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crowe-t

Plastic Spoons for testing paint?

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Is there a specific type of plastic spoon for testing paint?  I picked up a bag of cheap white plastic spoons at a dollar store and sprayed some primer on them.  The primer comes right off if a finger nail touches them and the spoon is perfectly smooth underneath.  The spoons are the flexible plastic.  

Should I have gotten the harder, more brittle spoons? 

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7 minutes ago, crowe-t said:

Is there a specific type of plastic spoon for testing paint?  I picked up a bag of cheap white plastic spoons at a dollar store and sprayed some primer on them.  The primer comes right off if a finger nail touches them and the spoon is perfectly smooth underneath.  The spoons are the flexible plastic.  

Should I have gotten the harder, more brittle spoons? 

I never thought about the quality of the spoons before, but this is a very good point. The brand I use is Dixie that I got at the regular market. I'm sure there are others but I can vouch for the Dixie brand if that helps you out.   

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Maybe it would help if you scuffed up the spoons before painting, or even using primer also. I never use spoons myself as I pick out a color or colors and "shoot from the hip" and so far I've been doing pretty good with that method.

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13 minutes ago, crowe-t said:

Is there a specific type of plastic spoon for testing paint?  I picked up a bag of cheap white plastic spoons at a dollar store and sprayed some primer on them.  The primer comes right off if a finger nail touches them and the spoon is perfectly smooth underneath.  The spoons are the flexible plastic.  

Should I have gotten the harder, more brittle spoons? 

"Flexible" plastic is not styrene. If you MUST test on spoons, get the "harder" ones.

This points up the fallacy of testing on spoons I've been harping on for YEARS.

Plastic spoons are ALMOST NEVER MADE OF THE SAME STUFF AS MODELS, so trying to determine chemical compatibility is impossible with spoons.

ALL YOU CAN DO WITH SPOONS IS A COLOR TEST, and because of the spoons small area, you CAN NOT learn to spray paint on spoons.

 

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Although the plastic in the spoon might not be same as the styrene used in the kit, the spoon provides an excellent testing tool for paint compatibility. For example, if you want to use Brand X primer, Brand Y color coat, and Brand Z clear coat, spoons are the way to go. I'd rather see the cracking/crazing on a spoon instead of a model.

Just make sure you use the same procedures you would use on a model (washing, painting. sanding, etc.) on the spoon. One of the earlier comments mentioned how easily the paint scraped off the spoon...perhaps there was still some release agent on the spoon.

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37 minutes ago, BigTallDad said:

Although the plastic in the spoon might not be same as the styrene used in the kit, the spoon provides an excellent testing tool for paint compatibility. For example, if you want to use Brand X primer, Brand Y color coat, and Brand Z clear coat, spoons are the way to go. I'd rather see the cracking/crazing on a spoon instead of a model.

Just make sure you use the same procedures you would use on a model (washing, painting. sanding, etc.) on the spoon. One of the earlier comments mentioned how easily the paint scraped off the spoon...perhaps there was still some release agent on the spoon.

No.

The material the spoon is made of is IMPORTANT, and can be JUST AS IMPORTANT as INTERCOAT COMPATIBILITY.

FOR INSTANCE: IF the FLEXIBLE spoon the OP mentioned is POLYPROPYLENE, no conventional paint will stick to it without a SPECIAL CHEMICAL ADHESION PROMOTER that most modelers have never heard of and wouldn't get anyway..

IF that's the case, a primer or topcoat MIGHT wrinkle, when it would be fine on styrene.

A POORLY ADHERED BASECOAT OR PRIMER CAN CAUSE JUST EXACTLY THE SAME APPARENT EFFECT AS PAINT INCOMPATIBILITY.

By the same token, MANY STYRENE SPOONS ARE MUCH HARDER AND MORE CHEMICAL RESISTANT THAN THE CRAPP MODELS ARE MADE FROM THESE DAYS.

If that's the case with your "test", the primer and paint might work fine with spoons, but will craze a model horribly.

I know these things from direct first had experience...including almost 50 years in the high-end automotive and aircraft industries, where there are MANY different materials to pay attention to, and where doing something wrong can cost many hundreds of dollars in wasted material and maybe thousands in labor.

SO...if you want a MEANINGFUL test, do it on the backside of a part (that won't show) ON THE SPECIFIC MODEL YOU"RE WORKING ON.

 

 

 

 

Edited by Ace-Garageguy

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I have actually been doing my testing on the hood of a model. They are generally fairly easily to strip and clean if things don't go as planned.

I tried testing colors on spoons and gave up after the first try because of the poor results. Hard to tell what a large flat panel will look like when using a small round sample area on the spoon.

I now use the spoons to eat applesauce....with cinnamon! :D

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Without being/sounding like a BLAH_BLAH_BLAH_BLAH, Ace, just what did you DO in the aviation field you keep bringing up? My PROFESSIONAL curiosity continues to be piqued by your repeated comments.

While some good points were brought up about base material compatibility, hard plastic spoons are absolutely the way to go for COLOR TESTING if you want to see what the particular color will look like once out of its' vessel. When it comes time to test material compatibility, the model manufacturer was kind enough to supply you with all the test material you need.........sprue!

 

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29 minutes ago, MarvinGardens said:

When it comes time to test material compatibility, the model manufacturer was kind enough to supply you with all the test material you need.........sprue!

 

AND the bottom of interior tubs, the tops of chassis, and other "big" parts that won't be used or won't be seen in the finished build. (These are especially useful if you need to know if some particular paint will cover some particular color of plastic.)

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46 minutes ago, MarvinGardens said:

Without being/sounding like a BLAH_BLAH_BLAH_BLAH, Ace, just what did you DO in the aviation field you keep bringing up? My PROFESSIONAL curiosity continues to be piqued by your repeated comments.

While some good points were brought up about base material compatibility, hard plastic spoons are absolutely the way to go for COLOR TESTING if you want to see what the particular color will look like once out of its' vessel. When it comes time to test material compatibility, the model manufacturer was kind enough to supply you with all the test material you need.........sprue!

 

1) I spent years developing and implementing repair procedures for composite aircraft structures.

2) You can't get an accurate idea of a color by painting spoons. That's why we don't do color sprayouts for real cars on compound-curved panels 

3) If you'd experimented as extensively as I have (and paid attention) you would have noticed that materials DON'T ALWAYS BEHAVE THE SAME WAY ON SPRUE AS THEY DO ON BROAD FLAT PANELS. The surface of the sprue is often noticeably harder and more chemical resistant than the adjoining panels. A primer that will lay down just lovely on sprue will often attack and craze the panel it's attached to.

Edited by Ace-Garageguy

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2) Apparently you missed the entire premise of that answer involving sprue: It was NOT for a color test, it was to be used for a COMPATIBLITY test (refer back to SPOONS for color).

1) I have been in quite a bit of Aviation for the past 20 years (as it is my JOB), and I am well aware of repair procedures for most of the common composites (used in commercial as well as Sport aircraft structures). Most, if not ALL, chemicals used in that aspect WILL eat the weak 'polystyrene' our kits are made of (as quite a few of those chemicals are either MEK/MPK, Acetone, or Xylene/Toluene based). So, your comment, while valid when used in the pretext of use on styrene, is pretty much useless as you used it to describe what would be needed to get paint to stick to poly plastics. Since models aren't Poly, he likely won't encounter, nor need to encounter, these chemicals.

 

So, my (and others) reference to using hard styrene spoons for COLOR TEST stands, as well as using the styrene sprue for MATEIALS COMPATIBILITY.

Edited by MarvinGardens

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2 minutes ago, MarvinGardens said:

2) Apparently you missed the entire premise of that answer involving sprue: It was NOT for a color test, it was to be used for a COMPATIBLITY test (refer back to SPOONS for color).

1) I have been in quite a bit of Aviation for the past 20 years (as it is my JOB), and I am well aware of repair procedures for most f the common composites (used in commercial as well as Sport aircraft structures). Most, if not ALL, chemicals used in that aspect WILL eat the weak 'polystyrene' our kits are made of (as quite a few of those chemicals are either MEK/MPK, Acetone, or Xylene/Toluene based). So, your comment, while valid when used in the pretext of use on styrene, is pretty much useless as you used it to describe what would be needed to get paint to stick to poly plastics. Since models aren't Poly, he likely won't encounter, nor need to encounter, these chemicals.

 

So, my (and others) reference to using hard styrene spoons for COLOR TEST stands, as well as using the styrene sprue for MATEIALS COMPATIBILITY.

Re-read my edited post.

And you don't know much about epoxies, judging from the above post.

And models ARE indeed POLYSTYRENE.

You really might get your stuff together if you want to go head to head with me.

Edited by Ace-Garageguy

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Re-reading your post, AGAIN, the info you give was for his initial spoon (poly). 

Your later argument about material being important for compatibility is also negated by the original posters reply of using HARDER spoons for COLOR test, NOT compatibility. I get what you are saying, but it becomes negated by his switch of spoon material and his PURPOSE. And if you wish to continue the 'argument', we can take it to PM as his post doesn't need be messed up by what will ultimately become a wiz match.

Edited by MarvinGardens

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1 minute ago, MarvinGardens said:

Re-reading your post, AGAIN, the info you give was for his initial spoon (poly). 

Your later argument about material being important for compatibility is also negated by the original posters reply of using HARDER spoons for COLOR test, NOT compatibility. 

No.

What is this "poly" you refer to"

All commonly used plastics are polymers...polystyrene, polyester, polypropylene, polyvinyl chloride, polyethylene...

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Furthermore...lacquers commonly used to finish models commonly contain solvents like MEK, acetone, toluene, etc., to various degrees...including those marketed specifically for models.

Many automotive products that were used successfully for YEARS on model work now cause problems with surface incompatibility as the quality of model POLYstyrene declines.

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10 minutes ago, MarvinGardens said:

Re-reading your post, AGAIN, the info you give was for his initial spoon (poly). 

Your later argument about material being important for compatibility is also negated by the original posters reply of using HARDER spoons for COLOR test, NOT compatibility. I get what you are saying, but it becomes negated by his switch of spoon material and his PURPOSE. And if you wish to continue the 'argument', we can take it to PM as his post doesn't need be messed up by what will ultimately become a wiz match.

You're the one who started wizzing.

I know more than you. Period.

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So you think, Bill. Sad life really, having to look down your nose at other modelers and give credibility to your life while doing so.  :-(

And while you are correct on some paints/adhesives containing those ingredients, it is the STRENGTH and amount of said chemicals that has the effect on styrene. You are NOT the only one with intelligence, get used to that.

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14 minutes ago, MarvinGardens said:

So you think, Bill. Sad life really, having to look down your nose at other modelers and give credibility to your life while doing so.  :-(

And while you are correct on some paints/adhesives containing those ingredients, it is the STRENGTH and amount of said chemicals that has the effect on styrene. You are NOT the only one with intelligence, get used to that.

Nice. Does making derogatory personal remarks make you feel better?

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Regardless, the harder plastic spoons I just bought are working just fine.

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8 minutes ago, crowe-t said:

Regardless, the harder plastic spoons I just bought are working just fine.

Glad to hear it. I'd like to apologize for these two roosters, more interested in crowing than a quiet barnyard.

Geez guys, take it to PM if you wanna squawk. 

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19 minutes ago, crowe-t said:

Regardless, the harder plastic spoons I just bought are working just fine.

Good. Which takes us back to what I said earlier...

"  "Flexible" plastic is not styrene. If you MUST test on spoons, get the "harder" ones. "

 

 

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What both Bill AND I were getting at is that certain paints and certain materials don't play well together. Since the original poster went and got the harder spoons for the color test, that is what mattered. 

I may offer up a word of advice here: What brand of paint are you testing? Reason I ask is that even on one of the harder spoons, I have had Dupli-Color leach through the primer and etch the spoon. It may have been my doing (I may have sprayed it either a bit too wet or without enough primer). Before you try the paint on the model, use a piece of the sprue the parts are attached to as a paint compatibility test. That way, you will know 100% whether your paint choice will work on your model. Having a model you spent so much time on destroyed at the paint stage sucks!

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Yep, after viewing some of the above post, like I said before that I don't use spoons at all except in the kitchen and at the dining room table.

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