RE: [CAD_CAM_EDM_DRO] Re: Acceleration rates..

Just a few words on acceleration rates...a different perpective...

Consider when you want to pass through a corner without stopping.
That corner will be rounded to a particular radius, and that radius
will be the square of the end effector speed divided by the accel.

An example might be a cnc router going at a path rate of 4 inches per
second.
Let's say you have available 0.1g. That is about 38 inches /sec^2.

The minimum radius at that speed is simply 4*4/38=0.42 in!

At 1 inch per second speed the radius would be 1*1/38= 0.026 in.

Obviously you need to slow down in sharp corners, but there is a limit
to that depending on chip load and burning.

Take the lowest speed you can cut without burning and the sharpest corner
you need to do. The accel required is that speed squared divided by the
radius.

Les


Leslie M.Watts
L M Watts Furniture
Tiger Georgia
(706) 212-0242

Main page:
http://www.lmwatts.com
Engineering:
http://www.lmwatts.com/shop.html
Cnc surplus for sale:
http://www.lmwatts.com/forsale.html
Carved signs:
http://www.lmwatts.com/signwp.html


-----Original Message-----
From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com]On Behalf Of Jarrett & Heidi
Johnson
Sent: Monday, November 28, 2005 12:25 AM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: Re: [CAD_CAM_EDM_DRO] Re: Acceleration rates..


Brad, my experiance is limited and bolstered by the reports of others,
however the 'spray on bond' I was refering to is a type of high build
polyester primer used in auto body shops. If need be I could get you a
product number and name as my father owns a body shop. The other
concideration is the type of foam to which it is applied. The typical blue
[ or pink] insulation styrofoam can be attacked by the polyester based
components, however my plan is to use urethane foam which is pretty much,
un-effected by any and all [ well most] solvents.

As far as the acceleration rates and what not are concerned, I'm totally in
agreement that they will have to be set by trial and error, what I'm trying
to get a grasp on at this point is just what is even the ball park. I'm
getting an better idea... however I'm sure the end result will be to just
built it as fast and robust as I can afford [ or want to spend] and then
tune it to what it will actually do once we get to that point.

Thanks
Jarrett