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Mr NCT

Site Moderator
I haven't found another answer for Fusion, maybe there's one for onshape. If you use rollation you can get it back to cad by making your rollation pattern, scanning back in and using it as a pattern in your cad program. It's a clunky procedure but for me it was quicker and more accurate than exactflat was (when it was working).
 

FlyerInStyle

Elite member
First I tried exporting from Fusion 360 to Exactflat (which is no longer working with Fusion) and that got close but not really good. It took a lot of trial fitting and trimming to get the seams close. Using rollation gets much closer and, for me, takes less time overall even though you have to make a form first that's only used to get the shape of the skins.
how do you do rollation? been trying to find a way for a while for fusion. Is there a tutorial online?
 

Mr NCT

Site Moderator
There are some youtube videos for sheet metal, the idea is the same. I make a form by putting formers that are 3/16" larger so that the outer edge is where the outer skin of the body would be. Here's one I did for the Wedell Williams I'm working on.
WW44.jpeg

Then I use card stock and roll it around the oversized formers and trace the edge of the former on the card stock. That gives you the shape of the skin. I use card stock because it is stiffer than paper and holds the shape without wrinkling or deforming.
 

FlyerInStyle

Elite member
There are some youtube videos for sheet metal, the idea is the same. I make a form by putting formers that are 3/16" larger so that the outer edge is where the outer skin of the body would be. Here's one I did for the Wedell Williams I'm working on.
View attachment 242766

Then I use card stock and roll it around the oversized formers and trace the edge of the former on the card stock. That gives you the shape of the skin. I use card stock because it is stiffer than paper and holds the shape without wrinkling or deforming.
so you basically use trial and error? no computer calculations? that seems to be the way most people do it.
 

Mr NCT

Site Moderator
so you basically use trial and error? no computer calculations? that seems to be the way most people do it.
Yup, though with a little practice you get it really close to right the first time. I'm now way closer than I ever got using exactflat. The skins on the WW44 have less than a 1/16" gap at the worst points on the first try. So trial but not so much error any more.
 

FlyerInStyle

Elite member
Yup, though with a little practice you get it really close to right the first time. I'm now way closer than I ever got using exactflat. The skins on the WW44 have less than a 1/16" gap at the worst points on the first try. So trial but not so much error any more.
how do you bring it into the virtual world?
 

Mr NCT

Site Moderator
I take the traced sheet and scan it, then import that to my cad program, scale it properly and then use it to draw over.

S1.jpg
On this one, because was large I drew a center line, matched that to center lines on the formers, taped it in place and only traced one side. As you can see in the pic I also put in a reference measurement to make scaling easy.

rollation.jpg
 

FlyerInStyle

Elite member
I take the traced sheet and scan it, then import that to my cad program, scale it properly and then use it to draw over.

View attachment 242806
On this one, because was large I drew a center line, matched that to center lines on the formers, taped it in place and only traced one side. As you can see in the pic I also put in a reference measurement to make scaling easy.

View attachment 242807
nice! Ill have to try it out some time. thanks for the tips. Have you had ones that don't fit on a scanner? How do you hold them in place while tracing them out?
 

Mr NCT

Site Moderator
nice! Ill have to try it out some time. thanks for the tips. Have you had ones that don't fit on a scanner? How do you hold them in place while tracing them out?
I’ve tried just rolling on the table but that never worked. Also tried a little spray adhesive also not ideal. Taping the center lines works the best for me.
Scanning is a bottleneck. That’s why the one in the picture is only half. (And I got a tabloid size printer/scanner)