Recently, there have been quite a few new 3D printed units and coaches produced in Frosted Ultra Detail (FUD) that I feel would benefit from Electra vinyl overlays.

As well as the livery, these would give flush glazing and extra strength to the very fragile and brittle FUD.

It's the fragility of FUD that worries me - I have seen one seller of these bodyshells say specifically that they are NOT suitable for vinyls as any attempt to remove and reposition the stickers would break the shell.

Not having tried a FUD shell myself, I was wondering what the consensus might be - are they being over cautious or is there a real danger of the thing coming to bits?

The N-Train kits have been designed to use the much stronger WSF and Electra vinyls for the bodysides and ends so do not have this issue. FUD is just used for smaller detail, such as underframes and corridor connections.

I have designed my kits for strength. To allow handling.

I demonstrate the strength of my shells, at shows, by taking one and throwing it in the air and letting it drop onto concrete floors. I am confident that people can take my models to shows and put them on and off tracks without worrying too much about them, any more that they would with a RTR train. I do not have that confidence with FUD!!

I've done paper overlays over FUD in T without any problems, including peeling/moving/removing/destroying the overlay.  Raised detail is fragile and very easy to break off, but the shells themselves are quite sturdy.  On the other hand, the smaller size of T means a proportionally stronger shell than in N, and paper is not vinyl.  I would expect as long as you are careful with handling any unsupported middle sections of walls/sides, it would be manageable.  As usual, the only way to really find out is to try it.

I don't really see the point in putting vinyls over FUD though if you really want to then you could. The benefit of FUD is that you can paint and have an acceptable finish (which IMHO you can't get with WSF).

I can see the logic of overlays and WSF.

I have a couple of models in FUD, and I don't see any issue myself.    Yes, FUD is a little fragile, but I would never have thought that vinyl's would do any damage?