Author Topic: How to fix delamination bubble?  (Read 7051 times)

puget sound

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How to fix delamination bubble?
« on: July 15, 2020, 09:47:04 AM »
I've got a delam bubble to fix on my SIC RS. Long story, totally my fault...

In April, I found my SIC handle was leaking. I removed some deck pad and found a small crack at the edge of the handle. Sanded down to good material, and fixed with some 6oz fiberglass. I paddled it like this all spring with the deck pad missing around the handle. No problems.

I finally got a roll of replacement deck pad this week. I left my board in the sun for an hour, thinking it would soften the existing deck pad adhesive so that I could scrape some more off and make the replacement pad fit. You guessed it...I found a big bubble of delamination when I came back, just behind where my heels would go. It's about 7" in diameter.

So...how to fix a bubble like this? If it's a matter of cutting out bad material, sanding, and laying some new fiberglass (or carbon cloth?), I can do probably do a decent job and get back on the water. If it requires a vacuum bag setup or other fanciness, I'll need to find a pro.

I'd actually be happy to hire a pro for this one, but my fav shop is a couple hours away and booked out over a month for repairs.
Starboard Sprint 21.5 / SIC RS 14x23 / SIC Bullet V1

TallDude

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Re: How to fix delamination bubble?
« Reply #1 on: July 15, 2020, 10:18:59 AM »
Going to have to cut that area out, sand it level, then patch. It isn't going to go down. It doesn't have to be CF. I'd probably use three layers of 6oz E glass. You can do it!
« Last Edit: July 15, 2020, 10:21:48 AM by TallDude »
It's not overhead to me!
8'8" L-41 ST and a whole pile of boards I rarely use.

surfcowboy

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Re: How to fix delamination bubble?
« Reply #2 on: July 15, 2020, 07:57:44 PM »
Yeah I agree, you can cut it and lay in. Few layers of glass.

If it’s carbon you can still hand lay it though E glass will do fine for a small area  sand it, paint it to match or put the pad back over it and go!

PonoBill

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Re: How to fix delamination bubble?
« Reply #3 on: July 15, 2020, 09:43:11 PM »
I agree with what Tall and Cowperson are saying except E-glass. I've used my last piece of e-glass. Is it the price guys? fiberglass is cheap, and S is better in every way. And since I've got lots of carbon kicking around I'd do one layer of carbon, one of S-glass. Whatever you do for the first layer, paint the area with epoxy first and scrape it so you shove epoxy into the surface. Then I'd prewet the carbon on the table, set the patch on and roll the shit out of it with a bubble roller to get it well incorporated. Lay on one or two layers of prewet glass, let it kick. Sand very lightly and put your deck pad on.

Also, instead of "cutting" I'd sand the bubble away until all the delammed glass is gone. It's easy to extend the delamination with any kind of prying force. You don't want that to happen. And sanding until you get to solid lam will give a nice feathered edge if you're careful.

It probably wasn't just the sun that did the damage, you probably had some water in there.
« Last Edit: July 15, 2020, 09:49:13 PM by PonoBill »
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

TallDude

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Re: How to fix delamination bubble?
« Reply #4 on: July 15, 2020, 10:07:19 PM »
If you have some CF laying around then use it. It sounded like you haven't done your own repairs, so you may not have extra supplies laying around. Being it's in the standing area, CF would be the best for the repair. If your supply store only has a heavy 12oz boat glass repair kit, that will work.
It's not overhead to me!
8'8" L-41 ST and a whole pile of boards I rarely use.

puget sound

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Re: How to fix delamination bubble?
« Reply #5 on: July 16, 2020, 06:44:28 AM »
I've patched a few small dings, nothing major. I have epoxy and some fiberglass cloth from West Marine that doesn't say S or E...just "Fiberglass Cloth, Medium density, 6oz." Happy to buy CF if it will make a difference. Durability is my biggest concern.

Googling "bubble roller" was good for a laugh.

I dremelled carefully around the delam bubble and the piece that lifted off is CF backed by a thin pink layer of what looks like high density foam (3/16"). The SIC website describes a PVC deck reinforcement. Maybe this? Beneath that is some white cloth on top of the EPS foam. The cloth was moist when I first removed the deck material...presumably from the leaking handle months ago. More prep work needed, but here's a photo of this stage.

Would you epoxy CF or fiberglass directly onto the white cloth or does the PVC/foam material need to be replaced? I thought about cutting a thin piece of plywood to fit and glassing over that.
Starboard Sprint 21.5 / SIC RS 14x23 / SIC Bullet V1

PonoBill

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Re: How to fix delamination bubble?
« Reply #6 on: July 16, 2020, 07:48:12 AM »
Yes, it's sandwich construction for the deck which means a layer of glass, a layer of PVC or other material, and then another layer of composite. Given the small area and the fact that you probably don't stand there you can perhaps get away with fudging, but don't go too far. Plywood is very stiff compared to PVC and will create a stress point if you do step on it which can crack the edges of the repair. You're going to have to either spend a bit of money on supplies or go to a pro, and this won't be a cheap repair. A pro would use the same materials that were originally there. If you're going to do the repair yourself you could do the same. I'd guess you're looking at $200-300 for pro work, so you could spend the same amount of materials and still be ahead because your don't have to wait, drive 200 miles, and you'll learn a useful skill.

But if you want to use what you've got, which is certainly e-glass, then at least get some PVC to replace what's gone. You can get 1/4 sheets of divinycell at https://shop.fiberglasssupply.com/Core_Materials-Divinycell_Foam_Core.html for about 30 bucks, but you can call them and ask about off-cuts for a lot less. The biggest cost will be shipping, so if you get a size that they can slip into a FedEx envelope you're gold. Just make sure you get the right thickness. Stick it down to the existing base glass with epoxy.

I would exactly duplicate the existing construction. There's probably a sanding layer of glass on top of the carbon that you aren't seeing. My work looks super sloppy because I never bother with cosmetics, but I do pay attention to stress and original strength. You've got a very nice board. Keep it that way.

The water is what causes the delam--not your fault. But make sure everything is super dry. You can get small chunks of carbon on eBay for less than 20 bucks for more than you need.
« Last Edit: July 16, 2020, 08:21:52 AM by PonoBill »
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

jrandy

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Re: How to fix delamination bubble?
« Reply #7 on: July 17, 2020, 05:34:37 AM »
I have an old windsurfer that I went after a couple bad spots and before I was done I was dug into the HD foam and EPS layers. I got a little bummed and it's been 'drying' for 2-3 years...

If you are not familiar, the Board Lady website (Eva-M. Hollmann) below is an awesome overview of all things related to board repair. Many pages of info, here is one to start.

https://boardlady.com/anatomy.htm

There are also videos online from NelsonFactory that show new construction, they kinda help me get into a 'headspace' for multilayer composites.

http://pushheretosavealife.com/
Be safe, have fun. -J

surfcowboy

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Re: How to fix delamination bubble?
« Reply #8 on: July 17, 2020, 07:25:10 AM »
I agree with Pono. (I can’t usually get 6oz S easily and I weigh 140 so I don’t bother.)

Yes to PVC, yes to carbon, a yard is cheap, and yes to learning to do this. I did an old longboard 6 years ago and now I have a rack full of various boards that work (and some that don’t but I know why now, which is fun.)

And Pono also called out that sanding a hole is better since you need that beveled edge to make it strong on the edge.


puget sound

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Re: How to fix delamination bubble?
« Reply #9 on: July 17, 2020, 08:27:11 AM »
Yep, I'm happy to embrace the DIY mindset. Thank you for the tips and links. A few hundred $$ is reasonable and it makes sense to match the original materials. While I don't stand in this area, I do tend to step there on my way back to the tail.

The divinycell is still delaminated around half the hole I cut. Half is attached to the foam beneath, half clearly detached...so it'll need to grow some more. Does this sound like a workable game plan?

1. Sand around the hole until all the delaminated material is gone. Sand the perimeter of the opening so that it's feathered from carbon down to foam. I'll try the random orbital sander this time instead of the dremel.

2. Cut divinycell to fit the hole. Squeegee epoxy into the foam and onto the divinycell. Marry the two together and clamp or weight on a falling thermometer.

3. Cut a piece of CF an inch bigger than the hole in every direction. Follow PB's description to paint the area with epoxy, pre-wet the CF with a bubble roller, and apply. Use something like this 5.7oz cloth from ebay?  https://tinyurl.com/y64tn468. For epoxy I have West System 105/205.

4. After CF has cured, sand lightly and do the same thing with a layer or two of fiberglass cut a bit smaller than the CF. Sand, apply deck pad, enjoy cold beverage.

How do I know the foam inside is dry this time?

Starboard Sprint 21.5 / SIC RS 14x23 / SIC Bullet V1

Bean

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Re: How to fix delamination bubble?
« Reply #10 on: July 17, 2020, 08:47:25 AM »
How do I know the foam inside is dry this time?

Tape a square of clear plastic wrap over the open area. On a rising thermometer, if there is significant moisture, condensation will appear in the wrap.

PonoBill

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Re: How to fix delamination bubble?
« Reply #11 on: July 17, 2020, 09:14:31 AM »
Sounds fine, be careful about picking away at the delam, the connection between materials in a surfboard is not as strong as you might think. The laminations resist downward pressure just fine, but if you lift up it will likely delaminate further. I made this mistake myself and wound up having to rework a far larger area than I should have. That's one more reason to prefer sanding away the layers rather than cutting away. The skilled pros can whack away at this stuff and make it look easy, but we amateurs need to be more careful.

The best way I've found to be sure the area is dry is to tape down plastic over the open area and set it in the sun for a few minutes, then shade. If the plastic shows condensation you still have water. Get it totally dry--the sun is your friend.

Your sanding layer needs to be a little larger than the CF, not smaller. Not a lot, 1/4 inch is fine. You're going to put deck pad over this area anyway, so don't get carried away sanding it--if at all. A little tilt to your sander and you can burn through the glass in a flash and start cutting CF fibers. And don't sand the CF or wait for the CF to cure completely to add the glass layer. If you do that you only get a mechanical bond, you want the matrix to chemically incorporate as well. I'd put the glass layer on with the CF still dead wet and roll both of them with the bubble roller. Don't gook it up with epoxy enough to get a glossy surface, if you table wet the CF and the glass it will be fully saturated. When you put it on the board it will look dry. Roll it, let it kick, and then brush on a thin layer of epoxy to fill any pinholes. You probably won't have any but a little extra insurance doesn't hurt.

The main reason for the glass is to reduce pinholes--the fine weave gets filled more consistently than the coarse CF. Each strand of CF is thousands of fibers in a loose strand, for example 3K cloth means each thread of the weave is actually three thousand fibers. It's harder the ensure each strand is fully encased in epoxy than a fine weave cloth like 4oz glass. It's called a sanding layer because that's the usual step taken to get a smooth surface for hotcoat, but you won't be doing that, and from the look of the surrounding area that wasn't done during manufacture--most boards that come with a deck pad installed are ugly under the pad.

That approach would make for an ugly repair in a glossy part of the board, which is how my repairs generally look, but this is going to be covered by deck pad. I wouldn't sand it at all.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

blackeye

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Re: How to fix delamination bubble?
« Reply #12 on: July 20, 2020, 01:13:53 PM »
Yep, I'm happy to embrace the DIY mindset. Thank you for the tips and links. A few hundred $$ is reasonable and it makes sense to match the original materials. While I don't stand in this area, I do tend to step there on my way back to the tail.

...a workable game plan?

1. Sand around the hole until all the delaminated material is gone. Sand the perimeter of the opening so that it's feathered from carbon down to foam. I'll try the random orbital sander this time instead of the dremel.

2. Cut divinycell to fit the hole. Squeegee epoxy into the foam and onto the divinycell. Marry the two together and clamp or weight on a falling thermometer.

3. Cut a piece of CF an inch bigger than the hole in every direction. Follow PB's description to paint the area with epoxy, pre-wet the CF with a bubble roller, and apply. Use something like this 5.7oz cloth from ebay?  https://tinyurl.com/y64tn468. For epoxy I have West System 105/205.

4. After CF has cured, sand lightly and do the same thing with a layer or two of fiberglass cut a bit smaller than the CF. Sand, apply deck pad, enjoy cold beverage.

Your plan sounds very much like the BoardLady fix demonstrated here: https://boardlady.com/bottombubble.htm

She went down to EPS, but it sounds like you have a sound glass layer already, so you are starting with the thin HD foam.

I would buy carbon remnants from https://www.sollercomposites.com/Remnants.html . He doesn't list any pieces right now but has a note saying to call for 3K pieces smaller than a yard.


puget sound

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Re: How to fix delamination bubble?
« Reply #13 on: July 21, 2020, 08:26:26 AM »
Clear plastic over the hole to test for moisture...brilliant.

Thanks for all the tips and links. I have some carbon fiber and PVC on the way from Soller. When they and the bubble roller arrive, I'll give it a shot and post some photos.

The BoardLady makes these repairs look...not simple, exactly, but at least straightforward.
Starboard Sprint 21.5 / SIC RS 14x23 / SIC Bullet V1

puget sound

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Re: How to fix delamination bubble?
« Reply #14 on: July 26, 2020, 05:41:55 PM »
The repair went well:  I had to sand a larger hole to get to good material, then epoxied one layer of 1/8” Divinycell and let it sit under pressure for a couple days. Good fit. Finished it with one layer of 5oz carbon topped with 6oz fiberglass, both wetted first on a table. The bubble roller turned out to be one of those magical little tools—perfectly suited for its job and nothing else. The repair won't win any beauty contests, but seems strong and watertight, and it can hide beneath the replacement deck pad.

Fun fact: X-acto knives get dulled really easily with these materials. I must have gone through 10 blades cutting fiberglass, carbon, and deck pad shapes. They're cheap.

The CF, Divinycell, and bubble roller set together were less than $100, with plenty left over for future repairs. New skill and I'm back on the water. Thanks for the help!
Starboard Sprint 21.5 / SIC RS 14x23 / SIC Bullet V1

 


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