My problem is that when I add a draft angle and extrude a sketch using "offset from surface" the draft starts at the sketch instead of the surface. If the surface is curved then the projection is not the correct size or in proportion at its base due to the draft angles. Is it possible for the draft to start at the base of the projection and not the sketch. This is my first post. Sorry if this is answered already. Thanks for any help.
Hi Bian that's an interesting question and delimma. I've yet to run into too many people who use offset from surface when extruding other than myself and you. Or at least those who'll admit to it. I would like to know the answer to this question as well. That is an oddity though. Thanks, Daniel
Look to the right in the section "More Like This" or have you tried to do a search?
Welcome to SW forums Brian
I doubt if it is doable. But can you create the sketch on the surface (which you're selecting for offset) and then use direction 2 for extruding on other side.
Brian,
This is not possible. The issue is that you cannot add draft from a non-planar surface and maintain a constant initial diameter. It is a topological impossibility. You have to tweak the original sketch to make it "close enough", and then it is give & take between the sketched diameter, and the final dimensions.
Brian,
Does it help if you extrude without the draft and then add the draft as a separate feature?
Jerry Steiger
...or create a new plane at your start position and extrude from there???
Thanks for the feedback, but I'm still stuck. I will try to attach a few screen shots. I suspect that for a more experienced user this would be easy.
Are you getting any error with that??
No errors. The bottom of the cut is to narrow.
Can you post the part to understand the geometry better. Also did you tried using sweep cut.
Brian,
I'm still not sure about exactly what you are trying to do, but I think you need to extrude your feature without the draft, then use a Parting Line Draft, picking the edges on your curved face and the plane or face from the sketch for the direction.
Jerry Steiger
Adding parting line draft was the answer. I have only been using Solid Works for a few months with no formal training, and I was not aware of this feature. My next option was the sweep, but I like this much better. The sweep path curved in two nonlinear directions and required guided curves on all four corners. It would have worked, but this is much easier. Thank you every one for the help!
Sounds like you solved the SolidWorks issue (you're welcome) and have move on to a genuine geometry issue. About all you can do is reduce draft until you get the thickness you need.
One approach is to make a temporary sketch that constrains the width you need where you need it and draft out from there, and see where that ends up.
Judging from your pictures, I would say you need to apply your draft differently, probably from the bottom edge of the feature.
Brian,
I'm still not sure about exactly what you are trying to do, but I think you need to extrude your feature without the draft, then use a Parting Line Draft, picking the edges on your curved face and the plane or face from the sketch for the direction.
Jerry Steiger