Greetings Eric, Seems I find myself a little late in sending a reply... damn home remodeling project is hijacking most of my spare time so have been remiss in corresponding although I do check this site daily. I feel shame, a lot of great builds that I've wanted to comment on but have let slide... I'm going to do better soon.
Thank you for your kind comments on the Mohnicke Dr.I, it is painted (although, I do have decals for my next Fokker build). If I remember correctly, and that's questionable, I used the old Misterkit German CDL, Polly Scale Drk. Olive and Fokker Drk. Green. I think I created a paper template by drawing a baseline and then angled lines (at the angle I wanted the stripes) and taped the wing to that to paint. That way I was always fairly consistent with the angle I was painting by following my guide lines.
However, for my money (which ain't much) I'd take a look at Brad Cancian's Dr.I in the David Wilson Memorial thread. His little Revell DrI. with the streaked finish is stunning, just the effect and colors I was after... but didn't quite get. I think he may have used oils rather than acrylics which I think would be more forgiving to work with... but factor in a longer drying time.
I want to mention that there have been a lot of great triplane builds with excellent streaking effects, I picked Brad's because 1.- It's 72 scale which is what I work in and 2.- It was a fairly recent posting and is one that is fresh in my memory.
Good luck with your current project, would like to see some posted photos when completed.
Take care
Scott