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