[fatal-exception]

You would only need 55 amps if you are doing a part with 4.5 square feet of surface area. Use the formula 12amps/square foot per hour. If there were bubbles coming off the anode plates, then you are doing the right thing. Did you anodize your test part for an hour? Did the part slightly change color?

Is your part just not taking color? Maybe it's anodized, but your dye is no good? You can test if the part is anodized by using a multi-meter. The part will no longer be conductive.

Your acid water ratio should be 50/50. Battery acid you buy from the store is already diluted 50/50 so don't water it down anymore. Sulfuric acid for filling batteries is pure, so it will have to be mixed.

Other than that, make sure your acid bath temp isn't too low. I think it should be somewhere around the 65-69 mark.

Paul

[MBG]

What are your parts looking like?

This is what mine look like at with a dust finish.

[fatal-exception]

OK, well I have to ask, how do you get a dust finish? That part looks rad.

Here's some stuff I've done recently.

[MBG]

OK, well I have to ask, how do you get a dust finish? That part looks rad.

Here's some stuff I've done recently.

Your anodize looks good. Are you using what they call the LCD methods? I have my mixed thoughts on that process.


Also, I do it by bead blasting prior. It is like painting a car with over lapping strokes. It takes a little practice. Main goal is to get an even finish.

[fatal-exception]

Cool. I used to have access to a sandblast cabinet, but not anymore. Now I have access to a 200hp sandblaster mounted on a semi. Not too useful for my projects...

I dont know if 12A/ft2/hr would qualify as low density, maybe. That's what I use, and it seems to be pretty much fool proof. Can you do type 3 anodizing?

[MBG]

Cool. I used to have access to a sandblast cabinet, but not anymore. Now I have access to a 200hp sandblaster mounted on a semi. Not too useful for my projects...

I dont know if 12A/ft2/hr would qualify as low density, maybe. That's what I use, and it seems to be pretty much fool proof. Can you do type 3 anodizing?

12 amps for 2 hours? WOW.. you are making one thick and brittle coating. Your coating is over 1.5 mils thick at that CD and length of time. I never recommended anything over 1 mil for TYPE II anodize. TYPE III is fine all the way up to 3 mil (on certain materials)


Also, what temperature are you running at 12 amp for 2 hours? How many volts you getting?

[MarcoBernardini]

Americans are very lucky!
In the States it is possible to find cheap powder guns, like those of Harbor Freight... but all of them can work just with 110V :-(
Here in Europe there are just "professional" (read "expensive") solutions.
I think the DIY anodizing could be a good solution, so I'm trying to learn everything about it before to start.
A good solution to store the chemical products reducing the surface in contact with air (to minimize oxidation) is that used many years ago in the dark rooms: place glass beads into the bottle until the product is at the top level, so there isn't a lot of air between the cap and the liquid.

[MBG]

Americans are very lucky!
In the States it is possible to find cheap powder guns, like those of Harbor Freight... but all of them can work just with 110V :-(
Here in Europe there are just "professional" (read "expensive") solutions.
I think the DIY anodizing could be a good solution, so I'm trying to learn everything about it before to start.
A good solution to store the chemical products reducing the surface in contact with air (to minimize oxidation) is that used many years ago in the dark rooms: place glass beads into the bottle until the product is at the top level, so there isn't a lot of air between the cap and the liquid.

I actually am working on selling anodize kits. PM me if you are interested.

Also, when storing chemicals I just a bucket with a good seal on it. The product is fine for many years. What contaminates the chemicals is more of a cross contaminate (mixing the chemicals from process to process by run off and not completely rinsing the parts.)

I hope this helps.

[fatal-exception]

12 amps for 2 hours?

12 amps per square foot per hour is what I meant.