Marine Grade Fiberglass?

[RonRock]

Is the fiberglass resins and associated materials really better for boats than the automotive fiberglass materials I already have on hand?

I'm working over my V25 and have some fiberglass repair work to do. First up is filling some drilled holes in the deck so that I can set a new mast hinge. The original holes are close enough to where the new ones need to be that I decided it best to fill them before drilling new holes. I started by a good cleaning, then a small disk grinding on the underside. I drilled the holes a bit larger to clean out any silicone, then beveled the holes. Then from the underside I filled with some fiberglass filler product called "Fiber Fill" it is a fiberglass resin with glass strands. Kind of like "Bondo" with fibre. I'll smooth that then glass in a couple layers of glass mat for strength. then finish up top with resin in the holes.

So this sounds like a good strong bonding fix to me. But is there a compelling reason for me to get "Marine" grade products?

The boat is in Iowa and doubtful if it will ever see any salt water.

 

[timebandit]

Pollyester (car) tends to shrink and not bond well to boat fiber glass.

Epoxie bonds well to everything (think 30 min. epoxie glue) and is more flexable.

 

[MrBill_FLL]

30 years ago all boats used polyester resin. and I use it today. vinylester, epoxy and other resins resist osmossis better that the old stuff. but epoxy doesn't like to bond back to expoy (per west system, and MAS sites). I don't see any reason to use marine grade above the waterline. but bondo I just would not use. a polyester resin mixed with tac power, or micro ballons or 'kitty hair' would be what I used. -but I do know builder using the bondo type filler and the 'red stuff' fine filler before paint. -the real question is what's the cost of cost cutting if it doesn't work... that's usually where I go get the marine grade, because its way more expensive to fix a mistake than getting the correct stuff 1st time around. .... -honest I am putting in hard carriage returns but they are being stripped out... 3rd edit...

 

[RonRock]

The Fiber Fill that I used is the same type of material as Kitty Hair, just a different brand. I also have no intention of using "Bondo" on my boat, just mentioned it as a reference to the type of filler comparable to Fiber Fill, as opposed to liquid resin. I would not use the "scratch filler" compound on a boat either.

" a polyester resin mixed with tac power, or micro ballons or 'kitty hair' would be what I used."

What is tac power, or micro ballons? Is this a type of resin with those descriptions? I've read of body filler with "Microspheres" assuming similar.


Appreciate the help guys. Being a car and motorcycle guy, it all "looks" like it should be the same.

 

[SchwarckT]

I've used automotive Bondo resin with excellent results on my boats. Its carried by www.jamestowndistributors.com and recommended by them for boat repair.

 

[MrBill_FLL]

micro balloons:

http://www.overtons.com/modperl/pro...tent_goobasecontent_filler&cID=SHOPPING_73444

are a light weight filler, same as talcum powder, they offer several types, w/ different weights. just makes sanding easier. kitty hair is just cut fibers embedded in resin. I make my own usually.


http://www.jamestowndistributors.co...&familyName=WEST+System+410+Microlight+Filler


talcum power could be used instead, its just a thickening agent.. (but not as good).

 

[RonRock]

OK, well I have done a little more reading up on resin. The Epoxy resins are pricy, but if they are what is best for the job then I guess I'll pay.

Not sure I understand your position MrBill. Are you saying that you use Poleyester (automotive) resin above water line, and Epoxy resin below water line?


"30 years ago all boats used polyester resin. and I use it today............the real question is what's the cost of cost cutting if it doesn't work... that's usually where I go get the marine grade, because its way more expensive to fix a mistake than getting the correct stuff 1st time around. ..."

 

[MrBill_FLL]

its a tough call. I would use polyester resin, anyplace you may need to re-apply resing again. above or below the waterline. (since poly sticks to poly well, and epoxy doen't stick to expoxy well. OTOH, epoxy sticks to poly very well) if I was doing a keel repair, probably polyester, since an new patch will stick to polyester resin agin. if I wanted something strong and light, like a rudder, maybe I'd use epoxy, since it stronger and lighter, but doesn't need too much volumne (cost). I would not use bondo anywere, but I've seen it used on high end marine paint jobs. (mostly the red stuff thin filler). next time around I'd use MAS epoxy. its cheaper than the west system, and IIRC, 1:1 mix. (or 1:2???) but none of those special pumps.

 

[MrBill_FLL]

sorry about the format, its some script blocker on this pc...

 

[monkeybars]

no such thing as marine grade fiberglass, glass fabric is glass fabric, and resin is resin wheather it's poly,vinyl, or epoxy.try calling one of the three major suppliers of glass fabric's and resin's they sell the same product under whatever label the retailer wants them to put on the package, and still to this day 90% of all boats are made with poly resin, some of the highend manufacter's will use a viny resin and gelcoat on the first layer to prevent blistering,the nuber of boats made with epoxy resin you can count on one hand.

 

[RonRock]

I like the thought of not using those special pumps. I was about to ask about those. Are they a one time use item? Or can you use them and let the material set with them in the can, come back 1, 2, 3, months later and still use the pump and material? They seem like a good way to waste a lot of material.

Right now I am working on upper deck penetrations. Planning on filling some that are not needed, and potting those that are. I also have a couple places in the inside ceiling that has come "un-bonded" causing a "bubble" where the mat is not bonded with the core. I plan on injecting resin into the bubble and pressing it into position. Probably not the best fix, but better than nothing. It is not near bad enough to cut the panel out and rebuild.

Edit,

Although I could cut the existing mat and clean the core section out, then glass over the work area. Would that be a better fix?

I'm trying not to get bogged down with the repairs. But I have it pretty well torn down now, so may as well do what needs to be done. I'd rather fix it now, than do more damage by not doing the needed repairs.

 

[MrBill_FLL]

what I did on the westsystem pumps was left them on, and they still worked up to a year later. (storage is a bit of a problem since the pumps are on).

the problem I had was w/ hardner. changing types and size containers. I think the very slow (for hot hot weather) was a different mix than the regular I use in winter).

and the size container, when I started I use qt's of hardner, then when to pints, so the pump was too tall. -I ended up buying new pumps. (forget the price but seem $$$ at the time).

not sure about injecting.. you can try, and let us know...

But are you trying to fix something that is not a real problem? I have lots of mat under the seats that didn't kick off properly. I ground some of it off, the rest I painted.

 

[RonRock]

You may be right about my issue not really being a problem. I may try and find a way to inject some resin into it. Not sure where to even look for an injector tool, but if I can figure out how to get something in I will. Otherwise I may just move on.

I have a tendency to let things snowball. I was waiting for the hinged mast base to get here. And with nothing to do, things come apart. And on, and on.

 

[MrBill_FLL]

I don't have a hinged base... thought about changing when I got the boat, but what I had worked... and went sailing, never looked back. West system does sell caulking guns for expoxy, like everything they sell $$$$$ a turkey baster might work too.... once.

 

[Timo42]

The West pumps are cheap, reusable and easy. The only thing I found was that the hardener tends to discolor after a time, doesn't affect the final result. The pump set I got came with tubes to fit different size cans. The West site has a lot of info on it.

 

[Robert M.]

30 years ago all boats used polyester resin. and I use it today. vinylester, epoxy and other resins resist osmossis better that the old stuff. but epoxy doesn't like to bond back to expoy (per west system, and MAS sites). I don't see any reason to use marine grade above the waterline. but bondo I just would not use. a polyester resin mixed with tac power, or micro ballons or 'kitty hair' would be what I used. -but I do know builder using the bondo type filler and the 'red stuff' fine filler before paint. -the real question is what's the cost of cost cutting if it doesn't work... that's usually where I go get the marine grade, because its way more expensive to fix a mistake than getting the correct stuff 1st time around. .... -honest I am putting in hard carriage returns but they are being stripped out... 3rd edit...

Kindly reply with the links to the WEST System and MAS web sites where it's disclosed that epoxy resin does not bond well to cured epoxy resin. I'm familiar with the WEST site but could not find the information you mentioned.

Thank you, Robert M.

 

[timebandit]

What is amine blush?

When using a solvent free epoxy resin such as Interlux Epiglass® Epoxy Resin HT9000, there are some factors you should consider before overcoating with a primer. After application and during the curing (drying) process, the epoxy releases a blush to the surface called ‘Amine Blush’. This blush is known to appear as a ‘wax-like’ film that sits on the surface of the cured epoxy resin. This amine blush will in fact keep some subsequent products applied from fully curing, performing correctly and also yellowing unless removed properly. The visibility of the blush will be determined by the moisture in the air during the curing process, however will still be on the surface if not always visible. The best way to reduce blushing is to work in warm temperatures (the epoxy sets up fast, reducing the blush window) and with humidity at low levels. It would be best to avoid conditions where moisture is coming out of the air as temperatures fall.


How to remove it?

Interlux recommends thoroughly washing the cured epoxy with clean warm water, all-purpose soap, and a stiff brush or Scotch-Brite™ pad. The amine blush is water soluble therefore the only way to completely remove this is by following the instructions above. You will want to clean the amine blush off of the epoxy before sanding as well. If you begin to sand before removing the amine blush, you may sand the blush deeper into the surface making it much harder to remove. It is a safe practice to clean all types of epoxy resin, even if the label states that it is ‘amine blush free’ or ‘no blush formula’. Please note: Aggressive solvents like Acetone will not remove the blush.

 

[Bob McL]

I am not sure of the previously stated information, but the MAS site is: http://masepoxies.com/

 

[centerline]

no such thing as marine grade fiberglass, glass fabric is glass fabric, and resin is resin wheather it's poly,vinyl, or epoxy.try calling one of the three major suppliers of glass fabric's and resin's they sell the same product under whatever label the retailer wants them to put on the package, and still to this day 90% of all boats are made with poly resin, some of the highend manufacter's will use a viny resin and gelcoat on the first layer to prevent blistering,the nuber of boats made with epoxy resin you can count on one hand.

I wont disagree with monkeybars post, but I would like to add that there are different quality's of resin being sold.... regardless of what type of resin that it is, some off brand manufactures will try to make a cheaper product by adding fillers to it.... its usually the higher quality stuff that is labled as marine grade....
but as long as you stick with a high end manufacture, you will have no problems with the quality... and I am not a proponent of spending money needlessly, or buying from a particular retail outlet, but there are some places that may cost slightly more, but you can be assured that you will get the quality you need for the job.... and doing it right the first time is way cheaper anyway....

as far as bondo goes... it works extremely well for its intended purpose. its the decision of the person using it that causes it to get a bad rep....
when using it with polyester, just mix a bit of resin to it after you get the hardener blended into it, and its easier to work with, it cures harder and sticks better.... but its a bit more difficult to sand and finish. i
and glazing putty as a sanding scratch filler works great too.... just make sure the scratch is clean and free of sanding dust....

its not usually the product thats the problem, but the technique used to install it...

 

[monkeybars]

most failures with adhesives-resins are due to contamination of surfaces, cleanliness cleanliness and clean it once more.