Timing butterfly pattern

[johntwo]

I am new to shopbot and i try machining a butterfly in preview mode and it should the machining time to ove one hour. Is that the normal time or is their a setting between the computer and shopbot program i am missing?

[jamesgilliam]

John, Hard to tell from the information you have given. What size is the butterfly and what speed are you running for feed? The amount of detail also has to be factored into time. I have cut several files, one a six foot Statue of Liberty, with inside lines for painting and detail purposes that took almost two hours.

[johntwo]

Hey James the size was 3.5 inches by 3.5 inches with allot of inside detail, the speed was set for 1.5 inches per second, and router set at 16000. I did the actual cut last night and it lasted under 15 minutes which i would consider good. Do you know if there is a reason the shopbot preview estimate was over one hour?

[jamesgilliam]

John, I don't have an idea of why it would show that much of a time difference to what it actually cut at. May be time to ask support for an idea of why the difference.

[dalesouthmayd]

John,
Would you mind posting a picture of your butterly or a diagram? Inquiring minds are curious....

dale

[ted]

Hi John,

We haven't looked at the calibration of the preview cutting time estimator for awhile, and will make a point of checking it out. I'm guessing that in a small intricate file there is a lot of acceleration ramping and perhaps the time for it is being overestimated. Thanks for the input.

[ckurak]

Ted,

While you are looking at the preview cutting time, please take a look at the metric timing. For example, one of my SBP files that I cut recently was estimated by the Previewer to take 10:22:55. The actual cut time was 22:18.

This looks like this may be a factor of 25.4mm to the inch.

Thanks!

[K Simmerer (Unregistered Guest)]

I have found the preview time estimate to be very accurate. The only time I have run into a situation like this was when vectors had been nested on top of each other and a 1hour machine time showed as 2 hours. This is very difficult to detect in preview on a complicated, long machine time project. Go back to the vector and ungroup and break apart all objects until you no longer have the option. Then grab a vector and move it aside, you will probably see a duplicate vector hiding underneath it. Move that one, you may find another and so on. What would happen is the machine is tracing over the same tool path again and again, doesn't show in preview mode because it's retracing it's steps, unless you can spot the jog line from end point back to the start point, or with version 3 simulate cut in preview and watch the preview execute the entire cut.

Ahhh... nested vectors, brings back memories...
Well, no time for reliving the past.
Keith