Supposedly, apparently, pros use metal pistol attachments for nozzle-less expansion foam canisters. Does anyone know why?
AFAICT, the pistols are a bit costly. The pistols themselves can get clogged and add a maintenance burden. You need to then buy a can of special cleaning solution (is it acetone?), to spray through the pistol after every use.
I have always used the foam for DiYers: a canister with a nozzle and long plastic straw. The straws are trivial to work with: you twist a screw into the end of the straw when done to seal it off. The stuff in the straw still dries out but it’s easily cleared by plunging it. A coat hanger can push it all out in one piece.
Twice those things have fucked me. I buy a huge can of the stuff and use it for one small squirt somewhere. Then the stuff cures inside the can near the outlet, thus sealing it off. There is no recourse because label even tells you that you’re going to get fucked. The label says “one time use”. Indeed, they expect you to blow the whole load in a single giant ejaculation. WTF? Now I have cans of barely used expansion foam with lots of liquid trapped inside the can. I don’t recall if I tried the spraying it upside down trick to clear the nozzle.
So I have to wonder, is the pro stuff any different? Wouldn’t the pro canister outlet self-seal just the same? A hardware store near me is going out of business and I have a chance to buy a pistol at ½ price. Not sure it’s worth it.
Used both a lot in my renovation. I'd never go without pistol again.
A) it helps control the amount way better B) you can just shut it off and use the rest later on without bothering with sealing it airtight. C) better handling and weight distribution
The pistol addresses your main concern. The can stays on the pistol and is good to go even for weeks.
And the cleaning part doesn't matter to be honest. I spent a few bugs on the cleaning spray (basically alcohol/acetone solution as you've guessed) which can be easily sprayed. After use I spray a bit into the opening of the pistol.
I like to have it available in case I fuck something up or want to protect a surface, would even spend the money without the pistol.
The pistol costed like 15 Euro and saved me several hours by now.
The cleaning spray I would get even without a pistol just because it's so handy to quickly dissolve foam.
Good points. I just wanted to add to make sure you turn the flow control knob tightly off every time you are done with it. And never leave an empty can on it, change it quickly. I leave a can on mine permanently so its always ready to go. Can use a tiny amount then then close the flow control knob off. I have let mine sit for over 6 months with no issues. I only clean it rarely when I don't have a fresh can to put on. I have only gone though two foam pistols/guns in 15 years. I would never use the normal cans again. Way to much waste.
How does the nozzle not clog after you are done? Are you saying with the handle version you can screw on a can and use it every now and then?
If so that would be huge for me. As a home user I need spray foam once every few years and hate needing to buy a new can and throw out the half used old because it's clogged.
I prevent it but spraying a bit of the acetone into the tip after use.
And the screw is on the Pistole (the wheel at the rear end, looks a bit different on mine than on OPs photo but same principle).
In theory the acetone is not even needed because it has a ball bearing tip that is airtight and that prevents the drying but I never tested the concept.