Building Kozo's New Shay locomotive

[crueby]

Lookin' good! Wheels do take a lot of time. Many operations to repeat.

Todd

fortunately only 8 wheels (am making a 9th as a spare - do trains have a trunk for the spare tire??)

THIS project was one with a ton of repeated parts - a 4' scratch-built 74-gun ship model I did a few years ago. 74 canon to turn, plus 148 carriage sides, plus 148 axels, plus 296 wheels.... That part got a little old eventually. Was worth it in the end to see the finished product though!

 

[SilverSanJuan]

WOW! That's an incredible model. I love wooden ship models. Great work!

 

[tms6401]

I love that sailing ship, but I agree that so many of the same pieces would get old very fast!

I see you are using a Sherline lathe and mill, and I have to ask ... how do you like using the smaller machines? Your results show they are certainly up to the task, but do you find them awkward at all? I only ask because I am thinking of selling my larger mill and lathe and converting to the Sherlines. (Downsizing due to health and age issues ... the big stuff is too heavy to move around anymore)

TMS

 

[Swifty]

Hi Bob, the loco is looking great, and that ship is amazing. I don't think that I would have the patience to do something like that.

TMS, sometimes I wish that I had a smaller lathe, when I'm turning parts down to 2mm dia on a large lathe I'm always thinking that I could do this better on a smaller machine.

Paul.

 

[crueby]

I love that sailing ship, but I agree that so many of the same pieces would get old very fast!

I see you are using a Sherline lathe and mill, and I have to ask ... how do you like using the smaller machines? Your results show they are certainly up to the task, but do you find them awkward at all? I only ask because I am thinking of selling my larger mill and lathe and converting to the Sherlines. (Downsizing due to health and age issues ... the big stuff is too heavy to move around anymore)

TMS

Sometimes the smaller machine can be limiting, cant do a big flywheel, and the power is not there to cut large stainless steel, etc, but overall I like them. Do have to get creative on how tomake certain things, like large dia. gears.... Sometimes it doesnt have the rigidity i would like, backlash tolerances are not as easy to maintaon than some. For my use, in a small shop, it is fine. It is perfect for small parts like clock arbors and such. If I was doing a large gas engine it would be inadequate.

 

[crueby]

Hi Bob, the loco is looking great, and that ship is amazing. I don't think that I would have the patience to do something like that.

TMS, sometimes I wish that I had a smaller lathe, when I'm turning parts down to 2mm dia on a large lathe I'm always thinking that I could do this better on a smaller machine.

Paul.

Thanks Paul, actually it is Chris, not Bob....

You are right about doing small bits on a bg machine, though anything is possible with the right setup i guess.

 

[Swifty]

Thanks Paul, actually it is Chris, not Bob....

You are right about doing small bits on a bg machine, though anything is possible with the right setup i guess.

Sorry about that Chris, don't know what made me think that your name was Bob, I've just woken up and sitting in bed with a cup of tea reading the forum, perhaps it's too early.

Paul.

 

[tms6401]

Thanks for being honest about the Sherlines. Your responses are somewhat what I expected. Perhaps a combination of the 9 x 20 I already have and perhaps a 15" Sherline lathe would work out OK.

I have the books for Heisler and Climax and I am deciding which I might have a chance of finishing.

Thanks Again, and now back to some excellent model engineering.

TMS

 

[crueby]

Sorry about that Chris, don't know what made me think that your name was Bob, I've just woken up and sitting in bed with a cup of tea reading the forum, perhaps it's too early.

Paul.

No problem, George!
Since I retired I don't need to make sense early in the morning anymore!!

 

[crueby]

I got the hubs for the wheels cut - simple cylinders, with a 2-56 hole tapped in one side to hold it into the soldering jig (the hub and all 8 spokes will have a screw holding them to the jig, which rests on the back of the rim for soldering). The extra-observant of you may notice that there are 9 sets of parts - am making up an extra wheel, just in case of problems doing the final machining/truing. If all 9 come out okay, then one will make a nice display piece (hang it on the back of the tender like a Jeep spare tire maybe??!)

For the spokes, took a length of rectangular bar and rounded one side on the sander. The spoke material is held in the machine vise, and using a dial indicator to get the length of cut, the spokes are cut off with a slitting saw.

The last photo is a shot of the test fit of the first batch of spokes with the first wheel. Got a close fit (took a few tries to get the correct length), so time to run off the spokes on the rest of the wheels.

 

[ausdier]

May be a little late now but how would this be for an idea.
If you are going to use a solid to start with, how about machining a recess where the spokes are to go and leave a thin piece on the back.
Silversolder or what ever you want to the spokes ( BLUE ) and then put the wheel back in the lathe and then face the back piece off ( GREEN ).
This has the advantages of not needing another piece of material for the hub, holding everything concentric and giving a flat surface for all the spokes to be clamped to.

Just an idea.

 

[crueby]

Ausier - interesting idea, though I'm not sure how I would cut the recess, at least in this case. The spokes are just 10mm long, and the recess would have to be about 12 or 13mm deep. It would take a special tool to get in there - in Kozo's book he mentions a 'trepanning' bit to do just that, and also mentions that it takes a lathe with a lot of power to use. I've never seen one, so dont get just how it works. I assume it would need to have clearances on both sides of the bit, and cut with the end, sort of a sideways cutoff tool? Anyone know how that works, can post some pics of that kind of tool?
I've done a simaler recess in a larger flywheel, but in that case the recess was a lot wider so I could get in with normal bits, switching between right and left handed ones to work my way down in steps.

So far, I've got all the spokes cut/fitted to the wheels, and am ready to drill/tap the back sides of them to hold them in the soldering jig - more photos to come soon on that.

 

[ausdier]

A picture is worth a thousand words, I hope.


Not all that hard and you only need clearance for the OD as you can see.
Just a bit of quarter inch tool steel.
Then whilst it is still setup, if the lathe can run backwards, you can also prep turn the flange using the same tool at the back.
If the lathe isn't powerful enough to cut the full face you can either thin down the whole tool or some people prefer to grind a groove in the middle of the face to reduce actual plunge cutting face and then just move side to side as you plunge in, at least this keeps the full thickness of the tool.
I hope this explains and is of some help to someone.
Cheers.

 

[crueby]

gotcha - thanks for the diagram!

 

[whitehedr]

Would an end mill in a cnc milling machine be able to cut that recess in the wheel blank?

ROG

 

[ausdier]

Yes and no.
An End Mill normally is designed to come in from the end or edge of the job and a Slot Mill ( Slot Drill ) is designed to cut down into the job and then move X or Y.
However these days they simply make just about all mills capable of plunging into the job.
The first picture provided shows an End Mill and you will see that if it was plunged into a job, it would not cut in the middle of the cutter. but the second picture shows how the cutting faces on the end of the Slot Mill act just like a drill, allowing it to plunge cut.

Yet like I said before most end mills now have their cutting ends all the way to the middle so can plunge cut.

Hope this was some help and wasn't too confusing.

PS here is a nice site I just found with some good info in it http://nikita.argia.net/kmaxon/safety/Q_stuff/1_cutting_tools.htm

 

[stuart123]

Would an end mill in a cnc milling machine be able to cut that recess in the wheel blank?

ROG

You could use an old style end mill in a CNC, but you would need to ramp down. Ramp angle up to 10 degree would be fine.

 

[Swifty]

I was thinking the same thing about ramping, however it's probably only be suitable for a CNC mill or a knee mill. It would most likely be too hard to bring the quill down on a bench top mill whilst cranking the table handle. It's very east to raise the table on a knee mill while cranking the table.

Paul.

 

[crueby]

Been an interesting few days - got the spokes made, and also the soldering jigs as Kozo describes. The jigs made soldering them up a breeze.

First step since last time was to put a notch in the back corners of the spokes - this notch is to hold the little length of silver solder wire in place for each end of the spokes. They were done up in batches, using an alignment jig made from a scrap of brass to line them all up in the vice,

where they were notched with an end mill.

The spokes and hub are all held in place with a sheet metal soldering jig, with holes at all the joints that both served to let me put the solder in, and also to keep the sheet metal from soldering itself to the wheel (had one wheel where the solder floated up on a bubble as the flux melted - had to break that one free like a sardine can lid, it will get faced off in the lathe in the next step anyway, so no harm done). There are also larger holes between the spokes to let the flame/heat through - they assembly is placed sheet metal up between two firebricks for soldering. The book gives all the dimensions for the jig, well worth the time to make up. I made 4 of them, drilled all together in a stack. That let me solder up all the wheels in two sessions.

Each piece is held in place with a 2-56 screw - meant a LOT of small holes to tap, did break a tap in one near the last piece, but was easy to drill out after heating it red with a torch and letting it air cool - that took the hardness out of the tap end so it would drill out easy.

After soldering, the back face of the wheels is faced off to thickness, and the steps in the spokes are also turned off.


Very happy with how they all soldered up - getting more comfortable with silver soldering with each piece.

Next step will be to face off the front of the wheels, bore for the axles, and finish turn the rims. The hubs/spokes will be painted, think I will put a little JB weld in the holes in the backs of the spokes first to smooth them out.

 

[SilverSanJuan]

Nice work. Silver soldering is fun isn't it?

Todd