Model Railroading > Fixative Shootout (Part 4)

This is a continuation of the original Shootouts,
 
Part 1:
https://www.trainorders.com/discussion/read.php?3,5069479,5077550#msg-5077550
 
Part 2:
https://www.trainorders.com/discussion/read.php?3,5086356,5087648#msg-5087648
 
Part 3:
https://www.trainorders.com/discussion/read.php?3,5116682,5117197#msg-5117197
 
In Part 3, several “Fixers” for Pigments were tested.  The manufacturers of the Armor/Aircraft “Fixers” also offer their own line of weathering powders, which they call Pigments.  Would we obtain better results using their Pigments with their Fixer?  How would Dead Flat perform when the competition has the Home Field advantage?  There’s one way to find out!  Again, the tube is sprayed flat black, but instead of Pan Pastels, the Pigments from the Armor/Aircraft manufacturers was applied.  The Pigments for a specific mfg was applied to a ¼ section of the tube, and the companion Fixer was applied on their Pigment sample.  The Fixer was applied first, then Dead Flat next to it for comparison.  All were applied with an airbrush.
 
The Test “Car”
As in the previous shootout, a section of 1” PVC pipe served as the “car” to apply the samples.  The weathering Pigments were applied with a Q-tip.
 

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The products are placed behind their sample, in the order applied.  From left to right:
 
Vallejo Airbrush Thinner  
      73.108 “Brown Iron Oxide” Pigment on upper half.
      73.118 “New Rust” Pigment on lower half.
There was some “pooling” of the color, with water marks creating slight halos.  Dead Flat did better, especially on the lower New Rust color.  The Vallejo Airbrush Thinner nearly “erased” the New Rust.
 
AK Interactive AKI-048 Pigment Fixer
     AKI-044 “Light Rust” Pigment on upper half.
     AKI-040 “Light Dust” Pigment on lower half.
AK Fixer had a darker color shift, compared to the Dead Flat.
 
MIG 3000 Pigment Fixer
     MIG-3006 “Light Rust” Pigment on upper half.
     MIG-3002 “Light Dust” Pigment on lower half.
The AK and MIG bottles were identical, same descriptions, with different logos on the labels.  I was expecting them to be the same product, with a different label.  However, the AK Interactive pigments had better adhesion, as well as differed in color.  The Rust color was pretty close, but the Dust was significantly different.
The MIG Fixer did have similar results to the AK Fixer.
 
502 Abteilung ABT-P249 Pigment Fixer
     ABT-P024 “Light Rust” Weathering Pigment on upper half.
     ABT-P026 “Concrete” Weathering Pigment on lower half.
Dark color shift.  Surprised it didn’t perform better, as its performance in Part 3 was noteworthy.
 
In all cases, Dead Flat still beat the competition, but the margin was not nearly wide as in Part 2.  Though I have a bunch of Pan Pastels, I was willing to put them aside if one of the Fixer + Pigment combinations had less color shift.  But good ol’ Dead Flat out-performed the Fixers, on their own Pigments.
 
As a side-bar, these Pigments are pretty much just that, pigments.  They are a powder, and lack the binder/carrier found in Pan Pastels.  Consequently they did not adhere to surfaces as well.  Some demo videos show them being sprinkled onto relatively horizontal surfaces (such as scenery) which would work well.  For example, to simulate the look of a grenade blast on concrete, the pigments can be put in a pile and then blown (with a straw) outward in a radial pattern.  The powder flows freely and is a good medium for this effect.  This would be more difficult with Pan Pastels as it would tend to want to hold-together. 
 
However, for vertical surfaces, the Pan Pastels performed better.  The Pigments required a flat finish on the surface to be weathered, and even then would not adhere well.  Scrubbing the Pigments into the surface with a brush or Q-Tip did little to increase the amount that stuck to the surface.  If a fresh coat of paint was mostly dry, but still tacky, that would help adherence.  However, for a large surface area, getting consistent results would be a challenge as the paint continued to dry and its state of tackiness is a moving target.  (Blasting it with Pigment quickly is an option to obtain consistent tackiness over the entire surface area, but the I dislike being pressured to obtain a weathering effect; especially if it risks spoiling the project and needing to start over again.)  About the only way to increase the intensity of the Pigments is to build-up multiple layers with Fixer in-between.  This is deemed an acceptable scenario since most accomplished armor modelers will use 25 to 50 layers of different Paint, Washes, Filters, Pigments, etc. to obtain the desired result.  Though I agree with the concept of layering weathering effects, I don’t have the time to make a career out of a single car.  A process that produces the same effect with less work, gets my vote.
 
CONCLUSION
 
I didn't want to discover a better Fixative was available, if I had only taken the time to look for it.  Having an engineering background, I like to have as much data as I can get prior to making a decision.  Sometimes the only way to get the data is to perform some R&D.  After testing nearly 30 different contenders for the title of Best Fixative, I’m pretty confident that Dead Flat will be my fixative of choice.  I was pleasantly surprised to see the minimal color shift.  (At times I had to do a double-take to see if the Dead Flat had been applied or not!)  It exceeded my expectations, especially based on the plain-Jane packaging.  The results were even more impressive when the products of well known paint manufacturers came close, but couldn’t equal the minimal color shift.  In spite of their professional-looking labels and bottles, the Big Guys could not deliver better results.  The product’s ability to protect the weathering effects with minimal color shift is my primary concern.  The Fashion Statement made by the packaging is not even on my radar.  There may be something else that I encounter in the future that will beat it, but for now, Dead Flat will be protecting the weathering effects of my future projects.
 
Admittedly, the black background was a worse-case scenario for weathering powders, as any alteration of the pigment appearance became readily apparent.  The choice of flat black, as well as the tube-shape of the “test car”, was driven by the main reason for this quest for a fixative, the weathering of a full string of 61 Oil Cans tank cars.   The goal is to replicate, as faithfully as possible, the weather-beaten look of that iconic consist that was once indigenous to Tehachapi.  The amount of work required will be non-trivial, and being confident that the fixative will have minimal color shift is paramount.
 



Edited 2 time(s). Last edit at 10/08/20 00:39 by tmotor.

A problem with weathering is paint spekles that stand out from overspray. Have seen several nice models ruined by that several on ebay that I would have bought and glad I took a close look. Would rather have them without instead.

This is an amazing effort on your part and I know I fully appreciate your work and willingness to share as many others I'm sure do also. I do have a request for another product, unless I missed it. How about Clear Wood Finish Satin? A couple of brass painters turned me onto the product and works well. I have not gotten the Dead Flat yet, but plan on getting some and then painting. However, with the holiday season, my other hobby takes over until January 1. 

Thank you again and keep sharing all of your findings. Great stuff!! 

Mike ONeill
Parker, CO

Thanks for your considerable research and qualified findings!  This is super valuable.

I do have some additional questions though:

1) After the fixatives have set, how well do the pigments adhere to the surface of your test subject under casual handling for each fixative?  Say.. after average (not overly gentle) thumb and forefinger pressure to the side of a boxcar to rerail it during a run session?  

2A) Does the fixative (Dead Flat or other brands) actually make a big difference in preserving the original appearance of the pigments after casual handling?  Is one brand of fixative better than the others in the above Scenario #1?  If so, which one(s)?
 
2B) Or do you lose a bit of the appearance even with the fixative, and if so, how much?  


Thanks again for any feedback.

Best Regards,
Harry



Edited 1 time(s). Last edit at 10/09/20 11:58 by tracktime.

The "fixers" that are used to seal the pigments to the model is plain old mineral spirits. Weathering an armor model is an entirely different beast compared to model railroading. Fewer vertical lines compared to horizontal lines for armor and far more vertical lines compared to horizontal for model railroading. The goal of weathering in armor is to create an extremely used battered and distressed vehicle were as weathering in Mr land is to a well used and exposed to the elements car or locomotive.
Cheers
Charlie

Posted from Android

mcdeo Wrote:
-------------------------------------------------------
> How about Clear Wood Finish Satin? A couple of
> brass painters turned me onto the product and
> works well. 

The pattern has been that if the fixative were water-based, it will have the least color shift.  Any acrylic, enamel, or lacquer-based fixative will have a darker color shift.  
Does the brand matter?  I might have some Satin Clear around to try.  It probably works well for protecting paint and decals, but for the specific purpose of weathering powders on a black tank car, I suspect it will have a dark color shift.

tracktime Wrote:
-------------------------------------------------------
> 1) After the fixatives have set, how well do the
> pigments adhere to the surface of your test
> subject under casual handling for each fixative?
>  Say.. after average (not overly gentle) thumb
> and forefinger pressure to the side of a boxcar to
> rerail it during a run session?  

That is the next set of tests I will run.  Durability during handling is important.  
Another factor is layering.  Can I layer one weathering effect one top of another, with the fixative in-between?  
I am a fan of using Future (floor wax) before and after applying decals.  How does this affect the fixative, under or over the Future?

> 2A) Does the fixative (Dead Flat or other brands)
> actually make a big difference in preserving the
> original appearance of the pigments after casual
> handling?  

I'm sure that it will be better than having no protection at all, especially considering the amount of weathering required for my Oil Cans project.  The trick is to find one that has minimal color shift, AND provides protection during normal handling.

> Is one brand of fixative better than
> the others in the above Scenario #1?  If so,
> which one(s)?

I will try the top 3 performers and see how they do in a trial weathering project.  

> 2B) Or do you lose a bit of the appearance even
> with the fixative, and if so, how much?  

Long-term use is another factor. 
I examined a new Santa Fe Warbonnet engine with my bare hands, and carefully placed it in the original packaging.  Came back a year later to take it out for a test run, and found my fingerprints etched into the paint.  :-0 
Note To Self: Wear gloves when handling engines with silver paint. 
Will skin oils also affect the fixative?  Assuming it is over-coated with Future, probably not.  One way to find out...
 

nikon1 Wrote:
-------------------------------------------------------
> The "fixers" that are used to seal the pigments to
> the model is plain old mineral spirits. 

The box containing the 502 Abteilung Fixer bottle was crushed in shipment, and the bottle ruptured.  There were 2 MIG books on weathering in the same box, and the books soaked-up most of it.  I was expecting the text and images in the books to run like they were being dissolved, but other than the pages getting a little wavy, there was no damage to the books.  The smell and "feel" of the Fixer was just like mineral oil.  It has a thinner consistency than straight mineral oil, and could very well be mineral spirits.