How to estimate run times?

[ejsp]

Is there any way to estimate the machining time on a .sbp file in the Shopbot 3 program? I know that some software programs can calculate an estimate time, but the Shopbot program, since it actually runs the machine, would give the best estimation. When I tried using other programs for estimation, the times are not even close.

[Gary Campbell]

Edward..
Check out this post. YOu will have to adjust the scale and get your approximate machining time from the design/cam software. http://www.talkshopbot.com/forum/messages/20164/16985.html?1171505275
Gary

[Brady Watson]

There are several factors that can throw off estimated times. The biggest of these is VR values - and your office computer and SB computer should have the same exact VR values if you want a good estimate. Even so, the previewer can be off. What you need to do is calculate a time factor for YOUR machine & no 2 machines will have the same time factor.

Regular 2D profile cutting, pocketing and drilling should be very close to what the previewer puts out. 3D relief cutting and v-carving however often take longer in the real world than the previewer reports. I have discovered that my machine has a time factor of 1.38:1, which means that when I run a 3D file, it takes 1.38 times longer than what the previewer says, provided that my speeds are set correctly in my SBP and my ramp values are set to my preference for 3D cutting. I run the file thru the previewer & record the time. Then I run the file (cutting the part) and read what the elapsed time was in the .log file for that part file & divide by the estimated time. That's how I got the time factor for my machine.

-B