change CAM parameters from inches per minute to inches per second

[SDFrog]

I'm looking to change the feed rate input blocks for the CAM functions from inches/min to inches/sec. I have been doing the math manually, as my machine takes inches/sec inputs but doing this is just another step in learning this software. Anyone know how to do this? 

[michaelmoe]

Do you mean that you want to input inches per second when you are programming (see it in the CAM strategy wizards/windows) or do you mean that you just want to be able to set the inches per minute correctly when programming and have the post processor convert the feedrate to inches per second? I don't know that the former will be possible, but the latter is doable. I'll have to test it out to be sure (if that is what you are after), but for the most part you can apply math within the post processor to facilitate conversions like that. I have gone to the extent of doing math on tool numbers to generate workspace coordinate numbers. What you can do in the post processor is often limited only by how imaginitive you get with the variables available.

If it were me, I'd be looking to program in inches per minute, but get the output in inches per second. For the most part, any interaction you have with others will be on an inches per minute or mm/minute basis, so there is some disadvantage to thinking in terms of inches per second. It may take a short adjustment period, but it would probably be worth adapting. I did the same to learn to work in millimeters in CAD/CAM, but I do all of my actual shop measurements in inches. It took some time to get used to working in metric, but I find that math easier to deal with and the conversions are second nature now. Even still, old habits die hard and my use of the metric system ends in the digital world. It would be a much smaller adjustment to learn programming in in/min vs in/sec, so you should be able to get used to it quickly.

[daniel_lyall]

if you mean when setting your cut paths and selecting cutting tools you can change the tool feed in the tool library to in/sec, in/min, mm/sec, mm/min, mm/m.

what control software are you using.

[SDFrog]

I would like to input parameters as inches/sec. My control software is shopbot 3X. I have been programming my cam this way for about 2 years and do not really feel like switching. I know the math is not hard, but having to do math is a potential error point I would like to avoid, Misplaced decimal here or there. 

In the tool library I changed the feed rate (as an example) to "3.5 inches/sec" and it would not accept that. any ideas? 

[SDFrog]

the post processor I am using does the conversion for outputting, it is only a consideration when inputting the parameters during cam setup.

[daniel_lyall]

well fusion does not do in/sec 

[kb9ydn]

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@justinAVBGE wrote:
the post processor I am using does the conversion for outputting, it is only a consideration when inputting the parameters during cam setup.

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I don't think it is possible currently, but this is really a question for the CAM developers.

C|

[daniel_lyall]

well its in the wrong places then @SDFrog you need to post this in here https://camforum.autodesk.com/

I have asked for it to be moved

[SDFrog]

Thank you for your answers guys. 

[jeff.walters]

You can enter the feed as in/sec and ignore the “in/min” in the field, then have the post convert it to whatever output the machine needs (I believe it’s in/min). That way you can just put in whatever value you want. Yes it’s a work around but the post will then be doing the math instead of you.

[michaelmoe]

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@jeff.walters wrote:

You can enter the feed as in/sec and ignore the “in/min” in the field, then have the post convert it to whatever output the machine needs (I believe it’s in/min). That way you can just put in whatever value you want. Yes it’s a work around but the post will then be doing the math instead of you.

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I suppose that would be correct and really there would be no need to convert anything either. In fact, you would have to use a post processor that specifically does not change the feedrate value from in/min to in/sec or you would have a problem. If you input in/sec into the in/min dialog box and the post processor passes the value on as the feedrate without conversion, the controller would understand it as in/sec and it would operate correctly. An entry of "10" would produce "F10", which a controller that reads feedrates as in/sec would interpret as 10 in/sec, not 10in/min even though the dialog box was in/min.

The main thing you loose is the ability to simulate the motion correctly (I think the simulator would honor the in/min value and run very slowly) and the calculations for machine time would also be far from correct (60 times longer). You can slow the simulation down manually with the slider, so that's not really a big deal, and honestly the machine time calulator is always way off since it doesn't account for acceleration factors that the real world machine has to deal with anyways, so at this point you really wouldn't be loosing much functionality by doing it that way. 

[SDFrog]

Awesome information gents. Thank you. I'll test it out and see how it works. -- Kind Regards, Justin Gonzales Owner & Operator, Wudy Werks LLC Http://wudywerks.com Facebook.com/wudywerks

[daniel_lyall]

you could do up a spreed sheet to work it out for you that would be the quickest way to do it.