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davef
10-26-2003, 10:38 AM
I suspect this topic has been covered but I couldn't find it.

I need to epoxy teak strips to form my deck and the Gouge Bro's suggests using thickened epoxy. Thus far I've always used purchased filler from the Gouge Bro's and have no complaints.

Never the less, I have several large bags of finely milled, reasonably clean teak sawdust left over from resawing the planks and am wondering about using this for thickening the epoxy. I don't suspect I will need to do all that much sanding but am using the thickener to fill in under variations on the teak and plywood deck.

Seems like sawdust would do the trick. Any reason to think I'm making a bad mistake?

Also, on a previous post, someone was claiming that the Gouge Bro's method of using graphite mixed into the epoxy to create a "black" filler for between the deck planks was a mistake. I understand that they have experienced the graphite infiltrating the teak pores and ruining the look of the teak.

I know there are commercial products out there for getting the "black" strip inbetween deck planks. I was contemplating, however, just mixing up some epoxy with filler and adding some black Rite dye. My boat is only 20' long so I can't believe expansion is much of any issue. I think the black strip between the planks is primarily aesthetic. Would this method work?

Thanks for your advice...

Dave

Bob Smalser
10-26-2003, 11:09 AM
I used to use ebony sawdust and epoxy for high-end finishes on walnut....fill the pores with hard, black goo under a heat lamp then sand back to the wood surface after curing and apply a rubbed oil finish....the best of both worlds of durability and that warm, hand-rubbed "feel" and look. I found the dust was best made with a dust-collection sander....that sawdust from other machines was too coarse.

But when Brownells.com came out with their "Epoxy Black"...a lampblack powdered dye rather than a graphite, I stopped using scarce ebony. Works fine. If I wanted to insure I got no black bits in the face grain I'd brush a temporary coat of cut shellac on that surface and wipe down with vinegar after I set it in the epoxy, followed by light sanding/vacuuming to blend everything in and remove the shellac.

http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=1046&title=ACRAGLAS%7e+DYES

http://www.brownells.com/Images/Products/081030001.jpg

The Goo brothers also make a paste black dye in tubes that would work, too. I'd be hesitant to try home brews as these are cheap and are proven formulas. Test your home brew, first.

[ 10-26-2003, 11:11 AM: Message edited by: Bob Smalser ]

George Roberts
10-26-2003, 11:11 PM
Teak sawdust may be a poor choice.

Teak has a good deal of oil and I would expect that the bond between the sawdust and the epoxy will be weak.

Now that might not matter, but that is your decision to make.

formerlyknownasprince
10-27-2003, 03:14 AM
What about fairing the surface with filled epoxy then dynel and teak with Sikaflex seams - using bond-breaker tape?

Ian

JimD
10-27-2003, 11:31 AM
I kinda had the same idea as George about the oilyness in the teak, never tried it though but I do routinely make my own wood flour just by emptying the catch bag from the belt sander. Maybe make some flour out of a similar coloured wood?

Gerald
10-27-2003, 04:34 PM
###I was contemplating, however, just mixing up some epoxy with filler and adding some black Rite dye. My boat is only 20' long so I can't believe expansion is much of any issue. I think the black strip between the planks is primarily aesthetic.###
I would agree with Ian. I think that expansion is an issue. Sun, rain, saltwater, humidity all equal expansion and contraction. My guess is that the epoxy mixture you mention, for joints, was not a bad idea because it was bleeding into the teak but was cracking due to expansion and contraction?
Gerald

Bob Smalser
10-27-2003, 05:53 PM
I'd want to let the wood expand, too.

But I believe ebony is about as oily as teak...and I never had a problem with mixing it with epoxy...but I didn't use it for anything structural, either.

Peter Malcolm Jardine
10-27-2003, 07:16 PM
I've used teak sawdust as a thickener too, but again, for nothing structural... just makes a gap look better is all