Dullcote, in the small spray cans, has been used for some time without adverse effect and without complaint. On the contrary, it has worked very well, thank you. It has been used to take the shine from model trains, specifically, HO German freight cars.
It usually worked fine with two coats, applied evenly, spaced three hours apart, outside in the shade where the average temperature and humidity are 75 and 50% respectively. The HO cars were then left in the direct sun to dry thoroughly. The cans are shaken for more than five minutes before application and the recommended distance was maintained.
September 2004 twelve cans of DullCote were obtained at the same hobby shop. At least two of the first four cans used produced a semi-gloss finish that refused to dull despite repeated applications. The remaining eight cans all worked as designed. Alas, 31 freight cars received the rotten Dull Cote.
After registering a call for help the engineering team at Testors became involved. Unfortunately, they were stumped with the problem and were unable to rectify the semi-gloss finish on the 31 cars despite weeks of tests with freight cars from the disastrous batch.
In lieu of coming up with anything substantial they did send three cans of an “enamel DullCote” for testing purposes along with a returned freight car that had been sent to them for testing purposes. The car that returned from Testors Engineering looked like it had been repeatedly sprayed/abused at a cheap auto-repainting franchise with a semi-clogged spray gun… all the detail was lost behind rounded hills of thick paint.
The 31-minus-1 cars have been relegated to the “heavily weathered” group of freight cars after hours and hours of rubbing… alcohol washes with India ink… etc. Strangely, they still have, beneath all that weathering, a semi-gloss finish that is all too apparent.
If you have ever come across a bad batch of DullCote what have you done to rectify the problem? If you have not experienced this failure, be certain to test each can/jar before offering your completed treasure(s) to the chancy Gods of DullCote spray.
I had a can do similar once… it produced a semi-gloss finish with ‘rivulets’ of dull mixed through it… I shook good for at least a minute before so I don’t think it was just not being mixed well that did it… bought another can and it worked fine and haven’t had the problem since…
I’ve never had that problem with Cullcote (The major problems I’ve had with it has to do with the application of it during periods of high humidity- but that’s an operator head space and timing problem). However, several years ago I read an article describing the use of artist’s spray fixative instead of Gloss Cote or Dull Cote (The particular fixative comes in flat, eggshell (semi-gloss) and Gloss). I picked up a couple of cans of which the first worked perfectly but the second varied from a semi-gloss to an almost Gloss each time I tried to use it. Never figured it out and never used the fixative again. Now I buy Dull Coat in the bottle and apply it with an airbrush.
Had a different problem with Glosscoat. It went on pretty blotching, almost ruined the model. After buffing it out, I just used MM Acryl Clear Gloss, decaled, and shot it with MM Acryl Clear Flat. Prety much saved the model, and about three months work!
Guess what, think I’ll stick with the Acryls form now on. Easy to air brush, nice results and easy clean-up. I use the High - Flo (yellow) nozzle for acrylics, with the usual cleaning as necessary.
I have had inconsistent results from Dull Coat. I’ve never used rattle cans but always bought it in a bottle fro use with my airbrush. The bottom line is that some bottles would produce a dead flat finish and others a satin, almost semi-gloss finish. I could find no rhyme nor reason for the variation in terms of thinning ratios, airbrush pressure, etc., so I concluded that it was a matter of batch to batch variation.
My solution was to switch to acrylic clear using Future flattened with Tamiya’s X-21 Flat base at a 4:1 ratio. I’ve done a few models with it and am pleased. Alternatively, I’ve heard high recommendations for Polyscale’s clear flat.