I discovered the trick to applying Ultracoat over itself by accident. I was doing a repair and I had the iron temp set very low. The temp knob on my iron is covered up by the rag I'm using as a sock so I couldn't see the dial. At this very low temperature you can lay ultracoat down over itself, bubble free, at a pretty rapid pace. It seems to work equally well over sheeted and un-sheeted surfaces. You have to move the iron rather quickly in a kind of swirling motion and work your way across the surface in a methodical way.

Compared to the windex method this is slightly more labour intensive but you will be done long before the windex dries so it's faster.

I dont know what the magical temperature is (edit: it's about 210F measured through a sock). In later experiments I found that if you are getting bubbles it's a sure sign that the iron is too hot. My theory is that a hot iron heats up the covering to the sticking point that it is not directly pressing down on. So the covering sticks and forms air bubbles. With a cool iron, the covering doesn't get hot enough to stick unless it's directly under the iron. That lets you press all of the air out and get a nice bubble free result.

This is certainly a skill/technique thing but then covering is all about skill and technique.

On the rolls of ultracoat, it has a flyer that tells you what temp certain things happen. IIRC, 220 is when the adhesive activates, and max shrinkage is 350.

Actually your best bet is to use monokote to trim over ultrtacote. Windex doesnt activate the adhesive on ultracote but does so very well on monokote. So basically when I cover an airplane I cover it base color with ultracote and then cut my trims from monokote and windex it on. Although it is possible to put ultracote over ultracote with low heat, as you discovered, it is time consuming and still doesnt produce as nice a finish as with monokote

@Huckin Chuck - Yes, the flyer they provide is actually very detailed. I never seem to have a temp gun around. If I was really smart I would mark the spots on my iron dial where these different temps are.

@Dr. Yankem - Sometimes the right color is only available in Ultracoat and the design dictates what goes on top. Having a bag of trick that lets you do any combination is important. Also I dont think windex activates the adhesive. It's more an effect of the residue in the windex bonding to the adhesive and the covering underneath as it dries. That technique doesn't work on Ultracoat because the material has microscopic (well really tiny) ripples. These ripples pop away from the surface below defeating the windex.

Here is the real trick in applying Ultracote over Ultracote or MonoKote that I have been using for building over 300 aircraft for customers and myself in the past 20 years.
Here is what I use, Ultracote as the top layer, heat gun, spray bottle with soapy water, and a squeegee about 3”x3” made out of 3/32” balsa (use the grain vertical to the film surface).
Like when using MonoKote as the top layer, you “float” the film on top of the base film, but unlike MonoKote instead of using Windex that has an ammonia base you use a spray bottle with water and a very small amount of dish soap in it. The technique once you have the base film covering on the model is to spray that finish with the soapy water, place the Ultracoat piece that is already cut to size and shape in position. Use the balsa squeegee you made to get the bulk of the soapy water out, now comes the trick, while working the water out with the squeegee, use the heat gun first at a fairly good distance and slowly move it in closer as you squeegee the water out. What happens with Ultracote that while you are working the air bubbles out the adhesive begins to activate and you will be able to tell when the Ultracote is fully adhered to the surface. This technique is easy and fast and you are done with each added piece now, and you can move on to the next.
I use both MonoKote and Ultracote, and this soap process only works with Ultracote, for MonoKote I use Windex and wait till the next day and go over the edges to make sure it sealed.
Tom

Cool Tom, Thanks for sharing your technique! I will have to try that out.

@ Tom!

I have been using monokote since the 80's, and just started using Ultracote/monokote combinations with no real issues. Looking forward to trying that trick out soon!

I have a question. When using the Windex method, will Econokote stick down like Monokote does?

Bill Hodges

Thanks Tom, your process for Ultracote over Ultracote is right on the money. I will send some pics later but the Hanger 9 , 3.1 Suhkoi in orange pretty much was invisible for me at times and I put the Purple over the leading edge and matched the Crème and Silver sweeps to give me a good perspective of the planes attitude out on the edges of the box. I did it in one afternoon with the templates already cut and practiced on a spare wing. I used a sock and heat gun predominantly along with low temp iron w/sock. worked great!! I'm going to cover the underside Orange checkerboard with Purple next.

Thanks, I'm currently working on covering a plane with ultracote, and I really have to try this technique.

Jim