Squirty foam in difficult places

[Andrew Mawson]

I need to foam seal the join between the top of a wall and some corrugated cement fibre sheeting - access is only from inside and it is at the top of the slope, (ie the roof / wall angle is less than 90 degrees). I have a foam gun and foam, but the canister has to point upwards and there IS no upwards space! Tilting the canister sideways only allows a small part of the can volume to be used and I've 40 foot to do.

I've tried pushing an extension tube onto the gun, but with the shortest length able to gain access the foam barely makes it out of the end of the 1/2" tube - any suggestions???????????????????????

AWEM

[Phil L]

Why not just use the preformed foam fillers:

[Tim S]

Andrew Mawson coughed up some electrons that declared:

This is a good question, because I will need to seal in some celotex to the wall plate...

You mentioned 1/2" pipe. Could you make an extension out of something smaller, perhaps 8mm or even car brake pipe size? Wondered if that would move the foam through fast enough before it gets lumpy.

Cheers

Tim

[Lobster]

Surely that's the answer (I was thinking of the stuff you get for fish tank air pumps). The gunge comes out of the can at a fair old lick; I can't imagine there not being enough 'oomf' available for that to work fine. Might need a few spare lengths for when they tubes get clogged up...

David

[Cicero]

=========================================

Wickes sell a '360 degree' foam which can be used at any angle. You might try some if you haven't already bought a lot for your foam gun.

I think the suggestion for flexible tubing on your existing gun (buy at Halfords as 'fuel pipe') might be worth a try but I would think that large bore might work better than small. Less resistance rather than more would seem to be required.

Cic.

[Tim S]

Cicero coughed up some electrons that declared:

Interesting - is it gun foam or standalone?

My thinking was: foam has low visocsity when it comes out the can, but that changes very quickly.

Faster you keep it moving (small pipe) the better...

Haven't tried it though, other than short pipes on my gun (6") which caused no problems.

Getting to my wall plates could do with a 2' probe at least...

Cheers

Tim

[Tim S]

While we're on the subject, do foams come in different grades of stickiness?

I've only used Screwfix No nonsense own brand, which I would describe as not

*very* sticky, but fills gaps quite well.

For sealing in celotex to dusty old wallplates and rafters, I rather fancy that something thats as sticky as a piece of jam toast over a white carpet would do the job better.

I want something that really seals up well to reduce air movement from the warm to the cold side.

Any suggestions?

Cheers

Tim

[Cicero]

I haven't tried it yet but I'm pretty sure it's standalone. I made a mental note of it having seen it just recently.

I used (without much success) Screwfix NoNonsense a few months ago and I've been planning to re-do the job (under stairs in a confined space) at some time. The Wickes 360 degree cans appear to be designed to overcome the problem of holding cans upside down.

Cic.

[gazz]

Use a holesaw to make space for the can to poke thru the roof where you need to squirt foam? :)

[Andrew Mawson]

point

sideways

They need to be fire rated so I'm trying tp use the red fire rated foam

AWEM

[Andrew Mawson]

point

sideways

something

1/2" is a tight push fit over the tube of the gun (which has a co-axial valve stem up it so cannot be bent)

AWEM

[Andrew Mawson]

message

Plonk !

AWEM

[John Rumm]

My el-cheapo gun (the £10 from toolstation) came with some extension tubes that slide over the narrowed section at the end of the metal tube. They seem to allow the foam to be piped to head of can height easily enough. The tubes are nothing like 1/2" though - more like 1/4" - rather like those on the disposable cans.

I would have thought something like a length of rubber tube as one would used on a manometer (most plumbers merchants sell it) would do nicely.

[John Rumm]

IME they all stick like shit to a blanket! (especially when you don't want them to - a can of foam solvent it well worth having to hand).

I usually get the Siroflex one from toolstation - slightly green in colour on application. Seems adequately sticky, and usually quite cheap.

[David in Normandy]

The one I use is incredibly sticky. It has even blocked the little pipe that attaches to the can on occasion. I've found the only "reliable" way of using the stuff is to empty the entire can in one go. Even a delay of a couple of minutes between squirts seems to be enough to block the pipe sometimes.

I've also had a couple of cans fail. They have refused to part with their contents while holding down the cap. I notice these cans have a use by date on them and were a few months out of date; maybe that was significant. Does the chemical go off in the can?

[John Rumm]

I can strongly recommend the gun version over the one with built in pipe etc. If you attach the can to the gun and leave it there, you can part use a can and come back to it months later; scrape any set foam off the end of the pipe and its ready to go again. Just sooooo much better than the disposable applicator cans.

Again something that seems to happen more with the self contained applicator cans. I have never really found a way of predicting or fixing the problem though - you can find plenty of horror stories resulting from various peoples attempts to poke screwdrivers in the end etc! ;-)

[Tim S]

John Rumm coughed up some electrons that declared:

You mean I used the best part of a can of gun cleaner for nothing?

[John Rumm]

Yup, I did that the first couple of times ;-) Works much better if you just leave it on the gun!

[John Rumm]

I should add, that if you do take a gun can off the gun, it is just as likely to leak and de-pressurise as the normal ones.

[auctions]

I prefer the Siroflex from Toolstation to the No Nonsense from Screwfix.

Foam tends to stick better to dusty surfaces if you lightly spray them with water first - a quick once over with a plant spray bottle is fine.

A