First attempt at a part for my bike

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#1

Any tips that could help me out for future parts?

This is my first attempt doing anything like this and I was trying to keep it as cheap as I could. This was mostly just a test to see if I could make a functional part and if I liked doing it.

It’s not pretty but it’s holding up so far. I’ve put about 30 miles of hard trail riding on it now. I’m thinking of making the rest of the frame or maybe redoing the seat stay.

I did the first layer of CF with the ghetto method of wrapping it in electrical tape to squeeze the excess epoxy out. I didn’t really like how it worked so I borrowed a vacuum pump from work and found a local place to get bagging materials. I put the other layers (6 total) on in two separate vacuum bagging sessions.

I had a ton of trouble warping the CF around the part. The weave would get all screwed up and strands would stick to my gloves. It was a pretty big mess.

I was thinking for future parts it would be easier to make my foam plug and then do a mold from that. That way I could just vacuum bag a bunch of layers at once. Then I’d have two halves which I could join together and put a layer or two over the seam.

Here’s some pictures:

Cutting out the foam core. Then a ton of sanding to get it to fit right.

Fitting it on the bike

First layer of CF. I had to cut out the block on the top that attaches to the suspension link because it came out uneven.

All Done!

#2

Did you leave the foam in or disolve it loogs good

#3

No guts no glory!!!

What do you wanna attempt next?

#4

Exactly!

Welcome to the forum JDD. I can’t say how nice it is to see someone just jump in feet first. :smiley:

If you paint the epoxy on the foam first then let it tack up you will have ALOT easier time getting the dry fabric to stick in place.
And one tip if your gloves get nasty. Put more then one on each hand at a time. I wear two pairs. That way if the first layer rips, my skin doesn’t touch anything and 2nd I can just pull the nasty glove right off and have another ready to go.

#5

Good idea with the gloves! I used some 3m spray adhesive on the foam for the 1st layer. I think that first layer turned out great. The problem came when I tried to do more than one layer at a time. One layer of wetted wouldn’t stick to the previous wetted layer. I just gave up and threw it in the vacuum bag. Maybe I should have just put it all on dry and hope that the vacuum would squeeze the epoxy all the way through the dry layers?

#6

I left it in. It didn’t add a lot of weight and may have added to the overall strength of the part. And I forgot about the weight: Original aluminum part- 310g, New CF part- 120g

#7

I’m thinking of finishing the whole bike frame in carbon fiber now. I also picked up a bunch of bamboo to try and make a bamboo/cf frame.

#8

Wowzers!!!

#9

YOU ARE THE MAN JDD. jdd thinks to himself…im gonna make a part for my bike. two hours later hes bolting it on. LOL. ive been at this for a month, and all i have to show for it is a stack of bills:confused:. keep going bro…do you want to make me some rain hats for my carburetors?:smiley:

#10

I’ll make them for you!!