2009)

zeeprogrammer  said:
			
		

> Once I see something work or run (i.e. know I can do it)...I quit and go on to the next one.



I have the same problem. Most my engines only ever run once, then I start in the next.
I restored a Model T, once it was done, it sits. Anyone need an antique car ?


----------



## vlmarshall (Aug 3, 2009)

zeeprogrammer  said:
			
		

> Vernon! Great progress.
> For me, this would be a most dangerous point in the project. Once I see something work or run (i.e. know I can do it)...I quit and go on to the next one. Your advantage is building one for your Dad.



Zeep! Welcome back, and thanks! No worries here, I've never done the brasswork I'm about to do for the cabs, coal bunkers, and water tanks...and besides I want finish them and see how theyperform!
Yes, building one for my dad helps a lot, though. 




			
				BMyers  said:
			
		

> I have the same problem. Most my engines only ever run once, then I start in the next.
> I restored a Model T, once it was done, it sits. Anyone need an antique car ?


BMyers, the Model T sounds great! But, I've got my '62 bug I need to go through again. ;D I miss driving it.

As far as model engines, mine get lots of running time, look at that scruffy old Stirling I posted.


----------



## shred (Aug 4, 2009)

Vernon  said:
			
		

> Yeah, sounds like a glowplug to me. ;D
> 
> Speaking of safety, I got a new pressure gauge, and re-tested my boilers. Well, ONE of them, at the moment... I'm waiting for the pump to leak down.
> 
> After hearing more about how hard silver-soldering is, I'm sure I must have done something wrong with mine. I didn't NEED to build a firebox of bricks, was the solder melting point too low, with just a dull red glow to the copper to melt it?


If you used cadmium-bearing silver solder, that sounds about right. It was the Cd-free stuff I had to get orange-hot.



> Anyway, with a gauge that reads higher than 60PSI, and with Goodall valve in place, I just pressurized one of the boilers again. No leaks, no pop.
> 
> No wonder I sprung my first gauge, that pump puts out a LOT more pressure than I thought.... but I had no way of measuring it, before now.
> That Goodall valve holds a LOT more pressure than I expected, too. I expected to get squirted.


I would have thought the rubber would give way before that... it's really eye-opening the first time you hydro test something with a little pump how much pressure it can exert.


----------



## vlmarshall (Aug 4, 2009)

shred  said:
			
		

> If you used cadmium-bearing silver solder, that sounds about right. It was the Cd-free stuff I had to get orange-hot.
> I would have thought the rubber would give way before that... it's really eye-opening the first time you hydro test something with a little pump how much pressure it can exert.



As long as this stuff has been around at work, I'm sure it's Cd-bearing.
My Goodall valves are using silicone fuel tubing. ;D
I'm not using a homebuilt hand pump, I cheated, dug through my junk, and found a 12v diaphragm pump from a sprayer. ;D It works, and quickly, although it'll leak that 140PSI down to 50 or 60 in about 45 minutes.


----------



## vlmarshall (Aug 4, 2009)

No real progress today. "Fixed" the Goodall valve that i accidentally drilled through, by tapping the end for a 2-56 Torx-head screw I happened to have.





Also, I turned the step-coupler into a woodburner-style "spark arrestor" stack for my dad's Cracker.
I should have turned the top ring out of a seperate piece, and made it brass. Oh well. Maybe I'll change it later.





Last of all, I blackened my third set of wheels, the extras... and lost one, dropping it off my bench at work to roll who-knows-where. That was going to go on a railcar...guess I'll make more.


----------



## BMyers (Aug 4, 2009)

Lookin' good Vernon, I am eager to get back on mine.


----------



## Deanofid (Aug 4, 2009)

This is such a good project, an you're doing a great job, Vernon. I've been reading along since I joined the group, and am enjoying your adventure. I don't have any rail road stuff, but seeing these little guys run gets me thinking... 

Keep it up, and well done!

Dean


----------



## vlmarshall (Aug 4, 2009)

BMyers  said:
			
		

> Lookin' good Vernon, I am eager to get back on mine.


Thanks! Yeah, I'm eager to see more of yours, too... especialy on days when I don't get anything done on my own. One of this pair of Crackers: http://www.16mm.org.uk/mom2008-10.htm uses a burner right off of the Harbor Freight pencil torch. I would have tried it if either of mine worked for any length of time.




			
				Deanofid  said:
			
		

> I don't have any rail road stuff, but seeing these little guys run gets me thinking...


Thank you, Dean!
Do it! Build one of these, I bet you'll get as big of a kick out of seeing it MOVE for the first time, as I did!
I'm hooked, I'll be building more locomotives after these two. ;D


----------



## vlmarshall (Aug 11, 2009)

A while ago I posted this in BMyers' Cracker thread, about finishing my Cracker frames in a black color:



			
				Vernon  said:
			
		

> I'm either going to,
> (a) Set up another anodizing tank and do it myself. Surprisingly easy.
> (b) Wait for a batch of stuff going to be anodized at work, and include my parts. Could be a while.
> (c) Send my parts to the local plater and PAY for anodizing. Not likely.
> ...



Today, I'm doing A and B. Work needs some parts anodized, the local platers went out of business/stopped anodizing, and they know I can do it.
So, I've got homework today, and a project tomorrow. ;D
Actually several, I've got a bunch of aluminum parts waiting, including the table on my mill.


----------



## zeeprogrammer (Aug 11, 2009)

Tell us all about 'A'. Well...tell me anyway. 'They' may know, but I don't.


----------



## vlmarshall (Aug 11, 2009)

Hot and sweaty. Hot rubbery apron, hot elbow-length gloves, acid fumes, and mosquitoes trying to carry me off by my exposed elbows.

And now I hear a thunderstorm warning. :-\

I'll post some pictures and a description when I'm done with the test pieces... which they gave me to try... they THINK they're 6061 alumiunum... I hope so, or it won't come out right, I didn't do the lye bath.



Edit: Darn. It was 7075 aluminum. Ugly now.


----------



## vlmarshall (Aug 14, 2009)

So, I tried again, with a different alloy.
This time, I roughed out a pair of heatsinks, for the battery charger I'm using to anodize, and dyed them black, instead of the apparently more-difficult red I tried on the first piece.
This way I could verify my acid mix was correct, and get an idea of the amperage and 'cook' time I'd need.
These parts were abrasive-blasted before anodizing, so they have no shine.






Using less amperage this time, I let the parts run for 3 hours (!) before pulling them out. The finish was nice, so they went into the dye bath (black RIT clothing dye mixed at 4x strength), and then were boiled to seal them.
I should have used a larger container and suspened the parts from wire hooks, because one of the parts was scratched up by the other before sealing. oh well.






Now I'm running another part, 6061 aluminum, fully machined finish, to re-try the red dye. 
Cracker parts after that, if the rain stays away.


----------



## zeeprogrammer (Aug 14, 2009)

How did you know it was 7075?
And how do you know how to anodize? Got some references you're following?

Thanks.


----------



## vlmarshall (Aug 14, 2009)

zeeprogrammer  said:
			
		

> And how do you know how to anodize? Got some references you're following?



Anodizing seems to be one of those things that's easy to do _fairly_ well, and difficult to do expertly. I first read about it online around '95... there are a million pages out there about it! ;D It's not something I'd do anywhere other than outside, as acid fumes are no fun, and safety gear is a must. 

I suspected my first test piece was 7075, and the oddly-pitting surface... makes me suspect it even more strongly. ;D Although, the acid bath temperature DID get too high, which will also pit a part quickly, and seal the surface before you get a chance to dye it. Still, I should have dunked the part in a lye bath first, it'd have come out better.


----------



## vlmarshall (Aug 15, 2009)

Ok, back to Crackers. The footboard pilot, or "cowcatcher" for Loco #1 is mostly finished.

It's just a piece of aluminum angle, sawn out and drilled- all rough handwork, no machining on this one.





Brass tubing, .050" and .062" diameter, runs through the holes. Failed red part in the background.





Just a quick idea of what it'll look like:


----------



## zeeprogrammer (Aug 15, 2009)

Good stuff!
How did you mount the part for drilling?
How are the tubes held?

And where's Chip?


----------



## vlmarshall (Aug 15, 2009)

zeeprogrammer  said:
			
		

> Good stuff!
> How did you mount the part for drilling?
> How are the tubes held?
> 
> And where's Chip?



Mount it? That thing's all hand work. Part in one hand, cordless drill in the other.
Ok, I centerpunched the two rows of holes first, drilled them perpendicular to the plate at .040", went back and drilled them again swinging the drill toward it's opposite hole to cut the angle. Then opened them up to .050", and .062" for the center post. The brass tubes are bit of a press fit, with some superglue to convince them to stay put.

Chip isn't to scale for Loco #1... my dad doesn't like the look of the tall skinny cab on #2.
So, I'll cheat the scale a little, and scale the cab for a slightly shorter human:


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## zeeprogrammer (Aug 15, 2009)

??? Are you saying that's 'dad' ???
Good looking fellow. Do you take after him?


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## vlmarshall (Aug 15, 2009)

Cracker Loco #2 is in the acid.

Here's a "Cracker Racker" shot taken beforehand. I'm not carrying my camera outside, anywhere near acid fumes.







...and, Zeep, I ain't answering that. ;D


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## vlmarshall (Aug 15, 2009)

Crap. :-\

I knew I shouldn't have tried to do that many parts at once.

Maybe I had the amperage too high.

Maybe the acid bath was a bit TOO warm.

I've just added a bunch of parts to my wall of shame _accidental hard-coat anodizing._

Ah well, at least it was on MY Cracker... I wanted a more industrial-looking loco than my dad's. :big:

I might leave it this way... but the frame stretchers (the end pieces) NEED to be stripped and re-done.






Oh well. :-\


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## zeeprogrammer (Aug 15, 2009)

Sorry to hear that.

I know very little about anodizing and I can't tell from the pic...
What exactly is wrong?
You can strip anodized material? How?


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## bearcar1 (Aug 16, 2009)

Say Vern', if I recall correctly the acid bath should be held at a relatively constant temperature range of 70-75*F, as the temperature increases the coating becomes more porous. 14-18 V and a current density of 10-25A/ sqft. This is based upon a 15% acid solution at 12floz/gal. 15-30 minute bath exposure time. What are you using for a Cathode? (as far as surface area?) I'm pretty certain these figures are correct albeit it has been several years since I had an opportunity to do this type of work. Good luck and your engines are way cool, the 'cowcatcher' is a novel idea as is the faux spark arrester. 

BC1
Jim


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## vlmarshall (Aug 16, 2009)

bearcar1  said:
			
		

> Say Vern', if I recall correctly the acid bath should be held at a relatively constant temperature range of 70-75*F, as the temperature increases the coating becomes more porous. 14-18 V and a current density of 10-25A/ sqft. This is based upon a 15% acid solution at 12floz/gal. 15-30 minute bath exposure time. What are you using for a Cathode? (as far as surface area?) I'm pretty certain these figures are correct albeit it has been several years since I had an opportunity to do this type of work. Good luck and your engines are way cool, the 'cowcatcher' is a novel idea as is the faux spark arrester.
> 
> BC1
> Jim


Thanks for the info! Right now I'm running 30% acid , what should be a 14v battery charger, but drops under load to around 10v, acid temperature is only somewhat controlled, with a surrounding water bath and added ice. Right now the acid is climbing to 80 degrees, but I'm about to pull out my parts after a 45min run-time. I only have two charger settings, 2A or 10A, so I try to match the area to 14A/ft2 by adding more parts.
Last night's run was 30 minutes at 10amps, the cowcatcher was in the bath for 45 mins with an 8in2 part, at 2 amps, with great results.
Eventually I'll add air agitation and a better current controller and power supply.
Thanks again for the help... my results are still all over the place, because I've got too many variables. Don't say it, Zeep!


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## bearcar1 (Aug 16, 2009)

One can *never* have too many variables. It would make life very dull. :big: It sounds like you have a decent handle on your situation Vern', at least you understand the principles involved. Of course the usage of distilled water is a must as well. As you say, too many variables and not enough control. Have fun and be careful, I know you'll "git 'er done' ;D

BC1
Jim


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## BMyers (Aug 16, 2009)

Vern,
start watching ebay for a constant current power supply


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## vlmarshall (Aug 16, 2009)

Yes, distilled water everywhere, except for the cooling bath.

BMyers, yes, I will... either buy or build one.
Well, I've just taken (taked? what kind of typo was THAT?) this batch out of the dye, and they look great. The footplate is for Loco #1, and the end pieces are Loco #2's, from the last batch.
I filed off the anodizing on the faces that show, expecting only those to clean up, but re-anodizing the part made ALL of the faces look great. I thought I'd have to strip the anodizing off chemically.






These parts actually look a lot worse on camera. ;D


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## arnoldb (Aug 16, 2009)

Looking good Vernon 



> These parts actually look a lot worse on camera.


So you've got one of those "defective" cameras as well ? :big:
Regards, Arnold


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## vlmarshall (Aug 16, 2009)

arnoldb  said:
			
		

> So you've got one of those "defective" cameras as well ?



 ;D Yeah, the lens must be scratched! They show up on all my parts! 

Loco #1 is reassembled, except for the rear frame stretcher, which had a spot i didn't like.
The footplate for Loco #2, that came out ugly yesterday, has been re-anodized and looks good. 

Edit: Cowcatcher's mounted. Work progresses slowly. I'm not adding a new post just to say that. ;D

Here's a different photo.
I guess I'll either add a pair of buffers, or change these bolt heads for something different, eventually.


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## vlmarshall (Sep 5, 2009)

Not much progress lately, but, to keep Zeep happy, I'll post an update. I remade the crank disks because the crankpin kept coming loose from the bigger of these two engines.
Maybe the added mass will also add more flywheel effect.







Yes, that's a tiny chuck, not a 3-foot set of parallels. ;D


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## zeeprogrammer (Sep 6, 2009)

Vernon  said:
			
		

> but, to keep Zeep happy



Well...if you want to make Zeep happy...I'd have some suggestions... :big:
We can start with the beer... :big: My memory may be crap...but not when it comes to things important. At least...as far as I can remember.

Good! Everyone wants to see those Crackers running.


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## cobra428 (Sep 9, 2009)

Vernon,
Are you going to put couplers front and rear so you can run the two in a consist?
Tony


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## vlmarshall (Sep 9, 2009)

cobra428  said:
			
		

> Vernon,
> Are you going to put couplers front and rear so you can run the two in a consist?
> Tony


No, the one with the "cowcatcher" is going to my dad, where it'll see only occasional use as anything other than a display. It's being built to more of a "toy-scale" than the other loco, which I'm keeping with the intent of running until it's worn out many many replacement parts. Mine will have couplers front-and-rear, and the first time I repower it, it'll have a reverser valve and perform shunting tasks.

That doesn't mean the two won't get together from time to time for a doubleheader, I'll just make his the pilot engine. ;D


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## Krown Kustoms (Sep 9, 2009)

It looks great so far, I kind of showed up in the middle of this build.

Your anodize process sounds good, I use 1:1 battery acid solution from the batteries pluss store to distilled water.
I have a 2,5,10.40,100,200 amp snap on battery charger and it seems like I either have too much or not enough amperage every time I set up something so I have to find more things to anodize.

My dad is a big kid with railroad, from n to g scale, I have been wanting to build him a g scale steamer.
seeing your build gives me motivation and ideas thanks
-B-


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## vlmarshall (Sep 13, 2009)

Krown Kustoms  said:
			
		

> It looks great so far, I kind of showed up in the middle of this build.
> 
> Your anodize process sounds good, I use 1:1 battery acid solution from the batteries pluss store to distilled water.
> I have a 2,5,10.40,100,200 amp snap on battery charger and it seems like I either have too much or not enough amperage every time I set up something so I have to find more things to anodize.
> ...



Thanks! Your battery charger sounds like the one I used to own, back when I first tried anodizing.

The nice thing about these Crackers is that they're an easy introduction to 16mm scale, running on O-gauge track representing 2-foot, narrow-gauge railways. Build one! 

Today I spent a lot of time making a door for Loco #1's smokebox. Zeep calls it "cheating" because I'm using CNC. No matter, I'm already "cheating", doing my lathe work at work!

 It could have gone better, twice I knocked the thing loose from it's superglue mounting. It seems that Tap Magic might dissolve cyanoacrylate. :-\ Also, I adjusted my mill's backlash before running the job, and forgot to change the settings on the controller, effectively dialing in some "unbacklash". Oops.

At any rate, here's a few pictures of the nearly finished door. I still need to deburr the thing, clean up the ugly spots, drill the center hole for a locking handle, and finish the hinge. Maybe tomorrow, or later today, or whatever. I need sleep.


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## zeeprogrammer (Sep 13, 2009)

Nice work Vernon. Are you making another like it for the other loco or a different design? How was it milling copper?

Cheating? Did I say it was cheating? I don't want anyone to get the wrong idea about me. We should understand the context. The context included you. That should be sufficient understanding.  On the other hand...the context included me. Ah...we'll stop there.

I bought both the lathe and mill with the idea of converting them to CNC someday.

Great progress. Keep going. A lot of people are interested.


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## itowbig (Sep 13, 2009)

wow this is great. got me inspired to hunt all the parts down to make me one. great build thank u for the detailed posts. this is great. im following along.


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## vlmarshall (Sep 13, 2009)

zeeprogrammer  said:
			
		

> Nice work Vernon. Are you making another like it for the other loco or a different design? How was it milling copper?
> Cheating? Did I say it was cheating? I don't want anyone to get the wrong idea about me. We should understand the context. The context included you. That should be sufficient understanding.  On the other hand...the context included me. Ah...we'll stop there.
> I bought both the lathe and mill with the idea of converting them to CNC someday.
> Great progress. Keep going. A lot of people are interested.


Thanks Zeep! The other loco will get another door design, one that more completely covers the front of the smokebox. The idea was to use a smaller door on Loco#1, to make the whole thing look bigger in comparison. I hope it works.

Edit: Oh yeah, milling copper... the stuff is gummy. Two-flute endmills are a must.

Cheating, wellll.... I did say at the beginning of this thread that I was "cheating" in using CNC. There are people on here that can do more with a hacksaw and a hammer than I can with a machine shop. 
Yes, convert to CNC. Starting with manual is the only way to go, in my opinion. People that have never turned a crank have no idea what they're asking a machine to accomplish, and usually end up blaming the mill, the cutter, the vise, the computer, the stepper motors, the influence from a sleeping undersea elder being from beyond the stars... 





			
				itowbig  said:
			
		

> wow this is great. got me inspired to hunt all the parts down to make me one. great build thank u for the detailed posts. this is great. im following along.


Awesome. Shred started it, but I'm glad to spread Cracker-itis to more people. I really enjoy seeing all of the variations on these things. Post lots of pictures. ;D Thanks for the kind words!


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## Krown Kustoms (Sep 13, 2009)

Vernon
I definately am looking into a loco build, I was brought up around railroading.
My dad is a big fan of on30, a little smaller than the cracker, but he has G scale also, I think that size is more suitable for a first loco build. (for me)
thanks for the motivation and the detail I see that can be achieved.
-B-

p.s. I too "cheat" with CNC, I catch myself trying not to use it on simple things, I guess so I dont feel like Im cheating 
(not sure what im trying to say here)


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## vlmarshall (Sep 14, 2009)

Knocked out another part last night, the front of the smokebox for Loco #1. This part will probably get some detail work on the outside, and it still needs the hinge block added to the small hole.

[ame]http://www.youtube.com/watch?v=dWD3zk6zf58[/ame]


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## zeeprogrammer (Sep 14, 2009)

Nice Vernon.
Nice video too...I liked the changeover to slides.
How did you finish the door? It looks real smooth.


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## 4156df (Sep 15, 2009)

Vernon,

Really liking this thread. Keep the photos and videos coming.

Dennis


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## Deanofid (Sep 15, 2009)

Looks really nice, Vernon. What did you use to hold it to the fixture plate? Super glue?

Dean


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## vlmarshall (Sep 15, 2009)

Thanks! I'm enjoying building these. Zeep motivated me into making these two parts this weekend. 
Oh yeah, that part was lightly scrubbed with a 3M or 'scotchbrite' pad.




			
				Deanofid  said:
			
		

> What did you use to hold it to the fixture plate? Super glue?


Yes, these two parts are the only time I've ever used superglue to hold a part. Usually it's doublesided tape, clamps, or softjaws, if I can't just drop them into a vise... while glue is more expensive than tape, it seems to work well.


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## jthulin (Sep 15, 2009)

Brilliant, Vernon. What a great thread :bow:


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## RobWilson (Sep 17, 2009)

Out standing Vernon, very interesting post, i see your doing a great job of putting your own stamp on the build :bow: :bow: :bow:

Regards Rob


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## Deanofid (Sep 17, 2009)

Vernon  said:
			
		

> Yes, these two parts are the only time I've ever used superglue to hold a part. Usually it's doublesided tape, clamps, or softjaws, if I can't just drop them into a vise... while glue is more expensive than tape, it seems to work well.



It's great stuff for thin parts. I use it all the time for holding thin gear blanks to a face plate when turning them to size. 

Dean


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## vlmarshall (Sep 17, 2009)

Thanks, everyone! You guys make this even more fun. ;D




			
				Deanofid  said:
			
		

> It's great stuff for thin parts. I use it all the time for holding thin gear blanks to a face plate when turning them to size.


Yeah, I'm going to be using it a LOT more often, both at home and work.


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## vlmarshall (Sep 21, 2009)

Ok, I finished the hinge, and now I only need to make the latch and handles. While Zeep was pushing me to make parts, I decided to cut out a mount for a miniature bell that I bought at a craft store. 

Who says you can't un-ring a bell? Since the bell is made of brass-plated steel, it looks better than it sounds. So, I made the mount all in once piece, with a dummy arm, and removed the clapper from the bell. The arm will be drilled for a miniature pull-cord, which will still fail to produce sound from this mute bell. ;D

I'll cut down the thread, or add a decorative nut, on the bolt holding the bell.






I also threw together another video, with some footage of both the hinge and bell bracket construction.
[ame]http://www.youtube.com/watch?v=BrxcutWAj2Q[/ame]


Also, this one's for Zeep and his "Failure Percentage" calculations; The first time I made the bell bracket, I was taking roughing cuts that were too much for the doublesided tape, and popped both parts off of the 'fixture', ruining them both. So, the bell bracket has a 66% failure rate. ;D


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## arnoldb (Sep 21, 2009)

Good going Vernon - looks a treat


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## bearcar1 (Sep 21, 2009)

Over the top coolness 8) Vernon. What a novel idea to make a bell bracket. Truly a "ringer" (yeah I know, *_groan_*) of a detail. :big:

BC1
Jim


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## zeeprogrammer (Sep 21, 2009)

Excellent vid Vernon...nice backdrop with the cowcatcher and the ending was genius with the locos in the background. Beautiful.

Oh! And nice parts too. :big:


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## Krown Kustoms (Sep 21, 2009)

Yes nice parts, they look great
-B-


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## vlmarshall (Sep 29, 2009)

bearcar1  said:
			
		

> Truly a "ringer" of a detail. :big:


Oh that was terrible. ;D


Well, I've started cutting brass. Not just any brass, but the .031" sheet brass I ordered for the bodywork. This has been fun so far, although I'm going cross-eyed from staring at drawings.
Possibly I've overdone it with the nails-as-rivetheads, but they'll be a lot more subdued when they're painted over.

Two sides and a small tank.





Bending the start of the steps.





A nailhead rivet.


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## vlmarshall (Oct 10, 2009)

Well, I've moved back to Loco #2, following Zeep's suggestion about the dreaded "Project Shift". If I finish the one for my dad first, I might get bored and not finish my own. So, I'll finish my own first. 

In my last post, I was showing off a few of the brass parts for the cab. I'm REALLY having fun making these, and it looks like I'll be working out all of the construction bugs on my own Cracker before moving to my dad's.

I still need to make the other sides of the water tanks, and the coal bunker/ fuel tank. This stuff is fun to work with.











[ame]http://www.youtube.com/watch?v=uaJKyTJZp7c[/ame]


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## zeeprogrammer (Oct 10, 2009)

Very nice Vernon.

And thanks. I'm glad to know I contributed to changing someone's direction. :big:

Nice video too. When I see all the holes being made...CNC looks enticing.

Looking forward to seeing more on the sheetmetal work. I know that's in my future and I have a lot of learning to do.

It's odd to me seeing those windows 'floating'. Double stick tape eh?

Was the metal already 'brushed'? What, if any, prep work did you have to do before milling?


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## vlmarshall (Oct 10, 2009)

zeeprogrammer  said:
			
		

> Very nice Vernon.
> And thanks. I'm glad to know I contributed to changing someone's direction. :big:
> Nice video too. When I see all the holes being made...CNC looks enticing.
> Looking forward to seeing more on the sheetmetal work. I know that's in my future and I have a lot of learning to do.
> ...



Thanks! Yeah, you had a good idea with that.
CNC hole-drilling, it almost seems like cheating. Almost.
You'll see more sheetmetal work, I need to finish the water tanks soon.
This sheet metal is a lot of fun, after hours of drawing, tape it down and go.

I've got the basic cab parts soldered together, it's quite solid.


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## arnoldb (Oct 11, 2009)

Good going Vernon; - Now get it done; I need tips! :big:


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## bearcar1 (Oct 11, 2009)

Those pics almost makes me want to pull on my coveralls and gloves and step into the cab for a short steam around the loop. Those are going to be a set of fine looking locos when you are finished, and I am certain that your Dad is going to be thrilled beyond words. 

BC1
Jim


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## 4156df (Oct 11, 2009)

Vernon,
This is really looking good. Keep the pictures coming please.
Dennis


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## ChooChooMike (Oct 11, 2009)

Great stuff Vernon !! Thm:

How about some pictures of your CNC rig ? Looks like a Sherline mill ? What software are you running, Mach3 ?

Thanks!
Mike


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## zeeprogrammer (Nov 8, 2009)

stickpoke stickpoke stickpoke


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## zeeprogrammer (Jan 9, 2010)

What's it going to be Vernon?

"Move along folks."
"Nothing to see here."
"Go about your business."

or....

"WATCH THIS SPACE!"
"COMING ATTRACTIONS!"

 stickpoke


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## ariz (Jan 9, 2010)

what a great work you're doing here Vernon :bow:

astonishing


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## 1hand (Jan 9, 2010)

Looking great Vernon! Pretty soon your locos will be going round and round..............


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## vlmarshall (Feb 17, 2010)

Thank you all for those kind words. 

 Several months ago, my workplace shut down the second-shift, cutting off the majority of my play-time and halting my progress on the locomotives, for want of a lathe.

Until now.


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## BigBore (Feb 17, 2010)

"In our last episode, we joined Vern just as a mysterious cardboard crate had followed him home. 

The tension mounts as we wonder, "Will he open it? Will it open itself? <gasp>" In today's thrilling episode.........
 th_confused0052



.


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## zeeprogrammer (Feb 17, 2010)

A box. It's a box. Wow. A box.

I must repeat my previous post...



			
				zeeprogrammer  said:
			
		

> What's it going to be Vernon?
> 
> "Move along folks."
> "Nothing to see here."
> ...



Or are you going to tell me that that's *A* 'Coming Attraction'?

C'mon...open the box...........let us see.


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## vlmarshall (Feb 17, 2010)

Yeah yeah, it's got it's own thread!
This space reserved for Locomotives.


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## Deanofid (Feb 17, 2010)

I love that box. If it helps Crackers, it's cool.

Dean


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## zeeprogrammer (Mar 21, 2010)

Feb 17 was the last post.
Today is Mar 21.
You recently got a lathe.
C'mon guy...show us something. stickpoke stickpoke stickpoke
That...or pay the beer you owe...then I'll leave you alone.


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