Kerf bending tips for laser/plasma cutting

[Dan Dubeau]

Just stumbled on this video explaining some tips and tricks for kerf bending laser cut sheet metal parts. A bit of a drawn out video, but I learned some things I did not know that will certainly come in handy. The one take away is the angled web, and to keep both the kerf, and web the same thickness as the material. You can go thicker on the web if you want more strength, but obviously gets tougher to bend by hand as thickness goes up. The only times I've ever used this, I always welded the seam anyway, so ease of bend was always my greatest concern. I also just more or less guess on the kerf size and placement. I've never angled my kerf like that, and the reasons why they do it, make sense to me, so I'll incorporate that into any future projects requiring it that I send out for laser cutting. For stuff hand cut with the plasma at home, I'll probably just keep doing things the same way I've always done them though, as cutting the angles by hand would be tough lol.

 

[Stuart Samuel]

That was interesting, thanks Dan.

At work we do church lighting bodies out of aluminum sheet (~1/16”) with straight dashes. Lets us store them flat until needed, and they’re bent up into a hex. The ‘twist vs stretch’ idea is interesting, but I feel like I can still see a bit of a stress riser happening here:


Not that I have any really clever solution to that, mind you. Maybe a radius at the end of the slot/smile/wave?

 

[Dan Dubeau]

I bet a radius if you could fit it would help. They always help. The one standout for me for using the wave method was how it affected the bend line and put more material out at the edges of the corners. I couldn't help be curious looking at some of those closeups wondering how an autogenous weld run right down the corner would look. I was hoping they'd run a weld down one to show us. Makes me really want to try it, but I don't currently have any project ideas that need anything laser cut.

 

[Stuart Samuel]

I bet a radius if you could fit it would help. They always help. The one standout for me for using the wave method was how it affected the bend line and put more material out at the edges of the corners. I couldn't help be curious looking at some of those closeups wondering how an autogenous weld run right down the corner would look. I was hoping they'd run a weld down one to show us. Makes me really want to try it, but I don't currently have any project ideas that need anything laser cut.

Yep, I had the same thought about running a torch down that to fuse it.

Hmm. Maybe I'll talk to our engineer when I'm back at work Monday, and ask him if he could CAD this up, and slip it into some paying laser cutting in the next few months, to try it out. (I'd like to do the same with some flexures for mounting plates, actually, I feel like it would save a lot of needless precision hole placement that nobody's really impressed by or interested in paying for)

 

[Dan Dubeau]

Hmm, flexures for mounting plates. Now that's a interesting idea!

Keep us posted if you do sneak some in to try. I'm very interested in seeing how they'd turn out.