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Taping the Sheer... or.. make every move count and don't stop till it's hard..

 Nothing flash for technique here.. just drew lines at 40mm to help me keep the curve steady...
   And your basic and sundry implements of destruction... as Arlo would say.
   This is the radius I got. The gap between the sheer panel and deck is no big thing. Thats what bogg is for... Needless to say the taping had to be done late in the day. The Duflex skin is porous but a naked balsa edge is even more so. Putting resin on a surface like this without considering outgassing is just plain stupid and will guarantee a disisater down the road. One good thing about using peel ply is outgassing is identifiable as it happens. You can see the air under it. But taping without peel ply may result in holes in the tape from escaping gas that you won't see until later and then easily dismissed as just bubbles in the bogg.
    I also decided to change the sheer line aft. I wanted more headroom in the aft cabins but just didn't catch it soon enough but this I could. Aesthetically it was wrong. Here I am in the process of trimming and standing back to have a look. This is a very hard thing to judge except at a distance.
  The red line indicates where the panels was before trimming. I believe lowering the sheer there has given the boat a longer, lower and to me, more pleasing look to the eye. In this photo you can see a layer of 20mm foam placed on top of the sheer panel in preparation for taping. Another layer of 20mm foam was placed under that inside to thicken the edge to 40mm. Also a solid piece of foam was later added at the very end to carry the line right to the transom to please my eye and provide for a barrier between marina berth and structure.
   This shows the foam used aft shaped to the balsa sheer panel and ready for taping.
   I've mixed 600 grams of resin to make bogg about half Q-cell and Half Cab-o-sil. I go over the length first and really push it into any orifice or screw hole, whatever. Fast and sloppy. Get it stuck and out of the container as fast as you can.
   Here I've worked from the stern to bow and now working backward using my palm to smooth the bogg, scooping up more as I need it to cover the raw edge. I do this to help fair and to help the tape stick in place better.
   Then back the length with a spatula to clean off bogg on the flat surfaces...
   As tidy as you can but always go fast fast fast.....
   Skim away excess
   Both sides, top and bottom..
   That part done...
   Now my secret tool.. a piece of rubber about 3 mm thick and 50mm wide
   Start at the bow and drag along.....
   The whole length, nice and steady and smooth.. don't stop and watch for the ladders holding up the scaffolding!
   And thats what it looks like at the end.
   The result as viewed from the bow.
   1400 grams resin.. go like crazy!!
   Go go go...
   Carry the flaked, wetted tape up and start laying it out.
   Once out go back and straighten if needed and make sure it is strechted taunt.
   Use the palm to push and straighten along the centre first.
   Then come back and start rolling and pulling in opposite directions. I do this BOTH sides, up and down and make sure every millimetre gets rolled but fast fast fast.... don't panic but don't waste a move either.
   Peel ply
   pull snug for the entire length..
   In place and ready to work.
   Same thing as in rolling the tape, pull in opposite directions, first one side then the other...
   A little more resin to help wet it in as the peel ply should become transparent.
   pull with one hand whilst rolling with the other to make the peel ply taunt over the tape assisting in smoothing...
   And in areas where it isn't a straight line.. really pull firmly on the tape toward the nearest end, as you roll. This is also rolling in the tape and double checking that work. I prefer working the tape through the peel ply as the roller works smoother and the visibility is good.
   And now double check... triple check.. and check again...
   Don't stop till you drop...
   Use a rag wet with acetone to clean off dribbles.
   I've had some problems with the tape forming lumps and rising off the work... can you spot the void that I found? Just slightly off centre to the right. I know this isn't outgas as it is foam under the tape there and it doesn't gas.
   Only thing to do is reach under and stretch the tape top and bottom. Very tricky as the resin is very gel now.
   Roll firmly..  And got it. Had three spots like this. I'll be speaking to Colan, the maker of the tape about this.
  Where the shear is curved and the peel ply has these high spots... when the resin starts to gel you can make them lay down to make the best surface. see below
   This is near sunset now... and I worked on it till dark and then came back after a beer with a torch and went over it again...
  Next morning..  And in spite of working so hard wound up with an air bubble under the tape. Gassing? Couldn't be.. just too late in the day. I did have some problems in the taping with a few spots that needed me to really insist on laying flat while rolling..
   But anyyway, when I caught it it was early next morning and the resin was still green and mobile. I cut a tiny hole at the top of the bubble and injected it full of resin.
   Then applied a piece of non-stick plastic and a small section of PVC pipe that was about the right contour and braced it against a tent pole. The result was perfect. I could see it with the eye but it was invisible to my touch and that is what will count later.
   So what caused it??? might have been at least partly this. I noticed spots like this in the tape roll I had used. Between this and some rough handling to get the prewetted tape in place fast... who knows but wetting this tape in place would have been a horrendous mess. Also I think the outside curve would have aggravated the result. An inside curve may have had a depression but not air underneath.
   I didn't like the way the sheer ended so included this block of foam to fix up the aesthetics and to provide a buffer for impacts.
   After taping in this is how it looks..

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