Wanted to see if any of the experts could offer me some help… I ride this shortboard from the 80s and I absolutely love it. However, it’s got some major delamination on the deck so I decided to re-glass the damaged portion. Here’s what I have done so far: I cut out the damaged glass with a Dremel Tool and sanded the foam underneath to make it smoother and whiter. Sanding the foam made a slight dip but I went ahead and put a layer of 4oz. cloth and put a coat of lam resin. Obviously, you could still feel the dip so I made a q-cell and lam resin mix and poured it into the dip on the newly-glassed surface. Once it was set, I level-sanded the surface and it looked fine. My original plan was to glass another two layers of 4 oz. cloth to reinforce the area. However, I am starting to think if I’ve done anything wrong, especially with the way I used the q-cell/resin mix on the glassed surface (instead of foam). Do you think the q-cell/resin mix would crack eventually even if I put layers of cloth over it? Should I strip everything out, fill the foam dip with a q-cell/resin mix, and put layers of cloth over the area instead? Please help.
I generally go with Slice one side of the deck open - Pour in a very slow batch of qcell/cabosil/aerosil and resin mix and work it into all the corners. Weight and tape and so on to keep the deck close to the original shape. It is very important to get all the air bubbles out. Sand to the original deck shape, glass a good sized patch over all, usually with 6 or 8 oz. cloth well squeegeed. Sand the edges of the patch, hotcoat past the edges of the cloth and sand edges of the hotcoat down to 600 grit. Usually that’s good enough to go with. It also keeps the original glass, decals and so on better than any other method. For your situation, I think glassing over what you have is gonna be the best answer to the problem. It won’t last forever. No board does unless it’s on a wall. But you’ll get a while longer out of it, which seems to be what you’re looking for. Hope that’s of use. doc…
MT, you have done the right thing, good on ya! The layer of cloth on the foam wasn’t absolutely necessary, but your board will last another lifetime, however long that may be. Hope you get a lot more good waves on it.
nice diagnosis doc,
doc wrote:>>> Pour in a very slow batch of qcell/cabosil/aerosil and > resin mix and work it into all the corners. Weight and > tape and so on to keep the deck close to the original > shape. It is very important to get all the air bubbles > out. I’ve been mixing some glass fibers in when I have to fill larger areas, to hopefully ward off cracks in big chunks of resin. Do you not do this because it makes it difficult to get the air bubbles out? If I mix in more than a little bit of chopped glass, it’s a real pain to work with the filler. I just chop up whatever cloth scraps I have hanging around, cutting the strands to about 1/4" long or so. Just did my first fabric inlay, on a fin. Used info gleaned from here. Cotton print, rotary fabric shear for trimming, little extra styrene for wetting it out, resin tint pinline (okay, maybe a little wider than a pinline…) came out okay. [smile] Thanks! The rotary shear worked so well, I used it on a big patch under the nose of another board (worn through from dragging it across the beach by its rear handle), and won’t be going back to a regular razor blade any time soon. I used S929 resin from Fiberglass Supply. I was worried that it was going to be kind of ugly, but it’s plenty clear enough for me, and I don’t have any trouble sanding it with my Makita 5" random orbital. It actually seems about the same clarity and sanding effort as the Ding All Ultra Clear I’d been using previously, maybe just a little harder to sand. Just ordered the Chicago Electric polisher from Harbor Freight for $25. Should be nicer than my 6" synthetic wool pad and ancient Craftsman 3/8" drill setup. I’ll be sure to open it up and put some real grease on the gears before using it. [smile] Great resource, this site… http://vma.cape.com/~patrick/lifeguard/repair/dbd_n4/dbd_n4.html
Patrick… GREAT JOB!!! I love seeing a beat up piece of shit brought back to it’s full (and then some) glory.
Hi Patrick, how’s the holiday going for you? You’ve set up quite a nice little shop there. Lets see - I avoid including glass fiber in filler because it does tend to hinder a good fill job when it’s poured, as you mention, plus it’s misery to sand. If you’re glassing over it, I think it’s probably unnecessary, leastwise I haven’t had any problems. Resin- I think you’ll find that resin is pretty much resin, though the Fiberglass Supply stuff is likely to be a bit fresher and more reliable than the stuff you find in surf shops. I have a couple gallons kicking around if you run short. That Chicago Electric polisher ( http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=46507 is it?) - I think you’ll be happy with that, plus the 5/8" - 11 spindle will let you go to a power pad or something similar ( I use the 3M pads ) and stick-on 8" discs which will make big sanding jobs SO much easier. Or there’s a 3M polishing pad system that’s good too. One thing, you’ve entered a new world of power in power tools with that, so you may want to bungee the boards down on your repair stand - I fired a few boards across the room before I got smart about that. Rotary shear; is that one of the Olfas ( I may have misspelled that )? I have been backing into the sail repair/boat canvas biz of late and anything that’ll cut glass cloth will likely do just fine with canvas and Dacron sailcloth and Sunbrella acrylic. So, what’s your fiendish plot for fixing those paddleboard decks? A couple of ideas occurred to me while writing this, especially as you have the glass off 'em. I’ll be around the house, stop by if you’re in the neighborhood doc…
Thanks, John. Yeah, that board was pretty banged up around the edges. It seems a shame to junk a basically sound board when all it really needs is a little attention here and there. New ones cost the town at least $900 a shot too, and spending my nights and weekends working on boards at home keeps me out of trouble. So there are good reasons all around to keep the old boards in service as long as possible. Doc, the holidays are going fine. You? There’s a polar bear swim at Corporation on New Year’s day. I may throw on my wetsuit and paddle out to guard for that just for laughs. I was going to be up your way today because it looked like we’d have waves this morning, but I just couldn’t get out of bed before the tide came up. Then about the time the Beachcomber web camera was showing the waves shaping up again in the afternoon, we had about half an hour of light left. Bah. Thanks for the head’s up on the bungee cord idea. Sounds like a good plan. I didn’t realize how big those 7" polishers are until I saw a Milwaukee at Home Depot after I’d already ordered the Chicago Electric from HF. The model you linked to is the one I’d ordered. Those are big tools! I can’t imagine working on a little 6 or 7 foot surfboard with one of those. It really would launch it right off the stands if you caught it wrong. Luckily, the boards I work on weigh in around 30 or 40 pounds, so they might stay put a little better. [wink] So… my plan for the red boards is to sand the foam until it’s maybe 1/8" or so down and mostly flat, fill the bigger craters with vinylester resin and microballoons, then a layer of 8HS weave 9oz cloth, a layer of 2mm thick Coremat, another layer of 8HS weave 9oz, all wetted out with vinylester. I wanted to go with epoxy, but it really needs to be something that can deal with sitting on the sand all day in the sun, and the heat deflection temps on the room temp cure epoxys seem to top out around 130ish. I know some days the boards get at least that hot. Then, to cover up the uuuuugly vinylester, I’ll likely make a deck pad of some 3/8" thick EVA foam sheet glued down with 3M Super 90. Initially, I was going to put fabric inlays over the whole section. I even picked up a couple of pieces of cloth with patterns that seemed like they’d look good. But the more I put those pieces of cloth over the boards and picture the final result, the less I like it. A big red board with a white cross is a pretty pure thing. Putting a fabric inlay on it just… doesn’t look right to me. I think a foam deck pad cut to a decent shape would fly though. The red boards with delams that I went through last winter, they didn’t hold up at all. I’d drilled both ends of the delams, injected resin and worked it through until it came out the other end, taped over the holes and weighted everything down until it cured… they looked fine when I was done with them. But three weeks into the summer, they were starting to delam again. No good at all. So this time around, I’m just cutting the decks clean off and having at it from fresh foam. I’m going with vinylester mostly because I’m curious. I’ve never worked with it before. The numbers kind of point to it for durability and heat tolerance, so… How were you thinking of coming at it? http://vma.cape.com/~patrick/lifeguard/home.html
Hey, Patrick Yeah, real good day for the ‘long winter’s nap’ of the poem. Me, I got some reading done and sleep and that was just fine. Lets see - bungee should be fairly heavy stuff, or I can give you some nylon webbing and a buckle, nail that to the stands and you can belt 'em right in. What am I doing with that stuff? We decided that there were no good soft surfboard racks available for sale that were suitable for rental use and abuse, so I am making a bunch up for next summer. When I get going I’ll put together some how-to pages and pics. Oh, and if you get some carpet underlayment and put that on said ding stands, that helps too, gives it a little traction. As you’re indoors, it won’t dry up and die like it will on my usual outside repair stands. Lets see- I haven’t worked with vinyl ester, though I’m given to understand it tends to have a kind of blush, like boat resin. You might want to try a test before going with it for a final coat. Should be plenty good enough for everything else though. Now, the idea I had was, rather than sanding the foam, get a router, a straight bit and a piece of 3/4 ply twice the width of the boards and, oh, a foot wide. Drill the holes appropriately so you can make it into a really big base plate for the router. You can also do something cute with a PVC pipe elbow and a shop vac so that you’re not blasting foam dust all over. If the cutouts kinda take a dive downwards, hot-glue a couple of wood strips on to give your giant router base something to ride on that’s flat and level. Taking it side to side and slowly moving forward, rout out the old foam to a uniform depth, depending on the foam thickness you can get minus about 1/4". That is, rout 3/4" deep if you can get 1" foam. Then, stick in some new sheet foam ( try Gorilla glue as your adhesive, it’s basicly a urethane foam adhesive, catalysed with moisture ) and then shape the stuff to match deck shape. Use the toughest, densest foam you can find that’s compatible with polyester resins, there is one ( Divinycell? ) that comes in varying thicknesses and densities and is used in homebuilt aircraft construction. Then, glass over it until you get tired of glassing over it - I’d go with a minimum of 3x10oz with Ace Hardware red paint pigment in the resin - good match for the Lifeguard Red. Afterwards, find a way to keep those dark red boards out of the sun somehow, 'cos just a little use will start the whole process again. It’s the sun that’s killing those boards, that and plain abuse. Plus foam deck knee/paddling pads. Could be you can do a red cross inlaid into those foam deck pads, no? The advantages are that this will be one hell of a sight lighter and less work and the denser foam is going to make a nice intermediate layer between the soft blank foam and the abused deck. That make sense? Router - if you don’t have one you can either get one from Harbor Freight or at the Used Tool Store in Hyannis, right next to the Blockbuster Video I think, by the Mercedes place. I saw a few in there the other day. As for the Polar Bear Club…gah. I’ll be fifty next summer, and I don’t really think I’d be up for it. One suggestion- have hot spicy soup in your thermos, not coffee. Capsicum is a nice vasodilator… Back to the land of nod… doc…
Doc, Patrick, I use v/ester resin at the boatyard I work at,and have glassed my last 2 boards with it. It is a far superior resin to polyester. It has similar chemical properties to epoxy but works like poly.It is brown and goes off brown.This is why I used it on my boards, they are old school shapes and I wanted them to look old,cut laps and pinlines. You need to use mekp/sr (slow reaction) you can use regular mekp but it will gas up the resin. It is compatible with poly so laminate with the v/ester and finish with s/board poly.I have not used it with pigments yet, could be a bit of a problem with the lighter colours I think.The resin we use at work is Derakane SPV Vinylester made by Dow Chemical co.Hope this helps, David.
Hi David, Thanks for the tips - do you find that a vinyl ester lamination is more or less stiff than an equivalent polyester lamination? Best regards doc…
Hi Doc, I think you will get a stiffer laminate with v/ester. But with the thin laminates used on surfboards it would be hard to tell. I went through all the tech info I have on it and it says that the laminates will be stiffer than poly.It also has a higher tensile and interlaminar shear strength than poly. Having said that, my 9’6" glassed with 2x10 oz on the deck and 1x10 oz on the bottom, still flexes when paddling through chop. I make alot of fins with v/ester and I have been able to get the glass to resin ratio down to 1.5 : 1. This allows for a fair amount of flex in the fin but the resin will not fail under load the same way poly will. It is also lighter than poly.Hope all this helps.David.