Fairbanks 80HP 3 Cylinder Model

[Brian Rupnow]

Chuck--Learning when to leave "good enough" alone is one of the major milestones of model machining!!! Love your work.---Brian

 

[Philjoe5]

Great work Chuck and your documentation is appreciated.Thm:

Cheers,
Phil

 

[metalmad]

Thats going to be a classic Chuck!
Pete

 

[Generatorgus]

Chuck, Ya got to love that Loctite, but pinning the shaft was what I think a very important back up.
Just recently, when I removed the connecting rod from my Wyvern, I found a disturbing thing.
A failed Loctite connection.



I Loctited the big end bearing as well as the big end SS piece to the connecting rod ( the end of the conn rod is reduced in dia. and runs thru both pieces almaust to the crank pin. Because the connection looked a bit scary just Loctited I pinned the SS piece only, thinking that if that joint failed it would be a backup. I had/ have less than 10 inutes run time on the engine. On disassembly the bearing was no longer glued, thankfully the bolts held it together. THe SS part was stiil nice and tight.
As part of my do-overs I'll reglue it and pin the bearing also.
Oh Yeah, I glued and pinned the crankshaft, also, it's still nice and tight.


About cleaning the crankshaft up, what Brian said.
Looks good in the picture.

GUS

 

[cfellows]

Thanks all for the words of encouragement.

Started working on the intake manifold today. It will be built up of some turned parts, model plumbing fittings, and brass tubing. Fiddly bits that I'm not fond of, but they are a challenge and they need to be done.
To make the parts that attach to the heads, I started with 1/2" x 1/4" brass bar chucked in the lathe. and turned down a 3/16" nipple with a flange.

Here are the 3 parts with the lathe work finished. Also shown is the plumbing parts tree that will contribute the elbows & tees...

In this photo I'm drilling the mounting holes in the flanges. I'm using my small rotary table clamped in my milling vise. This gives me better control on the hole location and ensures that all three pieces will be drilled the same.

I needed to radius the ends of the flanges and a) I don't have a filing rest, a problem I need to resolve some day, and b) the drilled holes in the flanges are not at the center of the radius. So, I had improvise a filing guide for this occasion. I guess the picture says it all.

Here I have one of the plumbing tee's mounted in my toolmaker's vise ready to drill the openings. Both holes are drilled without removing the tee, but rather, just flipping the vise over on its side for the second hole. Using the vise in this manner ensures that the drilled holes will be square to each other.

And, here's a preview of what the finished manifold will look like. The pieces will all be soldered together in place on the assembled engine so they will be properly spaced and aligned.

Next, I'll cut the flats and drill the holes in the heads for intake manifold.

Chuck

 

[cfellows]

Got some more work done on the heads. In the first photo I'm Milling the pocket for the intake manifold piece.

After I milled the pockets, I drilled the intake hole in the middle of the pocket, then I loctited the brass pieces in the pockets to hold them while I drilled the pilot holes for the mounting screws.

After a bunch more milling, drilling, and threading, here's the progress for today.

Chuck

 

[cfellows]

Ugh... Tapping! This has to be one of my least favorite activities. Today I made a drilling jig to accurately position the mounting holes in the cylinders and crankcase. One end is shouldered down to fit snugly in the crankcase top.

And the opposite side has a recess that the bottom of the cylinder fits into.

I used this to drill the 18 cylinder mounting holes in the crankcase.

These are 2-56 screws. I plan to cut the heads off to form studs and the cylinders will be attached with 2-56 model hex nuts. Today I ordered 50 of the nuts and a bunch of 12L14 hex rod from American Model Engineering supply. I had to order them by snail mail and I'm hoping they don't take too long to get here.

Chuck

 

[hitnmiss49]

Chuck,

It is really looking good. Hope we will see a video very soon. Here is a link where I purchase model size nuts and bolts. I have always received my orders very quickly from them. Their prices are quite reasonable.
http://www.fastener-express.com/hex-nuts-stainless.aspx

Lonnie

 

[cfellows]

Chuck,

It is really looking good. Hope we will see a video very soon. Here is a link where I purchase model size nuts and bolts. I have always received my orders very quickly from them. Their prices are quite reasonable.
http://www.fastener-express.com/hex-nuts-stainless.aspx

Lonnie

Thanks Lonnie. I looked at the website you listed. Unfortunately, the nuts are not to scale. For example, their 2-56 nuts are 3/16" across the flats. The scale model nuts are only 1/8" across the flats. Also, unfortunately, the scale model are also a lot more expensive!

Chuck

 

[slaurenson]

Hi Chuck.

Have to say I am loving this build and your updates, the photo's are magic.. given that I am building my first ever double acting vertical steam engine at the moment, I am still surprised at my self when something turns out nice (how it should be according to the plans) and people say to me "Oh did YOU make that?" I can't imagine the feeling you get from producing something so beautiful.

 

[cfellows]

Hi Chuck.

Have to say I am loving this build and your updates, the photo's are magic.. given that I am building my first ever double acting vertical steam engine at the moment, I am still surprised at my self when something turns out nice (how it should be according to the plans) and people say to me "Oh did YOU make that?" I can't imagine the feeling you get from producing something so beautiful.

Thanks.

Finished drilling the mounting holes in the cylinder base today. I used a bolt through the cylinder and the drilling guide fixture to hold the two together. Then mounted the assembly in my toolmaker's vise to drill the holes.

I also drilled and tapped the cylinder head mounting holes in the cylinder. Then I started making it purty. I finished the shaping and contouring of the head and cylinder. Heres another assembled picture.

Chuck

 

[cfellows]

Nothing very exciting today. I made the valves out 1/4" drill rod and cut the grooves for the e-clips with a dremel cutoff blade. I also cut the o-ring grooves in the valve cages.

Now I am pondering whether to make a cam from solid or make a built up cam.

If I make it from solid, I'll have to start with 3/8" rod and I'll have to devise some kind of cam grinder. Also, I'll have to enlarge the bore in the crankcase to 3/8", a task I'm not real comfortable with.

If I make it from components, I can use 1/4" drill rod and the finished holes with no further modifications to the crankcase. I can make 3 separate cam lobes and attach them with set screws, but they will be a somewhat larger than scale and because of the extra attachment lobe, it won't look as authentic.

Decisions, decisions...

Chuck

 

[kilocharlie]

Chuck,
Your first photo on post #54, when you cut the gears - you mentioned the Arduino stepper motor setup that greatly reduced the chance of error in gear cutting. Could you post a photo of the setup, or perhaps photos of the machining sequence? Sounds like possibly an improvement over a dividing head and compound indexing. I'd love to hear more details and opinions from you.
Thanks, - Casey.

 

[cfellows]

Chuck,
Your first photo on post #54, when you cut the gears - you mentioned the Arduino stepper motor setup that greatly reduced the chance of error in gear cutting. Could you post a photo of the setup, or perhaps photos of the machining sequence? Sounds like possibly an improvement over a dividing head and compound indexing. I'd love to hear more details and opinions from you.
Thanks, - Casey.

Here's a link to the build thread I posted on this forum when I was making the dividing head.

http://www.homemodelenginemachinist.com/f39/electronic-dividing-head-using-arduino-17896/

Here's a link to a couple of videos I made using the electronic dividing head.

https://www.youtube.com/watch?v=R1Nk4_cjvbw

https://www.youtube.com/watch?v=A6CrFMwxbxQ

Chuck

 

[cfellows]

A little bit more done on Saturday. I finished up the pistons.

Time to start on the connecting rods. Here's some 2.75" x .625 x 1/4 pieces that will be made into the rods.

Chuck

 

[Lawijt]

Hi Chuck,

If you build the connecting rods , can you show us how you do it step by step please. It will be very helpfull.
Thanks.

Barry

 

[kilocharlie]

HUGE THANK YOU, Chuck! I will be reading over the thread about the dividing head. Looks awesome. Great idea!

 

[cfellows]

Hi Chuck,

If you build the connecting rods , can you show us how you do it step by step please. It will be very helpfull.
Thanks.

Barry

OK, Barry, ask and ye shall receive...

I took some detailed photos of my process for making connecting rods.

After cutting and squaring the blanks, I mark the center line and a crossing line where the rod cap will be separated from the rod.

Next, I drill the holes in the end for the screws that will secure the rod cap to the rod.

These holes are drilled with the pilot bit for the screw threads to be tapped later.

Next I cut the rod cap away from the rod body. This is done in my mill / drill with a circular cutoff blade.

The next step is to tap the holes for the rod cap screws in the rod body and enlarge the holes in the rod cap to the 2-56 screw size I'm using to secure the rod caps to the rod.

Then I screw everything together to see how it fits and, of course, to get another picture...

With the rod caps screws securely to the rods, I drill and ream the hole for the crankshaft end of the rod.

Then, I remove the rod caps, mark the location and drill the piston end of the rod.

Then it's time to contour the sides of the rod. Here is a picture of the special vise I made a number of years ago to secure things so they could be mounted in the milling vise and milled on the side.

And here's what it looks mounted in the milling vise. Unfortunately I forgot to take a picture during the process and had to back and take this picture after the rods were finished...

And here's the rods after I finished contouring the sides.

Next I need to work on the piston end. I used my bandsaw to cut of some of the extra material.

Then I mounted the rod on my rotary table to round the piston ends of the rods.

And here's what the finished rods look like...

Next I think it will be time to tackle the camshaft.

Chuck

 

[kilocharlie]

Is the side milling fixture a vise jaw with a clamp on top? I might have mounted the rods through the holes with tight-fitting bolts, but I love your solution.

 

[Lawijt]

Thanks for the explaining and the pictures Chuck. It looks great.
Now I understand how it works.

Barry