Jump to content
ARC Discussion Forums

Sign in to follow this  
jotter

Yet another Alclad question

Recommended Posts

All right guys what about this one:

I'm building a P-47 and I used Alclad gloss black primer and waited two days and then sprayed on some Alclad Aluminum and it went on okay but then to my horror segments of it started cracking, more like crinkling as if it were a mashed up section of aluminum foil... I sanded off the sections reprimed and sprayed again... same thing

What did I do wrong???

Share this post


Link to post
Share on other sites
All right guys what about this one:

I'm building a P-47 and I used Alclad gloss black primer and waited two days and then sprayed on some Alclad Aluminum and it went on okay but then to my horror segments of it started cracking, more like crinkling as if it were a mashed up section of aluminum foil... I sanded off the sections reprimed and sprayed again... same thing

What did I do wrong???

This may not be quite what you're aiming at, but try not to touch the alclad for about 15 minutes (at least) after application. Even light touching of apparently dry paint can lead to "aluminium foil like" crinkling. I'm not sure if this is what is causing your problems (a photo if you have it would be good) but it's one possibility.

Cheers

Jamie

Share this post


Link to post
Share on other sites

The reason the Alclad split is because the base primer is not cured. Alclad black primer is the pits....I'm not sure that stuff ever totally dries. The Alclad clear gloss and gray primers are wonderfull however and you'll never have problems using them as a base coat.

Jerry

Share this post


Link to post
Share on other sites

Adding to what Jerry said, Tamiya fine white primer works fine too. From what I've read you only

need the gloss black when doing a polished chrome finish.....not a lot of call for that on our subjects :)

Share this post


Link to post
Share on other sites

This same problem seems to be posted over and over again and the answer consistently appears to be, "Don't use the Alclad black primer." I know I never will.

Edited by David Walker

Share this post


Link to post
Share on other sites

I had the precise same problem, except it was after using Tamiya TS-14 and Alclad steel, which was reputed to be the foolproof method, except I apparently broke the rule...

Brian

Share this post


Link to post
Share on other sites

Alclad's black primer seems to yield very mixed results, with horror stories like yours being alarmingly common.

Oh, and instead of sanding the offending primer/Alclad to remove it, try 99% rubbing alcohol instead. The alcohol will remove any lacquers (Tamiya spray, Gunze Mr. Surfacer, Alclad...) without harming the plastic at all.

For your primer, try using Mr. Surfacer 1000 or 1200 thinned 50% with lacquer thinner and airbrushed on. After it's dry, smooth it out with a 3000 grit polishing cloth, clean with soap and water (not alcohol!) and spray your Alclad. I've done many NMFs using this method and it's never once failed me.

Cheers,

Tony

Share this post


Link to post
Share on other sites
Alclad's black primer seems to yield very mixed results, with horror stories like yours being alarmingly common.

Oh, and instead of sanding the offending primer/Alclad to remove it, try 99% rubbing alcohol instead. The alcohol will remove any lacquers (Tamiya spray, Gunze Mr. Surfacer, Alclad...) without harming the plastic at all.

For your primer, try using Mr. Surfacer 1000 or 1200 thinned 50% with lacquer thinner and airbrushed on. After it's dry, smooth it out with a 3000 grit polishing cloth, clean with soap and water (not alcohol!) and spray your Alclad. I've done many NMFs using this method and it's never once failed me.

Cheers,

Tony

Thanks I'll give it a try!

Share this post


Link to post
Share on other sites

I looked at some new Alclad bottles, today, and, I mean really looked. When Alclad 2 first started, we were told that an acrylic undercoat was the correct item, for all of the "standard" Alclads, with Chrome, and Stainless Steel, to go over (gloss black) enamels. If you look at Alclad bottles, only those two shades have a recommendation to use the Alclad primer, and, with the primer's ingredients including Butanol, MEK, Methyl Isobutyl Ketone, and Toluene, it, most definitely, is not an acrylic. If the primer is compatible with chrome and stainless steel, it can't, as far as I can see, be compatible with the other colours. Try Tamiya acrylic, as an undercoat, and see what happens; keep the Alclad undercoat for the "specials," at least that's what I'd do.

Edgar

Share this post


Link to post
Share on other sites
[snip] Try Tamiya acrylic, as an undercoat, and see what happens; [/snip]

Tamiya spray lacquers make great primers, but their bottled acrylics will crack if used under Alclad (ask me how I know! :thumbsup: )

Share this post


Link to post
Share on other sites

Personally, I don't like Tamiya paints, but I was trying to think worldwide. Here, I use an aerosol primer, designed for the plastic parts of cars. I've never had any problem, with that, and it's possible to smooth it down with Micromesh. Being acrylic, it's compatible with all of the main colours, leaving enamels for the specials.

Edgar

Share this post


Link to post
Share on other sites
with the primer's ingredients including Butanol, MEK, Methyl Isobutyl Ketone, and Toluene, it, most definitely, is not an acrylic.

Actually, a carbon-solvent-based paint can be an acrylic, as the gloss black automotive acrylic lacquer I use under Alclad contains most, if not all, of those. It simply isn't an aqueous acrylic. Acrylic describes the vehicle of the paint, which is an acrylic resin. This can be either aqueous (water, alcohol) OR carbon-solvent (lacquers, white spirits, ketones) based. It's just because so many model paints that are acrylic just happen to also be aqueous, it's become associated over time that acrylic equals aqueous, and that just isn't the case.

Share this post


Link to post
Share on other sites
Actually, a carbon-solvent-based paint can be an acrylic, as the gloss black automotive acrylic lacquer I use under Alclad contains most, if not all, of those. It simply isn't an aqueous acrylic. Acrylic describes the vehicle of the paint, which is an acrylic resin. This can be either aqueous (water, alcohol) OR carbon-solvent (lacquers, white spirits, ketones) based. It's just because so many model paints that are acrylic just happen to also be aqueous, it's become associated over time that acrylic equals aqueous, and that just isn't the case.

So (and apologies if this has been previously answered: if so could you pass a pointer?) is Future/Klear over the top of a dark primer* likely to have this effect on AC2?

TIA - Patrick

* Don't own gloss paint but do own an He70, a bottle of AC2 and was planning to Klear over matt dark grey for the base coat. Cautiously, from what is written here...

Share this post


Link to post
Share on other sites

Pat,

How are you planning to layer it? The Tools'n'Tips pinned thread "Paint Compatibility: Crackin' of Acryl" probably has your answer. I don't know, as I've never used Future as a clear coat. The other thing you have to worry about, is that not all aqueous paints are compatible with each other when layered, and can cause cracking, and not all carbon solvent paints (enamel thinners, lacquer thinners, white spirits, any odiferous paint thinner) are compatible as well. There's someone here that mentions and describes them as "hot" and "cold" paints, which I think (warning, could be completely bass-ackwards so take as gospel at your own risk) is in reference to the drying/setting/curing times, and that if you try and apply a "hot" paint over a "cold" paint either too soon or too heavily the first pass, the "hot" paint will soften the "cold" paint, and as the "hot" paint cures faster, the slower "cold" paint underneath will cause the top to buckle and fracture since the top has set, while the bottom is still setting, changing, and off-gassing. I'm often confused by latex vs. enamel vs. lacquer issues, as well. We need to just get a bunch of paint experten together and write the definitive article on model paint types, solvents, formulas, and compatibility, full of charts, lists, and common paint brand descriptions. lol

All I know is that the black acrylic enamel automotive paint I use (I said acrylic lacquer earlier, and that was wrong, though I do have acrylic lacquers, as well. Isn't chemistry fun?) dries nearly instantly to a glossy sheen, sands and polishes to a mirror shine, and is good for ALL natural metal finishes. lol

Share this post


Link to post
Share on other sites

Horrido,

Many thanks for that. Sobering and very welcome (for a start, I wouldn't have put half the effort am now going to, into thinking about the final matt coats on several models :()

Re the Alclad, the chocolate silver paper solution starts looking appealing again :)

Cheers!

Patrick

Share this post


Link to post
Share on other sites

Hey All,

I will be building an F-84 soon and want to use Alclad II (will be my first time). Swanny recommends using Krylon Gloss Black, has anyone tried this?

Seems like he gets good results with all variations of the Alclad II...

Thanks

Zack

Share this post


Link to post
Share on other sites
[snip] Krylon Gloss Black, has anyone tried this?[/snip]

Krylon Gloss black works great as a primer for Alclad, particularly the Polished Aluminum shade. Just make sure you let it dry for a minimum of 24 hours before laying down the Alclad. It also works better if decanted from the spray bomb, thinned a bit (10%) with lacquer thinner and airbrushed on.

I used Krylon to prime under the leading edges of the HC Panther under the Polished Aluminum (and yes I know they're not supposed to be quite so shiny, but I wanted to experiment!)

f9ftb_2.jpg

Cheers,

Tony

Share this post


Link to post
Share on other sites

Another Alclad2 - gloss black disaster story. Can't believe how often this happens ;) . I use Tamiya spraycan primer - bulletproof under Alclad :)

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...