Setting some "epoxy" records straight

General Discussion
1

OK. I have read and read and until I think i have it and read more until i am confused on what to do again. I think it is because some of the archives i have read have some updated methods.

1? Marko Foam EPS. I am specifically asking about this pressure molded stuff and hand layups. I have some 1.9 and 2.3. I believe that i do not need to seal it. But has anyone found that it is still an advantage to seal it? ie you are able to use less resin during the lam? Is there a difference in final weight? Microballons- What are they? Different from silacell and cabosil?

2? Fin Boxes+RR Fast Hardener=?

I am curious as to what is the best way to install fin boxes(lokbox in this case) Is the fast hardener ok? How do you minimize exotherm in this step. On lamintating you pour out of bucket asap. What are some of the ways you guys do it for fin boxes? Also chopped fiber vs cabosil vs staight lam? I read to do it all three ways.

Thanks for any help to the tons of questions. I am just trying to minimize my trial and error. This is fun…

2

1 prefill all eps blanks and they will come out lighter ,even if you prefill polyurthane blanks they will come out lighter

2 prefill with 3m k1 glass bubbles they are stronger and lighter than anything, mix 5 to 1 with resin or to a thick paste

3 use slow hardner with fin boxes if it exotherm past about 180 deg f it will melt the blank

4 pour out as much as you need to wet out the flats and use the rest to do the lap

hope this helps god bless richard

3

…sealing with microbubbles (Silica Dioxide - hollow glass microspheres, NOT microballoons) not only reduces resin migration into the foam during lam, but also slows an gassing issues you might have due to ambient temp changes. Do seal… for a lighter board that won’t leave you with dry spots (if temps are falling) or outgassing bubbles in the cloth (if temps are rising) when you lam. I use a 50/50 ratio of resin and microbubbles so it goes on really smooth and easy, and I squeege it as perfectly as possible so I only touch it with sandpaper.

Use slow hardener if you can, but you can use fast. Just make sure you put some cold, wet rags under the deck where the fin box is going to absorb any excess exotherm. I mix in some microbubbles to thicken it just a bit, and don’t put anything in the hole. I install the box over one layer of cloth after lamming, then put a patch over the box, then fair it out before the cheater coat. Then I sand, then final hot coat. You don’t need cloth in the hole unless you have no stringer.

4
Quote:
OK. I have read and read and until I think i have it and read more until i am confused on what to do again. I think it is because some of the archives i have read have some updated methods.

1? Marko Foam EPS. I am specifically asking about this pressure molded stuff and hand layups. I have some 1.9 and 2.3. I believe that i do not need to seal it. But has anyone found that it is still an advantage to seal it? ie you are able to use less resin during the lam? Is there a difference in final weight? Microballons- What are they? Different from silacell and cabosil?

Jeff Johnston, who sells the Markos here never seals any blanks. He does, however cheater coat them. I spackle, unless requested not to.

2? Fin Boxes+RR Fast Hardener=?

I am curious as to what is the best way to install fin boxes(lokbox in this case) Is the fast hardener ok? How do you minimize exotherm in this step. On lamintating you pour out of bucket asap. What are some of the ways you guys do it for fin boxes? Also chopped fiber vs cabosil vs staight lam? I read to do it all three ways.

The fast hardener with RR resins is fine with Futures, OFishl and Lokbox. It is often 88F in my factory and I set the above fin boxes all day with fast hardener with no problems. The Aluzine, however, over about 85F ambient, can have some problems with Futures, which have a looser fit into the blank. You will not have a problem with exotherm using RR and fast hardener unless you’re glassing in Death Valley.

Thanks for any help to the tons of questions. I am just trying to minimize my trial and error. This is fun…

5

Bammbamm

Thanks. Those were the answers i was hoping to hear from someone with experience with those blanks. So are you then spackling for show purposes? Does JJ spackle his boards if they are to be airbrushed? What spackle combination do you recomend? Thanks

6

I don’t know whether JJ has done any airbrushed EPS boards, however, I belive you would have to spackle them. Even the most careful shaper would have difficulty getting a finish that you could airbrush on, I think. We’re about to do some test pieces of spackle with airbrush for a series of boards a client wants done.