Better color chart for Caswell dyes?

[luminous]

Welll... it looks like Caswell is having a sale on dyes, so I guess it's time to whip out the credit card and start getting some supplies....

I'll probably buy black HBL and maybe 4-5 other colors to start with, but I'm having trouble deciding between shades on some of them.

The color chart that Caswell has on their website for the dyes sucks, and I can't hardly tell any difference between some of the colors.

Does anyone have a better color chart, or photos of samples of any of the colors? Particularly the different greens and blues and the dark colors like the 2 browns and olive that all look black on my monitor...

Thanks!

[mcaswell]

Most people seem to see the colors on our web page. Of course, this will vary tremendously depending on each customers monitor. Maybe you should try looking on some one elses? Older monitors don't fair too well with these slight variations in colors.
AND of course, colors will vary depending on the operator, and the skill of the anodizer.

This stuff isn't like paint!

[luminous]

Sigh... Well, yeah, I can SEE the colors OK, I just can't distinguish between the darker ones very well. I've tried on 3 different monitors, 1 flat panel monitor and 2 different CRT monitors and although the colors vary a little, it's still nearly imposible to tell the darkest colors apart on any of my monitors, and I really doubt that the 2 browns, electric blue, and olive drab are all as close to black as the chart implies.

Can you honestly tell me that folks can distinguish between brown GL and brown BL on your chart?
It seems pretty unlikely, since those 2 color swatches are IDENTICAL, both with hex color values of #1A0D02. Are the 2 dyes also identical?

I see others have complained about the chart before on this board, so it must not just be me....

Steve

[scocklin]

Getting the true color from a dye is highly subjective and depends on the types of controls you are using during the anodizing process. I have purchased many of the Caswell dyes and tried most of them with somewhat good results. I’ve found that good results depend on a number of factors;

1. Proper mix using distilled water
2. Tight PH control especially with red dyes where I mantain a PH range between 5 & 6.
3. Acid bath temperature (I try to keep my bath temperature between
69 and 72 degrees F)
4. Dissolution, The more dissolution you have the larger the pours in your anodized coating. Larger pours readily accept dyes especially with reds. I tend to watch the voltage decrease somewhat on my CCR before stopping the process. The colors turn out richer with deep color saturation.
5. Dyeing time, when I’m dying a piece I check it constantly. If I’m matching a color I’ll pull the piece and rinse it before comparing.

You will never see true colors using a color chart it doesn’t matter if you’re sizing up dyes or paint. Color charts are Ball Park accurate. The best way to determine color grading is to buy the dyes and test them.

[luminous]

Originally Posted by scocklin

I’ve found that good results depend on a number of factors;
(snip)
2. Tight PH control especially with red dyes where I mantain a PH range between 5 & 6. (snip)

Thanks scocklin for the tips.

What do you use to adjust the dye pH?
I don't see anything about it in the Caswell anodizing manual (lcd_ano,pdf) and my dyes arent here yet....

If I knew what was used to adjust the pH I might be able to hunt some up this week.

Thanks much!

[scocklin]

Household ammonia to bring the PH up and battery acid mixed with distilled water at a 3 to 1 ratio to bring it down. I use an eye dropper and only use one or two drops at a time. I find that adding the acid or base to dye at a temperature between 135 - 140 degrees F works best. I use a small PH meter I purchased through Caswell to measure the PH.

I almost never have to raise the PH but usually have to lower it. But never add more than one or two drops at a time. Add the acid stir and wait before taking a reading. If you add too much you will have to correct using the ammonia again one or two drops at a time

[Sid03]

really? Im the opposite...ive never had to raise my Ph, only have had to lower it.

I use lab grade acetic acid to lower my Ph, which is what the manufacturer recommends(I actually have the exact same stuff they use). I have never tried ammonia.

[luminous]

scocklin,
Thanks for the tips on adjusting dye pH! But isn't it backwards? Wouldn't you use the ammonia to RAISE the pH and acid to lower it?

Sid03,
Where do you buy the lab grade acetic?
I wonder if food grade acetic acid would work as well. I can probably get that locally...

Thanks guys!

[scocklin]

I just made the edit, your both absolutely right, I DID get it backwards and yes Sid03 I usually have to lower it also. Sorry about that. I've been using diluted battery acid for some time now and never had any problems, I think I read through past forms and got the procedure from one of the past post. But I'm always open to new ideas where do you get your lab grade acetic acid Sid03.

[Sid03]

Reagents, Inc