Couldn’t you just:
-Spray a safe amount of clear over the decal and its perimeter,
-Then mask the decal with something of same shape.
Then build up more clear around the masked area, remove the mask and sand it flat.

If you use 2-component clear it should be ok. With dope, I’d expect thet something shows up later due to shrinkage.🐫

L

The same issue comes up whenever I use a decal.  I blow a few coats of clear over the decal, but I'm afraid to sand away enough of the resultant hump to fair in the edge of the decal.  Is there some way you can tell if you're sanding too close to the decal?  Maybe a clear, fluorescent coat that would show up on the sandpaper under UV light?  I'm using the wonderful DBC 500 basecoat clear that Mark Scarborough put me onto, but the same would apply to dope.

Howard, I would actually do that in the catalyzed clear phase,, what I do is dust a light coat of death paint over the suspect areas prior to the application of the overall clear coat..
The DBC 500 does not have much build thickness,,,,
Of course if the decal falls across an edge, sanding and dealing with it are a real crapshoot as you know,,

I never had to deal with today's vinyl graphics or automotive finishes.  Pretty thick that vinyl.

We use the vinyl only as a paint mask.  The decals are annoyingly thin.

...except for maybe the very top fliers.

This ain't your quick finish
Applied with a mop.
The Jive Combat Team
Is the top of the top.

Hi Howard,

This how I go about making and placing decals:

I happen to have Microsoft® Word on my computer and used it to make my own decals. I believe most computers that use Microsoft® Windows has a program called WordPad that comes with the operating system. This program will work just as well as Microsoft® Word for making decals. Sorry for the Macintosh® users, but I’m sure there’s a program to do the same thing as Word. I also order “clear water soluble” decal paper for LaserJet printers. DO NOT get InkJet decal paper!

Once I’m satisfied with what I need, I create a PDF file of the Word document and transfer the files to a flash drive, grab my water soluble decal paper and head out to the nearest Office Depot and have them print the decals for me on their high end laser printers. I believe the last time I had them print black and white decals it cost me a whole 13 cents a sheet. Not too bad. Most high end LaserJets have a higher resolution and a higher temperature setting to bond the toner to the decal paper over the inexpensive LaserJets designed for home or personal use.

When applying the decals, I work one decal at a time, cut them out of the sheet, and soak it in a pan of water until it becomes loose from the backing. Locate the decal on the plane where you want it. When satisfied with the location of the decal, take a paper towel and gently remove any air bubbles, lumps, bumps and excess water. Once all the air bubbles and water are removed, I take Walthers® Solvaset Decal Setting Solution and brush it on all the edges of the decal. The Solvaset solution soften the decal and removes a little of the “hard edge” of the decals. Beware ––– Don’t be fooled just because the decal appears to be dry. I usually wait a full day or longer for the decal to fully adhere to the surface.

The decals are not fuel proof or dope proof! Once dry, I take my airbrush with clear dope and *very* lightly spray the edges of the decal and build up the edges with several coats. You are trying to feather in the edges of the decal with the dope. When that dries, I spray a couple of very light coats over the entire decal. DO NOT spray on a heavy coat over the decal as this will blister and/or dissolve the decal! The purpose of this coating is to seal and protect the decal from the clearcoat.

I sand the edges of the decal very carefully. What you want to sand is the dope - not the decal. Decal paper does not sand very well if at all.

Hope that helps.

Dennis

Here’s what I place on the side of the fuselage of my first electric plane:

solution is dont sand through

I think I need a brain replacement for that to work.  But not, apparently, Howard's, if he has the same problem.

There are products used in model railroading, Micro Sol and Micro Set, produced by MicroScale Industries. I've been trained in the use of these products and recommend it primarily for those with nerves of steel and lots of patience.

Like Howard.

dg

Howard, Howard, Howard, how many times have I told you that you should not be putting decals on your pet camel.  You are always going to end up with a hump.