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# Thread: Filling nose cones with 2-part foam...

1. ## Filling nose cones with 2-part foam...

I need to fill an Estes Leviathan cone with foam. It's 3" round and about 11" long from tip to tail.

I ordered some 2-part foam from Public Missiles.

How much do I need to mix?!

1/4 cup A and B? A cup?

And how big of a hole do I need? And I suppose I need a funnel and a cold water bath (with ice)?

I am expecting the foam in a day or two.

2. Well, since you ordered it from Public Missiles I assume you read or have the ability to go back and read the full page description they have on their website (hint: they also link to pdf sheet of specific instructions on how to use their foam, which probably will also be included with your foam when it arrives). PML sells a kind of two-part foam with variable expansion rates, from 10 up to 25 times its liquid volume. So.....

1) Figure out what expansion rate you want, more or less dense foam? Why are you foaming this nosecone, are you just using it to lock in some noseweight? Less dense should be fine.

2) Figure out the volume of your nosecone. You can approximate, just treat it as a cylinder instead of a cone, this will make sure you have plenty. (Interpolate and knock off 20% if you want to be economical or have less cleanup.) Use google to figure out the equation for the volume of a cylinder. Use a calculator to figure out the equation.

3) Use your answers from 1 and 2 and some more math to figure out how much of Parts A and B you want to mix.

4) Also don't be afraid to use the search function here to browse through earlier threads on "two-part foam" for additional tips, I'm pretty sure you will find some. Drill a big hole, too small and it will be harder to pour in. You don't need a funnel, just mix in a disposable cup and pour. Having a bucket of cold water ready in case it starts to get too hot isn't a bad idea.

3. Thanks, Beezwax!

4. Whenever I foam up anything, I do it in batches - I mix about 20 - 30ml at a time and pour it in. Wait for it to foam up and then add the next layer.

Your working time is pretty short and the foam expands pretty quick, so it doesn't take long even if you have to make up 5 or 6 batches.

Krusty.

5. And to add to Krusty's 'batch' technique, I would pour the 2 parts in separately..Pour part A in then part B, twirl the nose cone to get them to mix and watch the 'magic'..That way the foam won't start expanding in the cup prior to you trying to pour it and once it starts(expanding in the cup) it WILL make a mess!

6. Originally Posted by Pantherjon
And to add to Krusty's 'batch' technique, I would pour the 2 parts in separately..Pour part A in then part B, twirl the nose cone to get them to mix and watch the 'magic'..That way the foam won't start expanding in the cup prior to you trying to pour it and once it starts(expanding in the cup) it WILL make a mess!
How well does the stuff need to be mixed? Just twirling, sloshing it around in the cone mixes it well enough?

7. Originally Posted by majordude
How well does the stuff need to be mixed? Just twirling, sloshing it around in the cone mixes it well enough?
No. Must be mixed thoroughly and rapidly in a Dixie cup or other container. Then contents poured into nosecone or other cavity.

8. Originally Posted by dixontj93060
No. Must be mixed thoroughly and rapidly in a Dixie cup or other container. Then contents poured into nosecone or other cavity.

Then contents poured VERY RAPIDLY into nosecone or other cavity.

9. I know some people have poured the two parts down with a bunch of airgun BB's, then shaken vigorously. The BB's help mix it, and work as a nose weight.

I have never done it though. I've only used the single part stuff that comes in a can, which kind of sucks.

10. Originally Posted by majordude
I need to fill an Estes Leviathan cone with foam. It's 3" round and about 11" long from tip to tail.
Just curious, why?

11. Originally Posted by Handeman
Just curious, why?
Putting BBs in the nose and don't want them to come off. The foam will hold it in place and add extra weight.

12. Not to be funny , but you might want pics of this process and post them so others can learn. A biohazard suit is a good idea the first time as is a voice activated phone for the call your gonna make----and you thought epoxy was messy----honestly , I'd do a test run first if this is your first time--just to get a feel for it--no pun intended--H

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Words to the wise ...

Follow PML's instructions EXACTLY TO THE LETTER. The stuff grows more than you might imagine. Since this is your first attempt at 2-part foam, I highly recommend you mix a small test batch and pour it into something you are willing to throw away (i.e. a small paper cup) before the real batch that goes in your nosecone. If you overfill you will have a real mess on your hands and trying to intervene just makes it worse.

--Lance.

14. Damn it! How hard can this be? I wish I could pour in water, top it off, poor it into a cup that says, use 2oz of each for this volume.

15. Originally Posted by hornet driver
Not to be funny , but you might want pics of this process and post them so others can learn. A biohazard suit is a good idea the first time as is a voice activated phone for the call your gonna make----and you thought epoxy was messy----honestly , I'd do a test run first if this is your first time--just to get a feel for it--no pun intended--H
Originally Posted by llickteig1
Words to the wise ...

Follow PML's instructions EXACTLY TO THE LETTER. The stuff grows more than you might imagine. Since this is your first attempt at 2-part foam, I highly recommend you mix a small test batch and pour it into something you are willing to throw away (i.e. a small paper cup) before the real batch that goes in your nosecone. If you overfill you will have a real mess on your hands and trying to intervene just makes it worse.

--Lance.

What they said......

16. Maybe I'll film my 1st attempt, upload it to YouTube... and go viral.

17. Originally Posted by majordude
How well does the stuff need to be mixed? Just twirling, sloshing it around in the cone mixes it well enough?
It has worked very well for me in the past..Foamed up quite nicely and filled the cone when I last did it..

18. How much working time is there? I mean, I measure, mix... and WHAM! or 5 minutes later it activates?

19. Originally Posted by majordude
How much working time is there? I mean, I measure, mix... and WHAM! or 5 minutes later it activates?
I use he stuff from US Composites, you get about thirty seconds to make up your mind - cant imagine its much different with the stuff you have.

20. 30 seconds?!! Dear god. This will be EPIC.

Titanic. Hindenburg. Me. (Not necessarily in that order.)

21. Originally Posted by majordude
30 seconds?!! Dear god. This will be EPIC.

Titanic. Hindenburg. Me. (Not necessarily in that order.)
LOL

And thus the reason for little batches

Krusty

22. It's not that bad really, but always better to go small and have everything in place before you mix. For what you're doing here, I'd start with about 3/16" of each part in a paper Dixie cup, no more.

23. Originally Posted by krusty
LOL

And thus the reason for little batches

Krusty
And the gloves, etc.

Join Date
30th August 2012
Posts
1,403
Originally Posted by o1d_dude
And the gloves, etc.
+1 on the gloves. and cover anything you don't want foam on with masking tape.

25. why do I get this picture of a foam fountain?
rex

26. Originally Posted by Rex R
why do I get this picture of a foam fountain?
rex
Foam volcano

27. Krusty

28. 1 - watch this http://www.youtube.com/watch?v=zAIY0I5GGw4
2 - small batches
3 - find something, anything, that you can 'practice' fill, old nose cones, a spare body tubes, a large red Solo Cup, etc. practice you first attempt to foam fill something on this.
4 - clean up the mess
5 - go back to the small batches method
6 - attempt the nosecone job whilst videoing the event for our amusement.

Good luck, it is an experience.

edit---
never, ever, not joking here, remove both caps at the same time.

Last edited by Salvage-1; 18th April 2013 at 10:47 PM.

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