Bridgeport J (step) head motor upgrade?

gsondubs · Oct 29, 2017

Hello everyone

I'm new to machining, purchased an older BP J step head w/1 hp motor. I have been doing research to see if it is possible to install a 2 hp motor onto it. I've that I will need to look for a C face motor, an adopter plate, extend the shaft and bore out the step pully.

I want to see if anyone had done this and if you have any pictures to share? I am very curious on what Motor I need for this conversion. Model number?

(I do have 3ph power)

Thanks in advance

Ray Behner · Oct 29, 2017

This is what I have on my Chevalier. First, you take all the old drive components out and put in new motor and two belts. Hook up the electric and use the machine. This is mine completed:
http://www.practicalmachinist.com/vb/general/new-drive-motor-installed-my-chevalier-295410/

Mine is single phase, but here's the same thing only 3ph.
VARIABLE FREQUENCY DRIVE PLUS, PN M-P-3-23

rons · Oct 30, 2017

It's possible but why. Just to have more horsepower. When you start taking real heavy cuts on a BP model like yours the whole thing will shake and vibrate unless you have it bolted to the floor.

No offense gsondubs, but I have seen it happen. You are fortunate if you have real 3 phase power available.

TDegenhart · Oct 30, 2017

Those machines were not designed for heavy hp. If you do need more than what the BP will provide, get a heavier machine.

Tom

comstockfriend · Oct 30, 2017

gsondubs said:
Hello everyone

I'm new to machining, purchased an older BP J step head w/1 hp motor. I have been doing research to see if it is possible to install a 2 hp motor onto it.

Yes, why??? You're new to machining, you need to play around with the machine doing machining, not changing motors out.

John

lr harner · Oct 30, 2017

only "upgrade motor" i coudl see being usefull would be a 3500rpm motor if you mostly ran sub 1/2 inch mills and or carbide. i didnt know they came like this right from BP. as luck woudl have it i got one not knowing and so glad i did. i do mostly knife work and other small things and find the extra speed nice. i think if you have the 1700rpm motor you can still over drive it with a VFD to cheat more rpms

fastone53w · Oct 30, 2017

I have old J head step pulley 1hp pancake motor mill. Had it mill scraped and refurbished about 12 to 15 years ago. I have never yet ran out of HP on it or came close to. I run it on buzz box to get 3phase. so I really only have about 7/8hp if that.. You will be fine with what you have.

I also have 2hp variable speed Bridgeport that had refurbished about 10 years ago. When it comes time to sell one I will be keeping the step pulley machine. It is my favorite out of the two.

Search

Largest Manufacturing Technology Community on the Web

Search

Bridgeport J (step) head motor upgrade?

gsondubs

Plastic

Ray Behner

Diamond

rons

Diamond

TDegenhart

Diamond

comstockfriend

Hot Rolled

lr harner

Aluminum

fastone53w

Aluminum

Similar threads