Loft exercise question

peter_hughes651

Hi - I'm working through the excellent self paced training and feel I'm making quick progress which is satisfying. In the loft exercise I have no problem creating the profiles and planes as directed in the exercise. I feel confident I have followed the instructions. But when I come to loft the 3 profiles together I either get an error and a strange red shape or a loft that has a some strange twists in it. If I only loft between any 2 layers the result looks as I'd expect (1st to 2nd layer, or 2nd to 3rd, or 1st to 3rd). It's only when trying to loft all three layers the problem occurs. I look forward to your insights and understanding how to complete this exercise successfully. Thank you.

robert_scott_jr_

Please post a link to your document.

peter_hughes651

Hi Robert - thanks for getting back to me. Here is the document link:
https://cad.onshape.com/documents/1b27e8dea8c1f6fd764c0b28/w/61d60dbb16b4b93527741111/e/4ad625447939dfcefc6bd6f5

peter_hughes651

Hi Robert - thanks for getting back to me. Here is the document link:
https://cad.onshape.com/documents/1b27e8dea8c1f6fd764c0b28/w/61d60dbb16b4b93527741111/e/4ad625447939dfcefc6bd6f5

robert_scott_jr_

Hey Peter. I don't have enough knowledge or experience to resolve your problem but I played around with a copy of your document to give it a shot. I seem to remember coming across a post or two with a like problem and some replying comment that the number of segments in each sketch have to have to match. So I made that happen. The loft turned out better but I don't think it's the desired result. Perhaps another member can give the proper guidance. Scotty

https://cad.onshape.com/documents/f00485cc61654f12a54ed9cc/w/b657bc5e95f01f6f41f752ac/e/4336cf46fb70e959b74acec3

wayne_sauder

@peter_hughes651
Your issue is that the plane to the top profile is supposed to be offset from the plane that the bottom profile sketch is. You have it offset off the middle. Double-check your offset distances on both offset planes as well. Good luck learning. 

peter_hughes651

Thanks Wayne - I have redrawn the exercise, noting in particular that the middle and upper planes both reference the top plane. I still get the unwanted twist in my loft. Any other thoughts?

https://cad.onshape.com/documents/1b27e8dea8c1f6fd764c0b28/w/61d60dbb16b4b93527741111/e/4ad625447939dfcefc6bd6f5

peter_hughes651

Thanks Robert - appreciate you taking a look.

wayne_sauder

@peter_hughes651
 The instructions in the learning center state that the midplane is to be offset by 50mm in the link that you provided it is still set to 25mm. 
 Be aware that this is a very basic exercise that yields a somewhat acceptable (but not in real life) loft if completed per exercise. Robert is right that there are ways to take this loft to the next level however that gets into advanced surfacing so if interested keep studying and you'll learn those in the surfacing learning modules.  

peter_hughes651

Thanks Robert and Wayne - appreciate you taking a look and providing your comments and your patience. Made the change to middle plane offset 50mm and it all works.