Getting close to putting the glass on the deck of my WD12 Hybrid and I’ve noticed that when doing the finish sanding that the “sand” fills in all the little voids I have between strips. I’m tempted to leave this filler in place, just lightly wiped down the deck without vacuuming , and lightly paint on my epoxy seal coat. Might this work or is all the wood dust filler going to get pulled up onto the surface?
I feel like this might be a big mistake but the deck look so much better before I vacuum and all the little gaps are revealed.
~Ron
I’m assuming you are talking about a few small gaps of 1/16 inch or less? I think it would be best to remove all the dust. When you apply the glass and epoxy, the epoxy will fill all those little gaps and you won’t see them. If you do leave the dust there, it will not be as strong, and the epoxy will make that dust much darker than the solid wood leaving dark marks.
Hi Ron,
if you have little crack between strips as you describe, there is a technique for making them disappear…such that when you apply your seal coat and ultimately glass it, it will look like the strips mate perfectly …vs the little black hair lines that will show up if you don’t address them.
i guess what i am saying, is i disagree with peter that they will disappear…unless the woods you are using are already dark or if the gaps are between a light strip and a dark strip (in which case the gap will appear part of the dark wood).
in my experience, most lightly colored strip jobs look nicer if you fill these little voids.
the approach to filling them is pretty easy…and is decribed by Nick Schade in one of his books or building videos and i use this technique extensively in my builds as the part of final getting ready for glassing.
basically what you do is put a pinpoint line of wood glue into these little gaps, you can press the glue into the gap with a popsicle stick with a flat edge…and than wait about thirty seconds, after that, run a 80 grit sanding block in the same direction as the strips with a slight motion moving from the darker strip to the lighter strip. the ‘sawdust’ from the strip will mix in with the wood glue giving a putty that matches the strip…and make the little gap disappear. wood glue will not turn the sawdust dark…you will get a pretty good color match that will hold up after epoxy is applied.
in this technique, it important to not overdo it with the glue, and do make sure you have sanded the glue off the outward facing part of the strip. it adds a couple hours of work to the project but i find it worth it in the final result.
howard
Yes Peter, gaps are 1/16 or less. See photos. My experience has been that these type of gaps will disappear between dark walnut strips with but with red or yellow cedar they become more noticeable when the epoxy and glass go on. I’ve used epoxy thickened with wood flour or dust from sanding to fill larger gaps and then have to sand them down. I tend to be a bit “annal” with my boatwork and was hoping that just leaving the wood dust in there would be a shortcut versus filling and sanding every little gap that I find.
Hi Ron, here are two pictures that show the results of the technique i am describing. the first picture you can see lots of little gaps:
the second picture the gaps pretty much disappear. this technique is good for about a 16th of an inch gap or smaller.
i realize its hard to see…fwiw…i share your ‘anal’ perspective.
h
Thanks Howard. That sounds like what I need to do. I seem to recall seeing something from Nick where he used blue painters tape on each side of the gap to create a very narrow work zone to apply the glue and sawdust. I was hoping to cheat and just leave the dust in gaps that is already in place but sounds like the wood glue is the better approach.
Guess I’ll have something to keep me busy for a few hours this weekend. 
It can actually be kind of zen and relaxing…a little practice and you will get the hang of it…larger gaps may take a second pass…
Blue tape can help keep it clean but i use a little glue bottle just for this with a sharp point
Let us know how it goes
Spent a couple hours taping and filling gaps with a mix if yellow wood glue and sanddust. Another hour removing tape and sanding. Results are looking good. Of course with my neurosis, I see more gaps while I’ve been sanding these first gaps but so far I’m able to resist making another pass to try and fix every little spot.
~Ron
