TSO Anodizing is very inconsistent, why?

[Crazyraceguy]

Let me add on to where Coen just ended, whether it's anodization or paint, accurately matching different batches of colored products is nigh on to impossible. Simply read the label on SW paint where hey exhort you to

This is why Pros use a technique called "boxing". Simply put, this is the mixing of multiple smaller containers into a larger one, thus blending away any variation. Then it can be returned to the smaller containers, for use as needed.

We often do this with stain too.

 

[Packard]

Specifically in the medical field where different color screws refer to different lengths. That way during surgery, instead of asking for a particular length the physician simply asks for a particular color. Easier and fewer mistakes are made.

Interesting.

In the early 1970s I was an independent manufacturers’ representative. One of my principals was a machine shop. At that time, I subscribed to a U.S. government publication called “Commerce Business Daily” [CBD] and it arrived my US Mail 5 days a week. It listed various government contracts being offered. One seemed to suit the capabilities of the machine shop I represented, so I requested a bidding package.

My principal bid the job and we were the low bidder. It called for machining 10 supplied castings, including milling and line boring. It seemed simple enough. And the contractor sent out a survey company to confirm that we were capable of doing the work. It was bid at $200.00 each for 10 pieces. What my principal did not notice was that he was responsible for any castings he damaged, which were made from titanium.

Luckily none were damaged. Each one was valued at $700.00. I referred to the material as “unobtainium”, which was my word-coinage at that time. The job went well, a the titanium caused no issues in the machine shop. However, when my principal learned the risk he had taken, it soured him on future government work.

CBD no longer exists. It has been replaced by an on-line version, which was always available for free. I am not sure what the Trump admin has done in that regard.

 

[luvmytoolz]

Let me add on to where Coen just ended, whether it's anodization or paint, accurately matching different batches of colored products is nigh on to impossible. Simply read the label on SW paint where hey exhort you to

Titanium can be anodized.

So long as it's not red! ;-)

 

[MMCO]

Interestingly enough, here's a photo directly from the TSO website.

My primary issue is with the two Parallel guides scales not matching or even being close. As mentioned in my initial post, it isn't as obvious in the picture due to lighting.

 

[Packard]

My primary issue is with the two Parallel guides scales not matching or even being close. As mentioned in my initial post, it isn't as obvious in the picture due to lighting.

I thought you were comparing the two different scales for color. If you are comparing the scales to the squaring plates, it is possible that the alloys are different, and the process for forming is different, and those differences will yield different colors.

The scales are extrusions.

The rail squares have machine marks over much of the surface. It is not clear to me if it was machined from billet, or started life as an extrusion. It would require an extremely large extrusion line to make that profile, and it would still need to be machined on a CNC machine. My guess is that it is made from billet, and quite possibly from a different alloy for improved machine ability and hardness.

Aluminum alloy 6061 is “plain vanilla” aluminum, and enjoys high availability and relatively low cost. It machines well, but is not particularly hard or tough. TSO might have selected a different alloy to improve the performance of the part or to facilitate manufacture.

Below is a link that lists several alloys of aluminum along with their properties. TSO almost certainly selects the alloy according to the physical properties required for the part and its ability to be machined and/or formed. Color matching is probably further down the list for consideration.

I agree that there is a huge color difference between the squaring arm and the scales. I have that same system, and the color matching o lack thereof, does not seem to affect functionality.

Do note that the colors will fade when exposed to UV rays. Of note is that blue and red dyes tend to fade the most; gold is nearly fade-proof, and black offers excellent UV resistance.

More on that here: https://www.anoplate.com/news-and-events/why-does-anodize-fade/

Excerpt here:

Anodized aluminum is for the most part a robust, quality finish that is readily obtained through any number of chemical processing houses, however, a persistent issue that arises is fading of colored anodize. The fact is that there are a number of causes for this, not always related to the processing houses cutting corners, so we thought we‘d review some of them.

[…] To begin with, anodic coatings are porous by nature and freshly anodized surfaces act as great receptors for dyestuffs, typically organic compounds available in a myriad of colors. The organic dyes used to impart color to freshly formed anodic coatings are the same as those used to dye textiles.[…]