How much primer?

[mhorowit]

How much primer does it take to spray the fuselage? - Mike

[Pearson]

Re: How much primer?

Mike,

Ten different people will take ten different amounts of paint to do the same project. It all depends on your technique, the type of spray gun you are using, how thick you want to coat it, and on, and on.

I can tell you that spraying the round tubing of a fuselage is going to waste a lot of paint. You can minimize the amount of waste by using an HVLP gun, turning the air pressure and paint volume down low, and taking your time. If you crank the air pressure up and open up the paint volume, and then spray with the gun a foot from the tubes, you will be finished quickly but you are going to use a LOT of paint.

So with all that said, get a couple quarts and start spraying. When you run out, go get more. Don't mean to be a smart ass, but I don't know what else to tell you. If you keep the amount of paint coming out pretty low volume, you can control how thick you apply it how fast you move the paint gun. This will also help prevent runs. Also by using low air pressure and paint volume, less paint is going up into the air as overspray. Adjust the fan so that it is just a small round spot. By doing this you can get by with amazingly low air pressure. You should be able to get a round spray pattern about an inch diameter about 5-6 inches from the tip. If you come to a cluster and want a larger spot, just pull the gun farther from the work and move slower. The closer you hold the gun the faster you have to move. Also if you paint outside and it is windy, triple the amount of paint you buy. I hope this helps.

[mulwyk]

Re: How much primer?

Mike:
I used one of those quart kits of stits epoxy primer (the kit actually contains 2 1/2 quarts). I put on two coats the first day and then a third coat a few days later. I used a conventional spray gun (not HVLP) with the fan control turned way down so it was shooting a "round" pattern. The first coat was very light, the second coat much heavier into the almost dry first coat. After the third coat I had about 1/4 of the quart kit left over. (You can probably use less if you have a HVLP gun, but maybe you don't want to use your expensive, fancy new spray gun for primer, if any of the epoxy sets up in the gun it's destroyed.)
You'll need some way to turn the fuselage, I used the simple H-frame and saw horse method shown in the polyfiber manual. And be sure to allow lots of time to paint all those tubes on all sides ...it takes much longer than you'd imagine.
Have fun! (but don't breath the fumes)

[Pearson]

Re: How much primer?

Mike,

If you don't have an HVLP spray gun, or don't want to use your good gun for primer, Google "Harbor Freight" and do a search for "ITEM 94572-0VGA". You get TWO HVLP guns for $60. Or go to;

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94572

As with any tool, if you take care of it, it will last longer. Get some CHEAP laquer thinner and use lots of it to clean the gun when you are finished. Have several rags available for cleaning also. After you rinse out the cup and spray wash thinner through it 4-5 times, use a rag to WIPE out the inside of the cup. Then wipe off the outside of the cup and the gun. After you have sprayed the wash thinner through the gun several times unscrew the tip about a half a turn. Then while you are spraying, dab your finger over the hole for just a split second. This will great back pressure and clean out the back side of the mixing orifice under the tip. Make sure you have the lid on good because it will kick up a geyser inside the cup. If you are going to use the gun again later that day to spray the same paint, that is clean enough.

If you really want to make sure you have everything cleaned out good, unscrew the tip and use a wrench to remove the orifice underneath the tip. Be careful not to ruin or lose the gasket beneath the orifice. Make sure the cup is empty when you do this. Soak the tip and the orifice in laquer thinner for an hour or so. You can use the bristle brush that comes with the gun to clean both of them. You can unscrew the paint volume knob on the back of the gun and remove the needle. This will allow you to use the brushes to clean up inside the gun. When you reassemble the orifice and tip, be sure to put the gasket back the same way it was. Use the wrench to just snug it tight, but not too tight. I always run another bit of wash thinner through after reassembly just to make sure any loose stuff is blown out before painting.

[Hank Jarrett]

Re: How much primer?

I have told the story before and gotten lots of laughs but I primed and painted my fuselage tubes with a $4.00 Harbor Freight plastic airbrush. It had a fan of under an inch, did a GREAT job putting down two coats of Epoxy primer and one of Epoxy paint and used SIGNIFICANTLY less materials. Funny part was it really didn't take any longer than with a Jamb Gun except for refilling the stinking tiny bottle. I changed to an old Honey jar that fit with a longer pick up tube and the process went really fast.
Everybody at the airport laughed till they saw how well it worked and I pointed out that my new sports car was parked outside the door and didn't get the slightest bit of over spray on it.
start by reaching THROUGH the tubes to paint the tubes on the opposite side (facing the inside of the fuselage) and the clusters. Then paint the outside of the fuselage. You will smear lots less paint on your arms. ;-)
I also got two colors of primer, red and white. The red showed really well on the freshly blasted fuselage and the white showed really well on the red. For a paint coat I used a color mix that matched the Zinc Chromate that was used at the factory.
Hank

[mulwyk]

Re: How much primer?

Hank, you're onto something with that airbrush. I was so frustrated painting my fuselage with a full size spray gun (half the paint blows right by the tube you're painting) that I actually considered using a paintbrush. An airbrush would be great for painting all those small parts too. I'm gonna get me one this weekend.

[mhorowit]

Re: How much primer?

Hank - is this the small sprayer with non-standard tubing so you have to do some jury-rigging? - Mike.

[Hank Jarrett]

Re: How much primer?

The airbrush is really CHEAP so buy several (I had one for each color). If you can go through them, look for the ones with GLASS paint jars, the plastic jars are junk (and we are talking about Harbor Freight here). Go to a hobby shop and they will have an adapter that goes from a standard compressor hose fitting to the tiny tube fitting on the airbrush hose. Also, get one of the little regulators with a water filter at Harbor Freight. Mine has a pressure gage on it and I made a belt clip to hook the regulator to my belt so the big hose gets dragged by my waist, not the tiny hose. Nothing like having the airbrush jerked out of your hand when the hose gets caught on something.
Hank

[flyguy]

Re: How much primer?

I'm not painting anything just now, but this sure is good information. I have been thinking of the trim on my 12D that could use some new shiny red on it. That idea with the 2 different colors for two coats is clever.

Think I will buy a touch up gun or two from Harbor Freight. The Chinese ARE going to need some more money that they can loan back to us. Chuckle.
DC

[Hank Jarrett]

Re: How much primer?

I have been using two coats of different color primer for years. Only problem I have seen is when you use red tint for the lower coat sometimes it will bleed through the white. Nice thing is when you get enough primer on to cover the red you know you have a good coat of primer. ;-)
The best thing I think I did on the 45 fuselage was the Zinc Chromate color epoxy paint over the primer. None of the glues for fabric that I know about will melt it when the covering goes on. If the fabric glue melts the paint on the steel tube, well, you have a bare steel tube! RUST CITY!
The most important thing when working with epoxy is WEAR A RESPIRATOR! Painting the inside of your lungs makes you fly at lower altitudes (I am giving up trying to convince people who paint without protection of the health hazards, hit them where it HURTS! Make em think they won't be able to fly any more.)
Hank

[O.Taylor]

Re: How much primer?

Ever see the old Piper videos where the guy is putting the zinc chromate on with a hose??, it's great. O.T.

[Ray36048]

Re: How much primer?

Don't laugh, but I have painter several with a hobby paint brush. No wasted paint and better coverage. The foam brushes from the craft store also work well. Very easy to miss the back side of a tube using a spray gun.

[Hank Jarrett]

Re: How much primer?

Use the different colors for each coat priming method and you won't miss the backs of tubes. The red primer shows really well against freshly blasted steel and if you do miss a spot, the white primer REALLY shows any missed spots where the red is still uncovered. I came back a week later and there were some little dots of rust in the nooks and crannies I re-spot-blasted and double primed (red, then white). Any small rust spots will pop through the white primer really fast, especially if the coat is thin (which it would have had to be over a spot you missed with the red). Even if you DID miss a spot with the red, the white was plenty of primer, especially when sealed with the Epoxy paint top coat.
Hank

[Jim Doody]

Re: How much primer?

http://www.toolparadise.com/ For less than $100 you can get yourself a quality tool that will do the job all the way through the color coats. I used a Sharpe FX300 for my plane, it did a great job. Search e-bay for a fresh air supplied paint hood and buy a quality respirator for all paints not catalized. Do not believe that a respirator will protect you when using catalized paints, you MUST use a fresh air supply! Don't buy any of that Chinese junk, we are in an economic war with them. Jim