I am going to add a layer of glass over a previously finished board bottom only, and it has boxes installed. My plan is to tape the inside of the long single box to cover the slot then add a generous coat of silicon or vaseline to keep the epoxy resin for more protection from messing up the box. The side boxes are probox, so I will do the same. I want the glass to cover part of the boxes, but I also want to be able to use them and I don’t want to have to route out the slots after. Just clean up the edge if needed with a razor and file.
I saw a post from McDing or someone that said something about filling them with flour. Not sure how that works.
since McDing posted about the flower trick i have tried it a few times and it works great, but just taping off the boxes are alot quicker for me so thats what im sticking to
Actually I was planning on taping the insides (just the slot) to get the glass to cover as much of the box as I can. It’s not important, but I thought it might look cool if the glass was all the way to the slot. Just taping over the slot would be easiest, but I wanted to try something different. Kinda like the way popouts look. When I tape over the slot there’s a small edge/lip where the tape was, then part of the box that was covered. I guess I could use a small grinder or sander and smooth that out better.
I was planning to carefully get the tape down into the slot of the long box then push it on to the sides, then add a piece across the middle, then add the lubricant over the tape to keep resin from getting past that. The tape would be up to the very top of the slot, but not on the bottom surface of the board. Once the resin is hard enough I’ll cut the slot open, then after it’s cured I can remove the tape and clean off the edge of the slot. For the Proboxes, I’ll put the lubricant on the insert then tape over the slot just to the edge of the insert. I want to be able to remove the cant inserts.
Actually, with FinsUnlimited boxes, you don't even need to tape off the slot. No resin drips in, and what little that does, is easily removed with a file, since it won't really stick to the sides if you do it before 6 hours.
Just place the dry glass over the box, squeegee it lightly over the slot, saturate the rest, allow cure, cut with razor blade, and you cap the box all the way to the slot without any problem. The resin just stays on the glass and doesn't drip down the insides of the box, if you LIGHTLY saturate the resin over the slot. The way to do this is to saturate the area outside the box first, leaving maybe an inch, then lightly squeegee over the slot.
I was also thinking that I might be able to use a brush to wet out the glass, or at least parts. I plan to add a generous cut lap over to the deck, and I was thinking I’d try using a brush on the rails instead of the squeegee. I could use the brush to wet out the area around the boxes.
Just taping the box is fine. But if you are attempting to put as much of the box under the glass as possible; The flour trick would make double sure you didn’t get any drips or puddles inside the boxes. When I used to do ding repair on Maui and was laying a layer of glass over the box; I would usually just tape them off and then use a nice straight edge and sharp razor to trim up my tape to a minmum over the slot. If you aren’t careful though you can move the tape while squeeging the resin over the slot. That might result in a drip or puddle of resin in the box which you would have to clean up later. Pack the box with flour. Wipe the edge of the box real clean so that the tape will stick and tape over it. It’s just extra insurance. Lowel.
I would add this; If you are opaqueing or doing a tint over an old board and want just the slots; the flour is the way to go. Don’t even tape the slot or inside the box. Just fill them with flour and pack it down into the box with a popsicle stick or pencil eraser. No tape. When your Opaque is set up and hotcoated cut out the slots with a Stanley knife and blow out the the flour with an air compressor. Grind lightly around the inside edge of the slot with a Dremel… For the gloss I would just tape right at the edge of the slot and trim it up with a straight edge. Lowel
If you’re careful doing an ‘‘after-the-sand job’’ patch you don’t need to tape or fill the boxes or anything; just don’t pull heaps of resin across the box and none will drip through the cloth.
I’m going to add a complete layer of glass over a board that has several bad spots along the rail. When I was sanding it I also noticed that it is very soft along the edge about an inch from the rail running up the board a ways, so I don’t think this one’s gonna last without a fix. I sanded it down to the weave, but I’m worried about the boxes getting messed up. This board has one inch wide Blue Dow foam rails, so it must have swelled some during the sanding and the glass got over sanded. Not sure, but it was really soft yet it doesn’t look like I sanded through the glass.
Done this several times. It works. Just be sure… like Lee said… don’t force the resin through the cloth. Then you can hotcoat right over it, too. Easy trim with a razor blade to finish it off, then deburr the edge with fine grit paper.
…I can add that you need to be very careful when you use the razor blade in the edges of the slot; if you do not do it right the fiberglass will delaminate from the box in several spots, no matter if the top of the box was sanded rough.
Like Lee and nj said, you don’t have to tape off the box. I cap every box and with double 4oz and never tape or fill it with anything. Just lam normal but be gentle when going over the slot. Hotcoat, sand, gloss, and polish normal. Then use a trim router with a 1/8" flush trim router bit after the board is done (put masking tape next to the box where the router goes to keep from scratching the gloss) and give it a little bevel with sandpaper on a paint stick. . The result is clean.
If you’re scared you can coat some PVA in the box before you sand prior to glassing but you really don’t need to take that precaution.