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JKovats
12-29-2003, 07:31 PM
I'm doing my first coverall job. It's been a loooong time since I smelled dope (woodstock?) Anyway I'm going to use sig colours as well as clear coat (flat, it's a bipe). I started playing tonight with my sons airbrush. It's a good unit / Aztek and a good compressor.

I used some thinners and reducers, but I am not really getting the volume from the gun. Used the biggest tip 50mm, dope was thin enough, in fact it was spattering a bit. Worked best at about 20-25 lbs.

I started by building up layers on the cowl. At this rate, it looks like it will take a month to paint a whole plane. Colour is looking pretty good, I'll have to watersand to get it better. That moneycote is starting to look pretty good again.

Questions: Should I be using a bigger sprayer than the air brush??

Is my dope to thin/thick??

How about air pressure??

Does it actually take a month to finish a plane spraying it??

I think I need a bigger exhaust fan in my work shop!! I just shot a new cowl on my spacewalker II with acrylic enamel a couple weeks ago and it went on real well with the airbrush.

Thanks for any input.

John

Propworn
12-29-2003, 07:55 PM
I have found airbrushes are good for detail work but don't seam to put out enough paint to do a real good job. Try an automotive touchup gun they have a larger spray head and about a pint paint canister. Since the pigment in the dope is fairly large and the reducer dries pretty fast you might want to try a drying retarder. When we used dope we used to mix in talcum powder to seal and fill the weave of the cloth. Since most of the new fabrics tend to be of Polyester origin I have switched to a vinyl base paint called Stits. In fact I use their system with fantastic results and since it is aircraft paint you cannot get much better for scale. A few things to consider. All of these paints have very powerful solvent bases and you must have adequate ventilation or risk health problems. Second the fumes are heavier than air and will gather in the lowest part of the structure you paint in. DO NOT PAINT IN THE HOUSE the fumes are not good for the rest of the family and open flames such as furnaces and hot water tanks can cause fires. Watch out for open flames.

Dennis

JKovats
12-29-2003, 08:16 PM
Thanks Dennis. My workshop is downstairs. I have a fresh air fan intake in my family room and an exhaust in my workshop, so the fumes "tend" to stay in the workshop. I was just telling my wife I might wait till spring to finish this one. What is the lowest temperature that you would work with in the garage. Mine isn't heated, but I could put in a space heater to kill the chill and then shoot.

John

Propworn
12-29-2003, 08:38 PM
I do not use dope I use the Stits System as to temp it is designed for the home builder and lower working temperatures. I heat my garage with one kerosene heater then take it out side to spray then air out the garage close it back up and bring in the heater. I have sprayed with no effect at just above freezing.

This is the Stits site http://www.stits.com/

One of my planes on their gallery. http://www.stits.com/documents/crew_bristol.html

Some more of mine done with Stits
http://home.cogeco.ca/~denpratt2/PT%2026.html
http://home.cogeco.ca/~denpratt2/Citabria.html
http://home.cogeco.ca/~denpratt2/champ3.html

Dennis

Frank Klenk
12-29-2003, 08:53 PM
Pretty nice looking planes there Dennis! :TU:

AJCoholic
12-29-2003, 09:06 PM
Hey Frank, didnt your Marquort Charger get sprayed with Sig dope and a small airbrush? How did Wayne do it?

JKovats
12-29-2003, 10:25 PM
Thanks Dennis. Nice planes. Anybody able to answer my questions about Sig dope, being that's what I have in stock at the moment?

Thanks. John

craigk
12-30-2003, 08:53 AM
Hi
I used Sig Dope many years ago on pattern planes and I don't recall spending a month painting them. I did the work outside though, small compressor, and an automotive style gun.

base coat done in one day, then a day for it to fully dry, and trim colours after. another day to dry and many clear coats, with wet sanding inbetween

I spent more time on the hand sanding and clear coats - but the job looked nice.
now I just iron away 8)

JKovats
12-30-2003, 09:42 AM
Thanks Craig;

It looks like I'm going to have to get a bigger gun for volume. The air brush just doesn't want to move a lot of paint. I'm with you on the water sanding. I've painted a couple street rods with laquer and done flame jobs and water sanding/clear coating was always the key to a great finish. Did you ever find that dope was temperature affected when you shot. It looks like Dennis shoots the Stitts in the winter. Thanks.

John