ORIGINAL: davidgeorge212
I have heard of both ways to iron down to big balsa planks. A builder I know taught me that method of just sealing around the perimiter and using a heat gun to shrink the middle down, I have never tried it yet though. He usually sands all of his balsa planked planes to 600 grit sand paper and will iron it all down or just around the outside and shrink it in the middle depending on what the customer wants. That way if it gets all ironed down it is still gives you a very smooth surface. I, on the other hand, did not bother sanding this peice of balsa wood at all for this test so I know it shows all the grain through the covering. I mainly just wanted to see if it would stretch around tight rounded curves which it did and I had no problems with it. I dont know much about the chemical makups of these coverings but I would say they both have a clear cellophane top and a colored adhesive on the back of them. With my experience using both coverings, if you stick the adhesive sides together and pull them back apart, both coverings will pull the adhesive color part off and leave the clear see-through cellophane left.
So you did not install the covering by the MK recommended method? Which is to tack in the corners then along at certain points then gradually other points, then SHRINK as needed, etc. This would indeed imply that the covering has changed and requires different techniques (possibly cannot shrink it) for installation. Now thinking that you cannot iron down certain areas of the covering because there is nothing to iron to behind the covering this would cause some issues with the covering and this seems to be the case I am having and maybe others as well. You did mention you notice possible bubbles in the fellow's yellow.
I cut a small piece about 4x6 inches of white MK to put on the side of one of my Revolvers and you are limited to due to cut-outs for your ironing surface on the side of many fuselages just like the Revolver. You simply have no choice but to stretch the material and hope for the best when you set forth to shrink it.
Now what I found is if I cut a piece and put it on a solid surface area and iron out to the corners as you did in your project I can get reasonable results although not the same when using the recommended install procedures from MK (just throw in trash can when done and try another piece). I now realize more that there are differences due to the fact that I can cover easily over more open surfaces with my metallic plum MK but not my white MK.
Hmmmm.....because of your method of installation ("I have never tried it yet though" ...sealing the perimeter and shrinking as by manufacturer's installation instructions) you have convinced me more there are issues that MK has not addressed for the consumer and ....the saga continues [X(]