my new carbon fiber cheetah!

[kfxguy]

I know you guys gonna think im crazy but I pick up two cans of great stuff large gap filler. For an experiment I put some in a hull that's trash first. Just to see. I made a blob of it darker and let it dry then submerged in water and it didn't hols any water and was very bouyant. Whsts so bad about using it? Yea it expands but wont it expand back in the the open space?

[rickwess]

As long as it's a closed cell foam, it would do the trick. I personally like to laminate it for aesthetic reasons.

[srislash]

Great stuff can expand more up to a week later. It has happened. It expands when it reacts with the moisture in the air when it is released from the can. A trick is to apply in a steamy shower to make it react quicker/fuller. If it were me I would glass tape the seam before I put foam in it.

[kfxguy]

Great stuff can expand more up to a week later. It has happened. It expands when it reacts with the moisture in the air when it is released from the can. A trick is to apply in a steamy shower to make it react quicker/fuller. If it were me I would glass tape the seam before I put foam in it.

Man I'd like to reinforce it but its so thin and tight up in there, I can't get in there. I can fill it half way and wait a week. That's what im gonna do with my other hull I sprayed it in just to see.

[srislash]

Hey, if you are going to do this, you mind weighing the hull before and after foam? Just curious.

[Fella1340]

I would be Leary of it. I have seen it used in real boats, mind you the foam was often left saturated
In water. It was a real mess taking it out and it was almost completely saturated. I worry about further expansion down the road to. Its possible for parts of it to not cure at time of sealing and expand at a later date. I realize that you.could.seal it up with glass and never look at it again but...couldn't you achieve almost the same thing with pool noodles? There hias to be a better way then using great stuff in your in your beautiful new boat. I wouldn't trust it not to expand again on you later and possibly stressing the hull when you fill it. I would use it between a 2x4 but that's it! Don't so it! I have seen guys that use a 2 part foam that expands accurately to a given volume and even this is added in small amounts at a time. If you add to much to you area it may damage your hull. Don't do it!

[srislash]

Man I'd like to reinforce it but its so thin and tight up in there, I can't get in there. I can fill it half way and wait a week. That's what im gonna do with my other hull I sprayed it in just to see.

So are you looking at foam as floatations or strength? You could put a couple stringers in there if it is strength you're after. If floatation, I think that hull has room enough for pool noodle. At least enough to float it. Especially if you seal it well.

[Fella1340]

I would be Leary of it. I have seen it used in real boats, mind you the foam was often left saturated
In water. It was a real mess taking it out and it was almost completely saturated. I worry about further expansion down the road to. Its possible for parts of it to not cure at time of sealing and expand at a later date. I realize that you.could.seal it up with glass and never look at it again but...couldn't you achieve almost the same thing with pool noodles? There hias to be a better way then using great stuff in your in your beautiful new boat. I wouldn't trust it not to expand again on you later and possibly stressing the hull when you fill it. I would use it between a 2x4 but that's it! Don't so it! I have seen guys that use a 2 part foam that expands accurately to a given volume and even this is added in small amounts at a time. If you add to much to you area it may damage your hull. Don't do it!

[kfxguy]

Here's my shockwave I put the foam in. Its hard already. I did it about 2 hours ago. I hope the outside didn't cure before the inside..if so im in trouble lol. I don't care, I messed this hull up anyway and its an experiment. Notice proboat sprayed in strikingly similar foam. You can see a slight color difference.


20131110_172227.jpg


Btw, I want it more for flotation than anything. Yhw extra strength it may bring is just a plus.

[Fella1340]

I was just thinking that if you had a mishap with the boat, accidents happen:) and you needed to
Do a repair say if you smashed in a sponsor tip. It may get really ugly having to pull that stuff
Out to make a repair. Yes, a lot of guys have used it successfully but they likely didn't have
any accidents that required an inside hull repair. Its good, its bad. Whatever works for you is
All that counts anyways. You know what they say about opinions........j

[Fella1340]

I would think proboat used polyurethane foam that is used in real boat building.
Uscomposite.com sells it. There may not be a perfect answer. I am only being the devils
Advocate here. I don't want anything to happen to your beautiful new boat. If you go ahead
And do use it it might be an idea to complety seal it off so moisture doesn't get in at all.
Anyboat big or small if its on the water moisture/ water gets in everywherer. The large gap
Filling foam expands so much I wonder if it dries properly inside. Can you do a test patch on a board
The same size as you are going to do and see if the inside is dry or using the same amount of time
That you were going to use before you did your next spray over the first and then checking the inside
For dryness. I am just thinking aloud here. Doing that may give you an idea on how much time is needed before first spray is covered over. Just to be on the safe side. What does the can say for complete drying time? If you follow the directions and error to the high side if time to dry before spraying next section it might have better success. You probably have thought of all this already and think I should just shut up about it. I just want this to be a complete success for you and it seems
others experience is either great or it has turned out very bad. I have seen the bad side of using this
This hence my concern using it. I hope it all goes very well.

[kfxguy]

Hey, if you are going to do this, you mind weighing the hull before and after foam? Just curious.

Yea I will. No problem. That stuff really doesnt weigh anything tho. We shall see

[kfxguy]

I would think proboat used polyurethane foam that is used in real boat building.
Uscomposite.com sells it. There may not be a perfect answer. I am only being the devils
Advocate here. I don't want anything to happen to your beautiful new boat. If you go ahead
And do use it it might be an idea to complety seal it off so moisture doesn't get in at all.
Anyboat big or small if its on the water moisture/ water gets in everywherer. The large gap
Filling foam expands so much I wonder if it dries properly inside. Can you do a test patch on a board
The same size as you are going to do and see if the inside is dry or using the same amount of time
That you were going to use before you did your next spray over the first and then checking the inside
For dryness. I am just thinking aloud here. Doing that may give you an idea on how much time is needed before first spray is covered over. Just to be on the safe side. What does the can say for complete drying time? If you follow the directions and error to the high side if time to dry before spraying next section it might have better success. You probably have thought of all this already and think I should just shut up about it. I just want this to be a complete success for you and it seems
others experience is either great or it has turned out very bad. I have seen the bad side of using this
This hence my concern using it. I hope it all goes very well.

No man, no problem. I welcome everyone's opinion. That's why we are all here. Ill tell you this.
, the foam in my proboat stock and this other stuff I put in look just like each other in texture. The great stuff is shiny and non porous looking. Lighter color one is great stuff

20131110_184503.jpg

[tiqueman]

Please don't great stuff that hull. Its nasty, looks like poo, warps decks, hulls etc and once its in your done. No longer will you be able to make a repair from inside if ever needed. I'd run my $5k hpr with no foam before I put that crap in it

[Rocstar]

Listen to others, or find out for yourself...your choice. Here is a hull I had to work on. After a crash the water expanded the foam to bust open the hull worst then the damage from the crash. Repair was very difficult.

These pictures are after cutting away some of the expanded foam.
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