etch priming with external mix airbrush

[chris251]

I've got some Pheonix Precision etch primer, and I'm looking to apply it with an airbrush to a brass model I've made.
The etch primer is a 2-part system, and it says on the instructions not to use an external mixing airbrush, but instead to use a badger 200 (without explaining which badger 200 - there's about 5 different ones available, and 3 nozzle sizes for each). I don't have a badger 200, and they're quite expensive at about £80 each, and I can only find them for sale with the medium or fine nozzle&needle combination, and to buy another nozzle and needle as well the airbrush looks as if it would cost about £110. Pheonix Precision did say over the phone that they meant a syphone feed one, but that's the only clue they gave me.

 

I tried applying it with my cheapo syphon-feed dual-action airbrush (with 0.5mm needle&nozzle) but it just clogged and would not work, so I ended up using my cheapo external mix airbrush, which did work, and the primer did stick well, and passes the finger-nail test. I'm definitely not using etch primer in my nice new Iwatta Neo gravity-feed airbrush!

 

Is there some reason why not to use an external mix airbrush for etch primer.

People seem to suggest a cheap airbrush for etch primer, but which one? would I do better at looking at a different primer, someone suggested here on another question on rmweb about Hammerite Special metals primer, would this be better?

[PatB]

I did try etch primer (a hardware store rather than model variety) in an ultra-cheap external mix airbrush, bough primarily for the purpose. I just couldn't find a combination of degree of thinning and extent of stirring that would spray satisfactorily. I either ended up with, effectively, dirty thinners, or an airbrush clogged with long strings of viscous goo. Eventually I gave up and went back to car shop rattle-cans, which always seem to work well. 

[PaulCheffus]

Hi

 

I use one of these for spraying my Phoenix Precision etch primer but I am using the single pack type.

 

https://www.rdgtools.co.uk/acatalog/BD-132-Professional-Double-Action-Airbrush--gravity-feed--1685.html

 

I also swapped the needle for a 0.5mm version but they don’t seem to stock them anymore.

 

 

Cheers

 

Paul

[Torper]

Rather than mess around with two-part primers, good though they may be, try a rattle can of U-Pol Acid 8 Etch Primer, available from Halfords and others.  I've found it truly excellent, giving a perfect smooth finish, though care has to be taken not to spray it too heavily.  Once that's down I use the airbrush for everything else.  However, U-Pol has to be used as a primer on bare metal - try it on top of existing paint and the result is quite likely to be a rather nasty reaction.

 

Incidentally, when I bought my compressor from RDG Tools several years ago a couple of cheapo airbrushes came with it as part of the deal.  One of them was a BD-134 which looks exactly the same as the one Paul refers to above.  I tried it the other day when spraying some Precision varnish with which I didn't want tio risk my expnsive airbrushes and, to my suprise, found it to be a very competent performer that did a very good job.

 

DT

[ROSSPOP]

Also, rather than mess about with Precision two part primer and a Badger 200 both of which I`ve got....a rattle can of Closterman black etch primer( also available in grey) is an excellent product for 4mm and 7mm models ( now supplied by Advanced Paints).  Highly recommended.   I use this method all the time nowadays.

 

 

 

 

 

...and you don`t need a further black top coat for painting chassis....

[PatB]

1 hour ago, ROSSPOP said:

Also, rather than mess about with Precision two part primer and a Badger 200 both of which I`ve got....a rattle can of Closterman black etch primer( also available in grey) is an excellent product for 4mm and 7mm models ( now supplied by Advanced Paints).  Highly recommended.   I use this method all the time nowadays.

 

 

 

 

 

...and you don`t need a further black top coat for painting chassis....

Hmm. That appeals strongly to my lazy nature. I shall have to see if a similar product is available over here. 

[chris251]

That primer sounds promising, but I think I will try mixing up some of the 2 part primer (I will thin it quite thin with cellulose thinners) and then airbrush it with my cheap gravity-feed airbrush. I do have one like Paul is referring to, but I think I will try the 0.5mm needle and nozzle in my simpler gravity feed airbrush - it's easier to clean out than the side-feed one. I was previously reluctant to use said airbrush for primer as it was my best, but having got the Iwatta Neo now, I don't see why not use the cheap one for primer.

[ROSSPOP]

Tis very very promising.......................

 

Can be brush painted.......................................

 

 

which I had to do with this chassis today as I could`nt remove the hornblocks or the plunger pickups and masking is such a fag job.......

 

 

Plus....... It is such a fine paint that I was able to etch prime the whole cylinder block with rods and pistons in situ with just some minimal scraping away at the back of the slide bars to get things freely working.

 

 

 

As for the superstructure...... you `ve got to really clumsy to swamp it all with too much paint.... such an easy afternoons work.

 

 

 

.......................................................................................  Clostermann   Rules !! ...........................................................................................................................................

 

 

 

 

[chris251]

To brush paint that primer, do you need to buy it as a tin of primer as well?

Is there an expiry date for when it no longer works by? (pheonix precision 2 part primer has an expiry of a year or two)

 

Hopefully it will be cool enough tomorrow morning to airbrush primer, I've no intention of airbrushing primer when it's 24 or more degrees outside.

[ROSSPOP]

Just now, chris251 said:

To brush paint that primer, do you need to buy it as a tin of primer as well?

Is there an expiry date for when it no longer works by? (pheonix precision 2 part primer has an expiry of a year or two)

 

Hopefully it will be cool enough tomorrow morning to airbrush primer, I've no intention of airbrushing primer when it's 24 or more degrees outside.

 

 

Hell no..... after you`ve shaken the can for 3 minutes plus...... just spray some into an old but clean lid

 

 

...........and away you go..... clean your brush with Acetone afterwards.

 

And no expiry date on the cans but make sure you up-end the can and clear the nozzle after every use.

 

The hotter the sunshine for spraying the better..

 

I have always been concerned about using decent airbrushes for etch primers because if you don`t clean them thoroughly they will get etched primed themselves.

[polybear]

9 hours ago, chris251 said:

 

Is there an expiry date for when it no longer works by? (pheonix precision 2 part primer has an expiry of a year or two)

 

 

The TDS for the Clostermann etch primer quotes a shelf like of 2 years when unopended (presumably an aerosol is always unopened, even when you've started using it?), in specified storage conditions (i.e. don't go storing it in your loft or fridge...)

@ROSSPOP Have you ever purchased the Clostermann etch primer in tins (not aerosols) and thinned it yourself - if so how did you get on, and any tips please?  It would work out much cheaper I think.

 

Edited July 31, 2020 by polybear

[ROSSPOP]

2 hours ago, polybear said:

 

The TDS for the Clostermann etch primer quotes a shelf like of 2 years when unopended (presumably an aerosol is always unopened, even when you've started using it?), in specified storage conditions (i.e. don't go storing it in your loft or fridge...)

@ROSSPOP Have you ever purchased the Clostermann etch primer in tins (not aerosols) and thinned it yourself - if so how did you get on, and any tips please?  It would work out much cheaper I think.

 

 

No Polybear I`ve never used the tin version. I don`t really make that many etched kits nowadays and would rather buy  fresh on demand to save on accumulated storage in an uninsulated shed.  I`m sure when supplied by Clostermann they were 500ml cans though......

[chris251]

Airbrushed the pheonix 2-part etch primer this morning with the cheap gravity-feed airbrush and 0.5mm needle&nozzle, it worked faultlessly. (I did thin the primer with a bit of extra cellulose thinners).

I presume there was a leaky seal or just too thick liquid for my cheapo syphon feed airbrush when I tried last time, but when thinned, it works well in the gravity feed.

Comparing it to what I airbrushed with the primer with an external mix airbrush, it has a much better finish to that.

 

I'll post some pictures soon to illustrate. - I tried to get some photos but they didn't show the difference in finish, too grainy, but noticeable to the eye.

 

(When I run out of pheonix precision etch primer, I'll have to think what primer to go for, the black spray can primer sounds good for chassis work cos I don't need black paint on top, but no point buying more now that what I've got works)

 

Edited August 16, 2020 by chris251