im glad to see 1501 is known when it comes to riveting
our team has used over 10,000 rivets on our robots so far, almost 2000 in some robots. They are made out of a monocoque design, which is what aircraft use. solely sheetmetal and rivets, providing a strong structure. i think youll enjoy some photos of our bots.
all we use are hand rivet guns and a pneumatic rivet gun (used rarely)… i have spent all nighters riveting the bots together. but it creates an amazing end product. if you would like more info, pm me and i can get it to you. and yes we do make errors, but you can just use the same drill bit you used to make the original whole and drill the rivet back out. almost as if it were never there.
and klekos are a neccessity when building with this many rivets :rolleyes:
those are called Clekos, they serve as a quick insert stand in for a rivet to get things aligned.
Think of them as vice grips for sheet metal joints, they hold everything in line when you start putting in the real rivets.
While I still use bolts for super high shear areas, 90 percent of the fasteners we used last year were rivets. Our entire robot was essentially 1/4" aluminum rivets, 1x1x1/16 aluminum tubing, and 4"x4" aluminum triangles for corner connections. We never had a rivet fail. Removal is easy as pie too, just drill through. Hole enlargement was minimal in my experience since the center of the rivet kept the bit straight.
I think someone said earlier that a team could dissassemble and reassemble a robot faster using rivets than bolts. I have to agree, you just have to drill through and re-rivet. I also hate having to tighten loose nuts so riveting is definitely my favorite.
-Vivek
EDIT: With a good square, you can get perfect 90 degree angles without machined corner braces. We just cut them on a miter saw and clamped everything down to a work bench and lined it up with a square. Make sure your holes are aligned though.
EDIT2: We probably saved a few pounds by using rivets too. They are SOO much easier to maintain. Sorry about the edits, I just really love rivets.
they can be purchased from an aircraft supply store, if you want i could post the link (i would have to look it up quickly)
Basically, to drill all the holes we use templates. we drill one hole, put the drill template on top (the templates are just like ruler with holes drilled various distances from each other, commonly use 3/4-1 inch spacing) we kleko it in (kleko=temporary rivet) and then we drill the opposite side hole in the template, kleko that in, and then drill in between.
short quick description: a kleko is a temporary rivet that is inserted with a plier like specialty tool. it holds things together so that you can align before you actually put rivets in.
(you want to space klekos approximately 3-4 holes apart on straight lines, or about every other hole on complex parts like the curve in the picture mentioned) 50 klekos will do most teams well, i believe we have about 200 or so:D
For clarity, you should already have seen what a klecko is (see some previous posts). A **bucking bar **is a relatively heavy bar of metal, maybe the size of a hammer head, with a dimple in one end made to fit the head of a solid rivet. You hold the rivet (which looks like a short nail with no point) in place with it, and whack the other end with the pneumatic hammer. The inertia of the bar holds the rivet in place so the hammer can flatten the other end. They also make bucking bars for the end-to-be-flattened, one uses it kind of like a chisel with a manual hammer. A little more effort, but really low-tech and thus simple. But you need three hands: bucking bar, flattening bar, and hammer.
Very large rivets (think George Washington Bridge) are heated so they flatten more easily, with the important added benefit of shrinking when the cool, thus pulling the joint together even tighter. Small rivets (think FRC177 robot) rarely are heated.
