View Full Version : Bridgeport Quill Feed Mod.

01-26-2009, 10:50 PM
My J head has no Upper Quill feed Gearing, or other Fragile bits (Cheapskate)

The only remaining parts are the Fwd/Reverse Gears and Overload Clutch, and Limit Stop assys.

Thinking of Using a Stepper or such to Replace all the Upper Gearing.

Would have Stepper Drive a Worm Gear on Input to Fwd/Rvs Quill Feed Section of Head.

Stepper would bolt to Head where existing Feed Rate Selector is now...

Not looking for CNC app due to all the Backlash, just want a Simple Variable Quill feed for Boring.

Do not know what speeds I need to shoot for, as I have none of the Gears to calculate the input shaft speed to Fwd/Rvs/Overload part of Head.

I imagine a reasonable Size Stepper (with basic Driver and Power Supply) would do. Steppers seem to fit the Size and shape needed.

Any Ideas?

01-26-2009, 11:31 PM
Why use a stepper? A simple DC gear head w/ a speed control and limit switches would do the same thing, no?

- Bart

01-27-2009, 01:55 AM
#1 Not knowing Speed required, Stepper will have a nice wide speed range. Final Speed Can be adjusted with Worm. I have looked around some, and have seen no Decent looking DC motors that are Small enough... Probably some Tiny Servos out there tho... But overkill/$$ for this app... Don't like Brushes near Oil/Grease either :)

#2 A nice Square box covering a Square hole looks better,

#3 Have not seen any Small enough, Strong enough Gear motors, that do not weigh 5+ pounds... The original Mechanical Limit stops will be fine, if I have enough Power to trip them.

Missed Steps do not matter as long as It does not Stall...

Trying to avoid Switches all over the place.

I could go with the Clunky CNC style Ball Screw Drive at Front of Quill... But I want a Manual worm driven Fine Feed too.

A simple 2~3 inch thick or so Square box over existing Square hole...