View Full Version : Mill table power feed

01-14-2010, 02:40 PM
Hi All, I have never worked or seen closely any of the power feed units (ones that you can buy and install yourself) that are used on mill tables and would like to know how the feed speed (IPM) is set (must depend on the TPI of the threaded rod) and marked on the units' dials. Thanks. DavidH.

01-14-2010, 03:56 PM
I can't say for other units but mine had no markings for feed speed. I calibrated a few of the main speeds I use with a stopwatch and the DRO and marked them on the body of the unit. Generaly though, I just calculate the cutting speed and go with a feed speed that the mill is happy with. It will let you know.

01-14-2010, 05:04 PM
i too just run it at the speed it "feels good" at. mine is on a bridgeport and im am a extreme novice at milling stuff. . . but its soooo much easier than cranking the handles. . . . .
(the other davidh) (no caps)

01-14-2010, 06:08 PM
I'd say the slower the better. Most table feeds run too fast. You really need the torque at the lower end of the speed range.


01-14-2010, 07:01 PM
Thanks for all the info. I was wondering if there were dials on the power feed units to set the speed or like dockrat mentioned, one needs to caliberate and mark their own. DavidH

Your Old Dog
01-14-2010, 08:35 PM
I have the $250 wonder on mine and I just increase the speed till the mill starts to sound like it's working and then back it off a tad. I don't think you can really calibrate them to IPM because the gibs are constantly being readjusted.

01-14-2010, 10:11 PM
(must depend on the TPI of the threaded rod) and marked on the units' dials.

If you mean the leadscrew of the mill table, I don't think it has a bearing on the speed. That being said, I have one of the NON Servo brands that, although it was a bit of a troublechild during install on a 9/16" dia. leadscrew, has performed satisfactorily.

01-14-2010, 10:51 PM
Hmmm.... I just go by the feed rate readout on my DRO. :o

01-15-2010, 12:45 AM
It does depend on the pitch of the leadscrew. A given drive RPM will result in different feed rates with different pitch values. That's probably one reason the dials aren't calibrated. Another is that the speed controls (at least on the budget units) are not sensor/feedback equipped so it would be a swag at best.

01-15-2010, 04:36 AM
Divide the revs of the motor by the pitch of the leadscrew that would give you feed per minute.
EXample--- input revs to leadscrew 60
leadscrew pitch-------------- 5 TPI
60divide by 5 = 12" PER MIN.