Re: How many pumps?

Posted by Ken Leffert on Jan 19, 2005

Hello, Kyle. On the 17LT that I built over a year ago, I mixed in 15-pump batches. The first 15-pump batch went on the center section, the second batch went on the bow, with a little bit left over for the stern, and the third batch finished up with some left over.

Those batch sizes worked very well for me, wouldn't do it any different on my next boat. I used the "pour it on the boat and spread it with a squeegee before it runs off into the floor" approach. A bigger bunch than that is liable to give you trouble by "kicking off" in the cup before you have a chance to get it on the boat.

Your time constraints sound a little tight to me. Can your building crew work in shifts? Maybe have the first batch pre-measured and ready to mix (or even being mixed) at the start of class, have another batch being measured and mixed while the first is being applied, and so on?

A note on mixing.....even a 15 pump batch requires a considerable amount of mixing. In the video, John recommends (working from memory here, so please forgive me if I'm wrong) 2 minutes of mixing per pump of epoxy. Now, you don't need to mix a 15-pump batch for 30 minutes, but certainly mixing for 5 to 10 minutes wouldn't be overdoing it. Might have to introduce the class to critical-path scheduling theory to get it done.

In Response to: How many pumps? by Kyle on Jan 19, 2005