Small question about acrylic undercoat for oil paints

[Odi.et.amo]

Hello once again guys,
first let me say a big thank you to all who took care of me here and answered my question. It really means a lot for me! My order of Umton paints and accessories is on the way right now and I can't wait to get my hands on them.
But there is one more question before I'll dig in. I will be using acrylics as an udercoat (or underpainting) for oil paints. I've chosen Vallejo since they're available in lot of shops in Czech republic. But!... I have quiet a lot of Citadel paints at my disposal and I'm wondering if they would be good for this task. I know most of Citadel paint have semi gloss finish, but from what I've observed their Foundation line is matt. Underpainting requires matt finish so it is absorbant for oils. Have anyone tried this? Because if the Citadel paint would work for this that means more money for figures

 

[Tecumsea]

Hi Ivo, the foundation range are fine for undercoating as are the Vallejo (with a spot of Tamiya X21 flat base) on resin figures. If you are using metal figures the same applies but make sure you prime them first.

Keith

 

[Odi.et.amo]

Thank you that's great news. I just forgot to say I'll prime my miniatures anyway with spray primer or Vallejo polyurethane prime and the I'll paint on the acrylics followed by oils. I think I used wrong words (that's just me) Sorry about that.

 

[steve j]

hi ivo hope i'm not too late if your painting metal figures vellejo primer isn't very good it dosen't seem to stick to the metal very well

 

[Odi.et.amo]

Hi Steve
to be honest i didn't try to paint any metal miniature yet, but thank you for the info. I found that the Vallejo polyurethane primer is made more for an airbrush which I don't own and I'm not planning to get it in near future. From what I've done, it doestn't cover on completely on the first go with standart paintbrush (only tried on plastic minis so far). I wish I could get some of the Reaper's brush on primer, but I am not able to find it anywhere. Battlefield Berlin is now selling some of the Reaper range, but no primer. There is also an option to get Mr.Surfacer primer, but they recommend this for airbrush as well, so all in all I'm kinda screwed here One person on CZ forum suggested I could use some kind of enamel paint as a primer, but the thing is I taking this as the worst case scenario option, because somehow I don't like enamel paints. If you have any suggestion please tell me

 

[Einion]

I'm not sure if you've seen any references but auto primers (from a spraycan) are widely used for priming models these days. They're cheap, strong and they bond really well to a wide variety of materials so they're ideal for modelling.

Einion

 

[theBaron]

I'll second Einion, I use automotive primer to prime metal, resin and styrene. I use Walmart's brand, having tried some of the other paint brands' primers, like Rustoleum and Krylon. My experience was that Rustoleum and Krylon tended to be a little thicker than I liked, compared to Walmart's store brand, and a can of Rustoleum didn't go as far as a can of Walmart's.

I have yet to try using Mr Surfacer, applied with an airbrush, though I'm keen to try it.

Prosit!
Brad

 

[Odi.et.amo]

Yup I've heard about these auto primers before and I may try them for sure. Problem is the weather. It's quiet cold nowadays and I have no place where I can prime. That is why I'm trying to find brush on primer. The weather will be better eventually so I may get my hand on the auto primers, but I must think ahead. Tamiya makes some surface primers as well, but from what I've seen so far, they're classified more as a filler than primer. I'm confused

 

[theBaron]

I do my painting in the cellar, the temperature there is around 60 F at this time of the year. It sometimes takes the coats a little longer to cure, but otherwise, I haven't noticed any ill effects. I usually let coats cure 24 hours, but sometimes only 8 (spray in the morning, go to work, and resume working with the piece that evening).

Prosit!
Brad

 

[Einion]

Yup I've heard about these auto primers before and I may try them for sure. Problem is the weather. It's quiet cold nowadays and I have no place where I can prime.

I have the same problem too, many of us have. If it's sub-zero where you are it isn't really practical to spray-prime something outdoors - you can do it, but it's risky. But you can spray primer indoors if you're careful and you have somewhere suitable.

If you use an acrylic car primer (as opposed to the "cellulose" type as they're called over here) the fumes are much less pronounced, and truly safer, so within reason you can safely prime indoors. To be cautious you would do the spraying in a room you won't be using for a couple of hours and that you can leave a window open to air it out.

Warming the can of primer is a good general tip when spraying, but it's more vital in cold weather. You want the can to at least be around room temperature during warmer months but having it actually warm to the touch should give superior results because it thins the paint (reduces the viscosity) and increases the pressure in the can. Both of these together give finer atomisation, yielding a smoother coat.

As long as you're spraying appropriately for the specific primer I can't imagine there is any spraycan primer that wouldn't benefit from the above tip.

Oh and you must shake the can at least as long as they say on the label! If it says shake for three minutes it means three minutes, not 'three minutes' And if you're spraying a lot you need to re-shake the can periodically during the priming session.

That is why I'm trying to find brush on primer.

I've had the same wish for many years, but bottom line is that brush-on primers can't really compete with the spray variety I'm afraid. In terms of what's easily available, even the very best brush primer is no match for primer from a spraycan in a couple of key ways.

Tamiya makes some surface primers as well, but from what I've seen so far, they're classified more as a filler than primer. I'm confused

I would recommend you steer clear of Tamiya primers unless they are your only option - similar to any hobby product that has an equivalent made for a larger market, the hobby product is usually much more expensive. The difference really can be very large, as much as four or five times more per ml.

I think filler-primers should be avoided for figures because they're specifically designed to fill imperfections in the surface... the fine detail found in many figure kits could be small enough for the primer to act on it like it was an imperfection

Einion