How to fill in rivets on skins

nippaero · #1 10-01-2007, 10:50 AM

I have a question on how to fill the rivets on the exterior of the airplane for a smooth glassy look. I have noticed several RV's over the years that have all the rivets filled and painted over. Some builders fill the tail while I have seen other planes where you can hardly spot a rivet on the whole plane. They almost look like a composite airplane. What is the process to fill in the rivets? Someone mentioned that you could use a filler/primer. What products are used? Does anyone have a good write up with some pictures? How much weight would it add to the airplane?

RV7Factory · #2 10-01-2007, 11:11 AM

Mike, there might be a few small places where rivets or seams get covered (i.e. empennage tips), but overall - don't do it! You'll add weight and time. You're building an aluminum airplane, be proud of every rivet you set!

PS - Great avatar!

lostpilot28 · #3 10-01-2007, 12:03 PM

Just my 2 cents...I like the smooth look a little better. Yes, I'm still proud of the rivets I set, but I'll have the logs, pictures and data plate to say that I built it.

I would think that a smoother surface would allow for a slicker airplane. I wonder if that would be sufficient to overcome the weight penalty of the filler/primer.

szicree · #4 10-01-2007, 12:17 PM

If you fill just the rivet you'll still have a slight depression in the area around it. I'd say the depression is maybe an inch or so across and very shallow. To fill all of these to the point that the plane looks like a composite would add quite a bit of weight. I've seen em like that, and they do look slick, but I wonder about weight and longevity.

rleffler · #5 10-01-2007, 01:03 PM

My concern would be, what happens if a rivet starts smokin? Seems to me that might cause the filler material to crack or pop.

nippaero · #6 10-01-2007, 01:09 PM

I agree about the additional weight. I tend to fall into the build it light and simple philosophy. I am more interested in the how it is done vs. the weight/performance debate. The planes that I have seen had pretty elaborate paint jobs so maybe the paint shop did all the work willing and prepping the skins. There was a really nice guy up at Arlington this year. His plane was green with the card decks... The rivets were filled and it looked amazing.

Brian Vickers · #7 10-01-2007, 01:28 PM

I have been thinking about this myself. Low airplane weight is my goal. I want to shoot one thin coat of primer, and then one coat of top paint. I was thinking of slightly thickening some PPG DPLF primer with flox or micro and then squeegee it on the rivets. Wipe the excess off with a rag and solvent. My goal is not to hide the rivets or make the indentation disappear. I only want to fill the circle (gap) around the rivet. I have read previous posts where people have applied multiple coats of primer and or topcoat to accomplish the same thing. With my method you wouldn?t see much, if any primer or filler around the rivets prior to the single primer coat. Only the gap around the rivet would have the material in it. I don?t think it would take that long to pre-fill all the rivet gaps.

Thoughts on this idea?

Sincerely,

Brian Vickers, RV4 finishing
Bainbridge Island, WA

Mel · #8 10-01-2007, 01:34 PM

Brian,
The problem with this method is that every rivet would be different. This would not be appealing. Either fill them completely or leave them alone.
If you fill them completely you will add much time and weight. I've done it. I would never do it again.

DaX · #9 10-01-2007, 01:46 PM

If you're dead set on doing it, what about some lightweight body filler, like Evercoat Rage Gold?

cln1owner · #10 10-01-2007, 02:09 PM

Met a guy at this years Arlington airshow. Green RV-8 with a gambling themed paint job, playing cards on the wing and some very nice airbrush work. He had everthing filled, very smooth, looked like a composite aircraft. Very beautiful job. For the life of me I can't remember his name, maybe someone here knows. Anyway, he mentioned that the paint job added 30lbs to the aircraft.