Advice needed re primer. Please!!

[Waspie]

Just to be clear, I'm happy with my airbrush. Happy with the paints I use. But for the lie of me I don't get good results from my primer.
I use Vallejo Grey. It seems to get good reviews from other users as far as research on the interweb show.
Today, I decided to get to grips with it and dedicated a session of experimenting.
I started with a mix of 50/50 then slowly worked my way through the Ultra 2024 settings to see if there was a better setting than the dedicated 'Prime' setting. Setting 'I' gave the best result but still poor!!
Then I started adding more Vallejo airbrush thinner, only by one drop a time. Ending in 6 drops of primer to 9 drops of Vallejo thinning agent. All achieving similar results to my initial 50/50 mix!!!
I experimented with 15 psi up to 25psi getting the best results at around 20 psi but nothing like acceptable.

Any advice would be most grateful. I've attached a couple of images to show you the effect it is leaving. I used a previously painted piece from the previous kit simply to show the effect better on the darker surface.

[langy71]

I find that with Vallejo primer being a water based acrylic it tends to 'separate' and spatter like it has on your test pieces due to the water 'sitting' on the plastic instead of laying down in a nice even layer, even when using more thinners to thin it down, which usually ends up with me having to lay down more coats to get an even finish.. I know other folk have had success with acrylic primers, but for the life of me I can't get the same kind of results as they do...and I tend to find acrylic primers too soft and liable to scratch off with the slightest friction against it..

So with that in mind I tend to always use a 'chemical based' primer such as Tamiya's ultra fine or Halfords plastic primer, this will 'bite' into the surface and lay down properly, (it is also possible to decant these from a spray can into a smaller bottle for running through the airbrush.. just remember to flush the airbrush with Tamiya's lacquer thinners or cellulose thinners afterwards...
HTH... :thumb2:

[Waspie]

I find that with Vallejo primer being a water based acrylic it tends to 'separate' and spatter like it has on your test pieces due to the water 'sitting' on the plastic instead of laying down in a nice even layer, even when using more thinners to thin it down, which usually ends up with me having to lay down more coats to get an even finish.. I know other folk have had success with acrylic primers, but for the life of me I can't get the same kind of results as they do...and I tend to find acrylic primers too soft and liable to scratch off with the slightest friction against it..

So with that in mind I tend to always use a 'chemical based' primer such as Tamiya's ultra fine or Halfords plastic primer, this will 'bite' into the surface and lay down properly, (it is also possible to decant these from a spray can into a smaller bottle for running through the airbrush.. just remember to flush the airbrush with Tamiya's lacquer thinners or cellulose thinners afterwards...
HTH... :thumb2:

Thanks Chris. Will the Tamiya primer accept acrylic paints on top? On my past couple of kits I accepted the rubbish prime as the subsequent layers of topcoat seemed to hide the horrible look of the primer. The best result I had was with the Beetle!! More luck than anything!!

[langy71]

Yes mate, it's perfect for this job, just give it a good 24hrs to 'gas off/harden' and your good to go...I've used it straight from the spray can with light coats and never been disappointed with the results...

(it's better when decanted as you've got more control from the airbrush, but straight from the can is good enough)

[Waspie]

I may try another test tomorrow before giving up on it. With the Beetle I had a decent result but then I was using distilled water to thin out the primer. I'll give that a blast!!

[Tim Marlow]

I use Vallejo black primer as a base for my little blokes and don’t have issues with poor adhesion at all. However, I do give them a good bath in washing up liquid and scrub with a soft brush.
When spraying it I add a couple of drops of flow aid and dilute it with the proper Vallejo airbrush thinners to get it properly mobile. Goes on fine in my experience. Does look like your issue is surface tension though, so try a drop or two of flow aid in your mix.
Tamiya grey primer is excellent. However, I found the fine white didn’t adhere well for me, coming off like powdered chalk, and I really wish they did the grey in a bottle so I didn’t have to transfer it for airbrush use. Mr Surfacer primer doesn’t stick too well. Alclad grey is excellent.

[Waspie]

Thanks for that Tim, I don't have therefore use any flow aid so I'll order some to see if that does anything. I have a 200ml bottle of primer so wouldn't want to ditch it, (that'll be the tight Jock side of me coming through)!!
I'm about a week away from priming the external surface of the Sea King so have time in hand.

Edited bit.
Flow improver ordered - should arrive tomorrow!!!

[Mark1]

Tamiya grey rattle can for me too,never had any issues with it even when ive only left it about 20 mins to dry before painting over, the 3rd gen ak black primer isnt bad but tamiya adheres better.

[JR]

I threw away , yes threw away all my dammed Vallejo primer one day as had the same results as you. Now use AK 3RD gen and recently following advice from Dave Lovell @ use Mr Hobby .
Now actually enjoy using the AB again.

[Waspie]

I threw away , yes threw away all my dammed Vallejo primer one day as had the same results as you. Now use AK 3RD gen and recently following advice from Dave Lovell @ use Mr Hobby .
Now actually enjoy using the AB again.

Well, if the flow improver don't improve I dare say. (close your ears dad), I'll probably end up throwing the damn stuff too!!!
Have to give it every chance though!!!
The end is nigh!!!!!!

[JR]

There is only so much messing about and the cleaning you have to go through Doug, until you've had enough. I'd reached that point after trying One Shot, Vallejo Ak normal , adding various retarders, extenders, bats blood and anything that according to the experts worked.
Once I went over to Mr Hobby and Ak e3d gen as I said, now bliss.:smiling::nerd:. You know you want to.

[Tim Marlow]

Interesting John. The Mr Hobby primer I’ve got led to paint lifting when removing masking tape on the current build. Haven’t had that happen for a long time. Vallejo primer and finger grease don’t mix though. The model needs to be clean before you apply it.

[Dave Ward]

I use Vallejo Grey Primer - I dilute it around 50/50 with Gloucestershire tap water & spray at about 1.5bar ( 22psi ) through a 0.4 nozzle. Vallejo does seem to react more to surfaces that aren't clean, I generally clean sprues before starting assembly & If I've handled parts a lot, I use IPA to clean. Always allow the primer at least 24 hours to really set!
Dave