Quote:
Originally Posted by Spark
If you use thin sheet alum it can sometimes be better to weld. Though usable, rivets and bolts could rip out or bend the metal. A long weld, not just a spot weld, has more surface area connecting the two pieces. However, if you need precise pieces it's easier to rivet or bolt. I'm not saying keeping welded pieces flat is impossible, just harder.
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Hi Spark,
Going to pretend I'm Weld Man here for a second...but if you're talking about bending the metal, a continuous weld is always going to produce more warping in a part than riveting if all else is equal.
Mainly what happens is you heat up the metal and it gets softer (more malleable, and a bunch of other science jargon). So what happens is it'll distort and actually pull to a side. Afterwards there will be additional stresses inside the material (as with all fastening systems, that's how they work) that keep the material bent out of place.
Even if you preset your material and had it exactly in place, a long continuous weld is 100% going to distort a thin sheet of aluminum. Fortunately, rivets have your back and could be used to hold the sheet in place to help reduce warping.
Here's a link that has some good tips on how to mitigate these warps.
http://weldingdesign.com/archive/avo...ion-thin-sheet
Main points from this link are things like, backward walking, non-continuous/stitch welding, and presetting.
It's true that rivets can bend a thin piece of aluminum, but that would mean you have other issues in your setup. If your pieces aren't mated correctly (air gaps, bends aren't proper) when you're about to rivet then yes, rivets will bend your rig...they're trying to pull the pieces together after all! And if we're talking about the retaining mandrel or the head impinging on the surface of the metal...chances are you're using too much force on too soft a material, that ones on you and not the rivet!
Rivets are only as good as the person/design that's using them, and they're definitely not the bad guy!
Best Regards,
RM