TLH101

My Feedback: (90)

I want to cover a wing with Monokote, but I don't want the wood grain to show through. Thinking about using a few coats of polyurethane or water based polyurethane, to seal the grain.

scale only 4 me

My Feedback: (158)

no need, sand the surface nicely, dust off completely,, the grain should not show through,, that's the whole idea of monokote

TLH101

My Feedback: (90)

The Monokote has to be ironed down tight to the surface to prevent wrinkles in the extreme heat we have here. You can sand with 600 or 1000 grit, but the grain still shows through on dark colors, especially in the bright sunlight.

Bill Diedrich

The thing to use is Coverite "Balsarite", it seals the wood much like clear aircraft dope.
Apply 2 coats, sand smooth and you should get the results you are looking for, and it
will also add strength to the Monokote covering material.

This is a system I have used in the past with both plastic and fabric covering materials,
only drawback is the fumes! ! ! ! !

Bill D.

scale only 4 me

My Feedback: (158)

Well if you have to seal and you choose to us WPU be sure and let it sit a week to dry, I've had issues with painting over it too quickly, it seams to take a week or so to out gas even though it feels dry and sands easy, Not sure if that would matter with iron on, but who knows.,,

good luck

TomCrump

You're right, in my opinion.

The waterborne product will need at least a week before you do anything over it. Paint and Monokote will have the same problems. Both provide a relatively air tight seal. Any water vapor will become trapped under the surface, creating blisters. This usually occurs when the airframe is placed under the hot sun.

I think that Bill's suggestion of Balsarite is a better way to go.

sensei

You are right of course, the grain will not show through on a properly sanded and cleaned surface, even in the hot sun of the Mojave desert or hear in San Antonio.

Bob

Gray Beard

My Feedback: (-1)

Sanding Lacquer Sealer works very well and it acts like Balsarite. I use it for a number of things and when Balsarite was no longer available in Calif. it was the go to product. Here in NV Balsarite is on the shelves of most any hobby shop though.

scale only 4 me

My Feedback: (158)

Yeap, it gets plenty hot up here in the summer and where I used to fly in So Cal. too, a lot of guys throw a sheet over their planes to reduce the wrinkling,

Monokote is a compromise, I say if you want a finish that's perfect and looks like paint,, You need to glass and paint

kenh3497

I've used a thinned mix of lite weight spackle brushed or sprayed. Sand and cover.

Ken