Power Feed for Lathe Apron - proof of concept

[jlmanatee]

Continuing the saga of my Grizzly G4000 lathe powerfeed problems, I've rigged up a belt drive for the apron handwheel. I replaced the handwheel with a 120T timing belt pulley and attached a small DC worm gear motor with a 15T timing belt pulley and belt. I'm driving the motor with a 12v power supply and a reversible variable speed controller. With this setup, I can drive the apron from 0 to 11 ipm. The picture below is a 10 thou cut of questionable steel (maybe hr) at 660 rpm and a feed rate of 6 ipm using a poorly ground HHS bit.

 

[brino]

Interesting idea!
I'd like to see more.

Like results with a properly ground bit, and maybe video.

Thanks for sharing this.
-brino

EDIT: Also, I must have missed something..... the Grizzly site shows a thread chart for the G4000,
it also says:

Longitudinal feeds: (4) 0.0047–0.0120 in./rev.

so it must have "factory" power feed.
There must be some history here that I haven't seen......

 

[jlmanatee]

Yeah, the apron power feed mechanism in my G4000 was a lemon and by the time I ended up with all the mods to my lathe, it was really too late to complain to Grizzly. The half nut mechanism for threading seems to work fine and is separate from the worm gear/wheel mechanism that drives the power feed. My worm eats worm wheels for breakfast, just grinding them to dust. The alternative is for me to totally replace the entire apron casting and other parts. This was fun-ner.

 

[rbertalotto]

Check out how I used a school bus windshield wiper motor to power my lead screw

Power Feed Modification on JET 12X36 Lathe | RVB Precision

I have a JET 12 X 36 BD lathe of 1985 vintage. It a wonderful lathe for the type of work I do. Mostly hobby gunsmithing and making various parts for motorcycles and expedition vehicles. When I bought the lathe in 1995 it was box stock. It had been used in the Borden Pasta factoryRead More

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