I wanted to start a thread for any other nerdy type like myself to gather some info on home anodizing setups. I know we have some folks here with mills at home and may dabble in anodizing already (@Bigdaddyhawk ?). I am just getting into the world of very small-batch CNC work and would like to be able to finish off the work with a nice outside finish if possible. My parts will be small and typically 6061 or 7075 aluminum. Black is the first and main color I’d like to be able to tackle.
I’ve gone down the YouTube wormhole a bit and have looked up some kits from companies like Caswell.
I wanted to see what others have used, as well as any tips/tricks/advice surrounding the process. I know it’s not for the faint of heart, using battery acid and such, but obviously with care and caution it can be done safely.
I have messed around with this a little bit. But really haven’t had time to get into it.
I picked up anodizing dye from
amazon
Titanium wire (amazon) for anode (or cathode, i forget which off the top of my head)
Battery acid from AutoZone (had to ask for it and they had no clue what I was talking about, but one of the old timers knew they had it out back.)
Bench top power supply (Amazon)
I tried once before I had the titanium wire when I was being impatient band it didn’t work. I did end up electroplating the clips that I was using with copper.
So a good sign that the setup does work, I just didn’t take the time to do it right and have a handfull of other projects that are higher priority right now
If you wanna get rid of the stuff you bought, I’d take it off your hands. Titanium wire definitely sounds like a must, since aluminum wire will just anodize itself and have to get tossed after using it once.
Vibrator
It was emphasized to me that to get professional results one must use a vibrator. One like this for under 100 bucks. It’s for small parts …its a 5lb tumbler with an opening about hand size.
You will also need to buy media for different finishes. Use smaller media size that will get into tight places. The media also needs a liquid added to it that looks like this
Many different types of liquid was tried but nothing else gave the needed results so I was told it’s a must have.
Heaters
I was convinced I could pull this off without the expensive heaters but in the end decided to grab two of them to make things go a lot faster. The good heaters work extremely fast and will catch your shop on fire if left on any surface except in the liquid. Also can’t touch the hdpe buckets.
Storage containers
Once you have all the different colors mixed up in Rubbermaid containers it’s best to get ones that have really good lids because they will also sit in that same container until you use it again. Storage of the kit takes up a lot of shop space but they do stack well on top of each other.
Did you decide to anodize these yourself? I just ordered some basic supplies for DIY anodizing so any tips you might have would be great. I know not to drink the battery acid…
Positive clip goes on the part, negative goes on negative anode
Wait 30-60 min
Dunk in sulfuric acid neutralizer
Distilled water dip
Dye bath 110-140f for 10 min
Boiling water for 20 min
I used 18 ga aluminum craft wire. It was a little bit small and weak, but did the trick. I’d go with wire a little bit thicker next time.
The issue that I was having, was not having great contact with the part and the aluminum wire. I ended up shoving a bunch of the wire inside the pulley so it was forced to make good contact. Before that I was not getting much to happen.
Tried titanium wire but had some issues. Originally got 2mm wire but it was very stiff and hard to work with. Then I tried to order 1 mm, but I think 22ga showed up. The 22ga was too thin. 1mm probably would have been about right.
As long as you get the surface uniform with sandpaper or scotchbrite you should be ok.
Yes I just used whatever came up as “professional anodizing dye” on Amazon. Apparently rit works pretty well, but I guess doesn’t have too much UV resistance and can fade.
Something I didn’t really think of is that you save the dye, at least I do in a milk jug. So $20 vs $10 isn’t so bad when you can re-useit a ton.
Again my biggest issue was just getting the wire to make a solid connection. Think I just figured out a little trick if your part has 2 holes.
Run the wire through both and then twist it together so the wire tightens up and puts pressure on the holes like in this pic
Good luck and remedy if you mess up or don’t like how it came out, then you can just soak it in the lye again to remove the coating
titanium wire (i’d prob try 1mm) 2 was too stiff and .6 was too flimsy)
aluminum wire (I had some success with this, but a little bit thicker would be better.
Polypropylene containers (I got 3 packs of these so I’d have 6 tall containers (24 oz). The containers do a good job, but I imagine there are more spillproof ones. I have denatured alcohol in one of them and it likes to spill with the lid on a little bit.)
