Delam at resin injection spots

General Discussion
1

Hi everyone, I’m going to be trying to fix a delam (maybe a couple) on a board that the prior owner injected with marine resin as a temporary fix. He didn’t glass over the holes and one was not water tight. I’ve cut it open and dried it out (see pics) but not sure what to do about the injected resin “mounds” - the ones that are surrounded by delam I’m assuming I should cut out, but a couple of them feel pretty good actually. Is it much better to have a square or big oval work space or would cutting out a more intricate shape be fine? In the pic with glass cut out, the top right couple plugs are okay. 

 

For the other problem areas, not sure exactly how to proceed - cut out all these holes and start new with microballoon and q cel? just fix the one that I’ve already cut and leave the rest? or add some glass on top of the holes that are still watertight even though there’s some light delam around them to make sure they stay sealed? I get this sounds like a lot of work but board is worth it.

thank you! 

3bet

 



2

Okay, first-

Put the knife down and unplug the router. Cut as little as possible. Save whatever you cut. 

Presuming this is a polyester resin/polyurethane foam board, though I’ll add epoxy/styrene foam methods too.

For the big delams, maybe slice three sides, open it up and dry it out, don’t use a heat gun, that will make the delam spread… When it dries, fill (indeed overfill) with resin-filler mixture, catalysed light. You want to put in a lot so you get no air bubbles in there.

You don’'t want this getting hot as it goes off, see ‘delam spread’ earlier… Let the flap down and hold it in place with something, a weight or a strap or lots of tape, over wax paper. Let the excess filler come out around the edges.

Resist the urge to futz with it. You will only get air in under the old cloth, which is bad.

If it’s epoxy/styrene foam, open it up as above, but set it in a way that the water that got into the styrene foam, and it did, can drain by gravity. You won’t get it all, but be patient. Do the same with filler/resin mix but do up the epoxy exactly as the directions say. Replace the flap or cut-out piece as above and I would stash it someplace cool and dark until the resin/filler hardens. 

Sand the excess filler flush with the deck. Lightly sand the area, clean it off dust free. Glass over the area, overlapping to undamaged un delammed area… Go thick as needed to bring it to a nice smooth surface if your original glass is a little low when it went back in., hotcoat, sand, gloss, sand and polish as needed. 

This way, you don’t have to attempt a color match, a trick that never works. You don’t have (we hope) a your patch sitting there like a wart over the whole thing. You may see a little filler outline around the original glass, that’s acceptable. 

As for where previous owner went muts with the boat resin botox treatment- look, by the time you go drilling and refilling and all that, I think you’ll only make it ugly. Unless you are really really good and really really lucky.

Sand the resin down flush that’s excess at the resin injection sites, lightly glass over, feather the edge of your patch and hotcoat/gloss as needed. It won’t be perfect but it won’t be worse and in this that’s about the best you will get

hope that’s of use

doc…

3

Thank you Doc, that’s all of tremendous use! If you’re up for it, I’ve got a couple questions just to clarify…

  1. Is the benefit of not cutting the glass out just to help things from getting ugly? I care ZERO about appearances on this thing (that ship has sailed ha) and I’m most interested in the fix that might last longest. 

  2. For the one that’s open already, I was thinking of putting a layer of 4oz glass directly on sanded foam surface, resin/filler mix over, then two more layers of 4oz to get smooth/flush with rest of the board. Does that make sense?

  3. the slice and fill method sound great. How do I make sure my resin doesn’t get too hot?

  4. for the areas that are botoxed (ha) but still holding, there are some soft spots around hard spots - you think it’s fine to just glass over it all and leave the soft spots alone for the time being? If I’m not worried about looks is this still the way to go? I guess I can always “drill and fill” down the line but feels weird to kick the can!

Thanks again for all your insight, it was extremely helpful doc.

3bet

4

Let’s see- in order

1- There are several benefits. The first is appearance, definitely, if the color comes from airbrush on foam especially. For those it’s about the only way possible. But consider strength. If your new cloth is bridging a very small gap, tying it together, it’s going to be less stressed than covering a wide gap or a missing area. 

2- That open area- I would ( if you tossed the old glass piece, if you didn’t, use it) make up a batch of filler/resin mix about the consistency of- oh- peanut butter ( not the chunky kind)  or mayonnaise and use something with a straight edge to fill the cutout, surface right even with the surface of the board… You don’t gain any strength encapsulating the filler, indeed you’re making a stiff area that can crack or pop off as the board flexes a little in use. It won’t help adhesion either.

Look, what sticks glass to foam is pretty minimal, and that’s just to the very top of the foam. The foam is held lightly and flexes easily while the real strength and stiffness is in the glass skin.Add something stiff that flexes differently and is only stuck to the foam lightly, not great…  

3- Okay, resin curing is an exothermic reaction. It gives off heat. A given amount of resin curing will give off a certain fixed amount of heat, per gram or per cc or whatever. Now, the speed at which the reaction goes is also driven by heat; most reactions are, the warmer it is the faster it goes off. If it gets too hot it gets brittle and I have seen some ( we did it intentionally most of the time) catch fire. 

A thin layer of resin, like glassing,  well, that heat radiates easily, it doesn’t overcook. But a thicker layer of resin, say mixed with filler, that heats up quite well and then the reaction goes faster, so it heats up even more - see where this is going?. A really big thick ‘plug’ of filler can overheat and crack and they do. With polyester resin, use the minimum amount of catalyst, mix very thoroughly. Epoxy, the ratio of part 1 to part 2 you can’t change, so instead keep it cool and out of the sun.

4- It is what it is, I’m afraid. I’m not going to say it’s fine but it’s the best you can reasonably get. This board won’t last forever, none do, and the clock really started ticking when a leaky ding or several.went unfixed. And what you’re doing is a patch, not a cure. Surf it until it dies, or until you add it to your personal museum or hand it off to somebody else. If this was one of (insert famous name here)'s favorite boards, it might be that somebody would think it worth restoring perfectly and putting on display. But it’s not and it’ll have to suffer the fate most boards do.

Sorry about that

hope that’s of use

doc…

5

Thanks for taking the time to answer so thoroughly doc, that’s all very helpful!

6

Hi Doc, little update. One of those Botox holes on the outskirts of that big cluster of them started “crying” when I stood the board up. A couple drops coming out occasionally. I basically cut out the tiny resin plug and put it upside down to hopefully drain as much as possible. At this point, is the original plan to sand and glass, off the table? Do I need to cut out a little glass (and keep it this time!) or flap to expose the foam and let it dry? Thanks!

 

7

Okay, is this a styro/epoxy board? If so, I would set it (blocks and shims and so on) so that the large-ish piece you cut out is the lowest point on the board and leave it to drain. It’s the biggest and easiest exit. Draining, I’m afraid, may be quite a while - set some newspaper under it so you can see when it stops dripping. 

Where did the water get in in the first place?

doc…

8

No, it’s PU actually. I think the act of fixing the prior delam from compression (that was probably still watertight) by puncturing and then squirting resin in is what let water in. No glass over the punctures so I believe they’re the entry point.

9

Ohhhkay. Well, this is why doing it that way is a really bad idea. Gah. Injecting ugly mysto resin all the way through the board to fix a delam. Jeez. Would have been better off using botox.

So, what would I do? Break out the drill. Drill out the botox clusterfuc# holes the previous guy did, slightly bigger. If one leaked, probably they all do. I’d suggest a nice, new, sharp steel twist drill bit.

Let it drain while cursing him. It will still be a while. Work on your profanity. The combinations are mportant. Contemplate clubbing him like a seal. Wonder what was going through his tiny mind to do it that way. Be glad when you can’t understand why.

I can’t understand why he did that and I already feel better about myself. Sheesh. My standards have obviously slipped. 

Then, get yourself some ‘white’ gorilla glue, the ‘foaming’ kind and shoot that into the holes, masking tape over to hopefully give it a little compression. Let that go off - it’s water-catalysed. Usually you would dab a little water in there, it won’t be necessary this time. Sand flat, glass over. Instead of snot-brown round things you will have bright white round things. If you’re good with color, say, watercolors, a little wiped into the foam may help hide it a touch, it wil only get into the foam. Wipe on with a paper towel, wipe off with a clean one, like you would with wood stain doing trim or furniture. 

As before, you will be tempted to hit it with heat to speed up the drying. Don’t. That way lies delams*. Vacuum, well, it’s a thought but maybe you could make things a lot worse quite fast. Gravity is probably your best friend here, followed by a good command of cuss words. 

Hope hat’s of use

doc

  • Heat. Perversely, gentle heat can be useful for pressure dings sometimes, when the foam gets pushed in. Sometimes something warm, say towels dipped in quite hot water and wrung out well, that can re-expand the foam a bit. And that would have helped with the original delam.
10

Doc you’re like an encyclopedia with this stuff! Someone should compile all your insights and make a Doc’s ding repair book. Not sure it can be me, but someone!

I’m guessing I’ll need to add a little water IF I’m successful in drying out the holes right? And don’t worry, I’ve got it in a warm room in the shade. No heat guns or direct sunlight for me. I’m in no rush. Thanks for my marching orders

11

Ah - first off, let me commend to your attention Swaylopedia: https://www.swaylocks.com/swaylopedia/index.cgi?Recent_Changes . While it’s perhaps (in my opinion, anyways)  lost its way a little in recent years, the original work by Keith Melville and John Mellor and others holds up. It’s potentially a valuable resource and should be constantly evolving. A lot of entries are place-holders, needing to be filled in. Many entries probably could stand updating. And the world moves on, new things come up. 

It is NOT someplace for people to put photos of their latest work. But it IS a place for subject matter experts to tell the rest of us all about what they do very well, so that they don’t have to rewrite answers again and again.

Yeah, guys, this means you. 

Anyhow- I must have written that last reply unclearly. Not the first time, won’t be the last. I wouldn’t worry about wetting the foam for the glue. Rather, it’s not that probable that the foam will finally be so bone dry that you need to put in a faint bit of moisture. Unless you live in the Atacama Desert, you’re going to have a fair amount of moisture left. But the glue should at least seal it off as well as it can be sealed.

I hope I did better this time-

doc…

12

Crystal clear!