View Full Version : Harbor Freight MicroMill - My Journey from Manual to CNC retrofit.......


jeffo2001
07-02-2007, 09:23 AM
I bought a MicroMill (X1) from Harbor Freight several months ago
with the intentions of converting it to cnc. So far, I've finished the
design, have all the purchased parts in-hand and am currently using the mill
to manually make the parts I need for retrofit.

Unfortunately, I've spent about half the time replacing/repairing and upgrading
the mill so I can make the parts I need for retrofit. First thing that went out
on me was the DC motor control. I blew about 5 fuses on the first part alone. (Usually when drilling larger dia. holes.) Finally the whole board went out on
me!!!! So I replaced with a Bodine 835 DC Control I found on ebay. Man this thing is great !!!! Much more torque from the 1/5hp stock motor now.

However, more reliable torque from the motor put too much stress on the spindle gears.......those damn plastic spindle gears are awful!!!!!
I'm on my 2nd set of gears now and they just lost a few teeth!!!! So I guess I need to upgrade this part of the mill next.

Has anyone done this? Any suggestions????? Should I just replace the plastic
gears with steel ones?? Would a belt drive spindle be better??? Should I go ahead and upgrade the entire spindle assembly??? (I'd hate to improve the gears then have the bearings or spindle go out on me next....)

So I would like to fix this problem without it snowballing to the next component!!!! Any input from you guys would be greatly appreciated!!!!!

Jeff

twocik
07-02-2007, 12:47 PM
ON the new DC controller, does it have a reverse and forward switch? I'd like to see a few pictures if possible... :)


I've recently CNC'd my X1, and have been looking at different solutions for a different gear/belt drive.

jeffo2001
07-02-2007, 02:13 PM
twocik,
It's a std Bodine 835 DC motor control. You can go to their website and look under dc controls. They have pics and specs...I don't have any.

Jeff

Stepper Monkey
07-02-2007, 08:27 PM
Has anyone done this? Any suggestions????? Should I just replace the plastic
gears with steel ones?? Would a belt drive spindle be better??? Should I go ahead and upgrade the entire spindle assembly??? (I'd hate to improve the gears then have the bearings or spindle go out on me next....)

So I would like to fix this problem without it snowballing to the next component!!!! Any input from you guys would be greatly appreciated!!!!!

Jeff

You have an X1, the problems will snowball. More torque may have stripped the gears, and you are correct that if you solve that you will put more stresses into the spindle, but that isn't actually the big worry - The Z will cam and seize randomly during movement from the greater forces applied to the headstock. Should that get solved the torque will then cause the column to flex like a bendy straw and start screwing up and breaking tooling. Replace that and you are now down to what original parts? The crappy XY table?

If you are planning any serious work, get a bigger machine if you can. Even if your time is not valuable to you and you have and endless supply of Tylenol, just cost-wise it'd still be just plain cheaper in the end to go bigger. Sorry I don't have better news.

If you want to save what you've got, a belt drive does solve a lot of headaches. Then baby the machine and it should work fine. Don't expect it to cut anything you wouldn't do with a Dremel though.

jeffo2001
07-03-2007, 08:00 AM
StepperMonkey,
Thanks for the reply. Sounds like we are thinking the same thing.....;)

Unfortunately, I don't currently have the budget to go bigger. So for
now, I'll just remedy the little things as I go along.......and stock up
on asprin. The good thing is, I'm planning on using the mill to cut mostly
plastic (UHMW, Nylon, Delrin) once it is cnc'd.

I think I'll just consider this as a great learning experience......:rainfro:

Know of a good source for belt-drive components?

Jeff