Notes on materials

Paints

In general, I'd like to send this message to the various manufacturers: There are people out there who still use a brush to apply paint; please make sure your paints contain enough pigment to cover a surface in a single coat! I can always thin down paint for airbrushing, but it's very hard to make it thicker for normal brushing. Don't tell me it's not possible, I have leftovers of twenty year old paints to prove it.

Revell Acrylics
No worse than others with a brush. Airbrushes well when thinned with alcohol. As with their enamels, white is yellow, and colour palette is not so great. Good stuff, if you happen to find the right colour.

Tamiya Acrylics
Useless with a brush, which is why I used to stay clear of acrylics. A second coat is almost always necessary, and this second coat will rip off parts of the first coat. Airbrushes well when thinned with alcohol. Limited palette, but useful colours, including some specifically Japanese colours you won't easily find elsewhere.
Special mention should be made of the clear, gloss varnish; very easy to get an even, high gloss coat with a normal brush, and a great base for decals. Looks like it might be just as good over transparencies as Future.The only item in the range I actually enjoy using.

Xtracrylics
Work well with brush or airbrush, but very hard to come by. When airbrushing, primer is mandatory unless you like disasters. Also, thinning with their own brand of thinner has been known to convert nice liquid paint into jucky paste (note: the thinner smelled alcoholic. I suspect this is the effect I describe for Humbrol in the gunk stage) Water works, but suface tension becomes a problem when airbrushing. Plain old alcohol or IPA?

Vallecho acrylics
Quite nice, even with a brush. Not sure I like the squeeze bottles it comes in though. Seems like I'll be wasting paint every time I use some, but on the other hand, I don't think I'll have many dried out jars of paint this way. Chemical composition varies between colours; some can be thinned for airbrushing (with either IPA or water, sometimes both, and only IPA works well), some are hopeless.

Humbrol acrylics
Use to be horrible, but seems to have improved considerably.
Generally a bit thick, handles well with a brush, and seems to be a tad slower than most of the others, which is a good thing to my mind. Never had much luck thinning acrylics with water for airbrushing, and these are no exception. IPA works well, but you need a lot of it, and you may have to ignore the point where the mixture seems to turn into useless gunk. Adding more IPA will fix this. My theory is that at first the IPA is a contaminant that reacts badly with the solvent and resin mixture, while at higher loadings the IPA actually displaces the water as solvent, and the whole lot becomes in effect IPA based paint harmlessly contaminated with a bit of water.

Revell enamels
Please bury these in the deepest hole you can find. Every few years, they change the media into something that will not mix in any way with anything but itself, and will react in creative way to anything but their propriatory, expensive thinner. Worst of all, this is the only model paint sold outside of specialist stores.

Humbroll enamels
Even with the gradual reduction in quality over the past thirty years, this is still my preferred range of paints. I have yet to find anything better, or with a wider range of colours.

Xtracolour
Certainly a match for Humbroll, but with a more specialised selection of colours. The two brand can even be mixed with a good chance of success. Difficult to find though.

Modelmaster enamel
Handles well on a brush, but some are very thick, almost paste like in consistency. Works perfectly in an airbrush, but can be a bit touchy about thinning ratios.

Modelmaster metalizer
Very, very thin paint, obviously intended for airbrush use. This makes sense, because in the hands of anyone but a true master, a normal brush is not going to produce a good natural metal finish anyway. Sprayed very lean under minimal pressure over gloss black, it works like the proverbial charm. Once the metallic coat is satisfactory, leave to dry for a bout a week and then spray on the propriatory sealant, and leave to dry again. I tried normal varnish, and though I got lucky once, it is asking for trouble.


Fillers


Decal solutions

Microscale
MicroSol works like a charm. It might not persuade a decal to lie down immediately, but if necessary you can drench a decal time and again until it surrenders. MicroSet, on the other hand, adds nothing but trouble. Plain old water seems almost as good when it comes to helping decals stick, but MicroSet can cause a verry messy interaction with the underlying paint. Be careful when using Microset on a kit that has Tamiya, and possibly other, acrylic paint on it; just sloshing it on may dissolv the paint as well.

Mr Mark
Whoa, this stuff is hot. The Setter component nearly dissolves decals all by itself. Maybe I should apply it more sparingly. The Softer component is stronger than MicroSol. No idea yet of the long term effects; a first kit has been treated with it, and will be kept under observation for some time.

Daco
Medium appears to be stronger than MicroSol, and can cause decals to become permanently wrinkled. More suited for thicker decals, I think. Haven't tried Strong yet.

Model Master
Seems about the same as MicroSol, but composition is different, according to my nose.


Glue (mostly solvents really)

Mobofix
How I wish this were still a relevant entry. The stuff that glued my childhood. Like everything else, it was declared carcinoginous and banned, but man, did it ever glue plastics.

Acetone
I experimented with this years ago, and it didn't work. Of course, that was in its incarnation as nail polish remover, which my mother was certain was just acetone. Recent tests with the real, undiluted stuff however, are quite different. Once every other effective solvent has inevitably gone the way of Mobofix and Tri, this will probably become my glue of choice. Very agressive, very thin.

Humbrol Liquid Poly
The best of the readily available glues. Good for slower jobs.

EMA plastic weld
Very thin, very fast. Ideal for just brushing over a seam and having it stick. Careful how you store it though, this stuff is volatile enough to vanish from tightly closed bottles intended for plastic glues. Decanting into old, easier to use Liquid Poly bottles is not going to work.

Plastruct plastic weld
Not to be confused with EMA's product by the same name. Also very thin, but just a tad slower. Good stuff.

Revell contacta liquid
One of the main reasons why I usually stay clear of Revell products. Way too thick and slow, and sticky to boot. Tries to be both solvent and actual glue, and fails at both. Note that this is based on tests at least a decade old. They may have changed the formula, but I was never interested in a rematch.

Stuff in tubes
I suppose it has the advantage of being gap filling, but if you use enough to fill a fair sized gap, you also use enough to dissolve most of your kit. Must have used buckets of Britfix and Uhu-plast in my early years, but wouldn't touch any of them with the proverbial ten foot pole these days.

CA
I'll use it for fast fitting of small parts, but that's about it. Don't like it very much. Grows brittle over the years, and although the thicker variants can fill gaps, they can also leave rock hard excess material on the kit, that is much harder to sand off than the surrounding plastic. Not my idea of fun.

Humbrol Clearfix
Intended for clear parts, but actually quite good for general purpose small fitting. Slow setting, but is dries up absolutely clear. If conditions allow, I use this rather than CA when fitting small parts, like things under wings.
UNTESTED: can apparently be thinned with neoprene glue (evo-stick, bison kit,..) solvent/thinner. The more obvious candidates apparently won't work.

Micro Kristal Klear
Similar in purpose to clearfix, this appears to be slightly better at spanning gaps in order to make windows, but less suited to use as glue.


Cheap chocolate/butter foil

Bare metal foil is well know for it's use in tricky masking work, but there's no real need to go out and buy it. The metal foil used in packaging chocolate or butter is typically made up of a paper inner layer, and a metal out one. Separate them, and the metal part will work as well as bare metal foils. With chocolate as a bonus, if that's your thing. Minor warning though: it doesn't stick to masking tape very well, so if you use both, put the foil on first.
I never could get the hang of removing the residue left behind by this kind of foil, so I'm now experimenting with alternatives.


Mould making/casting

Mould making tutorial written for UAMF

Silicone rubber
The material to use when making moulds. The trick is to get the catalist mixed through very thouroughly, otherwise you'll be looking a pockets of sticky paste in inconvenient spots in your mould. In a pinch, such spots could, if exposed, be fixed by dropping on some more catalist and stirring with a toothpick. Messy and ugly, but it can make the difference. Be very carefull when working with this stuff; the un-cured material is impossible to get out of anything, and the smallest smear of your fingers will spread out to do maximum damage.
In my opinion, the stated amounts of catalyst are usually too much, resulting in half cured rubber even before you're ready to cast the mould with it. Use less catalist, and you run increased risk non-curing rubber. Finicky business. I've also found that rubber that's been on the shelf for a long time needs even less catalyst.

Plasticene clay
No match for rubber, but very usefull for a quick and dirty copy. Squeeze original in, stick in the freezer for half an our, pick out original, and then pour in dental plaster. Obviously, this is good for open moulds only, but it's fast, and the results can have very sharp detail.

PU resin
Due to very short pot life, this has to be mixed and cast in no time flat, but the results are unbeatable. Not exactly easily available over the counter, and typically sold in amounts that are far too large for incidental use.

Just about any other resin
They all look great on the folder, but make the slightest error in mixing, or try to make anything too thin, and you'll end up with a mould full of resin that just won't set. Smelly, sticky, impossible to get rid of, and by now all through your carefully made mould and all over your tools, including fingers. Yuck.

Dental plaster
Almost as fast as PU resin, and very hard to get into a closed mould. If you can get it to work, the results are beautiful though. Has the benefits of being much easier to clean off, and if properly stored, near infinite shelf life.

Metal
Umpty different types of lead-tin alloys exist that are excellent for casting. Requires a slightly different mould design than resin, and your mould material must be able to take the heat. Not very forgiving to work with, and not as high resolution as resin, but castings that are stronger and can be bent/straightened rather than broken. Easiest recycling of failed castings ever.

Navigation trail: home » Notes on materials