Carbon Puncture

Triathlon Forum
1

Damn, just got around to inspecting my disc after getting back from Nationals. Found this … any recommendations on how to repair it?

http://multisport.battles.cc/Photos/puncture.JPG

I would assume I just get some epoxy and spread it/sand it lightly and polish?

Doesn’t seem like the integrity would be compromised… so perhaps just some CF tape?

2

You don’t think it damaged the structural integrity?

3

No, not enough to cause a failure. do you?

4

I don’t know. Can’t tell from a photo. But any crack or fracture in a carbon product and I’d be concerned of the structural integrity of the item. There’s simply no way the wheel hasn’t been fatigued in some fashion due to the puncture. Can you repair it and minimize further damage, cracking, down the road. Maybe. But the damage that has already been done IMO is irrepairable. It’s a back wheel so that better than it being a front wheel when you’re looking at a wheel failing.

5

Just sell it on EBAY and claim it to be “brand new in excellent condition with 50 miles on it.”…sorry I just bitter about being ripped off.
Doesnt look to be structurally compromised in anyway…clear nail polish and some epoxy will take care of cosmetics.

6

I think it’s ok. The puncture is ~3/4 inch.

I realize the the strength in CF is from the fiber and obviously that has been compromise, but I don’t believe enough to cause a failure. If it were a regular rim then yes, but a disc no.

I contacted my Motorcycle shop… I described it to them and they are going to look at it. I know they deal with this stuff on a regular basis and with far greater stress concerns.

7

I would not think you lost any structural integrity from that ding. I would repair only to reseal it from moisture.

Looks like an interesting whack. Any idea how it happened? What disc is that?

8

Call the manufacturer, they either fix it or have a crash replacement.

9

Zipp - it looks like a Zipp - has an excellent repair policy. I’d contact them. I think you’d be surprised at how cheaply they could do a proper carbon patch on it.

If you want to do it yourself:

  • Sand the surrounding area about 1cm around the hole.
  • Clean with acetone
  • Buy a small sheet of 3k carbon twill.
  • Buy some WestSystem epoxy.
  • Dab the epoxy lightly on the sanded area
  • Lay down the carbon cloth
  • Dab epoxy on the cloth until it is soaked through with epoxy, but no more (imagine wetting a paper towel and then wringing all the water out of it - that is how much epoxy you want on the carbon cloth)
  • If you want to be fancy, you can then put a piece of peel-ply over and smooth it down to help soak up the extra epoxy.
  • Let cure overnight
  • Sand the edges smooth
10

It’s an old zipp disc. Early 2000 circa. No longer under warranty, it’s second hand.

Not sure, when I was at national I heard something whack the hell out of it. I got all caught up in everything though I didn’t check it before I packed it back up though. So could have been from travel, but I am a pretty careful packer. Think it happened out on the course.

11

Appreciate it.

I got some carbon cloth (Hercules AS4 ) from my motorcycle shop. They told me the exact same thing as you mentioned and even recommended the same epoxy.

A west systems 105 resin and 205 hardener.

They didn’t seem all concerned about the integrity of the disc, but were more concerned regarding the rotational stability after the patching. They also mentioned to use “as little as possible”. I told them I rarely get the bike over 175MPH, but will certainly be cautious of it.

12

put a sticker on it:) my disk was passed down to me from a sponsor and it has a couple of little dings like that in it for people who borrowed it before me. Doesn’t seem to affect a thing.