2 part foam question

[gsbuickman]

Hello everybody,

I am going to be foaming up the hull of my villain, and I was wondering about the 2 part expandable marine foam. Usually I use the spray in window & door foam, but that won't work in this application.

I understand the part a and part b expandable foam from Kintec is 2lb per every 1'squared. Each kit comes with 3oz of part a & b. My question is, what is the rate of expansion after mixing equal parts, or what is the mix ratio ?.

thanks.........

[tlandauer]

Mixing ratio is 1:1, I used small amounts ( equal of course) to see what the rate or expansion is, although I did not measure in a scientific way. I used two epoxy measuring cups:http://www.offshoreelectrics.com/pro...od=dh-gpmr8056 for both A & B, then dumped them into a disposible party drinks cup, quickly stir and pour. You have very little time. Do a practice run.
Label the small cups because you can reuse them,the party drinks cup is a throw-away item.
On those epoxy cups, I poured 15 ml A & B into each cup for one time, wait until the foam fully expands in your boat before the next round. Also you should do this at least above 70 F*, I remember people saying that if it is done on cold environment, it can give a false impression that it has fully expanded, and come a hot day, you are in for a surprise.Once it's there it will be hard to remove all that stuff, i remember you had water intrusion issue on your Vallain, I would make sure the issue is gone before doing this, just my $.02
Good luck and have fun, I did it in my Miss Geico after a nasty flip. So far so good.

The best that I can tell about the expansion rate is that I did more than one pour ( two, three at the most, it's been so long that I am a bit foggy) into the front deck of the MG, 15 ml in each cup, that is. Also this form does have a finite shelf life, mine had been sitting around for more than a year, so my observation of the expansion rate may not be accurate!

[Cinnabun]

If I remember correctly the instructions that come with the kintec foam say 30x expansion rate.

[gsbuickman]

Kool, thanks guys. The reason I ask, is because I am looking for a pourable foam that I can pour into the bow of my villaIn, then tilt the hull so the foam runs into the empty cavity in the rear of the hull. Then I can fill the bow :-) .

Any recommendations, so I don't have to drill a hole in the rear deck to add foam ?.

Expandable foam uses moisture in the air to expand. A good trick is to set the hull in the bathroom, close the door, and turn the shower on with straight hot water. The bathroom gets steamy, the temp goes up, & the foam expands to its full rate :-) .

[rickwess]

You have more working time than you should need. I didn't time it, but if you use small batches you can easily mix it thoroughly in 10-15 seconds. It's probably another 20-30 seconds after that before the reaction kicks into high gear.

I measure in the small epoxy cups and combine/mix in a small dixie cup. Once the expansion starts, you won't have much control over the uniformity of the coverage. That's why you pour small batches. You can direct the next pour into any gaps that may have formed between the hull and the foam.

When in doubt, practice. You will see there is nothing to worry about.

[tlandauer]

Thanks for the "hot shower" tip!
I don't remember how far the foam has to travel, my Vaillian is not stored here so I can't see exactly what you are talking about.The reason I am saying is that the last thing you want to happen is for the foam to expand before destination, just think out loud...

[rickwess]

Expandable foam uses moisture in the air to expand.

That may be true for the foam in a can. The two part foam is strictly a chemical reaction.

I snagged about 10oz of each from the shop who built my J-Craft. They had 5 gallon drums of the stuff. The bow of the boat in my avatar is pretty much full of foam.

_DSC4602.jpg

[gsbuickman]

That may be true for the foam in a can. The two part foam is strictly a chemical reaction.

I snagged about 10oz of each from the shop who built my J-Craft. They had 5 gallon drums of the stuff. The bow of the boat in my avatar is pretty much full of foam.

[ATTACH=CONFIG]107307[/ATTACH]

Thanks for the clarification. Judging price v's weight, pour foam seems a Lil' pricey. Here's a link to the site with the best deals I've found on foams.

http://www.uscomposites.com/foam.html

4lb. kit / 2 square feet $22.50 v's '$20 @ Kintec for 6 oz.

[jcald2000]

I have used the 2 LB. foam for years form US Composites along with their thin epoxy. 4 lb. is twice as heavy.

[Jeff]

and the 8 lb is twice as heavy yet.

[rickwess]

Those small cans will last for many many boats.

[gsbuickman]

[QUOTE=rickwess;535316]Those small cans will last for many many boats.[/QUOTare you referring to Kintec's 3oz of part a&b for $20 Rick ?

[rickwess]

[QUOTE=gsbuickman;535416]

Those small cans will last for many many boats.[/QUOTare you referring to Kintec's 3oz of part a&b for $20 Rick ?

No, the small can from US Composites.

[gsbuickman]

Kool, thanks Rick.

[rickwess]

4lb. kit / 2 square feet $22.50 v's '$20 @ Kintec for 6 oz.

Get the 2lb foam though. Less dense means more air for buoyancy.

Even the 2lb foam adds unbelievable rigidity to bow of your boat.