16. Big Mistake!
…… ‘read the instructions’ it said on the tin! This epoxy looks so easy to handle, but …. You need to read about and understand this stuff.
It seems that for just bonding two surfaces together it is pretty easy, but now try a coating over wood and it turns into another kind of beast. My studio is on top of a hill by a woodland, so a tad cold and a tad damp; two things epoxy does not like. I opted for West System epoxy, and I have been using the slower hardener 206. That is because as I am, to a greater or lesser extent, working on my own so I thought the longer ‘open’ time would be useful, wrong. The cold alone gives it a longer ‘open’ time and a shorter ‘open’ time is usually preferable.
The disaster is that a by-product of the curing process is a waxy film on the surface called ‘amine blush’, and it needs to be washed off before the boat can be re-coated. This is where the faster hardener comes in. Coat the boat with the epoxy and while it is tacky but not yet cured (and therefore has not produced the amine blush) coat is again. That way you can put several thin coats of epoxy onto the boat in one day, without having to wash down every coat.
The other important element is heat, both in the viscosity of the mixed epoxy and the room where it is to cure. So last week having spoken to a very helpful ‘Richard’ in the technical department of West System UK, I have started to sand down the entire boat but not before I have washed down the entire boat first. Having explained that he also told me that because I had already sanded part of the boat before I had washed it, that I had probably sanded the amine blush into the sanded surface aaaarrrrrr. So last week I built a box to store the epoxy in, as they outline on their website. It has a light bulb for warmth and a thermostat in it and is now a tepid 21 degrees celcius.
It set me back a few days in reality but I have already adjusted the amount of time I expect this boat to take to build. It is one of those PhD questions (don’t ever ask a PhD student when they will finish their paper, they won’t know!) so from 18 months I think the reality will be nearer 24-30 months. If anybody is reading this to glean information proir to building a boat then think carefully …. it is a HUGE amount of work. Or maybe I’m getting old!!!!
Anyway a huge thank you to my friend Malcolm who foolishly said he would come over and give me a hand. And after it he volunteered his son as well so I am much looking forward to Malcolm and James in the following week. Then we should be into covering territory with a bit of luck and a following wind!!!
Bye for now. Greybird.
