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gman

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Posts posted by gman

  1. 24 minutes ago, Ace-Garageguy said:

    It's not so much "prefer" as it is what's correct.

    Exactly...and one of the reasons touching up real-car lacquer jobs (many factories used acrylic lacquer also) was so easy, as opposed to repairing enamel work. Did I mention I've been in the real-car repair/refinish/restoration/race prep business for well over 5 decades?

    Same kit, Duplicolor sandable gray primer, plastic crazed and significant swelling over the "peak" and emblem on the hood after they were sanded flat, allowed to dry thoroughly, and repeatedly re-primered and sanded until it was stable, then shot with Duplicolor color, as-shot, no clear, no color-sanding or polishing.

    "Acceptable"? Well, it's better than 99% of what I see on models, and illustrates that technique...including a thorough understanding of the materials and their limitations...is essential to produce "acceptable" results.

    AUG12014Caddy_Challenger_50olds077_zpsd04e6ca3.jpg

    AUG12014Caddy_Challenger_50olds079_zps80fcb570.jpg

    I wasn't referring to your work when I said "acceptable." That green looks great. I do not doubt your credentials, and I do admire your work and your posts, do appreciate what you have to say.

    I shot mine with a Duplicolor metallic brown over black primer, and my finish is what I was referring to as acceptable (as opposed to optimum). If my finish turned out like the hood on yours, I would have wrapped up the build at that point rather than shelving it. When I get around to it, mine will need additional colour coats and some paint correction.

    The statement I was making in my initial post in this thread is that there was likely still too much solvent in OP's primer which was trapped under the Testors and Tamiya he shot over top of it. Intention wise, I was trying to help the OP but I'll refrain from further posts in this thread as my intent isn't to argue with anyone.

  2. 18 hours ago, Ace-Garageguy said:

    No.

    Lacquers "cure" by evaporation of the solvents in them.

    Everything else you wrote is fine, but the above isn't.

    Lacquer solvents do indeed penetrate into some plastic substrates, some more than others, they definitely penetrate into any previous coats of material, and subsequent coats of material can indeed retard the evaporation of solvents in underlying coats...which can result in a surface that squirms around or expands unpredictably when topcoats are applied, leading to cracking or wrinkling that looks like the effect of lacquer shot over enamel.

    But as Duplicolor primers are, in general, much more solvent-resistant than any hobby primers, properly applied and aged Duplicolor primers should be fine under any hobby paint.

    Still, TESTING of any material combination you want to use ON PLASTIC THAT'S THE SAME AS THE MODEL YOU'RE TRYING TO PAINT, and applied and aged exactly the same way, is imperative to avoid problems like the OP had.

     

     

     

    What I am referring to with the statement "chemically bonding" to previous coats is that re-wetting, one coat of lacquer over another where the solvents activate the previous coat will then behave as one thicker coat rather than multiples.

    When you polish a paint job that consists of multiple coats of lacquer, it tends to be more homogenous (should you polish through one coat into the next) compared to polishing over multiple coats of enamel. Enamels never truly cure beyond the top skin of the paint layer, and wet sanding or polishing through the topmost layer can sometimes look like an archeological dig compared to using the same process on a lacquer paint job- changes in color as you go through that top skin into the uncured portion of enamel layers closer to the base styrene. 

    To be clear, I am not trying to be difficult or nitpick either. I like Duplicolor primers and paints and have used them under enamels (which I only use rarely now), under Duplicolor paint, and under Tamiya paint as well. All without issues. While sticking to a one product primer/basecoat/clearcoat system is much more predictable, I also use Tamiya and Gunze lacquer primers when the top coats are not going to contain hotter automotive solvents. If you prefer not using the word "cure" in relation to lacquers, that is fine...perhaps it would be better to say that all of the solvents have had a chance to evaporate or gas out rather than "cure." 

    Many years ago when I didn't know any better, I shot Duplicolor Wimbledon White straight over bare AMT styrene (no primer) on a '32 Ford. As you can expect, that didn't work out well and it caused a bunch of texture to poke out of the styrene resulting in a ruined finish. I resigned that body in the parts bin. I came across that body and pulled it out after a decade or so, and was surprised to see most of that texture had disappeared- I broke out some polish and had at it, and was able to level any remaining texture into what would be considered an acceptable paint job without cutting through the Duplicolor. In about the same time period, I had a similar failed paint experiment shooting Duplicolor over un-primed Revell styrene on a '29 Roadster pickup. This attempt also polished out after many years, even though it didn't have as much texture as it did blush to a dead flat finish. While adding more lacquer to either body would have had the solvents wet and reactivate the mess caused by reaction from the styrene, those original coats of Duplicolor had certainly become stable over time and did not react to the mild solvents in the polishing compound. I have learned since the early 80's and always use a suitable primer under automotive lacquer.

    About 12 years ago, I primed the then-new Revell '50 Olds in Duplicolor black primer (two mist coats and one heavier coat). This kit uses the reformulated styrene that is more sensitive to lacquer than vintage styrene. After a few days (when I could no longer smell solvent in the primer and it had settled into not having any texture) I dusted on a few mist coats of Duplicolor base coat followed by one wetter coat and again got some horrible texture from solvents leaching down to the styrene. This too eventually settled down and was polished into something acceptable, though I burned through the color coat in a few areas. If I had a do-over, I would have let that primer gas out for a few weeks before spraying color. The point being, technique is every bit as important as using compatible products from one manufacturer's paint range. I really miss the old Plastikote lacquer primer, as I never had any adverse effects with that under automotive lacquer, hobby lacquers or enamels. 

    • Like 1
  3. Duplicolor lacquer primer and paint is good stuff, but because the solvents are "hot" for styrene it has to be treated carefully when used on plastic models. Lacquers cure by chemically bonding to the coats underneath. If the primer coat is on the thin side, a heavy second coat can have the solvents get trapped and cause the underlying styrene to soften and react.

    You have to let the solvents gas out really well whether you are shooting multiple coats of primer or color coat over primer so those solvents don't activate the coats underneath and have those solvents penetrate the primer (barrier) coat and react with the styrene. If you dust on multiple coats of primer and allow plenty of time for the solvents to evaporate, the primer will better act as a barrier to prevent color coats from getting all of the way through.

    While Testors and Tamiya lacquers carry much "cooler" solvents better suited to styrene, if they are shot on too heavy too quickly, they can activate an automotive  primer that isn't quite finished gassing out to hold those hotter Duplicolor solvents under subsequent coats against the styrene rather than allowing them to completely gas out. 

    While I usually use an automotive lacquer primer when I am going to use an automotive lacquer color coat, for Testors and Tamiya paints I would use a Tamiya or Gunze primer (and still allow ample time for underlying coats to fully cure). There are many users who have successfully used Tamiya and Gunze hobby primers under automotive lacquer color coats too, but I would err on the side of caution when doing so i.e. very thin coats with ample time to flash.

    I have many failed paint experiments under my belt, and in my experience Duplicolor primer really does need lots of time to cure to properly protect a styrene model kit body. I suspect it was the Duplicolor solvents remaining in the primer layer that caused the reaction OP has gotten rather than any of the Testors or Tamiya solvents shot over top.

    • Like 3
  4. Yes, the cigarette foil is good stuff with many uses. I scratchbuilt a master for some '37 Ford bullet-style tail lights and cast them in resin years ago, and used the textured foil as reflectors epoxied onto the back of the lenses. It gave a nice sparkled texture when seen through the red lenses.

    Heating that type of foil with a lighter usually allows separating the paper from the foil- you want to let the flame lick the paper side until the paper just starts to pull away on a corner and then gently peel the paper back onto itself.

  5. 21 hours ago, Roadrunner said:

    I was already thinking white interior (actually an off-white) with black carpet and dash.

    Tamiya Racing White with an over coat of semi-gloss lacquer would look great in that role. 

    I agree that either of those greens would look very sharp. 

    • Like 1
  6. I have used metallics for interiors multiple times. One of my favourites was Testors' discontinued jet exhaust metalizer covered with semi gloss for a nice "not quite black" interior tone.

    If the 2 tone vinyl is what you are going for, Tamiya TS aerosol light + dark gunmetal might do the trick. Dusting on the color coats from a distance will probably be best. Hit them with semi-gloss lacquer afterwards and it will tone down the metallics for a more in-scale vinyl look.

    Screen Shot 2023-11-05 at 12.06.52 PM.png

    • Thanks 1
  7. 8 hours ago, Roadrunner said:

    I'll soon be starting a '32 Ford sedan, and things like the bar across the radiator front, needs to have mold parting lines sanded smooth, and of course this will also strip the chrome right off. So I'm looking for methods, short of sending the parts to a chroming shop, to allow me to do it myself.

    Are you talking about the spreader bar that goes between the front frame horns? If so, cut a section of aluminum tubing to fit, polish it and replace the kit part completely.

  8. I find something to appreciate about each of your model's evolutionary stages.

    Long before Revell brought out their modern versions of the '32, I appreciated the AMT with all of its quirks. While it certainly pigeon holes the type of build you can make "out of the box" with their choices of sectioned bodies on their '32 variants (something that became apparent after Revell nailed the body dimensions), if that is the style of vehicle you are planning on building it does it well. I have a few AMT '29 and '32 builds I did in my youth that I look back on building fondly, and seeing as mine did not survive I wouldn't mind taking another crack at them one day with the same kits. It is nice to live vicariously through your (re)build.

  9. 1) start with as many great reference photos of the subject you are building as possible (know your subject)

    2) think in terms of what you will need to create as many of those "not in the box" details as possible on your chosen kit

    3) collect as many materials as possible (aftermarket, repurposed bits and pieces, spare parts) that will help you replicate those details

    4) tackle your build and detailing in a methodical way that allows those extras to be added where they show and won't be messed up by building subsequent parts of the kit

     

    A good way to start is by mastering "box stock," and then you can get into adding basic details common to most vehicles, like spark plug wiring, hoses, labels, markings, correct colors as you learn about vehicles in general and the one you are building specifically. As you start to get proficient with those extra details, you can add more and improve kit parts to better replicate the subject. As someone else has mentioned, jumping in with too much extra detail right out of the gate is a good way to stall an otherwise complete-able project and discourage yourself in the process. Pick some extra details you'd like to add to a kit, get it across the finish line, and then think in terms of what else you can add to the next one as you start to learn about that next project and its 1:1 counterpart. Building models is an evolution, so don't expect to super detail one until you are both familiar with the subject and what you can add to the model that will look convincing.

    One thing I started doing early on was to buy two kits of a subject I was going to build- you can separate and break down parts molded together in the box into single components for detail painting and better realism. Examples of this would be shaving off pieces molded to the firewall and inner fenders like wiper and blower motors, relays, regulators and other underhood details and grafting in parts removed from your second kit after detail painting them. You can do the same with suspension and chassis pieces that were originally molded into one assembly in the box. Another would be breaking down interior or engine components into separate parts and painting them separately before gluing them back together. While I know that buying multiples gets expensive at today's kit prices, you can coax more detail out of a model by doing so. Once you've mastered that, you may find you can scratch build individual parts of the vehicle more convincingly out of styrene stock, metal stock or other materials you have laying around. A good example of this is to replace kit driveshafts with shaped and painted aluminum or brass tubing, and gluing the kit u-joints to your new, perfectly round driveshaft. You can do the same with shock absorbers.

  10. That may affect the clear styrene (which on a good day right out of the box can be more brittle than non-clear parts).

    Have you considered testing with something like Novus #2 plastic polish on an area that doesn't show? That may take the tint off and give you a better than box stock shine on the kit glass in one go.

  11. Enamels have a "re-coat" window- you spray, they (somewhat) cure to the point additional coats can be applied without adverse reactions. Don't confuse enamel curing time with actual drying time. Some enamels may take months and months to fully dry to the point they stand up to handling. 

    Is the primer an enamel? If so, I'd seek out a lacquer primer instead which can be over coated with enamel if you strongly feel you want to use enamels. A lacquer primer will truly dry and do so quickly, and will be able to stand up to the solvents in enamel paints and provide a good foundation.

  12. The issue was 100% corrected for the Del Ray. Early issues of the Nomad had too large an apron behind the bumper, requiring some re-engineering of the apron to get the front bumper in the proper position- I haven't had a re-issue of the Nomad in my hands to compare against the original issue.

    For someone who has both an early issue and the reissue, it would be interesting to see some photos illustrating the difference in front bumper parts.

  13. Wow. Looks like someone was paying attention in "classic Model A hot rod" school, and then went for bonus points in perfect execution of finishes. I love the green, love the flathead and the megaphone headers. Great job on this.

    • Thanks 1
  14. 10 hours ago, CabDriver said:

    I use that same airbrush, and I like them.  I can get decent quality finishes with mine, I think:

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    D95B3962-5982-47E9-9FE6-C6BEB24553B3.thumb.jpeg.04fffd9a39f7ac44f66781fa544a1a3e.jpeg

    15B3B4CE-CAA9-4D7F-AB8E-3B5176478D53.thumb.jpeg.f528334172980db56449bcc438e4edc8.jpeg

     

    I would buy that same airbrush with a better compressor, like this:


    https://www.amazon.com/Timbertech-Airbrush-Compressor-AS18-2-Decoration/dp/B07VSFZVRH/ref=sr_1_5?crid=EDZFMAKJPLSQ&keywords=airbrush+compressor&qid=1692043091&sprefix=airbrush+compressor%2Caps%2C140&sr=8-5

    In fact, that's exactly what I bought, and it works well for the majority of my projects...not the fanciest setup, but user friendly and not super expensive

    Why yes- yes you can ;) (I am familiar with your work)

    I have zero experience with the airbrush OP linked, so I thank you for weighing in. 

    I was thinking about upgrading my airbrush one day, not to replace the old trusty Paasche but to add an extra tool to the tool box. Unfortunately, the one calling to me is somewhat more expensive but I'm hoping the fan pattern does the trick for painting bodies.

    https://spraygunner.com/airbrush-kits/by-type/gravity-feed/gsi-creos-mr-airbrush-procon-boy-ps-290/

    While I won't pull the trigger on one immediately (more of a want vs need), there are a few users here on the forum who seem to like them. 

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