I bought a two pack of Walters HO scale potassium hydroxide cars earlier this year and I decided to weather them. I only got to do one so far. My preferred method is to rub oil pastels on the trucks and wheels and then follow that up with chalk pastel. I only weather car bodies with chalk pastel, however. I went out in the evening to dullcote the trucks and the carbody, and I got horrible crazing on the tank car body! I was NOT a happy camper. My hypothesis is that cooler temperatures cause this at random, as I have noticed it with knock off spray sealers as well. I just never thought it would happen with dullcote. I have used the same can on other projects with no problems at all, other than it also splatters instead of going on evenly, which is irritating but subtle enough, and it just looks like dried rain up close. In regards to my ruined tank car, the truck weathering turned out great (even though I used a knock off sealant for those) and I was able to mellow out the crazing on the tank car with some black chalk and oil pastel. Close call!
I’m curious why you would use the oil-based pastels on the trucks, but not on the car-body, too.
I use the oil-based ones only, and have had no issues with them coming off, either on their own or through handling. Even when applying airbrushed weathering, I never overcoat it with Dullcote, as it makes the weathering appear too uniform for my tastes.
If you want to avoid the spatter (and get more mileage than using spray-can Dullcote) airbrushing it will give more control and better coverage, without the spatters. I use it, usually 50/50, with lacquer thinner.
Here are some cars done with oil-based artists’ pastels, applied with a brush…
Accurail boxcar, with C-D-S dry transfer lettering…
…an Ertl r-t-r boxcar, a train show find…
…a modified Accurail Dominion/Fowler boxcar, with custom decal lettering from Rail Graphics…
For those not familiar with these pastels, they come in stick form, round or square, and paper-wrapped like a crayon. While you can buy them in sets, they’re also available singly, so you can simply pick out colours appropriate for the weathering you wish to represent - usually $.25-or-less per stick where I get them.
To use them, I rub them on some fairly-coarse sandpaper, then dump the resultant powder into a suitable container - the plastic bubble that’s used in conjunction with cardstock for packaging small items, such as Krazy Glue, works well.
Use a not-to-good brush, simply dipping it into the powder, then brush (or dump) it on the car, spreading it as needed, using either the brush or
Good Old #1260 Dullcote has been troublesome on tanks cars for me a couple of times. It tries to run and craze. I think the cylindrical body might have something to do with all this.
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Multiple light coats are your friend here. Also low humidity and a temperature arounf 60-75 dgrees seem to be best.
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-Kevin
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When you say it “crazed” the model, do you mean it attacked/melted the plastic (the usual meaning of “crazed” in modelling), or do you mean the model turned cloudy? If the latter, it’s a temperature and humidity issue. If you respray on a warm, dry day it should go away.
“Crazed” can also apply to the pre-existing paint film, and I’m almost certain this is the sense he meant.
By crazed I meant it put a white opaque seal down. Docterwayne, I think you might be confusing chalk pastels with oil pastels? In your post you said that you sanded your oil pastels. You can do that with CHALK pastels, but not oil pastels. Oil pastels are like crayons. They don’t sand well at all.[(-D]
White cloudiness in Dullcote can be caused by moisture in the air, or holding the can too far away from the model while spraying.
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Fortunately, it is pretty easy to fix most times.
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Let the offending coat fully dry, then give it another very light coat of Testors #1260 Dullcote, and it whill usually be OK.
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-Kevin
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Nope…no confusion…well, maybe some. I bought mine at an art supply store, and was told that they were oil-based pastels. However, I just now checked among the several types/brands, and some are shown as “soft pastels”, while others have no paper wrapper or have wrappers with nothing but the name of the colour. None are specificially labelled as oil-based pastels, though, so you may be correct.
However, when applied to my freight cars, they don’t wipe off easily, and once properly distributed with a brush, they neither flake-off nor can they be removed with a dry cloth. They also don’t result in fingerprints on the car, nor residue on my fingers, as might be likely with chalk.
I’ve not attempted to remove them with water, as that’s not been necessary, but perhaps I’ll try one and see if it comes off. If it does, I’d guess your supposition to be correct.
The sandpaper I use is usually #36 garnet paper - very coarse, and used with a fair bit of pressure…it’s close to the equivalent of a plane when working with wood. [:P]
Wayne
I use a brand called “Pan Pastels” I have not seen that behavior with Dullcote. I live in humid Maryland.
One humid night, almost foggy, I just went outside and sprayed dullcoat on a GP9 shell as part of routine weathering. I did not expect or plan for the clouding and additional weathering caused by the dullcoat, but immediately started trying to figure out how to undo it. But, I then decided that I liked the effect, particularly the way the engine now contrasted with its otherwise very similar consist mate.
I’m no stranger to Dull-Cote or other spray paints for use on models.
As mentioned earlier, there are three main factors that will affect the end result:
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The room (with air movement) should be at least 65 F and no higher than 90 F degrees.
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Humidity on the high side (say over 55 percent) can affect the application.
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The spray pattern should be light with maybe 3 or 4 passes. Remember, you start the pass before you get to the model and end it after you passed the model.
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This is true, and an often overlooked detail of using a spray can. If the room is too cold, the spray does not atomize as well when it passes through the nozzle.
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-Kevin
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