Getting Vallejo Primer to stick - Airfix kits...

[Ralf]

Hi Folks, 

This must be an easy ask but I'm stumped so here goes... 

 

Firstly we take an Airfix meat van roof, firstly 2 panels have been abraded with a fibreglass brush, then the left hand side is cleaned with CIF and the right hand side with Fairy, both using a toothbrush and warm water. So it goes:

 

CIF, CIF + Abrasion, nothing, nothing, Fairy + Abrasion, Fairy from Left to Right... 

 

 

Then we take our well shaken paint... 

 

 

 

Then we try and paint the inside of the van roof, thicker further away from the camera, thinner nearer the camera... 

 

 

 

While I was at it I found a part built (not by me) airfix mineral sat on the work bench so the left hand side was treated with paint and the right hand side was thinned down. 

 

 

 

As you can see none of the painting is anywhere like satisfactory, so what am I doing wrong / not doing? 

 

 

Frustrated of Derby (aka Ralf) 

ps I've tried some Citadel Blue (no idea which shade) as well with very similar results, so I don't think it's the paint... 

 

 

Edited February 28, 2022 by Ralf
Pic in the wrong place!

[Quarryscapes]

59 minutes ago, Ralf said:

 

so what am I doing wrong

 

 

Painting with a brush. This stuff is meant for Airbrushing. If you need to use a brush, then you will need to build up in lots o very thin coats.

 

Look at the Model Color range if you intend to brush paint, they are a completely different consistency designed for brush application. 

[Les Bird]

If you have no problem using an aerosol, I can thoroughly recommend Tamiya fine surface primer. it covers well but doesn't obscure fine detail. By the way, a lot of washing up liquids leave behind a film which is supposed to stop food items clinging to the surface. so it will probably fend off paint too.

[Ralf]

16 hours ago, Quarryscapes said:

Painting with a brush.

 

Thank you @Quarryscapes, much appreciated I'm glad it's simply the wrong paint and not technique / surface prep.

 

The model colour range doesn't seem to have the primers included. They do Hobby Surface Primers which look like the Model Colour range but it simply says "Surface Primer can be used directly or diluted with Vallejo Airbrush Thinner of Flow Improver." so I assume they are spray only? 

 

https://acrylicosvallejo.com/en/category/hobby/surface-primer-en/

 

 

 

15 hours ago, Les Bird said:

If you have no problem using an aerosol, I can thoroughly recommend Tamiya fine surface primer.

 

Thanks Les, I vaguely do I don't enjoy it, uncomfortable and it never looks great but thats based on usually doing bigger flatter things than a 4mm wagon kit. Will try and find some brushable primer but keep the Tamiya in mind. 

 

Cheers

Ralf

[fulton]

Halfords aerosol primer, white or grey are my go to primer, works very well for me, dries thin and smooth, I always apply out doors, seems to stick well to brass, plastic, card etc. only problem were resin castings where I had not cleaned the release agent off properly. Was disappointed with Ammo Mig one shot primer, what ever I seemed to do, thinning down, air pressure adjustment, the air brush blocked up in no time.

Edited March 1, 2022 by fulton
added more

[phixer64]

One thing ive recently learnt is to lightly wash the all the plastic in soapy water and let to dry. This would get rid of the release agent that's present on all makes of plastic moulding. A friend told me about this, and he's a very competent miniature modeller.

I've actually tried this process, and yes it works. I work with Vallejo Paints with all of modelling. And use an airbrush, low PSI, very coats.

 

Regards Jeff

 

[Jeff Smith]

Firstly I only use primer on metal kits, usually rattle-can grey or black solvent types.

 

I don't generally clean plastic kit parts and have never had a problem with adherence, however Vallejo model color are not my favourite paints.  They are sometimes too thick and do not pass the thumbnail scratch test.  Humbrol and Testor acrylics are much tougher and more scratch resistant.  I have no experience with Vallejo Model Air paints as I don't use an airbrush.

 

It is a puzzle to me that the Model Air and Model Color ranges are not identical......

[Mikkel]

19 hours ago, Ralf said:

The model colour range doesn't seem to have the primers included. They do Hobby Surface Primers which look like the Model Colour range but it simply says "Surface Primer can be used directly or diluted with Vallejo Airbrush Thinner of Flow Improver." so I assume they are spray only? 

 

https://acrylicosvallejo.com/en/category/hobby/surface-primer-en/

 

That part of the range can in principle be used for brush-on priming, I sometimes use the black one for figures during the coldest winter months when I can't spray prime outside.

 

However, in general and certainly for rolling stock, spray-can acrylic primer really does give you better results - also if like me you then brush paint  Vallejo acrylics on top (in multiple thin layers). This primer in particular works well for me:  https://www.hobbycraft.co.uk/plastikote-grey-twist-and-spray-primer-400ml/577327-1002

 

[Enterprisingwestern]

 

Citadel/Games Workshop Chaos Black and Skull White (or whatever they are currently called!) rattle cans are my go to primers, along with the Halfords range of plastic primers applied in thin coats as the pigmentation seems a bit heavier due to it not being modelling paint primarily.

Oh, and everything washed in either IPA or acetone, dish soap has all sorts of nasties not required on models.

 

Mike.

Edited March 2, 2022 by Enterprisingwestern
Afterthought.

[Simond]

A word for the unwary.  Don’t wash plastic models in acetone…

 

IPA should be fine.

[simonmcp]

Would an Ultrasonic bath be any good at removing the release agent?

[Enterprisingwestern]

19 minutes ago, Simond said:

A word for the unwary.  Don’t wash plastic models in acetone…

 

IPA should be fine.

 

That's why I put either or, but thanks for your clarification.

As with all such cleaning/stripping methods, test on a small area before committing the deed.

 

7 minutes ago, simonmcp said:

Would an Ultrasonic bath be any good at removing the release agent?

 

Depends what you put in it I would think, I don't know what is in the cleaning agents that are recommended for them.

I use liquid caustic soda, diluted, in mine when cleaning etched brass, then rinse under warm water and follow up with a dunk in IPA or acetone.

 

Mike.

[Barclay]

I have to admit I've never washed a plastic kit of any kind, ever. I always prime lightly with Halfords rattle cans and the results are always very good - excellent coverage and they can cover very lightly if used with care.

[sagaguy]

On 28/02/2022 at 19:05, Les Bird said:

If you have no problem using an aerosol, I can thoroughly recommend Tamiya fine surface primer. it covers well but doesn't obscure fine detail. By the way, a lot of washing up liquids leave behind a film which is supposed to stop food items clinging to the surface. so it will probably fend off paint too.

Yes,washing up liquid is a Lanolin based product which does leave a film to which paint won`t adhere to.

 

                                   Ray.

[ColinK]

I too have had problems with Vallejo surface primer - found it to be useless.

 

I now use Halfords rattle can primer as it works well, but have to be careful to avoid getting it on too thick.  I must try and get some Tamiya fine surface primer.

[phixer64]

20 hours ago, Jeff Smith said:

Firstly I only use primer on metal kits, usually rattle-can grey or black solvent types.

 

I don't generally clean plastic kit parts and have never had a problem with adherence, however Vallejo model color are not my favourite paints.  They are sometimes too thick and do not pass the thumbnail scratch test.  Humbrol and Testor acrylics are much tougher and more scratch resistant.  I have no experience with Vallejo Model Air paints as I don't use an airbrush.

 

It is a puzzle to me that the Model Air and Model Color ranges are not identical......

Model Air Paints are pre thinned .

 

Reagrads Jeff

 

[Jeff Smith]

1 hour ago, phixer64 said:

Model Air Paints are pre thinned .

 

Reagrads Jeff

 

Yes, I realise that, I was referring to the Model Color being too thick sometimes for brush painting.  Also my comment about the Air and Color ranges not being the same was because I looked for an Air version in the expectation of it being thinner but it was not in the range......

 

Also as we're talking Vallejo, fully dried paint is susceptible to IPA as used in some weathering washes.

[Wheatley]

Halford or Games Workshop Chaos Black / Coral White here too, it doesn't need a thick coat and it takes Vallejo Model Colour with no reaction. Model Colour does need a coat of matt varnish afterwards to stop it rubbing off though as it's not as hard-wearing as Tamiya acrylic or any enamel. I've never washed a plastic  kit with anything prior to painting.

Edited March 2, 2022 by Wheatley

[Steamport Southport]

15 hours ago, sagaguy said:

Yes,washing up liquid is a Lanolin based product which does leave a film to which paint won`t adhere to.

 

                                   Ray.

 

That's why you rinse it with water.....

 

 

It's the release agent you need to get rid of. Something that is far worse than a bit of Fairy Liquid and also the reason it was nearly impossible to paint Airfix and similar figures back in the day.

 

It's even printed in the instructions on recent Airfix kits.

 

 

 

Jason

[Enterprisingwestern]

6 hours ago, Steamport Southport said:

 

That's why you rinse it with water.....

 

 

It's the release agent you need to get rid of. Something that is far worse than a bit of Fairy Liquid and also the reason it was nearly impossible to paint Airfix and similar figures back in the day.

 

It's even printed in the instructions on recent Airfix kits.

 

 

 

Jason

 

Not being a chemist, but, I think there is quite a difference between the plastic  used in original Airfix kits as opposed to the bar of soap related plastic used by Dapol/faux Kitmaster kits of today.

Clarification of exactly which era of kit might help solve the problem.

 

Mike.

[sagaguy]

Dapol use grey recycled polystyrene which is softer than Kitmaster which in comparison is quite brittle. 

 

Ray

[Steamport Southport]

7 hours ago, Enterprisingwestern said:

 

Not being a chemist, but, I think there is quite a difference between the plastic  used in original Airfix kits as opposed to the bar of soap related plastic used by Dapol/faux Kitmaster kits of today.

Clarification of exactly which era of kit might help solve the problem.

 

Mike.

 

I never mentioned Dapol, but have never had a problem painting Dapol kits. Just as easy to paint as anything else.

 

I'm talking about Airfix kits as is the OP. He posted photos of them in first post and the other thread. 1970s era Airfix Meat Van kits.

 

 

Kitmaster never made wagon kits. They originated from Airfix.

 

 

 

But it's not the plastic it's the release agent that is the problem. Something plastic kit builders have known for decades.

 

 

From the instructions in a brand new Airfix kit. This one is a Cromwell tank.

 

FOR BEST RESULTS

Surfaces to be painted should be clean - before parts are removed from the sprue, wash in warm, soapy water, rinse and dry thoroughly. Stir paints thoroughly before use.

 

 

 

Anyone still having problems needs to start looking at what paint they are using. Try enamels. 

 

 

Jason

[Enterprisingwestern]

45 minutes ago, Steamport Southport said:

Kitmaster never made wagon kits. They originated from Airfix.

 

Pedantically (or matter of factly) they did, a motorised box van.

I was really referring to the current re-branding, but I think you knew that anyway.

 

Mike.

[Simond]

There is no release agent on injection moulded parts.  It’s not required.

Release agent is typically sprayed or hand-applied to moulds for lay-ups, fibreglass, carbon fibre, etc,.

 

the old Airfix soldiers of my youth were moulded from polythene, a material which has a very low surface energy, and is very difficult to paint for that reason.