Thinking of spraying, but...

[RedShirtGuy]

In my quest to cut down production time I've started thinking about being able to spray both polyurethane and shellac finishes on my makings. I make things like shaped/flat puzzles, kids toys, the odd small box and am heading into larger things like easels and kids furniture. The smaller items are a bit of a pain (in terms of coating time) to do with a brush and because I tend to make things in batches of half a dozen or so it really stretches things out to have to do everything seperately.

Is it reasonable to think that I can save a decent amount of coating/finishing time, particularly on fiddly bits, and what am I looking for (beisdes the seemingly generic term HVLP) in the way of equipment to run off a compressor?

Not knowing a heck of a lot about spray finishing, are the cannisters of finish able to be used, then taken off the gun and sealed to store the remainder for later use (between coats and over longer periods of time)? Naturally the gun would be cleaned between uses or as neccessary.

Would something like an artist's airbrush be suitable for smaller jobs? (The ones that take a little jar rather than a small well on top of the gun)

Cheers.

[joez]

RedShirtGuy, Spraying should save you a fair bit of time especially if your doing multiple items.

You can premix and store your finishes in a large mixing cup (with lid) and it will keep for a while.

Clean up depends on the material being sprayed, my suggestion would be to start with shellac and say pre-cat lacquer. They both behave very similarly and are very easy to deal with and clean etc.... In most cases you can rinse the gun 2-3 times and get away with it for cleanup in the short term. The other bonus is the items will be touch dry and ready to handle in a couple of minutes.

As far as a gun goes, just go for a generic hvlp auto type gun, no matter what size you choose you still need to clean and maintain it, so the size isn't too crucial.

I would suggest you look at a gravity fed HVLP gun, a standard 600ml gun would be the best all purpose choice. Your paint supplier should be able to help with the gun (< $100) and recommend a tip size for your finish. The other item that will save you time is a lazy susan style table.

One negative of spray finishing is that a lot of the stuff ends up in the air, so you will use more finish and need to make sure you have the appropriate safety gear (gloves, respirator, eye protection).

Sprayfinishing isnt hard, but does take practice so be prepared to have a play to get things working the way you expect, you will also notice that the finish will keep getting better as it dry's, (if you can smell the finish its still drying) sometimes the worst finish will look brilliant after 24hours...


good luck

joez

[munruben]

Good advice there Joez, I am pleased you mentioned the amount of material needed in spray finishing, so many believe that spray uses next to nothing compared to a brush finish, in fact spray finishing, whether it be paint or another type of finish such as stain or lacquer, will use more material than application by brush simply for the reason explained in Joez's post above.

Personally, I would mix just about enough material for the task in hand, you will soon get the hang of estimating the amount you need to complete a project. That way you don't have to be concerned about storing left over material although it can be stored for a short period of time.

Spraying small fiddly bits is far better than brushing a finish, it is faster and once you get more experienced with the equipment you are using, the finish is far superior. The speed in which a project can be completed is worth the effort alone.

Good luck.

[RedShirtGuy]

Thanks a heap guys. Been away for a while hence the slow response.

I pulled out some of the old man's dusty old spray gear just for a play using some water and was surprised at just how quickly it went through a cannister. It might be a bit of a catch 22 with wasted finish versus time saved but I'll give it a go and see what I can come up with.

I can see a definite advantage for lacquering photos on boards for jig saw puzzles and being able to do half a dozen at a time. Although I'm a bit iffy about how much is to be gained when doing other smaller, fiddly, pieces as they usually have to be fully coated all over. How I position them in the spray booth is probably going to be pretty critical for getting the most coverage with the least waste. A little trial and error is coming my way me thinks

[Master Splinter]

For small stuff, an air brush is quite handy, and they have small screw-off jars so you can keep leftover paint for another day..but the jars are small, so it's not really a lot of leftover paint! You don't need one of the fancy dual-action air brushes, just a cheap $25 one and fittings to run it from the compressor (mind the pressure!!)

Next step up from that is a touch-up gun, but the jump is a bit like going from a dremel to a 1/2 inch router in one go.