puddler10

Hello,this is the best forum I have ever used to get information. I am building my second plane -a Sig Hog bipe I understand that some areas bubble with Monocoat no matter how its applied. My question is- will sealing the balsa and poking the wood with a pin before covering be a benifit or a waste of time. Can I use any sealer -will the covering stick to say lacquer thinned with solvent -I build furnature and wish to use something I have on hand .
thanks for any info.......
Michael

Joe Ortiz

My Feedback: (75)

I got a Hog Bipe for my winter project, I cant speak for monocote, I'm using ultracote, I'm currently using water base sanding sealer, made my wing sheeting stronger, I'l be sanding today and covering next week, I read on this forum that it should be no problem.
Joe

EdwardB

My Feedback: (6)

I would personally be very careful of any type of sealer, at least without testing first. Two problems: (1) one of the main reason for bubbles is trapping air between the covering and the surface. Adding sealer makes that problem sometimes more difficult, (2) keep in mind the heat you use for covering is likely well above the melting point of the sealing products. I had the brilliant idea of putting a very thin coat of white primer on a sheeted wing because I didn't like how the balsa grain showed through the white covering. When I tried to cover I had a giant mess. The primer melted, and the covering looked like it had a bad skin condition. I ended up removing it all, and glassing and painting the plane.

Two suggestions (1) whatever you do, test it first on scrap pieces using the exact processes. Only when you're positive it will work do you commit it to the airplane itself. (2) take a look at a product made for this purpose. http://www.coverite.com/accys/covr2500.html works pretty well, and will really make the covering permanantly attached. Note they have two kinds -- one for film, and one for woven type covering.

I personally have had the best luck by making sure the surface was well sanded with 400 - 600 grit paper (at least. It should almost shine), perfectly clean (vacuum and tack cloth), the exactly right heat temp, and push the covering down with kleenex tissue after heated. If you really insist, holes punctured with something like a TF woodpecker perforating tool will let air out, but I've really never found this necessary if you start from the center out on solid surfaces.

DBCherry

My Feedback: (4)

For sheted surfaces, Monokote actually recommends a different procedure for covering. Rather than stretching and tacking the corners, sealing the edges, then shrinking; they suggest ironing the covering down in the center, then working your way out radially, so the edges are the last part you adhere. While I haven't tried a whole surface, I've used this method with smaller trim pieces with good results.

And I second being careful with adding anything under the covering. Almost anything will off-gas some type of vapor that will cause bubbles.
Dennis-

Azcat59

I would stay away from using anything on the wood beneath the Monokote (or Ultracote). And I am not big on the Woodpecker idea either. Solid surfaces is where the guys have problems with the covering gassing up and later showing bubbles. This ony bothered me for about 16 years, until a Sgt. in the Air Force transferred here, and gave us a lesson on how he covered so well. Use a "sock" on the iron, and turn the temperature way down.....like about 1.5 to 1.7 on the Top Flite iron, which as I recall is about 200 degrees. Cool enough that, when you put the iron down on the covering, it is slow to radiate out wrinkles, and then only big gentle "waves", not tight hard wrinkles. Be prepared to work very slowly, and iron down every inch of the covering to the wood. You can go back over the perimeter with slightly more heat when you are done just to make sure it is down well, but don't linger with the iron, or it will gas on you.

Some guys that really Monokote well have told me they sand with 400-600 grit paper. And their work is something to be admired. However, I have made up test panels (glue some 3" wide 1/16" sheet to a pine 2x4), with part of it sanded as they say, and part sanded only to 220 grit or so. Once covered, darned if I can tell the difference. It seems to me that the 220 scratches are smaller than the balsa wood grain "channels" which you can never eliminate. I don't argue with their advice, but I quit at the 220 stage.

And....for a little extra "stickum" at firewall edges, wing saddles, wheel well edges, etc. where the film is more apt to come loose, rub a small ribbon of Sigment model cement into the wood along the edge you want to nail down. It heat activates like Balsarite (only better). Try it!

Clair

Live Wire

Just finished a SIG t34 mentor. used latex sealer, wood pecker, iron and heat gun. Must be doing every thing wrong. Looks great had to wipe down with lightly with thinner before covering to get covering to bond the way I wanted it to but looks great . The wood in the kit was dry and the sealer gave it some life. What I used was ACE 16063 sanding sealer and it doe'nt take much. You can use it under paint to for a base. $.02

CafeenMan

The Sig hog cries out for a cloth covering. Why not use SolarTex or Coverite instead? It's more durable, will last longer and bubbles aren't a problem. Plus, in my not-so-humble opinion, your bird will look much nicer.

MinnFlyer

My Feedback: (4)

I have found that plane ol' white glue thinned with water makes a great sanding sealer. Just brush it on, let it dry, and sand it with 400 sandpaper. It comes out as smooth as a baby's behind.