Getting pigment to stick

[Doggy]

I'm trying to apply some black pigment to a muzzle on a tank. 

I've already varnished it and underneath I have a chipping medium.

The pigment is not really sticking to the gun, some is but I'm struggling to build it up.

I can't use water because of the chipping fluid.

I'm wondering if I'm better off just painting the soot.

Any tips?

 

Thanks.

[pigsty]

The more matt your surface is, the better the pigments will stick.  Conversely, if you have anything on there that's not a matt finish, that'll make it harder.  Nonetheless I've found that you can apply chalk pastels (much the same thing, only cheaper) to a couple of coats of Klear and to Halfords Appliance White.  Your varnish may not be the problem but, while I'm not sure what your chipping fluid is, I'd bet it's repelling the pigments.

 

Personally I'd:

• do the soot last.  Paint chips less than people think, and a bit of chipped paint covered in recent muzzle staining is more authentic than fresh chips going through the staining

or

• use paint.  I've always found that pastels go on much paler than they seem on the stick, or even on the paper.  That's great, because you can add layers to deepen your colour, but I'd struggle to get enough on to make a convincing muzzle stain.  I always find that dry-brushed black, followed by dry-brushed dark brown, looks pretty OK.

[Doggy]

22 minutes ago, pigsty said:

The more matt your surface is, the better the pigments will stick.  Conversely, if you have anything on there that's not a matt finish, that'll make it harder.  Nonetheless I've found that you can apply chalk pastels (much the same thing, only cheaper) to a couple of coats of Klear and to Halfords Appliance White.  Your varnish may not be the problem but, while I'm not sure what your chipping fluid is, I'd bet it's repelling the pigments.

 

Personally I'd:

• do the soot last.  Paint chips less than people think, and a bit of chipped paint covered in recent muzzle staining is more authentic than fresh chips going through the staining

or

• use paint.  I've always found that pastels go on much paler than they seem on the stick, or even on the paper.  That's great, because you can add layers to deepen your colour, but I'd struggle to get enough on to make a convincing muzzle stain.  I always find that dry-brushed black, followed by dry-brushed dark brown, looks pretty OK.

Painting a light coat on the muzzle might be a plan. Possibly the pigment will stick to the matt paint? 

I was watching some videos on YouTube, apparently I need a fixer.

Thanks.

[alt-92]

On 9/18/2021 at 9:21 PM, Doggy said:

Possibly the pigment will stick to the matt paint? 

It needs something to grip on, and a matt paint or varnish has more 'texture' for lack of a better explanation. 

[Doggy]

On 9/26/2021 at 1:21 PM, alt-92 said:

It needs something to grip on, and a matt paint or varnish has more 'texture' for lack of a better explanation. 

I never realised you put it on matt paint, I thought it had to be varnished first. I'll try it on the next model before I varnish it.

[alt-92]

It's more a question of playing with the smoothness or roughness of a paint or varnish finish to get the desired result. 

You would get a different result with a satin finish, for instance.  
 

[Ray_W]

Additional to what others have said, you can apply the pigments to a naphtha (lighter fluid) or odourless thinners base to act as a fixer. Does change the colour somewhat but will dry lighter than the following samples. The pigment is AK "Track Rust" in all cases. Naptha drys fast. Odourless thinners more slowly.

 

 

Odourless thinners is what I use to build dirt, mud and rust effects. Allows you to build the pigments and increase the "stick" to the surface. Great for weathering tracks. Good for application to gloss surfaces.

 

The dry pigment application to a matt surface finish surface would be what I would be doing for a gun muzzle if in accordance with the reference material.

 

Ray

[Doggy]

10 hours ago, alt-92 said:

It's more a question of playing with the smoothness or roughness of a paint or varnish finish to get the desired result. 

You would get a different result with a satin finish, for instance.  
 

It's satin varnish I use at the moment but I'm thinking about buying matt varnish. I can't find the Vallejo matt but I see winsor and Newton is well thought of, maybe I'll try that. 

[Doggy]

7 hours ago, Ray_W said:

Additional to what others have said, you can apply the pigments to a naphtha (lighter fluid) or odourless thinners base to act as a fixer. Does change the colour somewhat but will dry lighter than the following samples. The pigment is AK "Track Rust" in all cases. Naptha drys fast. Odourless thinners more slowly.

 

 

Odourless thinners is what I use to build dirt, mud and rust effects. Allows you to build the pigments and increase the "stick" to the surface. Great for weathering tracks. Good for application to gloss surfaces.

 

The dry pigment application to a matt surface finish surface would be what I would be doing for a gun muzzle if in accordance with the reference material.

 

Ray

I have daler Rowney odourless already, I'll play around with that.

[Doggy]

It's getting an idea of what order to do what. Using a chipping medium adds another step in for me. 

Could I Matt varnish, use pigment then varnish again with satin?

[Ade H]

On 18/09/2021 at 19:10, Doggy said:

I'm trying to apply some black pigment to a muzzle on a tank. 

I've already varnished it and underneath I have a chipping medium.

The pigment is not really sticking to the gun, some is but I'm struggling to build it up.

I can't use water because of the chipping fluid.

I'm wondering if I'm better off just painting the soot.

Any tips?

 

Thanks.

Hi Doggy. Can I bung a couple of questions and thoughts at you?

Do you know for sure that this gun barrel should have soot on it? (I know this may be too late now, but maybe it will help in future). I can't say that it never happened (that's like "no crew chief would ever...") but it's my understanding from other sources that the whole soot on the muzzle thing is wrong because tank ammo charges are smokeless. Maybe OK for a WW1 tank?

Second, do you need to varnish? If not, don't. Mainly, but not solely, because you cover all the variations in sheen which help to make stuff look real. Definitely don't varnish over pigments, unless you know what you're doing for some specific effect, because it tends to kill their appearance. The only things which we really do over pigments are oil paint rendering (OPR), wet effects, speckles, mud splashes, and of course more pigments.

Finally, how are you trying to apply your pigment? If you want a dry scrub, that needs tooth from the surface texture. That can be done with a cotton bud if a brush isn't working it in well enough. But most of my pigment work is done in suspensions (either spirit-based or water-based) and worked rather like a wash. There are many methods, though; even airbrushing.

For soot (when it's actually needed) I'd mix black oil (leached out a little first) with black pigment and a little thinner, then apply it as OPR.

Hope that helps a bit.

[Doggy]

On 10/3/2021 at 11:53 AM, Ade H said:

Hi Doggy. Can I bung a couple of questions and thoughts at you?

Do you know for sure that this gun barrel should have soot on it? (I know this may be too late now, but maybe it will help in future). I can't say that it never happened (that's like "no crew chief would ever...") but it's my understanding from other sources that the whole soot on the muzzle thing is wrong because tank ammo charges are smokeless. Maybe OK for a WW1 tank?

Second, do you need to varnish? If not, don't. Mainly, but not solely, because you cover all the variations in sheen which help to make stuff look real. Definitely don't varnish over pigments, unless you know what you're doing for some specific effect, because it tends to kill their appearance. The only things which we really do over pigments are oil paint rendering (OPR), wet effects, speckles, mud splashes, and of course more pigments.

Finally, how are you trying to apply your pigment? If you want a dry scrub, that needs tooth from the surface texture. That can be done with a cotton bud if a brush isn't working it in well enough. But most of my pigment work is done in suspensions (either spirit-based or water-based) and worked rather like a wash. There are many methods, though; even airbrushing.

For soot (when it's actually needed) I'd mix black oil (leached out a little first) with black pigment and a little thinner, then apply it as OPR.

Hope that helps a bit.

I never knew that about muzzle soot, I just assumed from looking at other models it would have soot, it looks good but I'll leave it off going forward.

 

I was just dry brushing the pigment on and sometimes it looks ok some times it looks terrible.

Watching Andy's hobby headquarters on YouTube he recommended a Vallejo wash on the tracks then apply pigment when it's still wet. It works as a fixer but the colour of the wash is lost in the pigment. So as you suggested I'll try a thinner as the fixer. I have x20a, Vallejo airbrush thinner and a daler Rowney thinner I use for oil washes.

 

Now I have seen soot coming out of exhausts and I'm struggling to make that look realistic too.

I was watching white tiger and the exhausts on the t34 had plenty of shiny soot due to engine oil being exhausted at the same time. Some shiny soot would be good around the exhausts.

 

If you have any more recommendations for me I'm all ears.

 

Thanks.

[Ade H]

Don't use only thinner unless it contains a binder (e.g. Vallejo Airbrush Thinner) or at least makes a chemical reaction with the paint below (and that obviously won't fix any more than a very thin layer of pigment).

 

My typical spirit-based mix is in the region of 2:1 odourless thinner to fixer, though that may go up to about 3:1 or down to 1:1 as needed and it quite often has a little oil paint added if I'm speckling it. For a water-based mixture, I use Vallejo thinner with distilled water and a surfactant (flow improver works). The Vallejo thinner is a strong binder, so it needs some dilution. You can also make a thick high-volume pigment mixture with Vallejo pigment binder or diluted matte Mod Podge.

 

With a little practice, you can know automatically what ratio or product to use for each pigment effect. For example, applying it as a wash for dust and blending it away when dry needs less binder; when building up layers of mud splashes, you can use more binder. If you want to layer dust washes, you can switch between water- and spirit-based mixes to minimise adverse effects on the layer below.

 

You can also dry drop pigments from a soft brush (tap the brush just off the surface) and fix that from a pipette or by spitting a fixer mix through an airbrush with the MAC valve nearly closed. Just mist the fixer over it without aiming directly at the pigment and use a piece of card to cover the rest of the model. I don't know if the following tip works for every airbrush, but my Iwata can replicate this effect by removing the air cap and using very low pressure.

 

Dry-brushing pigment is certainly doable, but it's about the hardest and least precisely controllable method for most uses. It can, as you found, look pretty awful when it gets away from you.

 

For exhaust soot and stains, you can airbrush matted paint (add a matte medium or ultra-matte varnish) or a pigment and Vallejo thinner mixture, and/or use OPR. OPR is my go-to for many weathering effects and you can include some pigments in it as well (great for rust effects). For oil coming out in exhaust, use OPR with pigments and don't leech the oil from the paint to keep it glossy. With care, you will be able to mix glossy and matte elements for a varied look.

 

And generally speaking, I wouldn't take my weathering inspiration from Andy Klein. He's a nice guy, but no Mike Rinaldi (to be fair, he wouldn't claim to be) and he has to build in his shop with limited spare time, which I think is why he keeps it basic.

 

P.S. Forgot to mention: when I make pigment suspension, I drop the pigments into a paint well, make up the fixer mix in another well, transfer just enough with a pipette (again, you can easily judge it with a little practice), and stir well with a brush. If oil is used, that goes in last and gets a throrough stir. That's the easiest way to mix all of the ingredients.

Edited November 13, 2021 by Ade H
corrected ratios