Re: [CAD_CAM_EDM_DRO] Calculating mechanical forces

In a message dated 8/1/2005 11:05:01 PM Eastern Daylight Time,
elson@... writes:

Think your round ways and linear bearings can keep the
machine within it's tolerances with 332 Lbs of force? Well, maybe you
have a
smaller motor.

Jon



Jon:

For years we ran round Thompson type bearings and ways on our CNC routers
with 12 to 15 Horsepower motors, turning 20,000 rpm and cutting thru wood,
particle board, fiberboard etc. at speeds up to 400 inches per minute. We held
+/- 0.001" tolerance with no problems on materials where you could measure
that close. I think round bearings and ways would work just fine with a very
small motor like most mills run. Plus, the cutting speeds are also slow.

Now we use, for the most part, pre-loaded THK type bearings because we can
use much smaller ones and get the same tolerance. Just for info, the round
bearings and ways were between 3/4" and 1-1/2" diameter, depending upon the size
of the table. Smallest table sizes were about 36" X 36" Larger ones were
49" X 106" and the table moved for all cutting in the X and Y directions on
these older machines.

I hope this will help, Oh by the way, I think your figures are good and JJ
could use those for a base for his own.

Randy Abernathy
4626 Old Stilesboro Road NW
Acworth, GA 30101-4066
Phone / Fax: 770-974-5295
E-mail: cnc002@...

I furnish technical support, repair, and other related services for your
industrial woodworking machinery. My background as Senior Service Engineer for
the SCMI Group for nearly fifteen years with factory training, combines with
my extensive background in electronics, mechanics, pneumatics, electrical and
CNC machinery to offer you needed support for your machinery.


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