I was hoping to get some info on this subject. I would like to paint my twin F-18 with an automotive base clear. I am fighting the weight game and would like to hear some real numbers. I have been told 3-4 pounds, what have you experienced?

This is the scheme in question is the one below. I can use the primer that is on the plane for the bottom, they are very close. How much weight will this add? Keep in mind the fuse is 8 feet long.

Kenny, I weighed my Isobar Dry at 29 pounds in primer before 50 flights.

After 50 flights, took everything out and painted it and then restuffed it.

Reid and I were curious and we were both there for the first weigh in and we were both there for the second weigh in.

We used a base clear PPG Omni.

Astoundingly the jet came in at 29 pounds the second time around on the same bathroom scale as before. Given a little bit of error in the scale, my guess is the paint probably weighed shy of a pound. Another way to think about it is that 16 oz of paint weighs??? And then take a 70 % transfer of what you load in the guns or some percentage based on HVLP technology and you'll come close as to what you've actually gotten to stick on your plane.

I doubt it's gonna be 3-4 pounds on the bug, although it might be that with primer and any misc body work total?

Thanks Sean!

Come on guys, Sean can't be the only one that weighs his planes before and after paint!

Kenny,
Try to get most the primer sand off. You just want enough to cover your glass. Flat colour scheme doesn't weight that much. It only require 2-3 light coat over the primer will do the job.
Aplly more PPG 2060 flat clear over the decal. Kept it light coat on the area with out decal. This also can help to reduce the weight.
Flat clear is very easy to apply. 2 light coat should be enough.

Sport colour scheme with high gloss clear coat weight alot more.
I don't have exact weight for the paint.
But it be interested if you can weight it.

Brg,
Tam

Thanks Tam. I sanded most of the primer off. The colors will be flat and I will keep in mind to ad more over the decals and less everywhere else. I will get a before and after weight and advise.

Anyone else?

Sent you a PM Tam.

I wouldn't worry. I know jets are probably slightly different in paint techniques but say for instance a 2.6M Composite-ARF Extra or Yak. Painting it from scratch adds about 1-1/2 to 2lbs of weight MAX. This is a plane with a 104" wingspan and 91" in length.

Kenny,
Base clear is probably the lightest paint method you can use. If you are doing a flat finish, as Tam said it's easy to keep it light. 2 coats of clear is all you need, you can get away with one coat if you're good at spraying.
When I did Dean's Kingcat I added 24oz in paint, when you consider the size (probably close to the same amount of surface area as your 18) and the fact that it was a high gloss finish sanded out and buffed (which required 4 coats of clear) this is pretty reasonable. The sanding of the clear probably reduced the weight a bit. You can't really judge what the finished product will weigh based on what your raw paint weighs either even based on the amount of paint lost in spraying (70% as sean said) as most paints will evaporate a solvent during cure. Especially base. The RAW weight of paint on Dean's Kingcat was probably about 4 pounds, to end up at only 24 ounces in the end shows how much of that weight evaporates during cure.
Dean's jet also used a lot of pearl and Kandy colors which increases weight due to heavier base colors. White and Red are the 2 heaviest colors, the pigment is heavy. When you add metallic or pearl flake it adds a bit more too, it may be negligable, but we're talking weight here. Dean's jet was first entirely sprayed with silver (a heavy color to start) then gold (another heavy color) then Kandy red, Kandy pearl purple, and Kandy blue. Then the airbrushing took place. For the checkers this all had to be based in white again. As you can see, I used many colors, and ended up with very little weight for such a large aircraft

Here is the kingcat in question





I'm just putting this picture in to show the depth of the clear, this isn't done with one single coat

Thanks Shortman. I can deal with the 1-1 1/2 pounds, but any more and I may be rethinking the scheme. Buck has a very effective, simple, and light paint scheme. I just don't want the paint to be the reason I am not drinking 120 beers at BITW...

2 pounds isn't much on a 2.6 Yak, but it is huge on this plane.

Thanks Jeremy!

That is good to hear. I can see that there was a lot of clear used over many different colors. (Looks awesome) It makes me feel better knowing that there was 1.5 pounds added with all of that. I have only 2 main colors and a few color accents. The grey for the bottom can be sprayed very light because the primer is about the same shade. The black should cover really well also needing very light coats.

Thank you guys for setting my mind at ease! If you have any suggestions on how to "fade" the black on top to make it appear weathered please let me know. Thanks again to you all.