Recommended repair method of gelcoat nicks and gouges?

[Hyperacme]

I thought it was so it would cure.
It also gives it a smooth surface, so no sanding needed.
Instruction said to do it, so I did.

MATCH N'PATCH REPAIR KIT
http://www.evercoat.com/product-detail/part-number/100668/us/

[Neutron68]

This morning I started grinding out the loose bits of gel coat and smoothing the edges of the nicks.

When I got down to nice solid surfaces, I was into the fiberglass layer to the point where I think I need to do figerglass repair to most of these.  So, gel coat repair isn't going to occur this weekend...

On Friday I bought this kit:
https://www.westmarine.com/buy/west-system--105-k-fiberglass-boat-repair-kit--12954095?recordNum=1

Their how-to video shows using faring compound to fill in the shape.
https://www.youtube.com/watch?v=W7M-mxAgAgI

The way it looks, they built up the surface to flush with the existing gel coat?!  Doesn't that seem wrong?
I would think you'd want the fiberglass and resin layer to be lower than the original gel coat, so when you put a gel coat layer over the top, it will be flush with the original gel coat.

Are the brushes going to be cleanable and reusable? 
If so what cleans the resin out of the brushes?
If not, I'd better buy a bunch of brushes!

Eric

[Hyperacme]

Is that epoxy resin repair kit ?
Once resin kicks ... there no cleaning.

[Neutron68]

Is that epoxy resin repair kit ?
Once resin kicks ... there no cleaning.

Yes, it says 105 epoxy resin...uh oh.  I bought the wrong stuff, didn't I?

I wanted a polyesther resin fiberglass repair kit and I thought that's what I bought.

I think this repair project just ground to a halt!

[Neutron68]

I can't believe I keep getting the wrong resin!!

Is the 3M / Bondo brand ok to use on boats with polyesther resin & fiberglass?

It says polyesther resin...."Non-shrinking polyester resin bonds to metals and plastics"
https://www.amazon.com/3M-Fiberglass-Resin-Repair-Pint/dp/B000BO9NOO

I just want to be sure!

[Hyperacme]

Years ago, I redid an old Tri-Hull and used this stuff to repair chip in hull bottom.
http://www.acehardware.com/product/index.jsp?productId=1394247

Color of boat was off white, matched OK ...

I would call or stop by Express Composites and talk with them.
http://www.expresscomposites.com/

Most of this stuff has a "Shelf life" and could have sat around for years.
Plus ... after using some of the Bondo/3M products, there mixing instruction are three drops of hardener to one spoon full of product.
Express has mixing cup and syringes to get exact amounts, makes thing a lot easier and you get consistence kick times.

[thedeuceman]

For the gel coat repair, I've seen some videos where they put a layer of clear plastic or waxed paper over the curing gel coat, and at least 1 where they didn't put anything over the curing gel coat. 

Is the clear plastic or waxed paper there for curing or for keeping it from dripping or running?

Eric

It does help prevent sagging but main reason is so the surface will cure. On big jobs you add a wax "surfacing agent" that forms a skin to protect it during curing.


Sent from my iPhone using Tapatalk

[Neutron68]

I looked at the open hours of Express Composite.  They are only open 8am-5pm M-F. 
I work those same hours so, I won't be able to go there when they are open.

I see that Home Depot carries the 3M Bondo fiberglass chemicals! 
So, if the 3M Bondo products are compatible with fiberglass boat repairs, that looks like a pretty easy-to-buy option.
http://www.homedepot.com/p/3M-Bondo-1-qt-All-Purpose-Fiberglass-Resin-20122/202077790

[Hyperacme]

Why do you need resin ?

"You are going to need to get some gel mixed to match. Tape off the area and sand the spot to repair. then apply the new gel then sand and buff entire area to blend in the repair."

[Neutron68]

Why do you need resin ?

Sunday morning I started grinding out the loose bits of gel coat and smoothing the edges of the nicks.  Some of the fiberglass resin was a bit flakey, too.  It's been exposed for the whole time I've had it (4 summers).
When I got down to a nice solid surfaces, I was a little into the fiberglass resin layer to the point where I think I need to do maybe 1 layer of fiberglass repair to most of these spots.

[Hyperacme]

OK ...

[Neutron68]

Jeeze the West Marine guy kept trying to talk me into the epoxy resin! 
He said, oh yes you can gel coat over it. 
You just have to wait 15 days for it to cure before you apply the gel coat.
15 DAYS?  THAT'S the best spin you can put on epoxy resin??  NO THANKS!

He said HE'D never use polyester resin for a repair, because it absorbs water and it would bubble up.
Given that my 39 year old boat isn't all bubbled up and soaked with water, I don't believe him.

Menards carries the 3M fiberglass resin, too.  I've never known 3M to have bad products.  I'm betting it's good.
https://www.menards.com/main/tools-hardware/automotive-marine-hardware/automotive-tools-shop-equipment/bondo-reg-fiberglass-repair-kit/p-1444421745980.htm

[Hyperacme]

"Menards carries the 3M fiberglass resin, too.  I've never known 3M to have *Censored* products.  I'm betting it's good."

From "Bondo® Fiberglass Resin"  DIRECTIONS FOR USE:
http://bondo.com/bondo-fiberglass-resin-401.html

"Mix resin as follows: Estimate amount of resin needed to completely saturate mat or cloth; Pour resin into clean container. DO NOT use waxed cup. Correct amount of liquid hardener is supplied with each can of Fiberglass Resin. For ¼ can of resin, use ¼ tube of hardener. When mixing small amounts use 8 to 10 drops of hardener per ounce of resin or ¼ teaspoon of hardener for 6 tablespoons of resin. Note: use push pin or thumbtack to open the hardener tube working life of mixed resin is approximately 8 to 12 minutes. Mix in small amounts; never mix hardener with entire resin can.

" 8 to 10 drops of hardener per ounce of resin" 
Good luck getting the right amount, not enough and it won't kick ... To much and it will melt the mixing cup ...

[Hyperacme]

Express composites chart

You get the exact amount and kick time ... every time.

[Neutron68]

The directions for the 3M Bondo fiberglass resin look like all the other mixing directions I've seen - some number of drops of catalyst per ounce of resin.
example: http://newcontent.westmarine.com/content/documents/pdfs/OwnersManuals/MAINTENANCE/14153274-FIBERGLASS%20REPAIR%20KIT%20INSTRUCTIONS.docx

Does Express Composites have pre-assembled fiberglass repair kits, or do you have to piece together your own kit from individual chemicals and pieces? 

Any ballpark idea of cost for the small amount of materials needed to make up a repair kit?

How do you buy from Express Composites?
From my point of view, they are never open, when I'm able to shop.

[fireman24mn]

Do you have some pics of the nicks and gouges now that they are ground out. Unless they are really bad you should just be able to fill them with gel. Gel is pretty much just resin with pigment added.

The pics posted above wouldn't lead me to believe you need any glass repair.

[Neutron68]

Do you have some pics of the nicks and gouges now that they are ground out. Unless they are really bad you should just be able to fill them with gel. Gel is pretty much just resin with pigment added.

The pics posted above wouldn't lead me to believe you need any glass repair.

No, I didn't shoot any photos after grinding out the loose bits.

That long worn-away area on the lower hull fin probably has 1/4 inch of material shaved off, compared with the undamaged sections in front and behind it.
Wouldn't it be good to put back a few layers of narrow glass mat strips to build it back up before gel coating?

[fireman24mn]

How large are the areas you ground out? With out seeing it its hard to say but if you put 2 layers of glass and some resin I am guessing the area will be completely filled, with no room left for gel.

Call Express and ask them if you could cut a small piece of glass mat and wet it out with the gel.  Then you would start getting the color build you need with out creating a large repair area (not sure if you can do this). If you really think you need to add glass back into the area.

If it doesn't have large cracks and isn't all the way threw I would think you would be fine without adding glass back in.

[Neutron68]

How large are the areas you ground out? With out seeing it its hard to say but if you put 2 layers of glass and some resin I am guessing the area will be completely filled, with no room left for gel.

Mmmmm, with the beveling of the edges, I suppose most of the gel coat chips grew about 1/8 inch in radius, so a 1 inch wide gel coat chip is now 1 1/4 inches across.

As far as added depth...the worst chip is probably 1/16 inch deeper?  1 layer of glass cloth deeper?

[fireman24mn]

I still think you could probably just fill them with gel. Talk to one of the guys at Express Composites they will be able to tell you for sure how deep of gouge you can fill.