Best value pre-made fiberglass filler alternative to making Fiberglass PB

havoc_squad

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What is the best value pre-made polyester compatible fiberglass filler product out in the market today for significant quantities used as Fiberglass PB? Or is there a proven less toxic alternative filler than cabosil that can be used?

If it is premade, preferably one that has the wax in it so I don't have to put PVA or wax on it to cure. Or does PVA spray easily wipe away with a wet rag so I don't have to worry about getting water on uncovered wood not ready for fiberglass & resin yet.

Reason for asking is that I have an upcoming fiberglass floor and very likely stringer project likely for next spring and I really do not want to mess around with Cabosil to make fiberglass PB given how highly toxic it is given how easily airborne it gets.

Yes, I plan to be using a P100 grade respirator filter particle filter with organic vapors filter for the chemicals.

I know of 3M, Evercoat, and a few others make short and long strand versions of this product, just wondering if there are cheaper options than them available via retail.
 

Scott Danforth

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Don't use wax, or you have to sand. Let it tacky for the next layer. That's why boatyard resin and layup resin do not have wax

I have used Tigerhair in the past, however one of the fillers is talc. Not good in a marine environment. FGCI has a Tigerhair like filler

All fillers with glass strands are toxic and require a respirator
 

todhunter

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Does your fear of cabosil come from experience, or just what you've read? Speaking from experience, it's not that bad if you're careful. Wear a respirator and gloves (you'll already be doing this for the vapors). I preferred mixing in my MEKP to my resin first, then adding cabosil in a few does. You can reduce how much cabosil gets airborne by changing how aggressive you stir. I would more "fold" the cabosil into the resin until it started getting absorbed, then I would start stirring. I could mix a 17 oz batch of PB and get it into a piping bag in about 5-6 minutes, which left me plenty of working time.
 
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havoc_squad

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Does your fear of cabosil come from experience, or just what you've read? Speaking from experience, it's not that bad if you're careful. Wear a respirator and gloves (you'll already be doing this for the vapors). I preferred mixing in my MEKP to my resin first, then adding cabosil in a few does. You can reduce how much cabosil gets airborne by changing how aggressive you stir. I would more "fold" the cabosil into the resin until it started getting absorbed, then I would start stirring. I could mix a 17 oz batch of PB and get it into a piping bag in about 5-6 minutes, which left me plenty of working time.

The primary concern is that powder getting on locations where it is not expected to be in dangerous amounts and becoming airborne without respirator on.

In short, incidental exposure to cabosil powder inhalation after cleanup has been safely done of the mixing area.

Just to be clear, I am aware you keep PPE on until all cleanup is properly done and bagged so you don't inhale toxic materials or fumes.

The floor is the easiest area I could see this happen in missing a spot after cleanup.

I've worked safely beforehand with proper gloves and respirator PPE small amounts of polyester resin fiberglassing, grinding, and small amounts of gel coating that I have done previously. So I'm not paranoid of working with this in general, I just don't like highly toxic powders unless it can't be avoided.

Fumes eventually dissipate, cabosil powder does not.

If it is not insanely more expensive, I would like to avoid the added risk of messing with cabosil powder by using a premade product.
 
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Scott Danforth

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its a bit pricy, however all resin is.

maybe give them a call. I do not see the tigerhair like product on their website, however it is on the shelf.

 

JASinIL2006

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I did my fiberglassing in my garage, so I mixed Cabosil into the uncatalyzed resin outside, so there was no free-floating Cabosil to worry about.

I mixed in the MEKP last, so I didn't need to worry about the mixture kicking off while I was fiddling to get the proportion of chopped strand and Cabosil to my liking.
 

huggyb1972

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What is the best value pre-made polyester compatible fiberglass filler product out in the market today for significant quantities used as Fiberglass PB? Or is there a proven less toxic alternative filler than cabosil that can be used?

If it is premade, preferably one that has the wax in it so I don't have to put PVA or wax on it to cure. Or does PVA spray easily wipe away with a wet rag so I don't have to worry about getting water on uncovered wood not ready for fiberglass & resin yet.
 

huggyb1972

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I picked up on the uncoated wood remark. You won't have nearly as good of a bond if you're not pre-coating the wood you're bonding with cabosil.

Depending on how much pb you think you'll need. You could add resin and cabosil together in a 1gallon paint can, seal it, and tumble the can until it's mixed to the consistency you'd like. I like to use a 1qt paint cup about 8oz. of resin the rest with cabosil until you get the correct thickness use a tongue depressor to mix with in a non windy/drafty environment. Work slow until you can get resin on top of the cabosil.

Your being really careful about cabsil dust, but there's going to be lots of fiberglass dust in your future.
 

havoc_squad

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I picked up on the uncoated wood remark. You won't have nearly as good of a bond if you're not pre-coating the wood you're bonding with cabosil.

Depending on how much pb you think you'll need. You could add resin and cabosil together in a 1gallon paint can, seal it, and tumble the can until it's mixed to the consistency you'd like. I like to use a 1qt paint cup about 8oz. of resin the rest with cabosil until you get the correct thickness use a tongue depressor to mix with in a non windy/drafty environment. Work slow until you can get resin on top of the cabosil.

Your being really careful about cabsil dust, but there's going to be lots of fiberglass dust in your future.

Fiberglass dust is in the boat, not in my garage. Easy to mitigate in the boat, keep the respirator on in it until it has been cleaned up and rinsed off.

As said before, not my first rodeo with fiberglassing even though it was a small internal repair section.

Bag and throw away loose trash and do not take it in the garage/house. Rinse large pieces of trash if they are caked after broken down if necessary. Clean tools to remove fiberglass dust before putting them back in garage or storage.

Once cleanup has been done, wipe your face off with goggles to keep it out of the eyes. Remove Tyvek suit and dispose of or seal in bag if re-usable. Rinse shoes off, then take mask off. Then you can go inside.

No fiberglass grinding in garage. Big no no in my house rules.
 

KJM

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Fiberglass dust is in the boat, not in my garage. Easy to mitigate in the boat, keep the respirator on in it until it has been cleaned up and rinsed off.

As said before, not my first rodeo with fiberglassing even though it was a small internal repair section.

Bag and throw away loose trash and do not take it in the garage/house. Rinse large pieces of trash if they are caked after broken down if necessary. Clean tools to remove fiberglass dust before putting them back in garage or storage.

Once cleanup has been done, wipe your face off with goggles to keep it out of the eyes. Remove Tyvek suit and dispose of or seal in bag if re-usable. Rinse shoes off, then take mask off. Then you can go inside.

No fiberglass grinding in garage. Big no no in my house rules.
Yeah, I foolishly grinded in my garage a few years ago and I'm still dealing with the dust!
 

todhunter

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Gotta build an airtight containment tent if you're gonna do it in the garage.

3-png.331585



But I digress...
How about the Total Boat Structural Repair Putty for pre-mixed?
 

froggy1150

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I'm asbestos abatement trained and what you do almost sounds worse than what we do with double gooseneck bagging and the rest. When I mixed my cabosil I just was outside away from house w/respirator and mixed careful at first
 

stresspoint

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personally i prefer to mix my own , that way i can get consistency correct for the job at hand.
some of the pre mix is too fiber heavy and i am not a fan of the hardener compound , proper hardener insures a correct mix by percentage.

sometimes its practical to use pre mix if it is required as a glue to hold something together or fixing rust holes in cars , but as a whole its not the best for marine work.
 

KJM

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I'm asbestos abatement trained and what you do almost sounds worse than what we do with double gooseneck bagging and the rest. When I mixed my cabosil I just was outside away from house w/respirator and mixed careful at first
Yeah, from what I have read, its a bit dangerous but not that bad. I think its considered a cancer causing agent in California, but everything seems to be that in California. I just mixed it carefully in my garage and stirred it in slowly. Probably not the recommended procedure but for how often you actually need to use it I figure the risk is pretty low.
 

todhunter

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I'm asbestos abatement trained and what you do almost sounds worse than what we do with double gooseneck bagging and the rest. When I mixed my cabosil I just was outside away from house w/respirator and mixed careful at first
That pic was for fiberglass grinding dust containment, not cabosil mixing. šŸ˜‚

Good luck in whatever direction you decide to go.
 
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