Fairing, Highbuild, Port hull

It aint over till its over

Posted by Paul

Just when you thought the worst of it was past and that you could just wave a sanding board at the hull and paint another layer of highbuild reality hits.

I started sanding before the highbuild had fully set. I didn’t realize it at the time. The sanding board would clog after just a few minutes sanding and would become almost useless. Then I realized what it was and I had a flashback to the bad bog episode. Did I mix the highbuild correctly? I mixed 8:2 (8 out of the big can, 2 out of the small can) and even though my math is not brilliant, it still equates to 4:1. I rechecked the cans, yes it says 4:1. What could I have done wrong. Then it dawned on me. It was only 14 hours since I finished applying the highbuild and the warehouse is cold. It just needed longer to set, at least that’s what I told myself so I wouldn’t worry.

sandpaper cloggedhighbuild 1st coathighbuild 1st coat bow inboardhighbuild 1st coat outboard bow

I was right, it was only the coldness that caused the slow cure. It set hard and sanded much easier after 2 days. It sets to a semi gloss finish and gives a good idea of how fair the hull is. I can see that it doesn’t need much more work. (More so when you see the hull sanded again).

Here and there the pigment or paint within the resin seemed to sag inside the resin, so in other words the resin set smooth but clear here and there with the white parts fallen somehow. I thought at first it was because the resin coat was still tacky when I applied the highbuild. It doesn’t seem to matter much. It sands back fine. It will be interesting to see if it happens again on the next coat, if so my theory about the tacky wet resin is shot.

highbuild 1st coat outboard sternhighbuild close uphighbuild after sanding 2highbuild after sanding 1

The highbuild is easier to sand. The finish from the coarse roller I used is like orange peel with highs and lows within it so that at first you are only sanding the high part down to the lows and is, as a result easier and faster to sand. Here and there the whole layer of highbuild is sanded away (high spots) and also here and there the highbuild isn’t touched by the sanding board (low spot) and will get another coat to build it up. But for the most part I sanded until the orange peel effect was sanded smooth. For the next coat I will use a foam roller which should give a smoother finish.

It took me about 4 hours to sand about half the hull so tomorrow I will finish sanding and maybe even get the next coat of highbuild on. It looks like 2 coats may be enough to finish, 3 at most. In some places like close to the main chine the highbuild is completely sanded away. This will diminish as the highbuild on the low points (areas hardly sanded) raises with the next coat to the height of the sanded back sections until I end up with the final flat fair finish (try saying that with a mouth full of marbles!).

I sanded back with 80 grit for most of the hull, but used some 60 below the waterline to cut through a bit faster. The finish from the 80 grit feels very smooth compared to the 40 grit finish on the bog. So smooth in fact I think it is smoother than a babies bum, but lacking a baby nearby to compare I only had a babe, Jo, but she refused to let me compare and one can only surmise as to why. Does she fear that the hull may in fact be smoother? I guess we will never know for sure.

I will use 120grit on the next coat which I hope to get done on the weekend. Even though it is easier than sanding bog it is still hard work and I cant wait until it is done.
Finally, I can’t finish this report without thanking all the well wishers that emailed to congratulate us on the wedding. We really appreciate your emails and best wishes.

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