Units for feedrate

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danielfalck
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Units for feedrate

Postby danielfalck » Sun Feb 05, 2017 11:08 pm

I still use imperial units for CAM and would like to bring something up about feedrates- in the property panels it seems that there is only 'mm/s' for feedrates for Path operations.

I submitted a bug report on Mantis about this:

[bug]https://www.freecadweb.org/tracker/view.php?id=2890[/bug]

In the past, I think we ignored the units in the feedrates entries in the property panels for operations, but we really should figure out how to fix it. I know it's probably deep in the units source somewhere in the main FreeCAD App directory, but I did a little grepping and can't seem to find where 'mm/s' is coming from.
mlampert
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Re: Units for feedrate

Postby mlampert » Sun Feb 05, 2017 11:17 pm

I think the feed rate is just a number and whatever unit the post processor sets is what is being used.
danielfalck
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Re: Units for feedrate

Postby danielfalck » Mon Feb 06, 2017 12:01 am

mlampert wrote:I think the feed rate is just a number and whatever unit the post processor sets is what is being used.


That is true, so maybe the solution is to remove "App::PropertySpeed" from the property panel entry boxes and use "App::PropertyFloat" instead.
mlampert
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Re: Units for feedrate

Postby mlampert » Mon Feb 06, 2017 12:13 am

danielfalck wrote:That is true, so maybe the solution is to remove "App::PropertySpeed" from the property panel entry boxes and use "App::PropertyFloat" instead.

Gotcha' - good point.
mlampert
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Re: Units for feedrate

Postby mlampert » Mon Feb 06, 2017 12:17 am

I updated the bug.
Just for my clarification, do you have the global unit options in FC set to metric or are those also in imperial?
danielfalck
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Re: Units for feedrate

Postby danielfalck » Mon Feb 06, 2017 12:25 am

mlampert wrote:I updated the bug.
Just for my clarification, do you have the global unit options in FC set to metric or are those also in imperial?

I have set my global prefs to imperial.
mlampert
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Re: Units for feedrate

Postby mlampert » Mon Feb 06, 2017 12:42 am

Interesting, sounds like a bug in InputField. Maybe an oversight of not handling speed according to the global unit and just assuming the default.
danielfalck
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Re: Units for feedrate

Postby danielfalck » Mon Feb 06, 2017 12:46 am

I can eradicate all instances of "App::PropertySpeed" if no one objects :)
chrisb
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Re: Units for feedrate

Postby chrisb » Mon Feb 06, 2017 12:55 am

danielfalck wrote:I can eradicate all instances of "App::PropertySpeed" if no one objects :)
I don't understand the consequences, so how could I object? If it is without units I don't see any problem. If it uses units, can we assure they are conforming to the settings in the post processor? Or is it the other way round: the post processor has to be configured so that it matches the units used in the path?
danielfalck
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Re: Units for feedrate

Postby danielfalck » Mon Feb 06, 2017 1:01 am

chrisb wrote:
danielfalck wrote:I can eradicate all instances of "App::PropertySpeed" if no one objects :)
I don't understand the consequences, so how could I object? If it is without units I don't see any problem. If it uses units, can we assure they are conforming to the settings in the post processor? Or is it the other way round: the post processor has to be configured so that it matches the units used in the path?


The only indicator that there are units involved is in the property panel that has 'mm/s' attached to the entry box for the feed rate. I found that I was having to multiply my desired feed rates by 25.4 to get them to come out to the proper output with my centroid post processor. I had created a function to filter/convert feed units in that post.