One is always living in fear of one of the plastic gears in the mini-mill
breaking. The procedure for changing the gears is somewhat tricky and as far
as I can tell involves the expense of $25 for a set of new gears (they
recommend changing all even if only one breaks) and a $70 kit to effect the
change (reusable with each change).
OTOH the Little Machine Shop sells a kit whereby the mill is converted to a
belt drive. This is a bolt-on procedure taking 20 minutes (to quote LMS).
The cost: $130.
I am seriously considering this option but would like to know if anyone else
has attempted this and what results they had. Are there any cons to doing
I converted to the Little Machine Shop belt drive and it was well worth it.
I purchased it when I broke one of the original plastic gears so I was going
to have to spend some money and tear into it anyway.
Here's an online review of it:
In regard to your other message about grease for the gears my recommendation
would be that you order the belt drive conversion kit so that you have it
handy when needed and just run the gears with the grease that came on them
until you have a problem. I would also recommend you adjust them to
minimize the noise and (hopefully) wear and tear too though. You'll find
the procedure on pages 15-16 of the Minimill Users Guide from Little Machine
If you order the belt kit from them you might want to order an extra belt or
two at the same time. They're not expensive but they're difficult to find
and I've been through 2 of them already. The first was because I didn't
tighten the pulley well enough on the motor shaft so it slipped down and cut
into the edge of the belt. The 2nd was because I was working it WAY harder
than the minimill is intended to work so I consider myself fortunate that
all that I screwed up was the belt. :-)
And they're definitely more expensive if you have to order them separately
and pay shipping.
One other thing you might want to order from them is brushes for the motor.
Mine quit working one day and when I removed the brushes I found that one of
the springs was discolored in one area and had lost much of its tension
there. I've had that happen on a few Chinese motors from overheating.
"I'm not grown up enough to be so old!"