For quite some time we have been wanting to get a Spray Gun attachment for our compressor. We sometimes have large projects to put a finish on, and thought this would be the easiest way to go about it. Besides, the guys you see using them in videos and adverts are having so much fun and look so cool. Well, as it came to pass we got one for Christmas last year.Pakaging for Critter Siphon Gun

What we received was the Critter Air-Powered Spray Gun from Lee Valley Tools, Ltd.  Now, at first glance it isn’t very impressive.  I mean it’s small, about the size of a cheap garden hose nozzle.  It weighs about the same too. If the box didn’t include a Mason jar you would swear it was empty.  But it only  takes a second to realize that there are no cheap plastic parts, the nozzles and fittings are brass, and the stem is stainless steel.  As always though, the proof of the pudding is in the eating …. 

We had to wait a couple of months until we had a project of such sizable dimension as to warrant the use of the spray gun.  We had been expecting to wait until warmer spring weather so that we could try it outside. However, Rosemary’s Cupboard came about and was just screaming for a coat of polyurethane. 

Out came the gun, a quick read of the instruction sheet, grab a couple of mason jars and fill one with some leftover polyurethane from another job, fill another jar with paint thinner, grab a scrap piece of wood, fire up the compressor, stick the jar of urethane onto the gun, connect the air hose,  OMG we were having so much fun, just like those guys in the adverts …

Now, it should be stated that for safety reasons the follow is advised:

  1. Wear Personal Protection Devices – goggles, mask/respirator, a hat, coveralls, proper footwear,
  2. Work in a Well Ventilated Environment – the sprayer essentially atomizes the liquid you are applying to the material, and a lot of it will remain airborne reaching dangerous levels very quickly,
  3. Be Aware of the Fire Risk – if the finish you are using is flammable, it will be even more so when it is airborne, sparks, cigarettes, open flames should be extinguished or removed if there is any chance that they will come into contact with the airborne particles. 

Of course, we didn’t have any of that ready.  We knew we should, but that would take extra time and we wanted to play with the new toy. 

So, standing there in our street clothes with only a dust mask for protection, we closed the doors to the workshop (didn’t want the sound of the compressor to bother the neighbours, and it was 4°C and raining outside), adjusted the pressure on the compressor, and pulled the trigger … nothing happened.  A lot of air, bit no mist.  We had started out with the compressor set to about 30 psi, but remembered that that was the setting for thin fluids, polyurethane is pretty thick so we would have to turn it up.  We tried a few more times, raising the pressure with each go until we finally reached 70 psi and a beautiful, fine mist blew away from the gun at quite a fast rate, straight across my router table.  Thank god we had thought to get the paint thinner out.

After cleaning off the router table, and throwing drop clothes over it, the table saw, shelves, and workbenches nearby, we tried again.  This time we had it all right.  It worked great.  Nice clean lines, easy to control the spread, and the amount of spray.  We felt that it was time to turn this on Rosemary’s Cupboard.  This is where the gun surprised us the most.  We had been testing a semi-gloss finish, but wanted to apply a satin to the cupboard.  No problem.  Fill another Mason jar with the satin polyurethane, take the semi-gloss off of the gun and put a cap on it, put the Mason jar of paint thinner on the gun and shake it around a bit to clean the stem, spray it into a waste bucket a few times to clear the nozzle, then swap that jar out for the satin finish, and we’re ready to go.  It was really that easy!

The size of the cupboard allowed us to test the sprayer at a lot of angles.  Vertical sides, tops and bottoms of shelves, even slopes when we had to lean the cupboard over to get at the top.  It performed wonderfully the whole time.  The coat apllied nice and even, without runs or streaks.  After applying a coat to everything however, you couldn’t see the other side of the shop for all the polyurethane floating in the air, and it’s a small shop.  That’s about the time we woke up and remember that we shouldn’t neglect basic shop safety. 

While we were spraying we had heard my wife get into her car and drive off.  She usually parks in front of the large shop door.  I figured we could clear the air quicker by opening up both ends of the shop and letting the wind blow it all out.  I threw open the back door,  and depressed the button to lift the large door.  The wind whipped past me picking up clouds of sawdust and depositing it on all the surfaces we had just sprayed, and blew all the floating polyurethane straight out onto the hood and windshield of my wife’s car.  I guess, today she had chosen to take my van.

When the air was clear we closed the doors, cleaned up the gun, put everything away, and headed back into the house.  A quick trip into the washroom to wash up,  and I discovered why cover-alls, hats, and the other personal protective devices are so important.  Every inch of exposed skin, every hair on my head and arms, my clothes, everything had a very thin coating of polyurethane.  I looked like I was covered in a fine frost.  Fortunately, it hadn’t properly set so getting it off was fairly easy.  Had it been on there longer I would have been looking at a sponge bath in paint thinner.  Not something I ever intend to try.

So it was an adventure.  But these are the kind we like – if bad things didn’t happen we wouldn’t have any stories to tell.We’ll have to do a little extra sanding between coats, but nothing was ruined.

Over the next few days we would be applying several more coats.  During these coats we experimented with adjusting the nozzle to deliver different amounts of fluid.  We found it very easy to control, and after a little playing we found a pressure and nozzle setting which worked very well for the polyurethane.  We were also very careful to wear the appropriate clothing and gear, and to ventilate the shop more carefully.

Critter Air-Powered Spray Gun Reviewed:  9 out of 10!  It was amazingly easy to use and clean.  It did everything it was supposed to. The Mason jars make everything so simple, and you don’t have to go out and buy a special paint bottle like most manufacturers make you do.  Its light weight really becomes important after waving it around for an hour or so.  There were only two problems we had (that were not our own fault). First, when you have the hose connected to the gun, you can’t sit it down – it’s too back heavy.  We overcame this by clamping a short bar clamp to the underside of the worktable and hanging the gun over the bar (there is a little hook on top of the gun). Secondly, filling the Mason jars from a full 1 gallon pail was a bit of a pain.  We ended up using a ladle, after spilling it all over the place on the first try.  We’ll be looking around for a better way and let you know if we find something.

So at the end of the day, the Critter Air-Powered Spray Gun is worth every penny!

Check in next week when we’ll be featuring Rosemary’s Cupboard.

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