dumb question about resin

[Buttertoes]

Hello-I feel embarassed to ask this but I need a black and white answer from someone I trust before I start!

I bought a used fibreglass mini mal that has a couple of rail knocks. They look to me to be just in the finish but you can pick them with your fingernail. They look like lake ice when you've hit it with a rock- a white area under the surface, but they don't look like they go through the fabric.

As it happens, my dad is building a skiff which will be fibreglassed. He picked up West Systems epoxy resin 105 and hardener 206 and I wonder if I can use some to patch my board's bruises.

I found this online:
"When you read about PU boards, you are reading about polyurethane foam blanks which are the most common blanks still among both daily surfers and pros. PU foam is easily shaped and airbrushed. Polyurethane foam is known for being more responsive in its performance but it also absorbs water and yellows (over time). Polyurethane surfboard blanks can be glassed with either polyester or epoxy resin, making it versatile in terms of giving riders more options...."

So my impression is you can use either epoxy resin or polyester resin to patch a fibreglass board, but you do not use polyester on an epoxy board. Do I have this right?

Thanks!

[Buttertoes]

[kitesurfer]

I've never tried to fix a polyester board with epoxy but you definately can not fix an epoxy board with polyester.

KS

[Lebowski]

Yes you can use epoxy resin on both, but polyester resin only on PU.

[Rickyroughneck]

Yep, you are completely correct about the resins. Although to nitpick, I might point out that epoxy boards are also fibreglass

That ding is a nasty one, it is the grey area where one is not sure if it is waterproof or not. Personally I would fix it, just to be on the safe side.

You have three options:

1. Smother resin over the top to waterproof it (epoxy or polyester, doesn't matter). Easy, but if it gets hit again it will break.

2. Slap a patch over. Strongest option, but will leave a lump where you did the repair.

3. Heavy sand, then patch over the sanded area. Slightly weaker, but will be flatter.


With all repairs, feather the edges of the fibreglass patches and give it a light sand first. Sanding after is your call, but unless you have a sander and polishing compound you wont get it shiny again.

[Jimi]

Yep, as already said you can use epoxy over polyester, but NOT polyester over epoxy. There has been a lot of confusion over this in the past. There is another consideration, and that is that Epoxy is NOT UV stable, so it will discolour in the sun. a lot. It's best to just spend the $10 on a small tin of polyester and MEKP catalyst if you're planning on doing a patch. Otherwise epoxy to seal it will work o.k.

Also, Rickyroughneck has almost hit the nail on the head - however I disagree on one point regarding the strongest fix. In any fibreglass repair (epoxy or polyester) the strength of the repair depends on the quality and area of the existing material. The cracked and white-crazed section is no longer sound, and should be picked out and sanded very thoroughly to get rid of any loose/delaminated old resin/glass. Once that is all out, you should feather the edges of the repair over the good material around the edges, then cut 2 or 3 layers of fibreglass cloth to cover the foam and sanded area. Place the patches on and wet out with the resin, being careful not to use too little or too much (watch a youtube vid to see how it should look) when it's properly wetted out. Let it dry, then sand smooth. You'll end up with exactly the same strength as the board had originally, and the patch should be invisible.

If you leave all the crappy glass behind and patch over the top, it's like building on shaky foundations, and it's likely to crack again after a small impact or just the natural flexing of the board.

Up to you if you want to go to the trouble, and start digging holes in your board.

[Buttertoes]

Wow, I am really grateful for the responses everyone! They left me with a couple more questions though-

I didn't pay a lot for the board. It has a bunch of pressure dents and cosmetic finish cracks. It's a also brand I've never heard of before (is it decent or a piece of crap?? It's called Surfers Alliance or something).

Given this, would it be worth properly repairing the dings? I am willing to try and just found out that my dad is getting polyester fibreglass for the actual fibreglassing of his skiff (the epoxy was just used as glue) so I'll have access to loads of the stuff

And part B) if I cut out the ding, I'll probably be cutting out the blue pigmented material too, won't I? if properly repaired will I end up with white patches? Should I care? Is there an easy way to paint the repair to match the rest of the board?

[kitesurfer]

Given this, would it be worth properly repairing the dings?
And part B) if I cut out the ding, I'll probably be cutting out the blue pigmented material too, won't I? if properly repaired will I end up with white patches? Should I care? Is there an easy way to paint the repair to match the rest of the board?

As you will be fixing the board yourself it shouldn't cost you much and it will be good practise so yes you should fix it.
You shoiuld be able to fix that ding by picking out the broken glass carefully then using a mix of microfibres (available from most glassfibre suppliers) resin and blue resin tint. Resin tint is a liquid you casn add when mixing up the resin. It might not be a perfect match but it will be blue rather than white.

KS

[surf patrol]

Its no big deal to have white patches. My board has several and like anything you stop noticing after about 20 minutes. Of course, if you can colour match then it does look better. Its just aesthetics.

I haven't been able to find much about Surfer's Alliance. As I understand it, it was a shaping company run by a guy called Randy Rarrick in the 1980s based in Hawaii, but at some stage the name was bought out by a chain of surf shops in the US and put onto chinese made boards. I suspect you have one of the latter, which doesn't mean its bad, it is just what it is (not made by a famous shaper but perfectly useable). However, if you have one of the former (ie a Randy Rarrick made one) then its a piece of history (look here <dead link> at item no 37) .

[Buttertoes]

thanks! I will let you know how it goes

DTC, I assume if it were a Rarrick board it would be signed or something would it?

[dtc]

thanks! I will let you know how it goes

DTC, I assume if it were a Rarrick board it would be signed or something would it?

Most 'hand' (rather than factory) shapers handwrite the board dimensions in pencil somewhere on the board (usually on the bottom near the stringer). If custom built then the name of the person its built for might be there as well, but not always; and it might be a board just built to put in their shop and not have a name. Some shapers sign their boards, others dont (might just use a decal or something).

If the dimensions are machine printed then its highly unlikely to be hand shaped.

From the limited amount I could find, the later versions of Shaper Alliance boards (the machine made ones) have a really big 'surfers alliance' decal across the top front of the board; the earlier ones seemed to have a smaller decal as in that one I linked to.

But I'm no board historian. In any event, given the condition of your board, even if it was an original its probably not worth a huge amount. So you may as well just surf it and have fun.

[Buttertoes]

Cool, that's very interesting. The dimensions are hand written so I'm going to do some reading. I'm not fooling myself that I've found the arc of the covenant or anything, but would be neat to learn if it has some history. Thanks for your info

[dtc]

Some factory boards do handwrite as well, depends on how much they want to look like a handshaped board! On the other hand, I've never seen a shaper print dimensions on the board.

I gather Rarrick stopped shaping in the 1980s or 90s, so if your board doesnt look 20 years old then it might not be his; but you can never tell with boards. My longboard was made in 1994 and still goes well and looks fine.

I'm not sure how you can track down much info - Surfers Alliance seems to have been a small deal based in Hawaii. But googling intently always comes up with surprises.

http://www.swaylocks.com/forums/looking ... ing-labels

http://www.swaylocks.com/forums/surfers ... ndy-rarick

[Buttertoes]

well I just had a closer look at the board and found it- the made in china sticker! lol oh well I'm still pretty happy to have my first fibreglass board. Thanks for the info, I will have a read through the links

[Buttertoes]

Hi again!

Well I did my best but I was disappointed with the result. I thought I'd post some pictures of the process and see if anyone has a suggestion for future attempts. I am going to guess that I over-sanded it and made the cloth visible? Am I safe to leave it as is, or should I paint another layer of resin over it?

[Buttertoes]

my dog helping

[jaffa1949]

Looks like you did a good first time job, always a challenge and I hope you didn't get too much resin on the dog or dog hairs in the resin. Enjoy your summer and a "real" board under your Buttertoes.

[Buttertoes]

Thanks Jaffa The dog hair sanded out fine lol
Can't wait to try the board- hopefully this week!