Introduction: Copper Bike Fender

By Cantine Furniture

This is a sweetass copper fender for my bike. My brother made it for me with an English-wheel and a press-break. I helped a little, but mostly I was busy taking photos.

Step 1: Get Your Materials

This is actually the piece for the back fender, but we haven't made that one yet. It's just a medium gauge piece of copper, same as the front.

Step 2: Press-Break

We trimmed the front fender down to size using the break (the bottom part of this machine, the two metal plates facing you). Then A-Rod sent it through the rollers to get it nice and flat, giddyup!

Step 3: The English Wheel

This is an English wheel A-Rod made from scratch. He found the bearings on the internets and then fabricated the frame (the blue "C" shape). What can I say? He's badass, that's what. Back in the olden-days, they used English wheels for making fenders for cars and other things you wanted con-cave/vex metal shapes for. It works by spreading the metal outward, and you change the bottom bearing depending on the shape/curve you're after. Mostly it's a lost art, but I think some custom automotive and motorcycle shops might still put English wheels to work.

Some of the photos aren't that great here, but I wanted to be able to show a couple styles of bearings and these were the only pics I had.

Basically, he's creating the curvature by rolling the copper plate back and forth between the bearings.

Step 4: Preparing the Surface for Ferric Nitrate

Once we had the general shape, we trimmed the square ends using a left-cutting airplane snips, filed the edges so I wouldn't cut my legs wide open, sanded the surface to get it nice and bare, and then gave it a good cleaning to get any oils from our fingers off the surface. I'm not sure, but I think he may have used alcohol to wipe it down.

The purpose of getting the oil off was so the ferric nitrate would really get into the metal.

Step 5: Ferric Nitrate + Blowtorch = Good Times

What the hell is ferric nitrate, and why would you want to use it?

Basically, it's rust water. I wanted the copper to oxidize and get all green and badass, so this is what you do.

Clean your copper off, dump a bunch of F.N. on it, and hit it with a blow torch. I think we probably spent about 3-5 minutes on this step, mostly torch time.

You can see I drilled some holes (4) in the fender just previous to us cleaning off the surface. I was going to have to attach it somehow, and that seemed like the best way.

Anyway, it got some pretty nice flame scaling on it, and we left it in the sun for about 30 min to really let the F.N. do its work.

Step 6: Attaching It to My Bike

So, as you can see, I just ran a couple zip-ties through the holes, and strung it around the bottom tube of the bike. The tension from the curvature of the fender against the bar made it so I didn't have to have the zip-ties too tight, which is good because I didn't want to bend the copper and I wanted it to be adjustable in case it needed modification.

Once I'm sure I have it the way I want it, I'll potentially class-it-up a bit and change out the zip-ties in favor of something more befitting of such a beautiful fender. Maybe not though, we'll see.

Grazzie infinite fratello magnifico!