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PM Research Mini Engine Lathe Build

Thanks Tony. I'll check out that tapered gib mod and see if I can get it done on mine. I have to keep tightening up the screws under the apron to try and keep slop out, and their not easy to get to. I'd also like to make a compound slide eliminator post block. If I do I might also get the next size up on the QCTP, and use an AXA just for that purpose. The OXA has been fine, but I can't use the larger tooling. I also have a treadmill motor to install at some point. It will really help out when I need to use slower rpm's as well as larger tooling. Or maybe just a bigger lathe at some point 🤔. But that will have to wait for while. I see you also have a carrage lock and I really need to get that done on mine as well.
 

TonyHallo

150cc
I don't know what size mine is but will hold 1/2" tool. I run my lathe at 400 rpm just about for everything, rarely do I change speeds. I would think your lathe already has a carriage lock, I just added a bolt so I didn't need to use an allen wrench.
 
I've been running about 500 rpm. I did try some carbide on my lathe at 800rpm and .030 cuts, witch it did just fine with a nice finish. For removing a lot of material fast, it worked out pretty well. I built a couple of X axis locks for my mill, I'll get a pic of that soon. I did get more work done on the handwheels. Handles are finished up and I got the square holes in the middle done.
 

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TonyHallo

150cc
I sent it you in a conversation, I would image it is copywrite.
I used brass bars from McMaster Carr, 1/4" x 6" and 3/8" X 6". when the angle was milled the the bars warped as the outer skin was removed. Took some time messing with them taking alternate cuts. If I knew then I would have bought 1/2" and 5/8" diameter bronze bars and milled it into the tapered gibs. The brass bars are extruded and have stresses while the bronze is simply cast.
I used 3/4" x 1" steel bar to make the gib support brackets. On the 9" I was able to use a 14"-28 thread for the adjusting screws rather the 10-32 shown in the article.
Both of the adjusters are on the headstock side of the lathe while the article has them on the tailstock end. This is because the carriage lock is on the tailstock side and I did not care to eliminate it.
 
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Don't have my parallel bars yet, so I had to make up a jug for dusting off the lathe bed. It's not at speck yet, so there's a lot more to do, but I have some parallel surfaces to work with.
 

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dhal22

GSN Sponsor Tier 1
While you're way down on the forum site (off topic) check in on the 9 year old beer thread. Should anyone here drink beer.
 
Got some of the headstock work done on the lathe today. I've been enjoying it so far. Once I got the gears and shaft done, the gears are a press fit onto the shaft.
 

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