Ed --- We need a How-To on Anodizing. I wish to learn the process and I am quite sure many others here are as well. I know you said you are new to it but by the looks of your pieces you are well enough along to do this. It's your call but it would be greatly appreciated by all. ------ "Billy G"
I have a hard time getting thoughts in order for explanation but I will definitely work on it because I am up for the challenge.
I will work on it off line and then post it up with steps and pics.
Great idea and thanks for you confindence in me.
Have a great day!
You can definitely mess up the threads. The NaOh will attack of course the thiniest metal or at least that is of course where it is most evident.
I have done this myself. There is a learning curve. Unfortunelty I fly by the seat of my pants so I have gone through some messes.
One of the best controled way is to use a product called greased lightning. It may not be available to you in your country.?
Being it is a already mixed solution it works great to slowly removed the old anodizing on a part. It takes about 1 to 2 hours for a good job.
I also use pure lye. I get it at the hardware store as drain opener. This can be very dangerous to you and the parts.
I put 1 to 2 teaspoons in 2 quarts of water and depending on the part being stripped it takes 5 to 10 minutes at most.
Once again this can easily damage the part that is why I suggest the other method.
Now you could dilute the mixture more.
What I do is, wearing gloves of course, constantly agitate the part and scrub it with a tooth brush. This way you help it along and you can monitor the progression of the stripping.
Once again the lye burns. If level of mixture is to high the solution can reach in the 300 degree range. I was warned of this by someone else.
This made me curious so I put a table spoon in about a 1/2 cup of water in a plastic container and it steamed and the fumes were strong.
The bottom of the platic container melted quickly. I don't recommended doing this but I am a little nuts.
In all these things you always need to remember to protect the hands, protect the face, lots of ventilation and never lye near the acid your going to use for anodizing.
Bottom line safety, safety, safety!
I hope I helped.
If you have more questions I will try to answer all questions.
if you got small treaths the caustic will attack it an make the treaths ore holes bigger (i got some M3 treatsh in my parts)
i clean my parts also with the drain unblokker a few table spoons in hot water
and then i drop the parts in fizzes a lot and the parts come out some white somethimes black (depends on the alu used )
i started color anodizing years ago andthen there was no color die avalable in belgium
i dit it with cloting die and had some times goed sometimes bad results
a very good tip is only use demi water for everything
i do not want to hack your treath but here are some pics of parts i dit not the side plates
only the frames i made them myself from scratch and home anodizing
Very nice work & awesome colors. We used to have an anodizing department when I worked at Mansfield Aircraft years ago but it was just the ugly plain anodizing no colors. Anodizing shure has come a long way.
I always use distilled water for the processes. Our water here, even though public, still leaves mineral spots.
One tip I saw but haven't ried for the stipping part is to use plain rubber cement. The caustic soda will not eat it and it easy to remove.
There will be some leaking around the cement but it is better than elaving important parts unprotected.
A question for you is if you made the parts yourself are they the ones you are using the lye on.
For new parts all you have to do, I have found, is clean them extremely well. For a good job I always use a de-greaser like simple dish soap or I use Purple Power.
I like Purple Power because it will not harm the aluminum and does an excellant job removing grease. I have used it in the garage for years.
After a good wash and rinse I dip it in to an acid cleaner that actually etches the aluminum slightly. I giess you could say brighten.
The one I am using I got at the auto body supply shop. It is called Pro-power Acid Cleaner C-24. The sales guy said the truck drivers use it to clean the big aluminum tanks of tractor trailers.
Also he said the fireman use it to clean aluminum parts on some of the trucks. It is not a good thing to clean sensitive aluminum parts like wheels on your car though.
Anyway this particular product contains sulfuric acid, phosphorics acid and hydofluoric acid. It is highly concentrated and gets diluted 10 to 1.
I have a container premixed that I use to dip parts in over and over again then spray them down with distilled water.
I have found this process to prep the parts perfectly before the anodizing bath.
Once again I learned this through trial an error and lots of research.
Once again I need to stress safety! Safety! Safety!
Don't want to scare anyone off from doing anodizing. You just need to be careful and not rush.
I find all of it less danagerous than getting by the wheel of the car.
Once again I hope this helps and I am working on a process of how I anodize but it could take a few days being I am in the middle of relaying out the shop.
yes own build from plain round aircraft grade alu
and i used the lye on those
and like you i use distilled water ore i get clouds in the color
polish the parts (after that only use latex gloves when handeling the parts)
wash it wit dishwasher detergent / rince /
dip it in the lye /rince /scrub again /rince /and in to the acidbad/anodize/rince /
very hard to find those chemicals you mentioned over here
the only thing i still got problems with is the current settings and anodizxing time
as far as checmicals us americans get our hands on what ever is dangerous to us or the enviroment :think1:
being I have issues with number calculations after brain surgery I don't do the calculations
I fly by the seat of my pants and watch the part and I know that for the small parts I do it takes 2 hours.
I keep an eye on the color of the part because as you have seen the part gets a amber ting to it when the layer has built well enough.
There has never been an isse and several of the parts done this way I have tested by trying to remove to finish with a unitized wheel and it was very hard to even start to remove it.
It isn't like I have to meet a spec for production so whatever.
Well that depends what you are anodizing as far as what you are willing to have marks where the anode was attached.
In most of the parts I do which are typically round I bend 1/16" x 1/2" aluminum in a u shaped end and lightly force it into the end of the piece. The spring of the aluminum will hold it securely in your piece you are anodizing.
Now there are pieces such as focus knobs that are thread internally and the thread does not need to be anodized or at least it does not show and once again I use the same stock 1/16" x 1/2" and taper it so I can screw it into the threads.
In my one photo you will see my color samples. Under the color name tags I had 6-32 tapped holes and used 1/8" soft aluminum wire that I threaded and screwed it into them.
There always has to be a sacrifical spot that will not be anodized and this is where that anode attaches. The important thing is the anode has to be a good connection by screwing it in, spring tension, wrapping around it tightly or even as Caswell's sells a way to tack weld your anode on.
Doing this for a business, it will be difficult to stay "under the radar." You really don't want to attract attention from regulatory agencies. I remember looking into it and doing a few experiments years ago when I was already fabricating printed-circuit boards where I worked. It turned out to be simpler and cheaper to send our parts outside.
I want to make clear that I am not doing this for a business or anything else. I am disabled and my day to day condition varies which makes me extremely unreliable to do a business.
As far as my son he is tinkering and sells a couple things to his laser buddies for hobby.
He is a full time student home on co-op right now for his engineering degree he is studying for.
I just wanted to make it clear so no one gets the idead I am in business doing anodizing. I hobby just like I hobby with machines, cars, my chores and trying to take care of my family.
It would be so great to start a business or be back at my career of repairing industrial programmable controlers for Honeywell.
I am willing to discuss my experiences in anodizing or machining from hobbying but in no way am I an expert at any of them or have I ever said I was an expert.
it is fun to see that with the you got the same approche to it as i do
regarding the Amp's and time
what i also look at is the current drop due to the part anodizing layer is an insulator
i do al of it in my garage with the door open and a fan blowing the fumes out
also watch out if you got bare metals in the proximity the acid fumes make them rust very quicly
i like to buy some of those balls to blok the surface ofthe electrolit bad
This will be my last statement about "business" and is no way meant to upset or offend anyone.
I think we all, in our hobby, find times when someone comes to you and says how much to make me a thing-um-a-bob.
You now say no, ok I'll do it free or to keep the loop closed you say ok 20 bucks.
This if seen and desirable to others and you pursue it then you can grow a business.
Boy would I love to grow a business. I know my son has all the smarts for it in every aspect.
With my condition I can't support it.
Anyway I think we all or most have fiddled around with a little "business". It is the American way.
I apologize if I offended anyway by my previous post or miss lead anyone.
On the subject of anodizing. It is a hobby but I have, in many peoples opinion, gotten it down pretty well.
It was a definite adventure and I learned a lot.
I am most willing to share my findings and explain my process and one day soon, after finish helping relay out the shop, I will write up s simple how to on anodizng from my view point.
I use sodium bisulfate NaHSO[SUB]4[/SUB] with distilled water. It is what you would use to decrease the ph level in your swimming pool or spa. It is much more safe all around. I don't ge them nasty holes eaten in stuff, bad fumes (even though you will always get hydrogen gas off of anodizing) and it is much more easier to dispose of.
It can be tested in the anodizing tank just like the sulfuric acid by using the hydrometer used for batteries. The mix would be made so the bulb is in the red for specific gravity just like the sulfuric mix.
It is definitely a safer way to go but is still an acid. Caution still must be taken. But back to the original question or thought and that is I don't have as bad a fumes so as much ventilation is not needed.
I've seen the balls you are referring to and there is an addittive to decrease the bubbling that causes that acid splashing around. I have seen the larger bulbs coming up and causing little splashes but luckly I have nothing close enough that it appears, at this time, to be getting on. You can see a little white poweder on the black plastic I have down directly around the bucket but I don't see it anywhere else.
I keep a half a dozen 1 pound boxes of baking soda sitting close by so incase of spill I have something to throw on it.
There is a spot in my garage floor directly under my tractor where some battery acid slopped and it did start to eat the concrete. So anytime I accidently drip this particular solution on the concrete I take no chances and put some baking soda on it.
My wife parks her van in the other half of garage and is so worried about the whole anodizing process. I keep it spotless so you would see if any type of mist was carrying that far an it does not. The van is a darker color and it would show up as a white dust.
Anyone has any questions or thoughts on anodizing I will try and help.
Remember I am not an expert but a hobbyist.
I am still planning on doing a writeup with pics on my anodizing process once shop is totally back in running order. Please bare with me those that asked.
DIY Home Aluminum Anodizing by eac67gt I was always curious about anodizing and finally after some research dove in and after trial and error finally came up with some good results. Though I haven’t used much technical calculations in my anodizing there are calculations to get the process exact. I have learned by watching current, voltage, tank action and color change of the part being anodized when to call the part anodized and ready for dye. I will step through the process from beginning to end as I performed it. I am not a chemist or professional anodizing expert I am just a hobbyist.
For this write up I re-anodized a flashlight for my sister. Though it was in fine shape she wanted it green. Before- View attachment 48320 After – View attachment 48334 Anodizing is an electrochemical process that creates an oxide layer on the surface of the aluminum. This layer resembles a honeycomb that dye fills and then is sealed in boiling water.
First thing I must stress is SAFETY! All chemicals used can be dangerous. Acid is used in the anodizing process and a strong alkali isused in the prep process. THESE DO NOT MIX! Acids and alkalis are very unfriendly to each other. Keep them in two different areas when using them. When mixing acid and water you always add acid to water not water to acid. This is what they call the three AAAs. Always Add Acid! Pouring water on acid can give a very severe reaction. You need to protect yourself with gloves, eye protection, respirator and apron. Ventilation is important in this process due to fumes which can damage your respiratory system and the anodizing process gives off hydrogen gas which is explosive if it builds up. The process of using chemicals can be very dangerous but do not be afraid just be careful. Safety is always important but if you are careful and take your time the process is simple and safe. Most anodizing processes use sulfuric acid (battery acid) but the process I will explain uses sodium bisulfate which is a much less dangerous acid that is a byproduct of sulfuric acid and is actually what you use to decrease the PH level in your pool or spa.
Materials needed: (as I did it) ·Distilled water – I started with a case of 6 gallons ·Sodium bisulfate – 5 pound of swimming pool/spa PH negative ·2 gallon plastic bucket for anodizing tank ·Power source – 12v car battery charger with minimum 10 amp output and no auto shutoff ·Volt meter and amp meter optional here but I prefer to monitor the process. If charger has an amp meter you can monitor the current draw with that ·Aluminum to make cathode. I used 6061 which for aluminum works the best. ·Aluminum to make frame to hang parts for anode connection. ·Stainless steel screws. ·Anode material – You will need some sort of aluminum to connect to your parts being anodized. It must be aluminum or titanium. This can be a wire or thin flat stock. It is best if aluminum is used to try and use the same alloy as is being anodized. (Note- if aluminum welding wire is used it is important to insure that there are no fluxes in the wire or it will contaminate the anodizing tank.) ·2 electric hot plates ·2 sauce pans 2 to 4 qt (whatever will fit your parts) ·1 pack or container of RIT clothes dye. What ever color you want. ·Thermometer of some sort like a candy thermometer ·Stirring sticks – I used wood dowel rod cut to length ·Rack to hang parts in dye and boil sealing ·Plastic sheeting to protect bench ·Spray bottle for distilled water to rinse parts ·Misc. plastic containers to help with cleaning your parts ·Dish soap or degreaser ·Etch solution (metal brightener) I used Pro-power Acid Cleaner C-24. Contains sulfuric acid, phosphoric acid and hydrofluoric acid. It is highly concentrated and gets diluted 10 to 1. ·Baking soda in case of acid spill ·(optional) Lye or greased lightning sodium hydroxide NaOH (caustic soda) if stripping anodizing off already anodized parts
1)Make a rack to hang your parts from for the anode connection. You will need some sort of aluminum rack to hang your parts from over the anodizing tank. I made one from 6061 aluminum and tapped holes in it then threaded stainless steel screws into it. All parts of your rack if screwed together should have tight connections for good current flow. View attachment 48324
2)Make cathode for in anodizing tank. The cathode can be aluminum or lead. I recommend aluminum because it is easier to work with. The cathode needs to be fashioned that it comes out of the acid solution so that your electrical connection can be hooked to it. The cathode does need to be a specific minimum size per calculations that are to be done based on what you are anodizing. I made mine big enough that no matter what I fit into my 2 gallon bucket the cathode will be big enough. View attachment 48322View attachment 48323
3)Mix anodizing solution. I mixed 5 pound sodium bisulfate (pool ph negative/decreaser) to 2 gallons of distilled water. Remember anytime mixing acid and water it is ALWAYS ADD ACID. Adding water to acid can give bad reaction so you always add the acid to the water. Mix well. I used a wooden dowel rod that I kept just for this purpose. Mixture will be cloudy at first but after a while will settle out and become clear.
4)Prepare your electrical connections. A regular car battery charger works great. It must have a 10 amp minimum output for heavier loads but a smaller one may work for you. I monitor current and voltage in my process. I have setup a volt/amp meter I bought for $16 on eBay. It keeps the more expensive meters away from this process. View attachment 48321
5)Setup your hot plates and pans. Two hot plates are needed because one is used for boiling water after dying and the other is used to keep dye at optimum temperature of 140 degrees. This temperature is what worked best for dye to take without temperature being high enough to start closing/sealing the aluminum. View attachment 48325
6)Prepare your dye. I used one container, 8oz. of dye, to 3 quart of water. The dye can be used over and over again and water can be added as the water evaporates. Dye can be stored for long periods. I saved water jugs to pour the cooled dye back into when done.
7)Make or prepare your anode hangers for connection to your parts, but do not connect them at this time. This can be aluminum or titanium. If aluminum it is best to use the same alloy. This connection/hanger needs to be able to fasten to your part in an area on the part where it is not important to be finished. The connection can be through spring pressure, screw (aluminum only), weld or wire wrapped. Remember the connection through this hanger is where current will flow through so if it is poor the process will not work correctly. If you use aluminum MIG welding wire it must not have flux in it or it will contaminate the process. View attachment 48327View attachment 48328View attachment 48329View attachment 48326
8)Prep your part to be anodized. The part to be anodized must be prepared to what ever degree you want your finish to be. Other words every little scratch or mark will show after anodized. Anodizing is not like painting where it hides small imperfections. Also if you want a shiny anodized finish the part must be polished. A flat/brushed finish will give you exactly that in anodizing. I have found that to get the part perfect for a flat finish I polish it first and then dull it with a lye mix. After preparing your part it must be cleaned thoroughly. Any grease or dirt will ruin the finish and or contaminate your anodizing tank. I first clean with a mix of dish soap and a little Purple Power (degreaser). Scrub the part very good with this mix and make sure the polishing compound is all cleaned off.
9)Connect your hangers to your parts to be anodized.
10)Next I dip it into an acid solution. I use etch solution/metal brightener. Specifically I usePro-power Acid Cleaner C-24. It contains sulfuric acid, phosphoric acid and hydrofluoric acid. It is highly concentrated and gets diluted 10 to 1 with distilled water. I dip it in this mix for 2 to 5 minutes. It will fizz and carry on but that is correct. This will etch the surface slightly and remove any oxidization that might be present. Once removed rinse thoroughly with distilled water. Only use distilled water because of contaminating the part with tap water.
11)Fasten the hangers with parts to your anode rack. Always keep your parts rinsed down with distilled water. Also do not touch the parts with bare hands. Skin oil will contaminate the finish. View attachment 48330
12)Place parts into anodizing tank and make connections. The anode is the positive connection and the cathode is the negative. View attachment 48331
13)At this point I look at the current and voltage readings to make sure things are connected correctly. Small parts or small amount of parts will draw less current than larger parts. There is a whole calculation process to go through for time in anodizing tank. It is based on surface area of the parts. Personally, due to reasons out of my control, I shoot from the hip. Through trial and error I have learned that about 2 hours will do the job for me. The part will get a slight amber color to it. This is evidence of the crystal buildup on the surface. If you have a lot of parts in the tank it will start to heatup. This is bad. The process will not work correctly because it starts to seal the surface as it creates it. I try and keep the tank under 100F. The best way to avoid this is not to overload the tank.
14)Whilethe anodizing process is running, start warming up your dye solution. No higher than 140F. If dye has been stored for a while it needs to be heated to the 140F and stirred good to dissolve the clumped together dye. Also get the distilled water in the sealing pan ready and heating up.
15)Once the anodizing process is complete and ready for dye, rinse the part thoroughly with COLD tap water. Then rinse it good with distilled water.
16)At this point hang the parts in the dye. I remove the parts from the rack I used in the anodizing tank but leave them on their hangers. I have found it easier to inspect each part while dyeing. View attachment 48332
17)Monitor your dyeing process. The dyeing can be stopped at whatever point you desire. I periodically pull a part out and check the shade. The longer in the dye the darker the color.
18)When the dye satisfies you remove parts and thoroughly rinse under tap water.
19)Next hang your parts in the boiling distilled water for 30 minutes. This will seal the surface and lock the dye in. View attachment 48333
20)Once sealing is done polish your part up with clean dry cloth and you are done.
I want to point out again I am in no way an expert in this process. I am a hobbyist. There are calculations to the process which can be found at some of the sites listed below. There are companies, on the internet, that sell kits to do this process and may make it easier for you but I figured I would do some testing before diving in too deep.
good idea regarding the acid i will try that one deff.(i got a pool/spa shop arround the corner )
i copied your post and saved it on my pc it is great stuff
i used to use the same dye but the wife was not so happy with the die residue in her pots
now i use special dye that is usable without heating so i just have one pot left to boil my parts
some other thing i notised that when i used the clothes dye the results on some sorts of aluminium
where far from good
Just out of curiosity were you heating the cloths dyd at all?
And when you were using it did you use the whole container or pack?
I never used the dye you refer to that is a coold process because all the stuff I read lead me to using this type.
The only time the dye did not work correctly is when the anodizing tank was getting to warm due to heavy load in tank?
I learned to keep tank below 100F. The problem was it seemed to seal the surface as it creates it and the dye wouldn't take.
I now have thermal couples in all three, the tank and two pans. The thermal couples go to digital recorders I picked up and it just makes it easy to look down the line and see the temps.
You can see in the first two pics the thermal couples I made for the application. The third pic shows the three temperature controlers in order of my process. The green numbers are just the probe readings at room temp right now (no process going on) and the yellow I just have set for reminders of the max temperature I should hit. They might be a little much but just playin. View attachment 48386View attachment 48387View attachment 48385