8255 Build

[T.S.Davis]

I'll make a mold and lay on up.

I did one like this for a Norte Dam that we left the foam in and just glassed it over. Weight is an issue on this thing so I'll do a light layup on it. Having the mold I'll be able to just make another if we wreck it.

[longballlumber]

Sanding and fairing and sanding and fairing.

DO-DA, DO-DA, All the Livelong Day....

[T.S.Davis]

I could pour the mold full of hydracal and vacuform from that. My machine can pull about 26" length. Haven't used it in ages though.

The sanding fairing routine is pretty critical. The more I do now the less crap that will show up in the mold and the parts that come out of it.

[T.S.Davis]

Double post

[T.S.Davis]

Well, I'm satisfied with shape. Cockpit needs more work but it's close. So I'm switching to good ole spackling to fill pin holes. You can skip this step but when you spray primer onto a surface with pin holes you trap little pockets of air. The air will come out if it can but usually it gets trapped in the primer. You sand the surface and guess what you have.........stink'n holes to fill.

The nice thing about the spackle is that it's softer than the epoxy I'm filling. So sanding it flush is pretty painless.20150225_204623.jpg

[ron1950]

hey terry do u think this process could make a 10th scale turban hatch? if so u could make a few bucks selling those :)

[ray schrauwen]

I've tried spackling compound and, Byron Jet pin hole filler on a PTSS and a Whip cowl and the schtuff just falls out of holes and whatever, just no darn luck with pin holes. I think that's why I like either gel coat FG hulls or wood to build with. I hate finishing pin holed surfaces, it makes me complete irate.

[Shooter]

I've had awesome success with the spackling compound. I use it and/or elmers wood filler. The fact that it sands down quicker like Terry said is a huge advantage. I had major reservations at first, but Klasskote works great to seal it all.

[Shooter]

Ray - are you rubbing it on with your fingers? Rolling it around until half dry? I find it adheres best that way.

[ray schrauwen]

I found it dried very fast and didn't seem to stick very well.. i need to repaint the cowl anyway it was such a quickie before the nats. The PTSS was not as bad.
Maybe I didn't clean it well enough before?

[T.S.Davis]

hey terry do u think this process could make a 10th scale turban hatch? if so u could make a few bucks selling those :)

yep. The mold would need to be two piece though. Have to make gates for that. Just another step.

[T.S.Davis]

Pete, before you prime, what are you wiping your surface down with?

[longballlumber]

I am sure that Pete's process is similar, but this is what I do.

Tack cloth and wipe down with a good epoxy thinner (with gloves) then shoot Klass Kote primer.

Later,
Ball

[Shooter]

I use a dab of the KlassKote thinner on an old T-shirt (low lint). Wipe it down, then blow any contaminants off with air prior to spraying. If you use a tack cloth, don't press too hard, or residue will be left on the surface. I've been avoiding them lately because some brands are really shoddy.

[T.S.Davis]

Epoxy thinner? Like acetone or alcohol? Or are you talking actual reducer on a rag? I think this is where I ran into problems before. I used a product made by HOK that's supposed to be for this but I don't think it worked as described. Supposed to remove grease, wax, and any oil from your fingers. Paint still flaked off in sheets. IDK

I have the Klasscoat primer. Still have to get some white though. I have aluminum Klass for the Thomas. Need a weather break. Lots O' painting to do. 9 degrees in the garage.

I'll use the primer on this plug before I mold it. More sanding............sigh. Polishing. You would not believe the finish you can get on quality primer. It's so workable. When you finally get to the release wax stage it even takes on a shine.

An even better idea for a turbine cowl would be to con Pete into modelling and milling one. Then mold that part. You could still mill it from foam. Then go through the sealing, sanding, priming, polishing, molding process. At least the symmetry would be dead on that way. Hmmmmmmmm

I'm with you Ray. Give me a gel coat boat any day. The only down side to that is that you don't really know if there is any bridging between the gel and the actual composite. The gel could look fine until the first time you tap a buoy. Gel is like paint. Almost no strength. I just put my head in the sand and hope for the best. haha Also, if you buy an epoxy hull with a gel coat the gel coat is polyester and the layup is actually epoxy. Two different animals. So the gel to FRP bond is actually mechanical instead of a chemical. Same as paint really.The difference between gel and paint being that the gel is sprayed into the mold before the glass.

The nice thing about the Klasscoat is that it too is epoxy. That's likely why it works so well.