Thursday, November 04, 2010

Carbon Canoe Paddle continues

A long time ago I started building a carbon fiber canoe paddle. Not from scratch but a copy of a ZRE carbon paddle. I bought some carbon fiber and some tooling resin from ebay and started with the handle. I made a mold and then a very nice part that broke the mold but came out great. Then I got distracted and put away the project for a while.

Yesterday I started it back up with the paddle blade mold. I laid up the first half of the blade mold using a technique I guess I'll call "moldless mold making". I saw this method, or at least a version of it online. Moldless vacuum bagging where some guys are making a bicycle frame and bagging the parts by suspending them in a frame with bag on either side.

I suspended the paddle in a picture frame which took a couple of tries to get right but with the plastic stretched tight when the vacuum was pulled it stayed wrinkle free and gave a nice smooth surface. The advantage of this method and why I tried so hard to make it work was that I didn't have to mess with making a mold platform or coat the paddle with mold release. After curing, you just peel all the plastic off and presto done! Sure the plastic has some thickness but who cares, I'm not worried about a tenth of a millimeter.

Unfortunately, I didn't have any peel ply or bleeder cloth so I substituted some thin white fabric which soaked up epoxy and clogged my vacuum tube. It was ok, it still worked but I had to leave the pump running and lost about 6 inches of tubing. I also experimented with warming the layup using a blow dryer which gave me an excuse to monitor the temperature with a new toy that I bought myself.