Johnny's HK Flowmaster

[Prodrvr]

The 115 cutter works awesome, but man you better have a steady hand!! After I removed those aluminum plates that the stingers get screwed to, I started buzzing the globs of epoxy out of the way and slipped a tiny bit. Now I have what looks like six pin holes through the hull on the outside, just above and to the right of where the stinger goes. But I'll fix that up with the gel coat when I get to that point.

[TheShaddix]

Well, that's a good one, but i was referring to one of these http://www.ebay.com/itm/5-9-inch-Dia...AAAOSwqu9U~uqA

Also, this one http://www.ebay.com/itm/Beta-Tools-1...cAAOSwqv9V6Gaw

[Prodrvr]

The second one you linked I have. Didn't think of using it though lol. I'm hoping to finish the interior clean up this weekend. Nothing I have ordered has showed up yet, so at least the hull will be ready for the foam and cf when they do show.

[TheShaddix]

Are you planning to use expandable foam? Be super careful. In fact, i'd advise against it unless you plan on reinforcing the upper and lower areas of the bow. It will bow out and distort like crazy otherwise. The hull is just too thin.

[Prodrvr]

Yes. but I was going to do it in stages just to avoid the problems you speak of. Here's the stuff I'm using...https://youtu.be/s0-yGzcLFhM I'm using the 610

[TheShaddix]

Doesn't really matter if you do it in stages or not. It will distort the hull in stages too and create a lumpy surface. It's the heat of the chemical reaction and the overall expansion force. Not worth the risk. The upper deck is very flimsy so even the slightest pressure will mess it up. Either reinforce it or avoid the foam and use pool noodles cut to fit the bow area. I've seen every hull distort regardless of what foam I used. The only hulls that did not warp were heavily reinforced ones where I used 12k carbon in the bow section. If you decide to do the foam anyway, at least use a fan to blow air into the hull as the foam expands. Don't use water to submerge it because the water pressure will compress the hull as you dip it in.

[Beaux]

I used the spray foam in my hornet from hk in the sponsons and about two week later it started contracting, I had to get in there with a hacksaw blade and cut it loose, after a couple of days the sponsons returned to their original shape. So be careful
that flowmaster is a good looking boat.

[kfxguy]

Never ever never ever use spray foam. I ruined a hull with it just experimenting. I use two part foam. Pour it in on the floor and move it around on the floor and let it rise from the floor up. If you stand the boat on its nose (did this one time) then it will rise and then suck the bow in. I know this for fact.

[Prodrvr]

Never ever never ever use spray foam

Agreed!!

[Prodrvr]

Doesn't really matter if you do it in stages or not. It will distort the hull in stages too and create a lumpy surface. It's the heat of the chemical reaction and the overall expansion force. Not worth the risk. The upper deck is very flimsy so even the slightest pressure will mess it up. Either reinforce it or avoid the foam and use pool noodles cut to fit the bow area. I've seen every hull distort regardless of what foam I used. The only hulls that did not warp were heavily reinforced ones where I used 12k carbon in the bow section. If you decide to do the foam anyway, at least use a fan to blow air into the hull as the foam expands. Don't use water to submerge it because the water pressure will compress the hull as you dip it in.

Now I asked the company about curing temperature and was told that if I only mix up 2oz. at a time, it will not go over 180*. Now I don't know if that's enough heat to F it up or not. If you watched the vid I posted, they did the experiments in solo cups...and those things are thin crappy plastic, with what seems like no effect to the cups. I'll try doing the foam little by little and see what happens. If I really screw it up, then I'll just sell off all the guts and buy a hull that's already reinforced.

[Prodrvr]

I just had this crazy idea...so let me know how crazy this is. What if I wrap the hull really tight with duct tape? There's no way the foam will have enough force to move that tape.

[Prodrvr]

https://youtu.be/Of1RY4M8VqM Craziness!!

[Beaux]

I agree with kfxguy never ever never ever! From experience Bad idea.

[TheShaddix]

But over time the foam will distort a bit as the weather gets hotter/colder and your hull will follow along since it's glued to the foam. It happened to the flowmaster I built. When I did the foam it did not affect the surface at all. Then, when I sold the boat months later, the guy noticed all the warping, and there is simply nothing you can do to fix it. i used the 2lbs density one that you can get on kintec which is the best for the job as it's very light and doesn't cause much pressure. And you can do all sorts of tests in a plastic cup, it's not a good example. I was a huge proponent of this foam a while back, but the more I use it the less I like it. It's a great idea for when the hull is very strong and you don't care if it gets damaged, but otherwise some nicely cut foam noodles will do just fine.

[Beaux]

That's what I've been stuffing in mine.