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Anodizing Advice and/or Services

Zanodize

Iron
Registered Member
#1
Hello, I stumbled upon this site a while ago looking to see if anyone needed parts anodized and today I see you guys put together a Metal Finishing Forum. Even if you don't need my anodizing services I can offer my professional advice. I specialize in anodizing small parts without crazy lot fees or prices. I have a few local machine shops I do business for so I'm no stranger to what a machinist wants when it comes to anodizing aluminum. Like tight thickness tolerances or just a decorative finish. I'll check in time to time to see if anyone needs advice on anodizing or needs anodizing done.


-Ryan
 

PurpLev

Active User
Active Member
#3
sounds good.

I'm now trying to see if I can setup a small scale anodizing environment as I have some small parts to anodize (some now, and if it works out, more later) and paying ~$100 for it just isn't worth it long term seeing that for a bit more I can setup my own thing which in a few more jobs will pay itself off.

I wouldn't mind hearing what you charge per project/size/etc to compare.
 

eac67gt

Moderator
Staff member
H-M Supporter-Premium
#4
Hi Zanodize.
I have been doing some hobbying anodizing and there are a bunch of my posts here to try and help people. I am a hobbyist and in no way a pro so your help is greatly appreciated. I am doing my best to try and answer the questions. In my process I am using sodium bisulfate. It has been giving me great results. Pros-Cons?
See the article http://www.hobby-machinist.com/content.php/345-Re-My-latest-anodizing I wrote or the thread http://www.hobby-machinist.com/showthread.php/12374-My-latest-anodizing I started and see what you think or if you have input of any sort. Once again I am a hobbyist and a pros input would be a good thing.

Have a great day!

Ed
 

Zanodize

Iron
Registered Member
#5
Hi Zanodize.
I have been doing some hobbying anodizing and there are a bunch of my posts here to try and help people. I am a hobbyist and in no way a pro so your help is greatly appreciated. I am doing my best to try and answer the questions. In my process I am using sodium bisulfate. It has been giving me great results. Pros-Cons?
See the article http://www.hobby-machinist.com/content.php/345-Re-My-latest-anodizing I wrote or the thread http://www.hobby-machinist.com/showthread.php/12374-My-latest-anodizing I started and see what you think or if you have input of any sort. Once again I am a hobbyist and a pros input would be a good thing.

Have a great day!

Ed

I did read your write up. I was surprised with the results you got using sodium bisulfate for an electrolyte. All Type II which is the common anodizing finish is done with sulfuric acid. I understand not wanting to deal with such a harsh acid but its easy to obtain from a Napa store and in small set-ups can easily be disposed of. Another small issue with your set-up is using boiling water to seal the part. This actually does hydrate the pores and closes them but with a dyed finish can cause very early fading. Sealing with Nickel-Acetate is highly recommended to completely seal in the dye and pores. For the most part you are anodizing and if it works go with it.


-Ryan
 

eac67gt

Moderator
Staff member
H-M Supporter-Premium
#6
My concerns with sulfuric acid are that, for the home hobbyist, it is more dangerous. It ranked higher as a toxic waste, labeled as a know carcinogen and just more dangerous to handle.
Nickel-acetate is another that is on the list of know carcinogens also.
I tried to somewhat stay away from more hazardous things but it is impossible in any anodizing. Limiting what you are using is more desirable.
If it was for a more critical application, military or industrial there is no doubt other ways would be more acceptable and at that point I probably would take the parts to an anodizer/plater.
One thing I have noticed, in general, when going to places like finishing.com or caswells and many others is there are a lot of conflicting answers to many of the anodizing practices.
I am a hobbyist and want the safest method I can use, for the most part because its hard to get away from some, that will give me acceptable finish and performance on the simple parts we do.
One thing I don't want to do is scare away any possible hobbyist from trying anodizing. Its fun its simple and it needs to be no more for playing/hobbying.
 

eac67gt

Moderator
Staff member
H-M Supporter-Premium
#7
Up date here and this is probably the best post to make this update.
I ran into one problem after another using the sodium bisulfate for anodizing. Even though I was getting great results, at time, there was issues with consistant finish. Using the sodium bisulfate method the normal anodizing calculations are not suitable so your kind of flying by the seat of your pants. The solution loses its ph level real fast leaving you with no fix other than dumping more money down the drain.
If anode was left in bath crystals would form on it in a short period of time. There has been many issues and people tried to tell me not to go this root.
Also in my process I used Rit cloths dye to dye the parts. This ended up creating some great dye jobs but if exposed to UV, like the sun, the color fades rapidly.
If you keep the part out of the sun, no problem.
I questioned the group at finishing.com about only sealing by boiling and they saw no problem there in most cases.
If a "tougher" finish is desired it should be boiled/sealed with nickel acetate solution.
I am in no way a pro at this but I am learning by going down the bumpy road.

Now to make my process more consistent I have finally switched over to using the things recommended by the pros. I guess they call them pros for a reason.
I now use sulfuric acid instead of sodium bisulfate, using pro dyes and sealing with nickel acetate.
Also instead of using my battery charger for power source I purchased a lab power supply that has constant current or constant voltage modes.
This works great. Using the proper calculations and then current settings have given me some of the best finishes I have achieved so far.
I also added a bubbling system to the tank to agitate the solution while anodizing.
One thing that has also corrected for me is I was having issues with keeping the tank temperature down depending how large the parts were.
This was corrected by proper current per part and being able to maintain that current.

I have learned a lot in my travels through anodizing but if you only want to anodize a couple parts and keep the hazards low I would still use the sodium bisulfate over sulfuric acid and also seal with just boiling water.
In most cases for hobbying anodizing with this safer method will suit.

Have a great day!

Ed