Results 1 to 26 of 26

Thread: Cabosil alternative? Uses for cotton flock?

  1. #1

    Default Cabosil alternative? Uses for cotton flock?

    Are there any alternatives to cabosil-type products that are "less nasty"?

    I've tried using cotton flock. I might not have mixed it properly, but the result was a little lumpy. It didn't, however sag. Is this the correct use for cotton flock. Also, can epoxy-impregnated cotton be used below the waterline?


    Your help is appreciated.

  2. #2
    Join Date
    May 2002
    Location
    Orland, Maine
    Posts
    507

    Default Re: Cabosil alternative? Uses for cotton flock?

    Reardon,
    The products I am familiar with are from West System.
    Their 406 is colloidal silica and what I believe is the cabosil product equivalent.
    Used primaraly as a thickener and is very light and 'fluffy', easily airborne.
    Their 403 microfibers is what I believe the equivalent of cotton fibers.
    Used also as a thickener and also as a gap filler for laminating. Much less likely to become airborne in my experience.
    You need to avoid breathing BOTH products,both 'nasty' stuff but the 406 is more of a problem.
    And yes, according to West, 403 is used everywhere including underwater.
    Hope this helps.
    What'cha making?

  3. #3
    Join Date
    Apr 2006
    Location
    sussex county delaware
    Posts
    2,776

    Default Re: Cabosil alternative? Uses for cotton flock?

    I've been using MAS wood flour and cellulose powder with good results so far. Cabosil supposedly gives better abrasion resistance, but is a silica product and will be bad for you inhaled. Not that the others are all that great...
    Brute force and ignorance, all in one bulky and unappealing package

  4. #4
    Join Date
    Oct 2009
    Location
    South Puget Sound/summer Eastern carib./winter
    Posts
    9,195

    Default Re: Cabosil alternative? Uses for cotton flock?

    I use 403 ,micro fibers for 99% of all the stuff I've built.

  5. #5
    Join Date
    Aug 2001
    Location
    pittsfield nh usa
    Posts
    1,880

    Default Re: Cabosil alternative? Uses for cotton flock?

    wood flour or EZ thick (paper dust) - both run about $4 a quart. You can use microspheres - (they come in different sizes/densities) - but they act like mini ball bearings - folks often combine the microspheres with the fumed silica/wood flour etc. Microspheres run $4-$5 a quart. For strength add micro fibers - same sort of prices

  6. #6
    Join Date
    Dec 2003
    Location
    Portland, Oregon
    Posts
    18,401

    Default Re: Cabosil alternative? Uses for cotton flock?

    IIRC, the wood flour is not quite as strong as the fumed silica - but don't quote me. I use wood flour for most of my (non-fairing) thickening tasks. I've yet to find it wanting.
    David G
    Harbor Woodworks
    http://www.harborwoodworking.com/boat.html

    "It was a Sunday morning and Goddard gave thanks that there were still places where one could worship in temples not made by human hands." -- L. F. Herreshoff (The Compleat Cruiser)

  7. #7
    Join Date
    Oct 2009
    Location
    South Puget Sound/summer Eastern carib./winter
    Posts
    9,195

    Default Re: Cabosil alternative? Uses for cotton flock?

    Remember, I'm the guy that does not tape his filets. It's because I use 403, not wood flour, spheres,balloons, moon dust or talc. I put more abuse in a 100 mile day on wizbang than a rowboat will see in a lifetime.

  8. #8
    Join Date
    Mar 2010
    Posts
    1,040

    Default Re: Cabosil alternative? Uses for cotton flock?

    I just used red cedar wood flour for cold molding, was pleased with the results and didn't breathe in any toxic dust. The only problem with it is that it continues to soak up the resin for a while, getting thicker as I use it. The trick was to first seal the substrate with epoxy, use as little of the dust (which I made with a performax, but the random orbit sander works well too, just slower) as possible and mix small batches. I think the sealing of the substrate was important since it helped ensure that after the flour had soaked up all of the resin it wanted there was still plenty left to soak into the new layer of veneer.

  9. #9
    Join Date
    Feb 2002
    Location
    Duncan, Vancouver Island
    Posts
    24,901

    Default Re: Cabosil alternative? Uses for cotton flock?

    I just used red cedar wood flour for cold molding, was pleased with the results and didn't breathe in any toxic dust
    I wouldn't be surprised if red cedar dust is more harmful to inhale than fumed silica. I've been known to use both.

  10. #10
    Join Date
    Oct 2000
    Location
    Wellesley, MA USA
    Posts
    8,835

    Default Re: Cabosil alternative? Uses for cotton flock?

    I see no reason to use anything other than Colloidal silica as a viscosity/thixotropy additive for epoxy. The MSDS's for colloidal silica indicate no particular safety issue.
    The only place where care is needed is in measuring and mixing it. Don't open the tub in a windy location and stir slowly and there's no problem.

    Like other epoxy additives, the prices on small quantities are insane. A 5 gallon tub is $40 from Merton's.

  11. #11
    Join Date
    Mar 2010
    Posts
    1,040

    Default Re: Cabosil alternative? Uses for cotton flock?

    It makes me stuffy, but it doesn't burn like some other things. I always step outside to mix the stuff, trying to take advantage of any breeze. Hard to avoid when sanding though. I hate wearing a mask, try to use fans and open windows and doors. My wife is allergic to cedar, which is why I have a shower in the shop, hate to think of myself as toxic to her.

  12. #12
    Join Date
    Nov 2008
    Location
    West coast Sweden
    Posts
    2,401

    Default Re: Cabosil alternative? Uses for cotton flock?

    I've been using wheat flour lately, as per Hannu Vartiala's advice. It's awkward when mixed very thin or thick. Lumpy when thin, crumbly when thick, maybe it has something to do with the gluten. So for my next project I'd be looking into something else.
    1947 Nordic Folkboat "Nina"

  13. #13
    Join Date
    Apr 2000
    Location
    Southampton Ont. Canada
    Posts
    5,702

    Default Re: Cabosil alternative? Uses for cotton flock?

    We always add fillers using a flour sifter.
    There are no lumps and it's easier to add small amounts evenly across the batch.
    R
    "Now Ron,don't you do anything stupid!" - Grandma B.

  14. #14
    Join Date
    Dec 2000
    Location
    Nelson, B.C. Canada
    Posts
    2,023

    Default Re: Cabosil alternative? Uses for cotton flock?

    Try plastic mini-fibers if you are looking for superior anti-sag and adhesive properties. If you buy it in 10 lb bags, you will save mucho $.

  15. #15
    Join Date
    Jan 2005
    Location
    Bel Air, Md
    Posts
    3,598

    Default Re: Cabosil alternative? Uses for cotton flock?

    here is everything you could want to know about cab-o-sil.http://www.eagerplastics.com/cab.htm

  16. #16
    Join Date
    Aug 2001
    Location
    pittsfield nh usa
    Posts
    1,880

    Default Re: Cabosil alternative? Uses for cotton flock?

    reason not to use fumed silica (aerosil or cabolsil brands) is that it is a real pain to mix in, but adds essentially no weight. Other fillers much easier to mix but weigh about 4x more.

    also note there are many kinds of fumed silica. Some major companies sell the cheaper fumed silica that will dissolve in water (try mixing some with water!).

    Fly fisherman pay about $10 per tiny bottle for the hydrophobic fumed silica (which is also the best to use as an epoxy thickener). Of course boat owners get it at a discount - $4-$5 a quart). Dipping their flies into the silica makes them 'wiggle' on the water surface like real bugs. I talk to these guys almost every day. My brother was pres of his local fly fishing club, too bad I didn't know out the fumed silicas when he was alive.

  17. #17
    Join Date
    Nov 2008
    Location
    The headwaters of the Petaluma River and up a hill. ,CA
    Posts
    3,531

    Default Re: Cabosil alternative? Uses for cotton flock?

    I use good old flour. The stuff one would make bread with. It conforms to all the things I would expect a filler to do. Just don't eat it.
    ..don't judge a man till you've walked a mile in his shoes..

  18. #18
    Join Date
    Oct 2009
    Location
    South Puget Sound/summer Eastern carib./winter
    Posts
    9,195

    Default Re: Cabosil alternative? Uses for cotton flock?

    You guys trust your fillets without glass?

  19. #19
    Join Date
    Aug 2001
    Location
    pittsfield nh usa
    Posts
    1,880

    Default Re: Cabosil alternative? Uses for cotton flock?

    I once asked my epoxy mentor of long ago about using flour for an epoxy thickener. He gave me a nasty look (lots of folks do!) and mocked using organic food stuff for thickeners. Never really explained why and I was too embarrassed to press the issue.

  20. #20
    Join Date
    Nov 2008
    Location
    West coast Sweden
    Posts
    2,401

    Default Re: Cabosil alternative? Uses for cotton flock?

    Mould? Mealworm? The ethical concerns over using food as a building material when there are starving children?

    I've been using it because it doesn't involve driving a long way to a specialty store or having to get big buckets in the mail.
    1947 Nordic Folkboat "Nina"

  21. #21
    Join Date
    Nov 2008
    Location
    West coast Sweden
    Posts
    2,401

    Default Re: Cabosil alternative? Uses for cotton flock?

    They have some cornmeal at $4.35 a pound at the local grocery I could try. It costs extra because it says 'gluten free' on the package.
    1947 Nordic Folkboat "Nina"

  22. #22
    Join Date
    Jan 2005
    Location
    Bel Air, Md
    Posts
    3,598

    Default Re: Cabosil alternative? Uses for cotton flock?

    Sanding dust, bandsaw dust, clothes dryer lint, corn starch, kitty litter, anything with a neutral ph.

  23. #23
    Join Date
    Dec 2000
    Location
    Nelson, B.C. Canada
    Posts
    2,023

    Default Re: Cabosil alternative? Uses for cotton flock?

    Yes, and you can use wooden dowels instead of rebar in cement, but why would you? Glue and fillets should do more than look pretty and and save you a couple of pennies. Last time I checked, there weren't any SERIOUS professionals using cookie dough as a filler. Get real you guys!

  24. #24
    Join Date
    Oct 2000
    Location
    Wellesley, MA USA
    Posts
    8,835

    Default Re: Cabosil alternative? Uses for cotton flock?

    Baby powder has been a popular favorite.
    A boat should smell nice.

  25. #25
    Join Date
    Dec 2000
    Location
    Nelson, B.C. Canada
    Posts
    2,023

    Default Re: Cabosil alternative? Uses for cotton flock?

    Okay, I asked for that!

  26. #26
    Join Date
    Nov 2008
    Location
    The headwaters of the Petaluma River and up a hill. ,CA
    Posts
    3,531

    Default Re: Cabosil alternative? Uses for cotton flock?

    I don't see flour as anything better or worse then wood dust for being eyed hungrily by any organic matter consuming microanimals, especially once it has formed a matrix with epoxy.
    ..don't judge a man till you've walked a mile in his shoes..

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •