Great Stuff Pro 14 foam gun
 

http://ecorenovator.org/forum/attach...1&d=1392231093

I know Ryland has suggested this tool on many occasions. With me having much work ahead of myself with sealing and remodeling I think it may be a good investment. It definitely is an investment at $50 when you can get individual cans for around $3. So, I would like to get some more info on it. Mainly, how does it work so that it doesn't clog up like the individual cans? I see they also sell a cleaner, but it says its only good on uncured foam. Also, the cans for the gun seem to be a bit more expensive (per volume). What other benefits does it have?

Great Stuff Pro 14 Foam Dispensing Gun - amazon.com

That gun you linked to is the exact gun that I have.
The valve on the gun is at the tip of the 8" long metal tube so you can let foam goo build up and dry and a wire brush or rubbing it on a chunk of wood will clean the valve/tip off in a matter of seconds.

I currently have a can of foam on my gun that is over 6 months old, I've used little dabs of it here and there and it works great, I have a can of gun cleaner too but I only plan to use it for long term storage of the gun, or if I wanted to sell it, the outside of the gun is all nickle plated brass and steel, with Teflon in a few spots so nothing really sticks to it for very long.

I've taken for granted how well the gun works compared to the cans with the plastic straw until I was at my brothers house filling a few holes with a plastic straw can that he had, those cans feel like they are either on full blast or 95% off, so laying a 1/4" bead of foam around the edge of a sheet of foam, or sealing in small gaps and cracks can be done very easily, mine also has a trigger stop that you can dial in and out so the trigger stops at a 1/8" bead, or 1/4" bead or 1" bead even or crank it all the way out and you can spray a foot or so and get a large void filled, altho it's a bit wasteful to do that to much, but the trigger is smooth and easy to maintain control with so you are not wasting foam.
I have not done a side by side comparison, but I have a single can of gun foam last a long time, feels like 4 times as long as a plastic straw can even tho it is only twice the size, most of this is because of the control you have over the flow, but it's also because on the gun the can is sitting upside down so you get every drop out of it and if you only use half a can next month you can use the other half.

Also, with any kind of foam like that, cover your hair, wear old cloths and rubber gloves, this foam takes almost a week to come off your skin.

Ryland basically summed it up. There is less waste. The cans last much longer. But the clincher is that you have much more control. And you don't have To use Great Stuff. There are many manufacturers of 1 part foam out there and they are NOT all created equal. I was using some (I forget the name unfortunately) recently that was crap. The bubbles were inconsistent so it wouldn't always create a good seal as some bubbles were too big. PUR seems to make a pretty nice smooth foam. Also you can use this stuff as an adhesive. It will stick to poly which is a perk. The only other thing I know of that sticks to poly is Tremco.

Thanks guys. I kinda figured it was something like that. I've used the normal cans a few times now and if you don't use it all, you most likely won't be able to use what is left the next day or so. It is quite frustrating to just throw that stuff away.

You might try and shop around for the Great Stuff Pro 14 gun. I paid less than $40 for mine at a contractor tool supply place called Western Tool. Definitely one purchase I recommend if you need to do a lot of foaming.

Looking on amazon, they have a great stuff pro 13 for about $30. Any idea what the difference is?

the Pro 13 gun is junk, lots of plastic parts like a plastic trigger, fewer parts have non stick coatings, I bought a pro 13 gun first because it was on sale and was the last one in the store used it for a few hours and had it jam up on me, took it back to the store and they replaced it with the pro 14 gun and apologized for selling me a piece of junk.