Fixer trouble

Although I have been modelling for a while, I have only recently started weathering. I am using mig pigments, which have been recomended by several friends and I am building a tank at the moment. Remembering my army days and how filthy our vehicles always looked when we came off an exercise I am trying to create that look using various pigment mixtures focused around MIG dry mud. I am quite pleased with the effects of dry brushing but this is where my problems begin.

If I brush on the pigment and leave it, it comes off and creates a mess (Much to the displeasure of my better half).

If I put the pigment on followed by MIG fixer it dries several shades darker and I am cursed with dry water type marks.

If I apply the MIG fixer followed by the pigment I still frequently have a problem with drying marks and some of the pigment comes off.

Does anyone have a solution, especially around the drying marks. They are driving me nuts.

FYO I have used in this order 1) humbrol enamel paint, 2) Johnsons clear, 3) a modelling wash, 4) pigment/fixer and fixer/pigment.

Many thanks for any suggestions

If you have an airbrush you can use my decal sealer. Mist it on lightly.

Or you can use any of the aerosol fixatives found at the craft store, again light misting coats. All you need is a very fine amount to latch on and hold the pigments in place.

I’ve only recently started using MIG pigments (MUCH better than Doc O’Brien weathering powders, by the way), and I’ve had great success fixing them by dabbing them with Mona Lisa Odorless Thinner (you can get it at Hobby Lobby in the art section).

No color change or drying marks, and it holds the pigments in place when applying clear coats (where the O’Brien powders lift and clump together).