I can't it has been this long since Larry Render put us onto using SLC(super light covering from the Corehouse) over poly-span(available from Stunt Hanger Hobbies).   The planes I've done it on and now using different materials has worked great and been real durable.  Of course the covering doesn't stop an EX-Acto knife from going through blade first.  I now use Pellon P45 JAS interfacing from the fabric store and the mylar is listed as Clear Super Flite Mylar Model Covering on the Ebay.  The seller is shown as day_trader. 


Now my method is to coat the perimeteror of the wing and surfaces that the Pellon is going to be adhered to using Mod Podge from the fabric store also.  Use a chip brush or foam brush to apply it.  I let it dry while I cut the materials to size.    I start wit inboard bottom wing and iron the Pellon down trying to get out as many wrinkles as I can.  I do this dry as I found out the hard way it does not like to be put on wet.   Once it is done all around including over lapping the wing tip I then go back over the main portion to take out the sagging that does appear and most of the wrinkles if any.  It will streach over the wing tip if you are careful when laying it down.   Once that is done I rhen apply the Mylar also trying to get it on with out too many wrinkles.  Make sure when you over lap the pellon you get to wood/balsa surface.   Once that is done and all the over hang is trimmed off you can go over it with the iron to take out the wrinkles you can.  Don't worry about getting them all out at this time.   Now grab the Mod Podge and lay on another over the edges of the mylar that the top side Pellon will need to adhere to.


While that is drying you can now do the sam procedure on the bottom out board wing.   When done with it including the Mod Podge it is time to do the top side in board wing.   When you get to the wing tip you may have to use a little more Mod Podge which will steam when the iron hits it.   Let it cool as you go.   By now the scrap has been trimmed off an you can do the top side out board wing.  When done with the scrap on it you will see some wrinkles the iron didn't take out.   This is when the hot air gun comes into play.   It takes time and patience(which I don't have) to get 99% of the wrinkles gone.   You will see some light colored areas where you now take your iron and run it over the open areas to make the mylar adhere to the Pellon.   By the way you did save your scraps as if you hold the hot air gun in one place too long there may be a hole appear.   Cut a peice of scrap in an oval or circle and iron in place.    From a few feet away you will not see the patch.   Hopefully it didn't get the Pellon too, but pay attention and it shouldn't be that bad.


By the way yellow is MonoKote on the planes with Pellon under neith o hide the wood grain.  Now I need to do the graphics and trim on the planes.   I know this is long but is much easier to do than tell how to do it.

Ummm, something lost in the translation? 

Look at it now.  Fat dumb fingers and lousy keyboard.

   Not trying to be a naysayer, but how do you finish over mylar? Nothing sticks to it, so how do you get the paint to adhere?

    Brett

I had the same thought, but if you go to the ebay site he details how to apply paint.
https://www.ebay.com/itm/Clear-Super-Flite-Mylar-Model-Covering-6-x-25-Alt-to-Monokote-Ultracoat/252184975362?epid=1256898443&hash=item3ab7655802:g:0XkAAOSwVFlT-u9J:rk:1:pf:0


Perhaps his mylar has has some surface prep to allow paint to stick?
There are both chemical and non chemical ways (plasma treatment) to increase the surface energy.

   Not trying to be a naysayer, but how do you finish over mylar? Nothing sticks to it, so how do you get the paint to adhere?

    Brett

With thicker mylar it's not a problem, just sand matt and use 2 pack car paints. It's a quite standard finishing method in eastern Europe, and chez Beringers, for example.
But how to sand the very thin mylar over something else without weakening it too much, that's a good question.
I'd just forget the polyspan or silk and just use thicker mylar. L

Motorman what makes it lighter is the lack of all the dope that might have been used.   I don't dope any more.