Acrylic Primer advice

HighDesertmodeler

I usually lay down either Tamiya Lt Grey or NATO black thinned with Tamiya lacquer thinner as my primer.  I've had success then laying down water base acrylics over them using either Vallejo or MMP for my base coats and camo...never had a problem with the acrylics on a lacquer primed model, masking or otherwise.  

Recently I decided to us a water base acrylic primer (MMP Clear Primer).  I had it on for at least three days and when I was masking off panel lines for scribing, the tape (Tamiya) removed the MMP primer.  Very disappointed.  I had also prepared the model in my usual way cleaning it down with 91% Isopropy.

Lessons learned for me, stay away from water base primers unless folks out there can give me some advice using them?   I just think that lacquer based paints adhere much better to bare plastic...

Hope you can help,

Thank you, Eric

 

it's true that different types of primers and paints can have varying levels of adhesion and compatibility, there are a few things you can consider to improve your experience with water-based primers:

1. Surface Preparation: Just as you did with your lacquer primer, proper surface preparation is crucial when using water-based primers. Make sure the surface is clean, free from oils, dust, and residues. Cleaning the model with isopropyl alcohol is a good practice.

2. Primer Compatibility: Not all water-based primers are created equal. Different brands and formulations can have varying levels of adhesion. It's possible that the specific water-based primer you used might not have bonded well with the plastic or your lacquer-based paints. Experimenting with different water-based primers could yield better results.

3. Cure Time: Water-based acrylic primers can take longer to fully cure and bond compared to lacquer-based primers. Make sure to follow the manufacturer's recommended cure time before attempting to mask or handle the primed surface.

4. Adhesion Promoters: Some water-based primers might benefit from the use of adhesion promoters or surface primers designed to improve the bond between the primer and subsequent layers of paint. These can be especially helpful when working with tricky surfaces or different paint types.

5. Test and Practice: If you're considering using a new type of primer or paint, it's always a good idea to test it on a scrap piece or an inconspicuous area of your model before applying it to the entire model. This way, you can identify any potential issues before committing to the whole project.

6. Feedback from Modelers: Forums, online communities, and hobby groups can be valuable resources for learning from other modelers' experiences. You might find insights, tips, and recommendations on specific primer and paint combinations that work well together.

stikpusher

A good hobby shop was one of two requirements that I had for moving to a new area, as we did in 2020 when I retired. The other was an active IPMS or AMPS chapter. We have IPMS here and AMPS has started and is growing since the pandemic madness is over. There are several decent hobby shops in the greater Phoenix area.

 

We have one decent hobby shop, covering planes trains and automobiles. The model ship builders club is big there, same for railroad and RC aircraft. They stick pretty much hard line Testors and Tamiya for paints, things like Ammo or Valejo, Stynylrez are off their radar. And their pricing is a bit rough on the wallet. And then we have Hobby Lobby. It's a pretty common practice for me to order online, this last order was the first time I've had a paint cap loosen up though.

A good hobby shop was one of two requirements that I had for moving to a new area, as we did in 2020 when I retired. The other was an active IPMS or AMPS chapter. We have IPMS here and AMPS has started and is growing since the pandemic madness is over. There are several decent hobby shops in the greater Phoenix area.

stikpusher

 

I think if you research the Ammo primer a bit you will find it's rebadged Badger Stynylrez. A quick search on the internet will reveal this.

 

Thats what I've read/heard online. Most shops that I visit carry Ammo one shot, but none carry the Badger stuff, so that makes it easy. And I like the fact that it comes in multiple colors to suit your top color choice.

 

One thing, you're fortunate to have either one locally. That I do not have and order online. I just got some white in two days ago that leaked . Only lost maybe 1/8th inch of paint from the bottle but you can imagine the mess in the packaging. The bottle looks 10 years old now but the primer seems fine.  To have UPS pick it up is $7.99, to drop it off at the UPS store is a 13 mile drive one way. The company will swap it out but I'm not bothering.

oldermodelguy

 

 

stikpusher

I've been using Ammo One Shot primer when I need to use a primer and find that this stuff works great. No muss or fuss, and it comes in several colors to choose from. I don't know what its made from but once it's dried 24 hours or so, it performs flawlessly.

 

 

 

 

I think if you research the Ammo primer a bit you will find it's rebadged Badger Stynylrez. A quick search on the internet will reveal this.

 

Thats what I've read/heard online. Most shops that I visit carry Ammo one shot, but none carry the Badger stuff, so that makes it easy. And I like the fact that it comes in multiple colors to suit your top color choice.

oldermodelguy

 

the Baron

I should add a followup about the automotive primers.  I used Rustoleum, and WalMart's house brand.  They worked well as primers, though they're a little coarser than Tamiya's. 

I stopped using them because of a mechanical problem-both brands changed the type of nozzle on their cans, and I found that the nozzle and the opening on the can clogged consistently.  The nozzle can be soaked, but the opening at the neck of the can couldn't.

Apparently, though, Rustoleum has changed the type of nozzle again, and I may buy a can to see if the new type eliminates the issue. 

Both yesterday and today I was spraying Rustoleum on metal lawn furniture, expanded steal mesh type table and chairs. I used both the 2X and also the traditional old style white canned stuff. I had no issue spraying them down to empty fwiw. The only thing is I'm not done,the wife dug out some more metal pieces ( all this is satin or semigloss black) and I told her for what we have going on I'd have been better off buying a quart and spraying all this stuff with the compressor and my LVLP spray gun ! But the point of my reply is the spray cans did work fine. I'm not done and need more but they worked fine. And it's not as though I never went through the clogging era myself.

stikpusher

I've been using Ammo One Shot primer when I need to use a primer and find that this stuff works great. No muss or fuss, and it comes in several colors to choose from. I don't know what its made from but once it's dried 24 hours or so, it performs flawlessly.

 

I think if you research the Ammo primer a bit you will find it's rebadged Badger Stynylrez. A quick search on the internet will reveal this.

the Baron

I should add a followup about the automotive primers.  I used Rustoleum, and WalMart's house brand.  They worked well as primers, though they're a little coarser than Tamiya's. 

I stopped using them because of a mechanical problem-both brands changed the type of nozzle on their cans, and I found that the nozzle and the opening on the can clogged consistently.  The nozzle can be soaked, but the opening at the neck of the can couldn't.

Apparently, though, Rustoleum has changed the type of nozzle again, and I may buy a can to see if the new type eliminates the issue.

 

Both yesterday and today I was spraying Rustoleum on metal lawn furniture, expanded steal mesh type table and chairs. I used both the 2X and also the traditional old style white canned stuff. I had no issue spraying them down to empty fwiw. The only thing is I'm not done,the wife dug out some more metal pieces ( all this is satin or semigloss black) and I told her for what we have going on I'd have been better off buying a quart and spraying all this stuff with the compressor and my LVLP spray gun ! But the point of my reply is the spray cans did work fine. I'm not done and need more but they worked fine. And it's not as though I never went through the clogging era myself.

I've been using Ammo One Shot primer when I need to use a primer and find that this stuff works great. No muss or fuss, and it comes in several colors to choose from. I don't know what its made from but once it's dried 24 hours or so, it performs flawlessly.

I should add a followup about the automotive primers.  I used Rustoleum, and WalMart's house brand.  They worked well as primers, though they're a little coarser than Tamiya's. 

I stopped using them because of a mechanical problem-both brands changed the type of nozzle on their cans, and I found that the nozzle and the opening on the can clogged consistently.  The nozzle can be soaked, but the opening at the neck of the can couldn't.

Apparently, though, Rustoleum has changed the type of nozzle again, and I may buy a can to see if the new type eliminates the issue.

I use Tamiya's Fine Surface Primer, and I've used automotive primers in the past.  Lacquer-based and enamel primers chemically bond better to the surface than water-based acrylics.  Tamiya's X/XF line of acrylics can bond better than say, Vallejo's Model Color, or other water-based acrylics.  But I wouldn't expect them to work as well as primers.

I clean my sprues with warm water and a degreaser, too, before priming.  Some guys will use isopropyl to clean the surface. Whatever the cleaner, the point is to have as clean a surface as possible, before applying a primer.

And even with all that, you can still have tape lift off color and primer coats, too.

I've used Badger's 3D primer on the gantry of my Russian Kommuna salvage ship.  It has adhered well and has stood up well to sanding. It was a good base for some Colourcoat enamels.    I only bought it in Black, but may try mixing it with some Stynlyres White for the next prime job on the hull

Im also going to try some Scale Colors acrylic primer. Pick some up at the IPMS Nats.  Jeff sold out on the first day last year

Never used water-based acrylic primers.  Just never understood how that was supposed to work, since water has no etching capabilities with plastic.  I airbrush decanted Tamiya Surface Primer, thinned with MEK for extra bite on the plastic.  Preserves all the fine details and never peels away, even when trying to tear it off with Dymo tape.  That and Mr. Surfacer (which I think is pretty much the same stuff) sand and feather really well.  Decanting makes a single can of the stuff go a long way.

I use Stynylrez or Mr Primer Surfacer pretty much interchangeably. If the Stynylrez needs a bit of thinning for a smaller needle or I just want it thinner, lacquer thinner will work or my own alcohol based thinner I make up for acrylics works well too. Stynylrez has a strong bond, it's a poly resin acrylic primer. I've never had tape pull it up. And it sands well. I stock Stynylrez in white and black, I use the black also as flat black at times but also mix drops of black into the white to get whatever shad of grey I'm after. I also stock the Mr Primer Surfacer in grey for any hotter lacquers I may want to use ( rare for me to use hot lacquer though).

The Mr primers I generally shoot outdoors, where the Stynylrez I just shoot into a kitchen trash can with a liner in it. There is no odor in the house with Stynylrez and it has passed my blue painters tape pull test, same as Mr has. As I've mentioned in other threads, the only thing with Stynylrez is clean your airbrush the minute you're done spraying it. If it dries in your brush it's a bear to get out. Also don't let it freeze. And if it gets a lot of shelf time then use something like a Badger mixer, you will never get it all mixed back together with a stick if it happened to separate and really settled in that way. But the mixer is good to have anyway for any paint.

With all that said, the primers I don't care for are enamel based.

I used Tamiya fine surace primer or sometimes Gunze Mr Surfacer. I have heard great things about othere Gunze/mr hobby spray primers as well, though they seem a bit pricy... If using the above in spray can, make sure you warm up the can in a hot water bath until it feels warm in the hand (after shaking) for best results--if your workshop is cold (less than 70 degrees) you may want to use a hair dryer to warm up your model before spraying as well....

True,I have always used Tamiya or Mr Surfacer primers,some of those acrylic primers like Vallejo also don't sand well either.

Why should I change,they work and when I spray I go to the far side of my basement with a respirator,or go out on my walkout,never much exposure.