Heavy Glass Job Denting Very Easily

First post here, thought I’d gather some opinions on this situation from some shapers/glassers. Just recieved a custom board, super excited, it came out great and it’s beautiful. For added durability went with a heavy glass job + deck patch, totaling 16 oz on the deck, volan glass etc. Since this is not a performance board, I figured it’d be fine to add some extra weight with the hopes of creating a more durable board. Took it out for a surf in a mellow, waist high crumbling waves, and cruised it real easy, took a total of about 10-15 rides or so. I get back to the car and as I’m loading the board in notice a solid heel dent, basically two dents combined into one heel size depression under the front foot area. Same on back foot, however less noticeable (guess I really surf off the front foot lol). For a standard shortboard this is to be expected, but with the heavy glass job I couldn’t believe it - I only weigh 150 lbs, my shortboards don’t even dent all that much, and I was wearing 7mm booties which in my experience absorb a lot of force underfoot. Spoke to the shaper, nice dude, and he agrees it’s unusual and hasn’t really happened to his boards before - we are thinking that it may not have cured fully? The board sat for approximately 9 days or so between shaping and this session. I noticed two days before taking it out that it still smelled slightly of resin when up close to it. Could this be possible that the resin was still soft enough to compress the foam? Could it be a bad blank? A materials issue or just not enough cure time? Dents are dents, they’re bound to happen eventually, but its a bummer bc its a beautiful board now with a big noticable depression right in the middle of the deck and it seems its not really due to normal “wear and tear,” but due to a materials issue. Any thoughts? 

First off, volan is just the type of finish applied to the glass after weaving. It acts as a binder to allow the resin to stick to the glass. It really doesn’t affect strength in any way. The weave of the cloth and weight (6,8,10 oz) is where the strength comes from.

It’s pretty surprising that you got dents while wearing 7mm boots. Barefoot? Big difference.

I would guess that the blank is the issue. While extra glass on the deck is always beneficial for added strength the foam underneath is the main determinant in compression strength.

Letting it cure a liitle longer may have made a difference but I suspect the foam is the cause. Did the shaper say what blank he used?

Ahh good to know about volan - seems to be a bit of word of mouth misinformation out there about this. Just to be clear, the shaper didn’t tell me that volan is stronger, it was implied to me by a shop dude a while back.

No idea what blank was used - but knowning this guy, I doubt there was any compromise as he’s really in it for the right reasons and pretty well respected, craftsmanship on all I’ve seen is top notch. That being said I suppose “bad blanks” do exist and can crop up from even the trusted suppliers. The stringer looks to be darker than standard, but I’m sure many blank companies offer dark stringers. We basically left it at an agreement that if it continues happening at this rate, he will shape me a new board.

From US BLANKS catalog. Less density = lighter weight, dents easier. Many people prefer the lighter weight and consider foot wells worth the trade off. Some even like foot wells.

Agree with SammyA- the blank isn’t up to snuff. Two layers of 8 oz. cloth shouldn’t have done that, especially at your weight wearing 7mm boots unless you have stiletto heels on said boots.

A little ‘glassing smell’ is more or less normal. While it may be that the blank sat for what, nine days? , how long since it was glassed and what kind of temperatures was it in during that time? A week, no problem, unless it was left in refrigerator temperatures, a couple of days and left in temps under , say, 60°F, problem. The time-to-cure/pot life versus temperature graph for polyester resin takes a whoop around 50-60°F. If that’s the case, bring it in out of the cold for a few days, see if it stiffens up some.

And the color of the stringer, no- likely a different batch of wood but it’s gonna have about the same effect as a different color in pinstriping, say.

One other possibility- Molded foam blanks tend to be densest at the surface, going softer as you get towards the center. Strengthwise, this is a very good thing, you get the density where you need it and some, not terribly relevant, weight savings. But it’s possible to overshape a blank, carving down through the stiffer foam into the soft stuff. You’re a not a real heavy guy, it’s possible that happened in a board made for your weight that already wasn’t as stiff as it should have been.

Me, I’d suggest that you go for another board. And specify a heavier/ruggeder blank from the get-go… The weight difference will be minor, the durability difference will be considerable. 

hope that’s of use

doc…

Stiletto booties lol! Thanks all for the feedback. Seems as though it may be more likely its a blank issue than a curing issue. As far as I know, initial glassing happened 9 days before the session, it’s fall, so the board could’ve certainly sat in lower temps in a shaping shed. In my posession, it sat in my living room for two days before the first session. Living room smelled like resin. Board does not smell anymore. I get that stringer color had nothing to do with the integrity of the blank, was just thinking it could maybe (but most likely not) identity the supplier. It’s possible it could’ve been shaped too far into the core of the blank -  would an experienced shaper do that? My plan is to take it out, see if it keeps happening. If so, do you think I’m out of place requesting a replacement? The shaper is a nice dude, pretty much did offer to replace it if it keeps denting as easily as that first session. I hate burdening a small company that I want to support though over a mostly cosmetic issue.

Stiletto booties, yeah. You just haven’t met the right girl yet. They’re out there, in every sense of the phrase. 

In any event. Let it sit someplace warm to cure for a while longer, see if the problem persists. I’ve seen really soft glass before, but that was way back when, Nat Young’s own personal Weber factory rider boards that were squeegeed too much, maybe, and didn’t have a hotcoat or gloss on the deck at all, meant to last a week to a month. 

Stringer color- yeah, it’s kinda generic, blank builder A will have mahogany and balsa and basswood, as will B and so on. 

It’s entirely possible that somebody overshaped a blank. Also possible that somebody else poured a little less foam mix into the mold than they should have, and it’s a little less rugged than it ought to be. It happens, surfer labor, they fuc# up now and then. 

But chances are it’s not your shaper’s fault. If the problem continues and it’s the foam, well, yeah, he’s supposed to know more about blanks than you do, maybe he could have seen it, maybe not. If he offers to replace it and you don’t want to hurt his bottom line, offer to split half the cost with him, costs of a heavier blank and glassing and fins, he won’t be out for more than his time beyond that  and everybody comes out okay, and you hang on to Ol’ Softie for any guests, beginners or other annoyances who want to borrow yours. 

hope that’s of use

doc…

It happens more than you might think. If the shaper didn’t have a close tolerance blank in stock that was the ‘perfect’ size for what you ordered he may have used a larger blank than what would normally be chosen. That can lead to over-shaping, in a sense. The rocker in the blank can affect it, too. If the rocker’s not a good match for the finished shape he may have taken more off the top than the bottom.

As far as stringer color goes, wood can vary a lot in color, depending on the species. Stuff like poplar can be off white, all the way to black, in the same piece of 1x4. Other types vary less, but it’s still not unusual to see two strips from the same rough piece that are like night and day. Also, the more common woods used in stringers are basswood and spruce. Do you happen to know what yours has? 

You didn’t get what you paid for.  Most likely not as specified.  The glass shop skipped on you.  The three main Poly blank manufacturers these days don’t make close tolerance blanks that can be overshaped. Cell structure is consistent and anyone who has shaping experience within the last ten years would know that.  Taking more off of one side than the other hasn’t got a damned thing to do with it.  You got a “one drop” fake Volan glass job…  Probably Chinee-com glass too.

And may be there is something wrong with resin that let it on the softy side because with as much fiber/resin fully cured you may not have full of dent but a larger deepless foot well. You can take the stiffer carbon fiber, lam with soft resin ended in flexy skin.

Stiffer is a skin less dented is foam even softer one. That’s way carbon airex windsurf skin don’t dent even on 0.75 eps.

Some glass shops don’t even keep a roll of Volan in the rack.  They just do a “one drop tint” in six ounce.  Laminators who don’t normally work with Volan hate it.  Doesn’t saturate easily, hard to wrap and is heavy when saturated so droops on the lapped rail.  Your board might not have been aged a few days.  If you let Volan cure a few days it is usually pretty rock hard.  I can’t imagine a 150 lb. guy heel denting Volan the first time out.  Most of the Volan used these days is six ounce not ten like the old days.  Not counting the deck patch;  How many layers of what on the deck to equal 16??

Not curing long enough was my first guess.    

Not that you’d want to do this to a new board, but couldn’t you try the hair dryer trick to maybe warm up and pop those dents back out? I think it was McDing that suggested this technique (although, not in this thread).

 

Thanks for all the replies. I won’t be able to ride it for another week at least due to lack of waves so I think only time will tell. If there’s no more unexpected dents next time I surf, it was most likely cure time. If there is, the blank is most likely to blame.

@monkstar1 I’ve read about this hair dryer technique, and I’ve pondered it, but I’ve also seen some warn against it as it could lead to delam or further damage. Heat is generally an enemy. I know with the technique you apply localized and indirect heat while rapidly waving the heat gun or hair dryer over the spot, but it seems a little sketchy…

Has anyone ever had success with this technique other than taking small dents out of shaped foam before glassing?

Never tried to use a heat gun on a glassed board and don’t know that it would work.  I have used heat guns and blow driers to raise dents in unglassed blanks.  The technique consists of making a pass or two over the dent with a heat gun.  A blow dryer is better because it doesn’t get as hot.  The other trick is the old woodworker trick of applying a folded damp cloth on the dent and then running a household iron over it.  The heat and steam raises the dent.  The problem with the heat gun is that if you hit it too much the foam will burn or turn brown like toast.  So be careful.  This is the reason I like to keep an old “Goodwill” blow dryer around the shop.  Doesn’t get as hot.  You’ve got me thinking.  I may try this on a glassed board.  I would think if you were careful, it might work.  These little tricks with the blow dryer and iron, don’t work on EPS.  

Yeah I think you just need to let it cure a week.  There is one brand out of the big three that is softer than the other two;  I won’t name it on a public forum, even though I think I have done so in the past.  Do your research…  Hint;  Who has the closest conection historically to Soft Clark Foam?

It’s been many years since I’ved used PE, but I’ve been told before that the obvious VOC smell means the resin is still simmering and hasn’t reached it’s “full-as-it-gets” hardness.   Like the others have said, if the shaper took a bunch of thickness off the deck instead of the bottom then the core might be sensitive to pressures.  

I haven’t made a PU/PE board for years, but I remember seeing a 2 week wait for poly resin.

9 days from shaping to riding doesn’t leave much time from when the board is finished being glassed till you used it.

As a comparison, I’ve made 2lb EPS core with 3 layers of glass on the deck, and after the first surf, I’ve had dents.

That’s the nice thing about UV.  Ride it th same day you make it.  I have shaped a lot of Arctic and Millennium in recent years.  A few US Blanks as well.  While there are differences in all three foams and the way they shape;  cell structure throughout these blanks is consistent.  The old “don’t take too much off the deck” problem is a thing of the past and primarily a Clark Foam issue.  Some of the lighter formulas do dent.  The lighter the foam, the weaker the cell structure.  Millennium’s red is their lightest foam(they make one lighter for Pros).  The original Red would dent pretty easily.  But a couple of years ago they reformulated the red foam and now it is great.  They describe the newer Red foam as less crushable.  Most of the Shortboard blanks In Millennium Foam I sell are Red.  One shaper buys Red longboard blanks for a “Comp” model longboard he shapes.  Artic’s Yellow and Orange are also very good lightweight foams.  But typically;  If you go to a lighter foam blank it is more likely to dent.

As Lowel says, try an iron and a damp cloth, the temp won’'t get over 212°F/100°C, If it does anything, great, if it doesn’t, no harm-no foul. I have done that in the past, mixed results. Sometimes it worked, sometimes it didn’t.

As you say, it’s kinda sketchy applying a lot of heat and if you have a delam starting under those dents, crushed foam, well, it won’t be just starting any more. Better to have the dents. Throw some deck pads on it, call it a day.

hope that’s of use

doc…