NEWLY-ACQUIRED JET 1236PS

[LouStule]

A friend of mine, doing what you are attempting but in reverse...cut a hole in the roof of his house - attic floor..into the living room...through the living room floor straight into the basement...and dropped the equipment down with a crane.

Obviously, he's not married. Or, not married anymore!

[Bill Shields]

actually he was and remained married until his passing a few years ago.

used excuse of his wife going away to 'visit family for a week' to 'repaint living room and put down new carpet' while she was gone.

she chose all of the colors ahead of time so was very pleased with the work upon her return.

I lost touch with her when I moved in 1977, so I never found out how she dealt with the machinery in the basement.

is why I have a ground level entrance to my basement / shop...

[GlennW]

I remember seeing images of the machine being lowered through the hole in the roof/house.

[Steggy]

I remember seeing images of the machine being lowered through the hole in the roof/house.

The true hobbyist always finds a way to get it done—even if it means hoisting machinery through the roof.

[Steggy]

I gotta say one thing. The folks in Taiwan who built this machine have strange ideas about electric motors...Ergo I'm going to work out how to re-power the unit with a motor that doesn't weigh a ton, take up the space of a EMD prime mover and suck up juice like an arc welder.

Your lathe looks like a very functional machine for your shop.
Enjoy making things with it!
RussN

Thanks! It's undergoing an "engine swap" as we speak, so to speak. Out with the old single-phase boat-anchor motor and in with modern three-phase power. I actually was planning to do this some time in the future, but a good deal on the new motor came along and I decided to get 'er done now. A VFD will be next. I'll have some photos at some point.

The "engine swap" is done and after I had monkey-rigged some temporary wiring, I was able to test-run the lathe. The machine is noticeably quieter and smoother with the new motor. Next step will be to acquire a VFD so I can kiss goodbye to having to fool around with V-belts to change speeds.

OEM Motor & Power Transmission Assembly

OEM Motor & Power Transmission Parts Removed

New Motor Mounted on Lathe

New Motor Ready for Test

Testing Lathe

[Bill Shields]

BE CAREFUL with a VFD and running at speeds more than 30% off 'standard rpm.

motors can get very hot...

[Steggy]

BE CAREFUL with a VFD and running at speeds more than 30% off 'standard rpm.

motors can get very hot...

That is why I purchased a high-quality, inverter-rated motor. The particular motor I have has a 10:1 speed rating, and can be continuously run at up to 50 percent over nominal rated speed (1750 RPM), which works out to 2625 RPM. Minimum recommended RPM is 275.

[Bill Shields]

Cool.. well worth the $

[Steggy]

Cool.. well worth the $

Well, as you know, you only get what you pay for.

That said, it was an open-box, excess inventory motor, never run and never installed. I got it at a very friendly price.

[Steggy]

I have completed the lathe's installation (other than the VFD) and have started the first project, which is to finish-machine the collet chuck backing plate. Before machining the plate, I did some aimless turning on a hunk of CF 1018 just to get a feel for the controls and also to see how much of a bite I can comfortably take in one pass. I did some cuts on the 1018 using a carbide, and also with an HSS tool. The HSS tool had no problem with 0.100" bites per pass. The carbide easily handled 0.120" bites, although I could tell from the machine's sound that it was working fairly hard with that much of a bite.

Next I tried some single-point threading, something that I have done many times in past days when I used to build drag cars and needed to make odd pieces of linkage and such. I use the "traditional" technique of setting the compound to 29.5° and using the compound to feed the tool instead of the cross-slide, only using the cross-slide to retract the tool to return to the start. As I had turned the CF 1018 bar to 0.750", I decided to cut a 16 TPI thread using an HSS tool, which produced pretty clean results. A 3/4"-16 nut threaded on with just a hint of slop. So far, so good.

Before continuing, I should mention the cross-slide feed is 1:1, meaning 0.001" on the collar moves the tool 0.001". Not a big deal—when I first learned how to operate a lathe some 60 years ago that was common. However, most of the lathes I have used in the more recent past were 2:1, and my head must have been stuck on that as I was working on the backing plate.

The chuck's register bore is 2.734". As produced, the backing plate's register was 2.830". So I lightly faced it and was able to close in to the desired diameter plus 0.005". Cool! I'll take 0.004" off and I'll likely have a light interference fit. So, forgetting the cross-slide is 1:1, I dialed the tool in 0.004", not 0.002" like I should have done. Of course, I didn't see my mistake until I went to put the chuck on the plate and felt a teensy bit of slop. I had succeeded in converting the backing plate into a paper weight. Well, not totally a paper weight: there's enough meat for me to face off the existing register and make a new one, which I will do. However, I ordered another backing plate...just in case!

On the plus side, the finish on the backing plate's face is very smooth. Maybe I'll just polish it real good with crocus and oil, hang it over the sink in the head and use it as a mirror.

[Russ Hanscom]

Add some adjusting screws and make a set-true type backing plate. All is not lost yet.

[Harold_V]

One may also be able to insert a thin sleeve, depending on the remaining material. Picture?

H