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View Full Version : Belt or Gear Mill



seajays2
03-03-2005, 01:57 PM
Any pro's and cons for either?
John

tattoomike68
03-03-2005, 02:35 PM
the variable speed is nice that you can speed up or slow down during the cut,(like a chattering borring bar you can slow it down and get it to stop chattering.)

belt drive is fine too, it just takes a few second to change speeds.(olny 8 speeds)

I would go for the variable speed if I could.

sch
03-03-2005, 02:39 PM
Depends on how you like to use your time.
Gear heads are noisy but easy to change
speeds on. Belt drives are quieter, but
a real PITA to change speeds on. Your
PITA coefficient may vary and it helps to
get cogged belts. Resonance vibrato can
be more of a problem with belt drive.
Square column is worth the $300-500 differential in price over round column.
You get a few more speeds with belt drive
which sometimes is useful. 3ph /VFD conversion with belt is easy but doesn't completely get rid of the need to change
the belt position at extremes of speed change. If you don't change setups alot
then these are lesser considerations.
But if you face mill, plunge or edge mill
then drill some holes and tap you will be
changing setups a lot. Changing belt speeds
is a lot more trouble than say a Bridgeport type. Steve

precisionworks
03-03-2005, 03:33 PM
Maybe I'll live long enough to get a gearhead or VS mill. When the belts are set to 1500RPM to drill a tiny hole, you have to flip them to tap at 150RPM, which means removing & repositioning both belts. A stool or short ladder is required. My hands get pinched most every time, but still have ten fingers, so far. Under really heavy loading (drill & tap 3/4" thick HRS with a 3/4"NC tap) belts will slip unless VERY tight. Yadda, yadda, yadda.

Any guess what my next machine will have?

JRouche
03-03-2005, 03:55 PM
I like a mill with back gear and belt drive with a three phase AC motor being driven by an A/C drive or variable frequency drive for speed control. Just like my Bridgy 2J.

So for me I guess gears and belts http://bbs.homeshopmachinist.net//biggrin.gif

If not the VFD then at least the back gear and variable sheave pulley with belts.

JRouche

Dr. Rob
03-04-2005, 01:04 AM
Quiet, quiet, quiet. Just did a conversion project for my mill, from gear to belt. Shhh.