Refoam question

[Matt_E]

So...I am ready to refoam my Roundnose. I have a 5 cuft foam kit (3lbs density)

A question for the more experienced here: How do you go about pouring all that liquid into the ski that quickly?
I seem to remember there's about 30-60 seconds before the mixed liquid starts expanding.
The foam kit I have consists of about 3-4 gallons of liquid. Do you mix it in a bucket, and then pour it through one big hole? Or two big holes?
My concern is getting the entire thing into the cavity in time.
Any pointers?

 

[Phill]

Just pour into my ski and call it good!

 

[Matt_E]

Into the bilge.:biggrin:
Just so you know...I am planning on doing this today, at your house, with your foam - since mine's packed up.

 

[RMBC Freeride]

Pour in several small batches, let them expand and then cool in between each batch. Plastic beer cups for mixing/measuring each batch.

If you try to pour "all that liquid" at once...... BOOM! You're gonna have a mess!!!

 

[waxhead]

but if you do pour it all in at once
can you show us the video

 

[Mile9c1]

Yeah, take some pictures, lol.

 

[sflsurfrider]

you also want to do about 3 to 4 16 oz pours, instead of all at once, to avoid all the heat from the chemical reaction.

you want to do it in each side, left and right.

either cut a hole w/a 1" holesaw at the top of each gunwale then epoxy the pieces back in when youre done OR face the ski nose up and pour in the 2 factory holes in the firewall.


3lb density? is that structural foam?

 

[sflsurfrider]

also, if youre going to go the gunwale method, use some masking tape to make a "dam" so if foam does overflow, it goes into the tray only and not the side of your ski.

have acetone and a rag ready at all times!

 

[waxhead]

there is some good info in here
what is the std foam in a superjet
is the stuff you replace it with any lighter
or does it not make a difference

 

[sflsurfrider]

i used 4lb foam and it seems a lot more dense than the stock crap, which i *think* might even be 2lb.

heavier density = more weight but stronger and less likley to get waterlogged.

 

[Matt_E]

I am not too worried about the foam not being strong enough. I think 3lbs is a good compromise, especially with the heavy reinforcing I did on the back end.

About pouring in small batches....my concern was that the foam would over-expand and not be dense enough.

I will do the batches. That sounds more feasible. Sorry, no video.
But I'll post pics. In the past two days, I have installed my one-way (2 inches - HUGE!), put my footholds back in, and closed up the tray.

 

[Phill]

with your foam.

You Bastard!!:aargh4:

I knew you would screw me out of the foam you gave me!:bs2:




Just kidding:biggrin:


Think we have enough time to do it in the kitchen?:biggrin:
It would be much warmer:arms:

 

[Mile9c1]

It won't expand too much, it's 3lb foam when properly mixed. If it expanded more, they wouldn't call it 3 pound foam :wink:

 

[Matt_E]

I suppose that makes sense. I'll give it a shot tonight.

 

[T-bone]

stock sj comes with 2lb foam, steve recomends 4lb , i would think 3 is a good compromise.

 

[2nd nature]

crammit told me to use 2 liter coke bottles for funnels. lets see pics as your doing it . im pouring foam this month too.

 

[Mile9c1]

There's 3-4 cubic feet of foam back there. So if the OEM foam is 2lb, you'd gain 6-8 pounds of extra weight if you switch to 4lb foam.

 

[Matt_E]

Sorry I didn't post back sooner. I have or still am moving...not sure. :biggrin:
Anyways, we poured in small, 8-16 oz batches, 3lb foam.
The 3lb stuff was harder and more dense than stock foam, IMHO.

We stood the ski up on the nose, and used a funnel to pour foam in through 1 inch holes in the very back of the tray and the back of the gunwhales.
I used up about 2/3 or a bit more of the 5 cuft kit I had - this was for a complete refoam. But you have to consider the huge 2 inch one way valve with 2 inch pipe, that takes away some foam volume.

The bare hull, after refoam, weighed in at 120lbs. :bigeyes:
Strongly reinforced all over, though.