Crazy Experiment Time - selective multicolour anodizing

TorontoBuilder

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Okay, I want to try something very far out, selective anodizing a rating plates and gear selection tables and the like.

I have access to anodizing company via a business that regularly has parts anodized. I was thinking that I can get the parts anodized and take delivery of them within hours of the end of that process and then dye the plates myself with an electrolytic process combined with organic dyes.

The tricky part of attaining quality anodized layer of suitable thickness is left to the professionals, and I try the hard selective dying process the professionals may want too much to perform.

I'd use a minimum of three dye colours, and use multiple masking layers of laser cut green polyester plating film. Orange base layer overlaid with purple and black layers to bring out orange text with two different colour surrounds. Dying of aluminum anodization does not always follow typical colour rules... but normally of you overlay purple on orange you will get brown. If this is the case I'd just have a more complicated masking task that required careful registration of the layer masks.

and multiple masking and repeated dying steps.

The goal, to recreate something like this:

20220907_082508_resized_1 (1).jpg

But on aluminum where all text is orange, the red changed to deep purple, and the black being black of course. I don't think I shall fail.

If I fail my fall back would be multiple coats of paint spray applied with similar masking techniques.

Yep, I'm aiming for a true showpiece lathe
 
Interesting experiment.

It's been many years since I've used my limited knowledge of aluminum anodizing, so excuse me if these are silly questions.

IIUYC, you'll have the parts anodized Type 2, but undyed and unsealed?

If the sealing step is omitted, I wonder if time/atmospheric exposure (between anodize and dying) will cause a significant problem getting the dye job you want?

What post-dye sealing process do you have in mind?

Good luck. I'll be following this thread with interest.
 
I think you should also do the anodize step so you can dye right away. Not that big a deal. several threads here on how to do it. I have a thread over on weapons guild on how to. https://weaponsguild.com/forum/index.php?topic=64679.0 Start with Caswill for supplies.

I'd be tempted to mask off before anodize, then anodize, dye, and seal. remove mask1 then mask over anodized and dyed area. Anodize again. Already anodized is not going to want to react anyway so a tiny leak will not kill you. Then when dyeing, the previously dyed area should not want to take up more dye.
 
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I think you should also do the anodize step so you can dye right away. Not that big a deal. several threads here on how to do it. I have a thread over on weapons guild on how to. https://weaponsguild.com/forum/index.php?topic=64679.0 Start with Caswill for supplies.

I'd be tempted to mask off before anodize, then anodize, dye, and seal. remove mask1 then mask over anodized and dyed area. Anodize again. Already anodized is not going to want to react anyway so a tiny leak will not kill you. Then when dyeing, the previously dyed area should not want to take up more dye.
Interesting experiment.

It's been many years since I've used my limited knowledge of aluminum anodizing, so excuse me if these are silly questions.

IIUYC, you'll have the parts anodized Type 2, but undyed and unsealed?

If the sealing step is omitted, I wonder if time/atmospheric exposure (between anodize and dying) will cause a significant problem getting the dye job you want?

What post-dye sealing process do you have in mind?

Good luck. I'll be following this thread with interest.
Karl, I have a lot on my plate at the moment and very very limited space. I think adding this type of process to to inside of either my or my brother's house would be the proverbial straw....

I want to do it all, believe me.

Ex, correct I'll have them done using type 2, which is what the shop my acquaintance gets for their parts. In hindsight I only need organic dyes to meet my needs so should be easier. I'll be able to pick up the parts almost immediately after they're anodized so I hope not to have any problems. I can have my dyes all set and waiting.

I anticipate that the greatest issue will be masking related, particularly getting smooth edges on the tiny cut out letters, and removing the cut out pieces from the masked part. I've had similar issues when using same technique in spray painting. I will mask, then low power laser cut the masking film, then pick out the areas for the color I wish to dye. Rinse and repeat for each of the three colours I anticipate using.

I'll likely just seal with the same urethane clear coat I'll use as the final finish coat on my lathe.

I'm lining up a back up plans as well...

Option 1:

Dye the parts solid colours in their respective areas, and then use laser printer to mark the graphics. This of course means I'll only get white text on black and purple, unless the laser I use is strong enough to create a deep etch into which I can rub orange urethane paint.

Option 2: Have the plates lightly blasted to create dull matte finish. Plain anodize and seal the plates. The create waterslide decal of the graphic, affix decal to the plate using water based urethane as follows:

Coat the plate with thin even coating of matte urethane... allow to tack up. Apply the wet decal by sliding it into position and then wipe off excess water with a damp sponge brush and tamp the decal into place. Then I'll cover the decal with a clear plastic film and run the plate thru a cold laminating press. This should bond the decal sufficiently well so that it does not delaminate in the future.

Then I could cover with one or more coats of matte urethane to seal and protect the decal and to seal the edge of the decal (which must be smaller than the plate) so the edges dont lift. I have some similar decals I put on finished wood boxes that have lasted years without damage, but they didn't get rubbed and cleaned as often as the plates will.
 
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it will be interesting to see your results. I think you will have considerable challenges getting the resolution (the thin lines) without bleed through or affecting any subsequent dying steps. I've read about 2 step anodizing, using superglue as an infill mask, and tried it without success. I ended up anodising the infill and machining off the dyed layer around it to create the contrast.

A pretty common approach to achieving what you're after is anodising followed by etching (laser I think) or engraving. Only 2 "colours" but very straightforward.
 
it will be interesting to see your results. I think you will have considerable challenges getting the resolution (the thin lines) without bleed through or affecting any subsequent dying steps. I've read about 2 step anodizing, using superglue as an infill mask, and tried it without success. I ended up anodising the infill and machining off the dyed layer around it to create the contrast.

A pretty common approach to achieving what you're after is anodising followed by etching (laser I think) or engraving. Only 2 "colours" but very straightforward.
Masking film has been used extensively and will only cause bleeding if the edge is ragged and cant be pressed down firmly.

Mask material adhesive does not impact subsequent dying as far as I know, it's why I selected it over say a screen printed mask that would yield the resolutions I desire. I may have to try screen printed masking too if the wash out does not affect subsequent dying.

I really want the text in orange, so the etch is likely out unless you have a fiber laser I can borrow?

There are companies that do very precise anodizing and subsequent laser etching using a special process where they can vary the depth of the etch by microns and change the colour of the underlying substrate based on how much dye is removed. Of course I don't have such a laser. A friend has an etching laser but I'm not sure it is the proper type.

I suppose that could also be used in a multi-dye process where a black was dyed over a based orange... and then just the top black was burnt away to reveal the orange. If I were rich and had access to the type of laser required maybe I'd try it.

fiber laser.PNG

I had even contemplated screen printing the plates using three screen colours but again that is less durable option.
 
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