Talk Composites - The Forum for Advanced Composites

Carbon oar shaft repair

http://www.talkcomposites.com/Topic31039.aspx

By swiftarf - 11/19/2018 9:19:40 AM

Hi,
We've acquired a second-hand carbon shafted oar which has been cracked by the over-enthusiastic insertion of a handle. The shaft is 61mm in diameter, the walls are 3mm thick and the crack is 80mm long, running in from the end of the oar. We want to attempt a repair but wanted a bit of advice. The manufacturers website suggest (PDF attached) using pre-preg and heat-shrink tape with a hot air gun, but I see that you have a fishing rod repair kit available.
What would be more suitable- the XPREG XC 130 (which looks like the prepreg on the concept 2 repair pdf) or the fishing rod repair kit?
Strength is more important than cosmetics!
thanks,
Simon
By Fasta - 11/20/2018 7:47:15 AM

 
swiftarf - 11/20/2018 7:41:15 AM
No, we don't have an oven but we were going to use the non-autoclave pre-preg and a heat gun

I have done plenty of tube repairs like this, regular wet resin systems with carbon, shrink tape and heat gun.
Make sure the shrink tape is overlapped 2/3 to create 3 layer shrink film. If it is just 1/2 overlapped as 2 layers then the shrink tape can create a bit more bumpy finish. 3 layers is smoother.
By swiftarf - 11/20/2018 8:03:17 AM

 
Fasta - 11/20/2018 7:58:20 AM
 
swiftarf - 11/20/2018 7:49:55 AM
 
Fasta - 11/20/2018 7:47:15 AM
 
swiftarf - 11/20/2018 7:41:15 AM
No, we don't have an oven but we were going to use the non-autoclave pre-preg and a heat gun

I have done plenty of tube repairs like this, regular wet resin systems with carbon, shrink tape and heat gun.
Make sure the shrink tape is overlapped 2/3 to create 3 layer shrink film. If it is just 1/2 overlapped then the shrink tape can create a bit more bumpy finish. 3 layers is smoother.

Thanks for the advice. Do you think a wet system is better and how long lasting have your repairs been?

I am assuming this non-autoclave pre preg is a wet preg. Wet preg is really just a wet resin system. You may as well wet out yourself. You can do it on the job or pre wet on a board and then wrap onto your tube.

Don't be confused with (out of autoclave) this just means the material is meant for use with a regular oven and vacuum only process. It still needs cooking at 80-100C for many hours. A heat gun will not work.

It was the out of autoclave stuff I was looking at- thanks for clearing that up!
Cheers