FreeCAD: A moderately complex example
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Help Support Home Model Engine Machinist Forum:
Andy, would you be prepared to share the files for the housing also- I have printed the impellor, it came out very nicely thanks, and now I would like to print the housing for it. This could be a very useful tool in the mess that passes itself off as my workshop.
Ken.
Ken.
Hi Ken,
Sure, no problem. I am releasing the FreeCAD and .stl files under the Creative Commons BY-SA 4.0 license, which basically means anyone can use or distribute freely so long as attribution is made. The .zip file is too large to attach here, but you can download it from this link: https://www.wakefieldphd.com/impeller.zip
The FreeCAD file is nearly fully parametric via the included spreadsheet. (Nearly - I'm not sure I parameterized the screw hole dimensions, but that's about all.) Because there are so many parameters, any change to any parameter will take a good bit of time for FreeCAD to recalculate the entire project. To avoid that long delay, you can right-click on the project in the FreeCAD model tab (the project, not one of the parts within the project) and select "Skip Recomputes." Then you can make as many changes as desired to the parameters before clicking on the recompute icon to do all the changes at once.
Note also that changing parameters greatly can result in confusion for FreeCAD due to the way the sketches are constrained. If you get an error after changing parameters, revert back to the original and try changing the parameter just a small amount - or go into the sketch and "untangle" whatever has gotten tangled up when parts of the sketch have moved larger distances.
I'm happy to answer any questions ...
Sure, no problem. I am releasing the FreeCAD and .stl files under the Creative Commons BY-SA 4.0 license, which basically means anyone can use or distribute freely so long as attribution is made. The .zip file is too large to attach here, but you can download it from this link: https://www.wakefieldphd.com/impeller.zip
The FreeCAD file is nearly fully parametric via the included spreadsheet. (Nearly - I'm not sure I parameterized the screw hole dimensions, but that's about all.) Because there are so many parameters, any change to any parameter will take a good bit of time for FreeCAD to recalculate the entire project. To avoid that long delay, you can right-click on the project in the FreeCAD model tab (the project, not one of the parts within the project) and select "Skip Recomputes." Then you can make as many changes as desired to the parameters before clicking on the recompute icon to do all the changes at once.
Note also that changing parameters greatly can result in confusion for FreeCAD due to the way the sketches are constrained. If you get an error after changing parameters, revert back to the original and try changing the parameter just a small amount - or go into the sketch and "untangle" whatever has gotten tangled up when parts of the sketch have moved larger distances.
I'm happy to answer any questions ...
Thanks Andy, I downloaded the files ok and the impellor housing is now happily printing on my Prusa.
I haven't made any changes yet- I'll print a complete one out first so I can see if I actually need to change anything.
But I do note your comments about changing multiple parameters- I catch myself out with this frequently in openscad- I change something and instantly press F5, then realise I am going to have to wait half an hour (or sometimes more) for it to compile before I can change the next item.
Note to self- engage brain BEFORE engaging fingers!!!
I haven't made any changes yet- I'll print a complete one out first so I can see if I actually need to change anything.
But I do note your comments about changing multiple parameters- I catch myself out with this frequently in openscad- I change something and instantly press F5, then realise I am going to have to wait half an hour (or sometimes more) for it to compile before I can change the next item.
Note to self- engage brain BEFORE engaging fingers!!!
