Welcome to the Onshape forum! Ask questions and join in the discussions about everything Onshape.
First time visiting? Here are some places to start:- Looking for a certain topic? Check out the categories filter or use Search (upper right).
- Need support? Ask a question to our Community Support category.
- Please submit support tickets for bugs but you can request improvements in the Product Feedback category.
- Be respectful, on topic and if you see a problem, Flag it.
If you would like to contact our Community Manager personally, feel free to send a private message or an email.
Combining fillet and chamfer to facilitate 3D printing of part
no_thanks454
Member Posts: 5 ✭
I have reverse-engineered a part that I'd like to 3D print. To make it look somewhat like the original, I want to have a fairly large (10mm radius) fillet on the edges of the bottom. The bottom will also be on the print bed. However, most FDM 3D printers cannot handle overhangs of more than 70 to 80 degrees. Therefore, I would like the bottom part of the fillet to be a 70 degree chamfer, until the angle of the fillet becomes less than 70 degrees and it can continue as a fillet.
I managed to get this partially working, but only with a tiny chamfer and tiny fillet:
How can I do this in a nice way with the large fillet? Thanks!
Answers
not sure what exactly you aren’t able to do but you can apply a fillet to a chamfer edge if that’s what your after
He doesn't want the fillet to end tangent with the base face (printbed). Instead he wants a small chamfer-like face to extent tangentially from the fillet at say 70° or whatever overhang angle his printer can do.
The issue is the main corner radius of 3mm. You need to make it much bigger if you want a larger chamfer and/or fillet to be able to wrap around it.
Precisely! In the part I linked, I have done precisely as suggested above, namely first created a 70-degree chamfer and then applied the fillet to the top edge of that. This works in the sense that I could now print it. But I would like to have a nice big round-over (like a 10 mm radius big) and the chamfer doesn't generate if I make it bigger than 1mm:
So I guess my question is: how can I make this chamfer (arbitrarily) large(r) so I can whack on a 10mm fillet on the top edge 😊
A few other things…
You can change the units to mm instead of m. It will be much easier on your eyes and brain when inputting numbers.
The first sketch is WAY too complicated. At minimum, all the radii and dogbone corners should have been added separately. A basic outer shape, with a later shell, would have probably been the better way of approaching this shape.
Your rounds are set to conic. IDK if you intended that, but usually that's not needed unless you are designing an iPhone corner.
Thanks for the tip of changing the units! I already got used to just typing "mm" behind everything I put in :D
How could I do the dogbone corners assuming a shelled cube? I thought maybe face blend might work but I can't quickly find an appropriate combination of settings.
I didn't know how to combine shell with the off-square angle on the right of the part. I also printed 12 versions of the 'outline' (essentially just the outer shell without the bottom or inner features like the ribs) in order to get the fit around the sheet metal of the knitting machine right.
The bends on the sheet metal also made me pick the small outer corner radius, I can't have too much material there, otherwise the slide will interfere. One idea that just occurred to me is to thicken the bottom a bunch, create a normal point plane (so perpendicular to the profile), draw the outline of my desired chamfer+fillet and extrude-remove that.
You mean like this? Order of operations matter.