1. Yes. When you sand the edge material off you'll expose new gaps even if you've filled the edges.

2. Yes, round all edges.

Have fun,

Laszlo

Laszlo,

Many thanks for your reply! I'm sure I'll post other questions as I overthink things.

Chris

   Chris

I'm starting getting ready for my first build (a Sassafras 14) and when I get to the sheathing, I'm giving serious thought to priming the hull in CPES

I think that in the States it is sold by someone called Rot Doctor. It is a Clear Penetrating Epoxy Sealer and epoxy resin bonds with timber treated by it very well

Just something for you to consider

I tend to overthink things too :)

Tony

   I finished stripping my Nymph canoe and am presently sanding the hull. I am finding some gaps between the scarf joints and have read several articles regarding filling them. Should I tape around the gaps with masking tape then fill them with epoxy/resin and sand them prior to glassing? Should I epoxy the entire hull (as suggested by some) prior to glassing to fill in the gaps with epoxy and 'prep the wood' prior to glassing to prevent bubbling as the epoxy fills in the wood? This process seems would fill in the scarf gaps as well, eliminating the need to individually fill in any gaps prior to glassing. I also read that the epoxy will 'color' the wood and will be seen through the fiberglass which seems to me will enhance the 'flaws' in the stripping process if I individually fill in the gaps with epoxy. This is my first boat build and experience with epoxy and glassing so any advice is greatly appreciated. Many thanks!

   Generally speaking, you want to fill any gaps that you have in a strip build.  For the biggest gaps, use a razor knife to cut a sliver from the same color wood and glue in place with wood glue.  For the smaller gaps, fill with a paste made from epoxy and wood flour.  Unthickened epoxy won't fill the gaps.  Some try to use saw dust from the same wood but I have pretty good luck with wood flour.  For lighter colored wood, I mix in a bit of cell-o-fill with the wood flour.  Experiment to find the color that you want.  No need to mask, just fill the gap and wipe it flush with a putty knife.  Sand over once it is cured.  Don't worry too much about getting the color exact.  The overall beauty of the boat hides many small imperfections.

Once you have the entire boat sanded, wet down with a wet rag (water) to raise the wood grain, then once dry sand lightly with 220 grit.  The wet-out also closes the staple holes making them less visible.  Some like to coat with epoxy prior to glass but I am not convinced that it really helps.       

Many thanks for the suggestions...I will try the 'wood paste' to fill in some small gaps prior to glassing. I also want to add a second layer of glass over the 'football' of my canoe to add extra strength. I read that it is advisable to add the second layer after the whole canoe is glassed since the epoxy is easier to apply over the fully glassed boat rather than have to deal with a 'seam' at the smaller section applied to the football. Agree?   

agreed,

it's best/easier to do the football after the initial glassing of the hull.  its a lot easier to get a clean, easier to fair in edge of new glass over cured glass than the other way around.

h  

Excellent advice from all above. I do carry a couple of steps a bit further though. After wetting the wood and finish sanding with 220 grit, vacuum the wood to expose all the tiny flaws you just filled with sawdust. I save my ROS dust in two containers, light dust and dark dust. I mix epoxy with a combination of the two to most match the boat then apply a coat of this "mayonaise" paste to the entire boat. This fills the small voids and seals the wood.

Wood will outgass and ruin your glass. There are two ways to prevent this. Either seal the wood before applying the glass or heat the shop up to 75-80 degrees and let everything heat soak for awhile then turn the heat down so everything is cooling off when you apply the glass. This way the wood is 'inhaling' instead of 'exhaling'.    

Wood will soak up a lot of epoxy. It may look good as you squeegie off the excess epoxy and move on but after you leave, the wood will suck down epoxy at different rates depending on the tightness of the grain leaving white spots in the glass of epoxy starved areas. Pre-sealing the wood stops this.   

As soon as the seal coat is dry, lightly sand with 220 again to remove any roughness and apply the first coat of cloth. As soon as this is dry enough to drag cloth across it withoug sticking apply your "football" glass.  For me this is an all day job but it ensures all cloth layers will bond together with no possible blush forming on the epoxy.