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Dimensional adjustment

Posted: Sat Jul 18, 2015 7:05 am
by bapro
I think this would be a great option to adjust the size of a print. If I put 0,1 in here today my holes gets to small and the outside perfect. And if I adjust it -0,1 the inner holes are geĀ“reat but outside measurment to small.

Re: Dimensional adjustment

Posted: Mon Jul 20, 2015 12:25 pm
by DarthRevan
If you need to increase the size of your model and holes, why not use the build in scale function of the model settings window? You can scale in just X and Y by unchecking the option for universal scaling. :D

Re: Dimensional adjustment

Posted: Fri Jul 31, 2015 11:54 am
by bapro
Scaling and offsetting are two different things. When scaling the size changes equal in percent but different depending on the size in mm. When offsetting its the other way around.

Re: Dimensional adjustment

Posted: Mon Aug 03, 2015 9:53 am
by JoeJ
One small note, be sure that your STL file has enough triangles to accurately model the holes. If you have a really low resolution in the STL file, the faceting will make those holes smaller than they are in real life.

Basically, a 100-sided circular hole would look more like a true circle than something like an 8-sided octagon.

Re: Dimensional adjustment

Posted: Mon Aug 03, 2015 6:22 pm
by dkightley
I'm not sure if the op fully understands the mechanism of the "Dimensional adjustment" feature. What is actually happening is that an increase of 0.1 actually stretches the shape by 10%. So, in a shape with three holes equally spaced across the direction in which the increase is made, the centre hole would have one side "stretched" in one direction and the other side "stretched"in the other direction...however the outer holes would have both sides "stretched" in the same direction, but by very slightly different amounts.

If a change is to be made to the function, exactly how should the adjustment affect the above described shape? Add a bit to each outer edge? Stretch the solid areas between the holes only? Anything other than a simple stretch raises a multitude of additional issues!!

I can only assume the feature was added to allow a simple "fudge" to a shape dimension to adjust for individual printer differences.....and not as a serious attempt to make design changes.

Re: Dimensional adjustment

Posted: Sat Aug 08, 2015 10:15 am
by bapro
It is only to analyze the G -Code. The hoizontal size compensation is an offset function. It is neither scaling or stretching.
What happens is that the material either added to or subtracted from the X / Y direction.
A detail with dimensions of 100 x 50 with a center hole of 20mm will get the dimensions 102 x 52 and 18mm hole with compensation set to 1mm.
The commonly used name for this funktion in CAD/CAM software CNC-machines is offset.
I have worked with such for over 20 years so I know what I'm talking about.

Now what I would like, if possible, is offset outward of the outer contour when entered a negative value, and vice versa.
I can see many advantages with this addon to this feature.