Atlas 7B Disassembly and Teardown! Pic Heavy!

frugalguido said:
My crank pin was broken too and was repaired before in the weld area, guess what, it was broken again, so I remade the whole assy. On the new one I press fitted the pin then TIG welded, hopefully it won't break like the original.
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Excellent work! Very nice! I like the solid brass block as well. I may have to commission you to make me one! ;)

On my shaper I finally finished washing all the internal parts! They cleaned up quite nicely.

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I still have to do the ram, the column and all the external brackets/pulleys, but all the internal grease covered parts are done.

I also bought a piece of brass to make the spacer I'm missing. It's supposed to be 2-1/4" round but I found a small square of the right material on eBay that's 2-1/8" square. I think it'll work. I'm not sure if I'll turn it down to 2-1/8" round or maybe just take it to 2-1/4" and it'll be like a square with rounded corners.

I'll get the column cleaned up in next day or so and begin re-assembly. I'm thinking of picking up some assembly lube for all the new parts. It's probably not necessary but it should stay in place better than a 10 weight oil. It will likely take a few days to get the whole thing back together. I'm going to have to fix small issues as I go. There's small things like set screw marring on shafts and teeth marks here and there from pliers or pipe wrenches and the like. I'll do my best to file that stuff down for easy assembly.
 
If I remember right the block I made was from aluminum bronze. Check inside slide surfaces of the crank arm for wear and grooves, mine had a lot of wear in the center, I had to surface grind the area and then made the block to fit.
 
Right on. I'll check into it. Maybe that's why my block had brass applied to it. Build up a little material and grind down to size.
 
@frugalguido nice weld by the way! If you used any filler what kind did you use? I've got a post over in the welding section about this very problem. I'm looking for opinions on the best filler for this.
 
ER-70 probably, I remade the whole assy, pin and all, for one, I didn't know what type of weld filler was used in the previous repair, it looked like crap, 2nd by the time I removed and chamfered the previous weld area, everything would be pretty thin. 3rd, the brass washer had worn the other side and the main piece was warped from heat. I always questioned the design, seemed weak only about 1/4" thickness at best supporting the pin and the pin is under high load. Seeing yours broken proved my thought. Look at the heat used in the old one!
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The heat might possibly be from a preheat? Most seem to recommend a preheat and slow cooling for welding high carbon tool steels.

But yeah, the design is not great. I'm trying to remember why the backside it relieved like it is. Maybe you could machine a pin with a flange on it, like a top hat and weld that flange? Might take some strain off the weld.
 
I think the recess is for the stroke length adjusting screw assy. Well, if the discoloration was from preheat it didn't work!
 
Quick update on this project. I kinda stalled out for a few days on the reassembly because I want to have the oil on hand when I put all the pieces together. I thought about using a separate assembly lube but decided to just use the normal lubricating oil.

I had a heck of a time trying to track down some ISO 32 way oil in a one gallon size. Ultimately I failed to find it so I went with an ISO 68 way oil from Renewable Lubricants. Hopefully it'll arrive next week.

In the mean time I have a few other things to work on. I got some special filler metal to give me the best chance at welding the pin onto the plate from a few posts ago. I can also turn that brass spacer that I was missing.
 
frugalguido said:
I made a lot of the same parts that you found worn or broken. But it gave me an opportunity to improve them.
The sliding block,
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Hey where do the side oil holes connect to? Do they run up into the semi circular "dish" on the top of the block? I'm thinking about adding them on my block like you did.
 
Welded the pin today!

I gave it a decent groove and filled it up with TIG and Hastelloy-W filler. Clamped it all down with heat sinks and such.

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For the welding I changed the spring clamps out for vice grips.

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There's no discernable warping.

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