Making your own decals with an ink jet or laser printer is getting better all the time.
Step one is to get yourself the correct paper. I've had great success with
Micromark
http://www.micromark.com/and BelDecal
http://beldecal.com/inkjet_decals.cfmThere are two kinds of paper - clear and white. You can use the clear paper for all decals that don't have the color white in them, or light colors like yellow that need a white base. In those cases use the white paper. Toughest part about using the white paper is that you then have to trim the edges of the decal exactly on the color lines, otherwise you will have a white border around the design because the substrate itself is white.
I print my decals on a cheap Epson C88+ ink jet printer (that's a great printer for under $100). Keep in mind that as they come out of the printer the decals are not water proof, let alone fuel proof. The smallest drop of water will dissolve the ink. They must be top coated!
The paper sellers will also have a clear topcoat spray. I started out using that, but it wasn't fuel proof, so I'd then spray clear dope on top of that. I finally eliminated their top coat spray all together and now just spray the decals with 2 coats of Sig Lite-Coat Clear Dope. The dope goes on perfectly. I let the decal dry overnight after it comes out of the printer. Then spray on the first coat of dope and let it dry to the touch. Then the 2nd coat of dope and let it dry overnight. Then just dip the decal in room temperature water and apply to the model.
If a dope finish is being used on the model, let the decal dry on the airplane for a day or two and then shoot your final clear coats over the whole airplane.
One issue with ink jet decals is longevity. The inks have traditionally been very susceptible to fading from UV. That is getting better all the time. They now have special UV resistant inks you can buy that are supposed to be good for 100 years, but I haven't taken that step yet. Some of them will only work with special high priced photo printers. The good news is that most printer manufacturers are constantly improving their standard inks too. The Epson ink that I use in my C88+ is their new DuraBrite Ultra ink, which is supposed to have a lot longer life than any of my model airplanes ever last.
Here is a picture of some ink jet decals I recently made and applied to an RC ARF P-51 Mustang.
Mike Gretz