Re: TB5 proposal

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Ordered the cast iron for the heads today. Hope to have it soon.

Eric
 
Brass_Machine said:
Ordered the cast iron for the heads today. Hope to have it soon.

Eric

Few pics when ya get started, would be cool. I would like see how your tackling them.

Matt
 
Material should be here tomorrow. Hopefully I will get some done this weekend.
 
What parts did you decide to do Eric?
 
Great. Let us know if you have the brass and are doing the bushings as well. If you don't, someone else may volunteer.
 
The frames are progressing nicely.
Still have to drill and cut the second side, and make the outer bearing support.

And no broken milling bits (knock on wood) so far.

I have gotten better about trimming the pieces close to final size in the cutoff saw, and then making one or two light cuts with the mill to final size. There is an art to rough cutting and leaving just enough to finish off to final size.
I use to try and cut way too much in the milling machine, and the lathe too for that matter.

The angle for the frames is a good grade of mild steel, and very nice to cut.
Some steel can be on the tough side, depending on exactly what grade you get.

The method I am using is laying out holes where the radius in the frame are, and then drilling hole with a pilot and then a 1" drill bit. You need lots of cutting oil on those drill bits, and lots of ventilation, since the cutting oil lays out clouds of smoke.

One the holes are drilled, it is back to the cutoff saw to cut up to the edge of the holes, leaving a little extra. You have to hand-guide the cuttoff saw just before it breaks through to the edge of the round hole, else the blade will hit the side of the round hole and jam.

Then on to the mill, where the edges get cleaned up with a large long straight bit.

A little bit of de-burring is required between steps, with a file, to keep the razor sharp edged down to a minimum.






N0-21-Frames-01.jpg
 
On the bushings... I see they are to be reamed after they are in place on the frame. Since one of them requires an expensive piece of brass (.75") and the reaming requirements... maybe each builder should be responsible for their own bushings.

Thoughts?
 
I've suggested to Pat that the bushings be drilled (more under size than normal) and not reamed. Pat can install them in the frames, drill them in line and ream them, or the builder could do that.

Did you find the brass in the scrap box Eric?
 
OK - I got the bushings. I'll drill them under but won't ream.
 
I have the brass Pat - no problem. I got some CNC ends that will work.
 
I have enough to do the smaller bushing and the exhaust pipe.

What other parts are missing? Who is doing what now?
 
No one has claimed the springs.

> I think each builder should supply their own spring.

I assume everyone has some packing material for the rod.

>probably correct

I will probably do the pistons and rings.

> for a good piston to cylinder fit, that's probably essential

You guys want turned rings?

> or o-rings maybe?

Is everyone going to paint their own frame/cylinder?

> Sounds like the way to go



 
The minor stuff can be left to each build such as paint etc. I may not want mine painted the same color. :big:
 
The frame is starting to look like a frame.

Note: You need a large wrench or clamp on the frame to keep it from automatically rotating into the bit when you are making the round part in the mill. Don't try and hold the piece in your hand, you cannot.

Also, you have to rotate the work into the bit, ie: looking down on the mill table, if the milling bit is rotating clockwise, the piece has to be rotated clockwise also, or else the bit will ride into the work, and again, probably break the bit.

Luckily I had read about this previously or I would have broken off the bit.



No-21-Frame-01.jpg


No-21-Frame-02.jpg
 

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