I tried filling in a delam yesterday and it did not go so well. The edes still have airpockets and the center where I cut open a little slit dried unevenly because I was pouring into one side and when I was going to pour into the other the resin/q-cel combo was to stiff to pour in. So now one side of the board is higher then the other and the spot and the spot where I slit does not line up. Is it a bad idea to just sand away all the glass on the delam and smooth in some resin/q-cell combo over the faom with a squeege, spraypaint red to match board, then glass over the whole area? What are the disadvantages of doing this? What problems can I run into in the long run? Is it better to leave it how it is, make more slits to fill the other airpockets and glass over the uneven spot.? The dealam is about 1 foot where my knee goes when I duck dive. Its going to be covered by a tail pad so looks is not that much of an issue.
Has anyone tried using expanding foam that you can buy at the hard ware store to fill a delam? I need to save my board. I am thinking about just striping off all the glass and filling the foam in properly.
I goofed on a future fin router(all the way to the deck). Installed the box then backfilled the cavity with polyurethane expandable foam insulation. Not as dense as the foam blank. Long story,but last I heard the kid I gave the board to was still riding it. Its been a year.mike
This is a variation of the way Doc does it. When filling delams using the slit’n pour method, I always use straight lam resin (slow cure). Use small wood wedges to hold the slit open. It’s best to way overfill the slit and then tape it shut. You also need a helper to tip and rock the board around to distribute the resin. Once the resin is evenly distributed, you need to clamp the delam area down. This will probably squeeze out a lot of resin, so mask around the slit with wide tape/wax paper. I lay a couple of short 2x4’s on the affected area lengthwise with the board. I then use more 2x4’s across the first ones slightly longer than the width of the board. Put small bar or woodworking clamps on each end of the crosswise boards and apply light pressure to drive down the first 2x4’s. Put some plywood under the clamps so you don’t dent the bottom of the board. Let it cure for 3 or 4 hours and remove the clamps. Scrape off excess resin. Hotcoat fill to even the surface up or use filler if there was a lot of foot dents. Sand it level and laminate a layer of 6 oz. overlapping 2" on to the good glass. Hotcoat, sand, etc. Alot of work, but delam’s are the most difficult and tricky repair there is.
Forget using the foaming goo in the can from the hardware store, it’s not dense enough. You can use 2 or 4lb density “pour foam” (US Composites, FL) but you can’t inject this stuff either. It’s to thick and won’t distribute properly (2 min work time). I use it on restorations with severly rotted foam. I cut off a section of the deck glass, router down a couple of inches and put a layer of this stuff on. It expands 5x, and I plane it down to 1/2" below the desired surface. It’s full of big holes due the foaming action of the product, so you can’t directly glass on it. I laminate a 1/2" sheet of urethane foam over it, shape that, then glass as normal.
For your current situation, it sound like you have a partially filled delam repair and a big mess. If the foam isn’t pounded down too deep, you could cut off the deck section and fill with resin/cabosil (very thick mix). Q-cell will be too runny and heavy. Sand it down then cloth the area. Don’t try using spray paint (unless it’s acrylic) with resins; you’ll just have another mess to deal with.
This is a variation of the way Doc does it. <edited - I’d call it an improvement over the way I do it - thanks, Pete > Alot of work, but delam’s are the most difficult and tricky repair there is.
For your current situation, it sound like you have a partially filled delam repair and a big mess. If the foam isn’t pounded down too deep, you could cut off the deck section and fill with resin/cabosil (very thick mix). Q-cell will be too runny and heavy. Sand it down then cloth the area. Don’t try using spray paint (unless it’s acrylic) with resins; you’ll just have another mess to deal with.
I hate doing delams. If you don’t do it perfectly, it’ll either be a partially filled mess or it’ll fail and the delam will spread. If there’s a deck pad over it, forget the paint, it’ll just complicate the issue and there’s more than enough problem there now.
hope that’s of use
doc…
I had pretty good success with a delam repair on a 9’6" Iron Cross. Following some tips gleaned from the site I used a Dremel tool to cut around the delam and carefully pulled up the glass, about 2 feet long and from rail to stringer on both sides. I filled any gaps along the rails, then coated the foam and replaced the cut outs. I weighed them down with filled plastic bags of gravel and let it set. Then I cut glass about 2" beyond the edged (across the stringer) and poured the resin and wrapped it with saran plastic wrap. I wasn’t looking for aesthetics as it was the deck and would be covered with wax, but it’s been about a year and has held up great.
D