1 Topic by user64x

  • user64x
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  • Registered: 2013-12-27
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Topic: How to design the perfect print?

I'm not sure exactly how to explain this but I will try...

I'm trying to figure out exactly size of walls and circles during the drafting to have the perfect matching print coming out.

i.e. 0.85mm gives 2 parallel lines or +1.3mm diameter for each additional line in a circle.

But these values seemed to shift with Slic3r.

0.85mm for the first few lines will give parallel lines but get mushed after the next few.

Or

+1.3mm for each additional line only up to a certain size...

Anyone know the formula for the dimension of each line and circle that Slic3r use to calculate?

2 Reply by pirvan (edited by pirvan 2014-02-09 17:24:18)

  • pirvan
  • pirvan
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Re: How to design the perfect print?

I'm really not sure what you're trying to do, but I can tell you one thing.  You don't need to put any draft in your model.  Drafting is for injection molding, where you build a slight draft/angle in the sides of your model so it can be pulled out of the mold.  With 3D printing that is not necessary, you simply build the model with normal sides, no drafting.

The only thing you might want to account for, is the width of your extrusion. 

With certain slicers (like Kisslicer), you can account for it by selecting an inset for the print, but I don't think Slic3r has such a setting (unless someone else knows of one). 

With Slic3r we adjust the X & Y calibration to produce an object with the exact outer dimension we want, so essentially we force the printer to print a slightly undersized path.  The drawback to that is that, while your outer dimensions might be perfect, inner cuts or holes will be undersized.

To print or, 3D print, that is the question...
SD3 printer w/too many mods,  Printrbot Simple Maker Ed.,  FormLabs Form 1+
AnyCubic Photon, Shining 3D EinScan-S & Atlas 3D scanners...
...and too much time on my hands.

3 Reply by grob

  • grob
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Re: How to design the perfect print?

I think by 'drafting' user64x is referring to technical drawing (which I've found in engineering computerland is now sometimes used as an all-inclusive term for using cad software, both 3d and 2d - don't start on whether this is accurate, it just happens!)
http://en.wikipedia.org/wiki/Drafting

Nophead of mendel 90 reprap fame did a post on hole-sizing you may find interesting, user64x:
http://hydraraptor.blogspot.com/2011/02/polyholes.html

SD3. Mk2b + glass, heated enclosure, GT2 belts, direct drive y shaft, linear bearings, bowden-feed E3D v5 w/ 0.9° stepper
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