My adventures while making a motorized x-axis feed for my Rong Fu mill

[Charles scozzari]

That's always a fair point, and my experience may not be representative of others. In my experience, "what I usually do" doesn't seem to matter to my new projects, which are always defying my well-laid (hah!) plans. When cutting those very long pieces, I usually end up pulling the vise to maximize table support (or at least minimize the amount of cruft I need to build up to support the work at the extents of the table). YMMV, and if you ask 10 machinists how they'd do something you'll get 11 answers - so who knows? But I do try to keep my options open, and the handle forecloses one.

GsT

Im the same way. Everything I do differs from the previous job. I do mostly 1 Off stuff for car guys or make some sort of tool and like you said everyone has there way of doing the same thing. I sometimes can't understand how I see things are made to look so difficult but that's the decision of the individual. Anyway have a Merry Christmas and a healthy, Great New year.

 

[ARC-170]

Regarding the handle: it can be removed if needed. I'm using a 1/4-20 stud to hold it on. The shifter block will sit below the table.

 

[ARC-170]

Motor Discussion
I'm trying to narrow down the motor parameters to make it easier to pick a motor.

The fastest I can turn the handle by hand is 36 revolutions in 10 seconds. That's 216 RPM.
The lead screw is 11 TPI (I think). I made 10 turns in one inch. It's probably metric.
That means I can turn it 21.6 inches per minute.
Therefore, it seems I need a motor capable of turning at least 200 RPM or so, preferably faster if I want a rapid traverse.

 

[ARC-170]

MOTOR DISCUSSION
Motor #5
It would seem that the motors like #4 (3 connection bosses) don't come in anything above 100 RPM in 12V. I found a 150RPM in 24V. The other style like #3 (box with 4 connection holes) are usually lower torque, BUT I found one that might work. It's a bigger one (the box is 58mm x 82mm). It would be $95 shipped:



Here are the specs. I'm thinking of getting the 190RPM, 2A, 20 kg-cm one.


Thoughts and comments?

POWER ADAPTER
Once I have the motor picked, then I'll figure out which power adapter to get. Will this one work:


I would need to strip the wires to connect them to the speed controller.

 

[RaisedByWolves]

Motor Discussion
I'm trying to narrow down the motor parameters to make it easier to pick a motor.

The fastest I can turn the handle by hand is 36 revolutions in 10 seconds. That's 216 RPM.
The lead screw is 11 TPI (I think). I made 10 turns in one inch. It's probably metric.
That means I can turn it 21.6 inches per minute.
Therefore, it seems I need a motor capable of turning at least 200 RPM or so, preferably faster if I want a rapid traverse.

Refresh my memory here, what machine is this? Link?

Many of the motors you listed so far seem to be too small.

#4 might be a contender depending on the size of your mill, but let’s clear up what machine we’re dealing with before going forward.

I have the LMS/MicroMark drive for my mill and I can tell you the motor and power supply are substantial.

My PS is 24V @ 10A and turns a measured 240RPM max.

You CAN over drive a DC motor for your rapid travel, the question is how much, for how long and under what conditions.

 

[ARC-170]

Refresh my memory here, what machine is this? Link?

Many of the motors you listed so far seem to be too small.

#4 might be a contender depending on the size of your mill, but let’s clear up what machine we’re dealing with before going forward.

I have the LMS/MicroMark drive for my mill and I can tell you the motor and power supply are substantial.

My PS is 24V @ 10A and turns a measured 240RPM max.

You CAN over drive a DC motor for your rapid travel, the question is how much, for how long and under what conditions.

Rong-Fu RF-30/31 clone. Table is approximately 8" x 29".

In post #3 I measured the torque needed: 10-16 kg-cm. It was suggested I get something with twice that, so 20-32 kg-cm.

The fastest I could turn this by hand was about 200 RPM. Most of the "RPM under load" specs were half of the "no load" specs. But, the torque wasn't enough on anything in the 400 RPM range. Rapid traverse is not as important to me as having enough power to make a cut.

 

[RaisedByWolves]

Rong-Fu RF-30/31 clone. Table is approximately 8" x 29".

In post #3 I measured the torque needed: 10-16 kg-cm. It was suggested I get something with twice that, so 20-32 kg-cm.

The fastest I could turn this by hand was about 200 RPM. Most of the "RPM under load" specs were half of the "no load" specs. But, the torque wasn't enough on anything in the 400 RPM range. Rapid traverse is not as important to me as having enough power to make a cut.

Ok, I had to look that up and for sure, the class of motor you’re looking at is miniscule for that machine.

You need something more like a servo drive, aka a Bridgeport size drive.

 

[ARC-170]

Ok, I had to look that up and for sure, the class of motor you’re looking at is miniscule for that machine.

You need something more like a servo drive, aka a Bridgeport size drive.

I looked up the specs for the power feeds for these machines: minimum was 150 in-lbs (173 kg-cm). Most were 450 (518 kg-cm), and the max was 780 in-lbs (864 kg-cm).

I'm gonna have to rethink this!

 

[Charles scozzari]

Evan a gear motor set-up to get done But like I said before mate a Bridgeport feed. you can possibly lay it on its side as I did in the photo and lower it and you'll have crossed all the Ts and dotted the i.

 

[ARC-170]

Evan a gear motor set-up to get done But like I said before mate a Bridgeport feed. you can possibly lay it on its side as I did in the photo and lower it and you'll have crossed all the Ts and dotted the i.

I have a motor drive like the one in post #13. It's a Vevor one. I can't get it to work. The first time it died, there was a loose solder. I got it working again, then it died. I took it apart. It appeared to be a loose wire connection on the rapid feed button. It only seems to work sometimes; I can get it to rapid traverse, but it's hit or miss on whether or not it will travel at normal speed. It will move a little, then stop. I can still push the button for rapid traverse, though.

The motors I've seen that have enough power cost a fortune. I may just buy a new power feed from a more reputable company.

Another thought is to use a motor with a belt. The gears on the one I have use a 6-tooth gear to drive a 106-tooth gear.