Milling Machine Power-Feed Attachment
I thought this power-feed attachment that I fabricated for my Emco FB-2 vertical mill might interest you. I bought the FB-2 many years ago when it was still in production. I have been very pleased with this mill over the years, however the one short-coming was the fact that I did not purchase the optional power-feed-attachement, because at the time, they were asking a 1/3rd of the cost of the mill for the power-feed-attachment. Later on, it became impossible to purchase one. One day while browsing the surplus section in Princess-Auto, I noticed a surplus 110 volt gear-head motor. I decided that it had its possibilities and purchased it. After a fair amount of work, I came up with a power-feed assembly that powers the table longitudinally at a speed of 1.250 inches of travel per minute. For quick traverse, I dis-engage the drive and run the table in the direction that I wish manually. Now it would have been nice to have a gear box like the factory unit that had 4 speed selections, however I am pleased with how my home-built power-feed-assembly worked out, and the cost was right.
The above photos of the table showing my power-feed assembly on the left end of the table along with the limit switch and adjustable stops. This on the table limit switch design eliminates damage to the lead screw if a hard stop is encountered. This limit switch is coolant proof, oil proof and protected from chips.
In this photo, you see the means of engaging and dis-engaging the power-feed from the table feed-screw. When giving thought as to how I would accomplish this, I came up with the idea of removing the output shaft from the gear-box main drive gear, located in the gearbox. I made up a new output-shaft that was increased in length, so that the output shaft now exits out the gear-box on both ends of the case. To allow this to happen, I bored a hole in the case at the opposite end, from the output-shaft. The protruding shaft end has a knob installed, allowing for the output-shaft to slide back and forth, and the drive-dogs to be picked up by the brass adapter that I machined for the end of the lead-screw, located in the milling machine table. I should add that I machined a slot in the output shaft, and made the output shaft a sliding fit in the main drive gear. I also installed a drive-pin through the hub of the main-drive-gear that rides in the slot that I machined in the output-shaft, allowing the output shaft to be driven by the main gear, but I can now engage and disengage the drive when required. The motor is reversible with the toggle switch shown on the control box. The indicator-lights show the direction of travel.
Last edited by Jerry; 03-03-2010 at 12:57 AM.
Pretty cool Jerry. I wonder if you can just vary the voltage to the motor to get different speeds. I have a similar one started that I've been working on, on and off for a while, for a much smaller mini-mill. Gear headed motor from an 18 VDC cordless drill and an old model rail power pack. Not very sexy, but it should work.
No on the variable-speed, but at the end of the day, and having used this power-feed as you see it for some years now, I am pleased with the speed that I choose, as it has proven to be a good speed to achieve a nice finish, and I am able to remove a good amount of material at the same time if required.
Originally Posted by knudsen
Last edited by Jerry; 03-03-2010 at 09:17 AM.