[SOLVED] Subtractive loft creation takes a lot of time

[steposka]

Greetings!
I am trying to model 3d printable gearpump using, obviously, Part Design workbench. I use FreeCAD for modelling my 3d prints, sometimes I face some issues like I do something one, possibly logical, way that leads to freezing and runaway in terms of memory (just gradually eats more and more RAM till I kill the process or, if I am not quick enough, restart the computer) but trying other possibly logical way is working just fine. Today I tried to make subtractive loft for the first time, creating two sketches on the both sides of the part, selecting them then clicking on subtractive loft creating button and the process of creating the loft resembled the runaway I am familiar with, rising usage of memory but it eventually decreased before I killed the process. I've it alone doing its own thing, went outside doing something on a garden and probably after tens of minutes the loft was created. However the process was taking more ram than ever, even though the program was responsive it was very laggy and every movement needed quite a lot of computational effort, way too much considering how small and relatively simple this loft element is. I remeber kinda same scenario with linear patter in which I tried to make 100 quite simple objects in a row, almost as simple as a block. It did it after a long while and the result was similarly laggy. So my question is:

• Did I something wrong way? If so, how to do it properly?

• Or is it rather because my PC is ancient old?

It is not very important feature, I mean it would make virtually no difference in the pumps' performance, but I try to learn as much as possible along the way. So thanks in advance for your time. And I hope I hit the right forum section.

EDIT: I use appimage, version 0.19 revision 24291 64-bit on Linux Mint 19.2; CPU i5 660 underclocked to 1,2GHz (usually more than enough, saves energy, less heat...), RAM 16Gb DDR3 1333MHz, GPU nVidia GeForce GT710 (GK208B) 2Gb

[chrisb]

You can increase the values for Deviation and Angular deflection.

[steposka]

You can increase the values for Deviation and Angular deflection.

Thank you for your help! That was the cause of the problem. When I was exporting files for 3d printing, holes and arcs were rough, then I decreased these values to smooth round surfaces. Since then I left these values insanely low, which was fine until now. Now it is at 5% for deviation and 10° for angular deflection. It looks fine, making the loft is matter of seconds and it is not laggy anymore. Thank you for support, even though this was kinda silly problem, and making a great piece of software!

[GeneFC]

I believe you will find that the linear deflection is much more important than the angular deflection. In most cases the default angle of 28.5 degrees will work fine. On the other hand tightening the linear deflection to less than 0.1 is often useful.

Gene

[chrisb]

If it is only for export, you can use the MeshDesign workbench to have more control over the tesselation.