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aaasigncom
11-03-2009, 04:49 PM
HOW DO YOU MEASURE YOUR TRUE TRANSIT SPEED ? DO YOU MEASURE THE TIME IT TAKES TO TRAVEL 8'?

rb99
11-03-2009, 05:47 PM
Some software will tell you the length of the vectors or toolpaths.

SB will tell you how long it took to cut the file.

Just one way.

RIB

Gary Campbell
11-03-2009, 06:30 PM
Tony...
if you want to time it for yourself:

JH
J2,90,43.589

Time the move, it's exactly 100 inches. Dont forget you will ramp up and down, so your overall (averaged)speed will be less than the max speed, but should be close.
Gary

dana_swift
11-03-2009, 09:03 PM
Hmm.. how about put two strips of aluminum foil across the path of the router bit, as the router cuts the first one then the second one a known distance later. The first foil could be far enough away from the router starting point to let the motion be at full speed.

Hook the two foil strips to two pull up resistors, catch the action on a double trace digital oscilloscope. That should get you very good accuracy if its that important.

Every time I cut a file the time to complete varies. I presumed that is due to the CPU being busy with non-shopbot tasks, but who knows? It may not be traveling at exactly the same speed each time.

Probably not a useful answer, but certainly one that will give an accurate result.

Good luck.. let us know what you learn and how!

D

Gary Campbell
11-03-2009, 09:17 PM
And that my friend, is the difference between empirical and theoretical!

Gary

navigator7
11-03-2009, 09:24 PM
I got a question.
Speaking of tin foil reminded me of continuity which made me think of zeroing the Shopbot Z to the material which means the zeroing function is a continuity test?
When you zero Z with the tool...does the tool have thickness?
If so, then the machine knows to add the thickness of the zeroing tool to the depth of cut. Am I correct?

shoeshine
11-03-2009, 09:55 PM
yup, I actually found I needed to adjust the factory settings as my Zzero plate was just a bit thinner that the values that shipped with the software. It made a world of difference in doing fine Vcarving. As you are setting up take a mic to the Zzero plate just to make sure.

dlcw
11-03-2009, 10:12 PM
Another thing to remember, if you have a vacuum hold down system, do all Z zeroing with the vacuum on. It will effect material position on top of the table and spoil board position.

Don
www.diamondlakewoodworks.com (http://www.diamondlakewoodworks.com)