Aerofoil shape and multi shape cross section to sheet metal for notching

[intentbikes]

Hi,

I'm trying to notch some tubes for a fixed gear bicycle frame with an aerofoil shape downtube and a somewhat triangular shaped cross sectional top tube. I've modelled these tubes by loft and sweep commands as these tubes have different cross sections at their ends. I'm trying to convert this into sheet metal so that I can notch the tubes without using expensive Mills and cutters. The issue with the aerofoil shape is, when I'm trying to convert it into sheet metal ( I've followed the protocols of having a small open seam) , I'm not able to select the entire body, instead only faces are getting selected

The issue with the triangular shaped cross sectional tube is, when I try to convert it into sheet metal, i get the following error: ' Can't calculate body thickness. Select the base face of a valid sheet metal body ( typically a wide, flat area' 

Any help would be deeply appreciated! Attaching the screenshot of how these tubes look like 

[jhackney1972]

You will need to attach these files to a reply post so the Forum users can take a look, pictures are hard to convert.  If you do not know how to attach your Fusion 360 model follow these easy steps. Open the model in Fusion 360, select the File menu, then Export and save as a F3D or F3Z file to your hard drive. Then use the Attachments section, of a forum post, to attach it.

[Warmingup1953]

You say different Cross-sections along the length of the tube?... Because of the geometry of your "tubes" that may well create significant issues for a sheet metal conversion. Please share your Fusion 360 file if you are able.

[Warmingup1953]

Perhaps you can use a Lofted flange (Sheetmetal) to emulate your tube close enough?

[intentbikes]

I'll be trying this. Thank you!

[intentbikes]

Thank you for your replies. 

I tried making two round tubes to convert to sheet metal. One tube was modelled by extruding and the other was modelled using sweep. I noticed that converting the extruded tube to sheet metal wasn't a problem at all, but the tube modelled using sweep gave me the errors mentioned in the original post ( both tubes were of the same dimensions) 

Please note that this file doesn't have the open seam along the length of the tube. 

Thanks in advance! 

File attached 

[Warmingup1953]

This Sketch, which I think is the challenge for you, will only end in tears for Sheet Metal....But it can probably be coerced. Your Sweep is in essence a simple extrude isn't it?

[intentbikes]

Hi,

When this aerofoil shape is being converted to sheet metal, I'm only able to select faces and not the complete body. Also this tube is a simple extrude. The other tubes are sweep. When I try to convert those to sheet metal, I'm getting an error which I'd mentioned in the original post. 

Thank you!

[Warmingup1953]

Again lots to improve on method-wise but I did get Unfold and Flat Pattern out of this tube created using your end sketches and lofted Flange. You should probably think about getting your basic Sketch skills in order first. And I say that as one who has not!...All these blue lines and poor connections will be a part of your problems going forward.

[intentbikes]

Hi!

Thanks for your reply. What's the best way to get this done? Been scratching my head over this for a while. This is the first time I'm working on non - round tubing. 

I appreciate your time.

Thanks