Home Aluminium Anodising Process - Part 1

This is part 1 of 2
Explaining my system for anodizing machined aluminium items.
In this I explain how I clean, prepare anodise and seal some aluminium parts providing a natural finish.
- Part 2 of the video is specific to how I colour dying the the aluminum following the actual anodising
There is a little more information related to the chemical mix ratios and a download for the time calculation spreadsheet I use.
www.hamrx8.com/Home_Anodising....
process.
I have been home anodising aluminium now for 10+ years. I don't propose to be an expert but do achieve some very satisfying results.
During the video I refer to the company Caswell where I purchase various supplies such as the anodising dye/colour that I use.
Their URL is: www.caswellplating.com/
UPDATE:
These days I use titanium tubes to hang the parts, those are the ones that the +Ve clips are connected to. Also as most of the parts being anodised have an M3 or M4 threaded hole somewhere I use short titanium m3 or M4 button head screws to secure the titanium wire. I put a loop on one end of the wire that the screw passes through -----O, this provides a really secure electrical connection and as Titanium is not effected by the acid or the process they can be used over and over again indefinitely just like the titanium wire. I bought the screws and tube on eBay.

[@GaryMcKinnonUFO]

Pre-COVID i used to spend my Saturday nights out, now i'm indoors learning from people such as hamrx8. Saving money, learning more - and no Sunday hangovers! I've watched 5 or 6 aluminium anodising vids now, got the stuff on order to do it myself in about a week (COVID post!). Settling in now for 37 minutes of education :)

[@bizarro20daves]

Happy to say you can still buy sulphuric acid for annodising as a general member of public in Australia

[@shakeelmirza9344]

Extremely useful video ,salute to you, as not much information available.

[@hamrx8]

Thanks :)

[@antymonian2]

One of the best youtoube video I've ever seen.

[@grahamham3398]

Thank you for your encouraging words.

[@ActiveAtom]

Thank you new here to your subscriber base. We like to watch anodizing. Good move on the blind hole conductivity squirt, nice clear anodize coating. Thank you, Lance & Patrick.

[@hamrx8]

Thank you for your comments, glad you liked the videos.

[@isaacfardig371]

great video; good length, everything was explained well, nice touch with music in background.

[@hamrx8]

Thank you for commenting. Interesting some people don't like the music, though it was louder in these videos than usual.

[@keitharentjr7203]

Thank you. Best information I have seen.

[@ilzegomez01]

Such a helpful video. Thanks!

[@hamrx8]

Thank you for commenting. :)

[@mijodo2008]

Excellent setup, very well thought out, good tidy workflows. Thank you for sharing, Cheers from Michael. Australia.

[@hamrx8]

Thanks for commenting.

[@shaunm2208]

Thank you very much a great video

[@CoconutsHD]

RIP to headphone users @20:20. Fantastic setup tho. Very detailed and meticulous. Well Done.

[@AlessioSangalli]

damnit I read too late. hamrx8 for such a high quality video you have made, why not take care of the audio at that section in post-production?

[@frantisekstloukal4388]

Thank you for this video! Helped a lot. I just have a question. What is the ratio of HNO3/HCl in the 5% solution (can you for example use just HCl) ? And do you add any sealant to the sealing process ? Thanks for a answer! Greetings from Czech Republic!

[@hamrx8]

The ratio is 5% Nitric and 5% Hydrochloric Acid to distilled water. I don't add any sealant to the sealing water.

[@girliedog]

Sulfuric acid is one of the most dangerous acids out there, it can etch the light bulbs in the room you are using it in. One small drop on the skin will not cause pain but could create a very deep wound that will appear over night.

[@grahamham3398]

Oh yes totally understand all that. I have been using these acids for well over 50 years and always take the upmost precautions using eye, skin and vapor protection. My setup is not in the house but in my garage that is well ventilated including extraction. Never had any issues like you describe in well over a decade using my current anodising setup. Thank you for commenting.

[@rphghs]

I will need to construct my own tanks for my project as there are no commercially available plastic containers that are large enough. Any advice on acceptable materials as well as glue /sealant for such construction? Thank you for sharing your processes!

[@hamrx8]

Sorry but no I cant help you with that one.

[@shaunm2208]

Thanks for sharing

[@MrShanksta]

So if doing a part that require a 55 gallon drum. The voltage will need to be higher?

[@hamrx8]

Regardless of the volume/size of the container the voltage is constant and the current is set based on the part surface aria being anodised. You need to use a current controlled power supply so you set the current to the value required.

[@martyyates1115]

I"m wanting to anodize some 2''x5' tubing for wind chimes, I'm having a hard time on the Amp and time that i will need. can you help with that? Thanks

[@hamrx8]

You can download an excel file I created for just this purpose from my website. That should help you make the calculations. Also you can contact me further using the Contact Me form. That way we can communicate via email. www.hamrx8.com/Home_Anodising.html

[@martyyates1115]

@@hamrx8 Thank you

[@clarence4735]

What grade titanium wire for hanging do you use?

[@LEO-xo9cz]

You are sealing before Colouring? I was under the impression that dying came before sealing?

[@yonathans.9062]

EXCELLENT VIDEO, VERY EXPLANATORY AND COMPLETE, THANK YOU VERY MUCH FOR UPLOADING IT. I HAVE A QUESTION, COULD THIS METHOD WORK WITH DIFFERENT ALUMINUM ALLOYS? FOR EXAMPLE AN ALUMINUM ALLOY USED TO MANUFACTURE ENGINE CRANKCASES

[@hamrx8]

To my knowledge anodising is not able to be done on Cast aluminium like car parts.

[@NeoFrontierTechnologies]

A very well matured setup. *like*. Do you keep the aluminium plates ( the negatives ) in the H2SO4 solution when you store it until next use ? I understand the negative aluminium plates will not be anodized but will the acid not get to it when the system is not in use ?

[@hamrx8]

I remove and wash first dip the aluminium end -ve plates in a Bicarbonate of Soda solution to neutralize the acid then rinse them in water. Never leaving them in the acid even for overnight. I have been using the same plates for many years. I use Titanium wire and Stainless Steel screws to secure the Titanium wire to the aliminium plates.

[@NeoFrontierTechnologies]

@@hamrx8 That makes sense. Glad to know the plates last long that way. No need for lead then :). When reusing the main anodizing acid bath electrolyte - what kind of maintenance is required on it ?

[@hamrx8]

@@NeoFrontierTechnologies Yes lead is not needed no way. As for maintenance on the acid bath electrolyte. May be if using it a lot and the level drops below what you want just mix enough acid and water at the same ratio and pour it in. But apart from that if you always ensure the parts to be anodised are always really clean and well rinsed then your bath should last for years. In 10 years i have only done a complete bath replacement twice. However I don't use it a lot these days. Oh also always make sure the -ve aluminium plates are clean of any smut or residue before putting them into the bath. After removing them from the bath, neutralizing them and rinsing, I always wipe them with a clean paper towel to remove any loose black smut that will have accumulated in the surface during the anodising process. They should look a dull grey, you will figure all this out as you proceed.

[@janankiersztajn5189]

Thank you for the video! Can the thermometer be placed inside the acid bath? Is it important to use thermometer with plastic parts instead of stainless steel? I guess the same requirement applies to aerator. Thanks!

[@grahamham3398]

It to monitor the acid temperature I only use a temperature sensor that has a plastic probe. I wrap a small amount of lead around the wire to make it sink. As for a stainless steel one, never done that but it might be ok. Yes my aerator is all plastic.

[@janankiersztajn5189]

Thank you! Any hints what product/solution could be used for degreasing bath instead of Caswell SP degreaser? I live in europe and it’s not possible to buy one here.

[@hamrx8]

@@janankiersztajn5189 You could use most cleaning detergents or solvents to clean the parts. I just use Caswell because its easily available for me but when I first started I simply scrubbed the part and soaked it in dishwashing detergent. The amount of degreasing/cleaning all depends the machining oils etc you have used during the machining process of the parts.

[@tonymontana897]

Hello there. It's refreshing to be able to watch a fellow Australian doing this. I am considering doing some anodising work for myself as I am doing a couple of motorcycle restorations. One being a 2001 Kawasaki ZX9R bike, where I would like to restore the top triple clamp. The part is obsolete and so I will have to recondition a spare one I have to make it look factory. I have studied it carefully and it appears that the part was silver anodised, then the top face is machined, (it has the look of being sanded with 240 grit), then it's powder coated in clear sealer. Question. Is there a "silver" colour dye or is the silver colouring simply achieved by virtue of it being in the acid dip ?? If there is a silver dye, is it just one colouring or are there variations ? I want mine to look factory. Other parts that have the same silver anodising include, the gear selector, the rear brake pedal, the front clutch and brake levers and foot pegs to name a few, so it will need to match up. I will visit Caswell and see if I can find a DIY kit that will suit my low scale situation. Thanks for that link. It will be useful. Any advice would be really appreciated. Thanks again mate.

[@hamrx8]

Hi. That's what go me started with anodising, motor bike parts way back when I had bikes. Anyway, I am not aware of any silver dyes, as silver is usually achieved with just anodising and sealing, its the natural aluminium colour. However I believe commercial anodiser's have a process for achieving an almost satin silver chrome like finish but I have never investigated that so don't know. All I have done when I want silver is just not using any colouring. However the degree of silver achieved does depend on the grade of aluminium. Machine grade like 4000 can end up being a light grayish colour where as 6000 grades are the best for a good natural silver aluminium finish.

[@MinakWanda]

Izin bertanya, Kak kenapa proses elektrokimia (proses anodizing) selalu menggunakan larutan asam pekat (H2SO4) ? Kenapa tidak menggunakan air atau larutan basa

[@grahamham3398]

First to translate your question: "Why does the petrochemical process (anodizing process) always use a concentrated acid solution (H2SO4)? Why not use water or alkaline solution." The use of Diluted Sulfuric Acid for anodising is traditionally the most common for both Commercial and Home anodising. This is generally the accepted way of doing it. The acid is diluted to 20% concentration using distilled water by volume. Looked after properly it will last for many years before it needs replacing, depending on the frequency of use. As to the use of just plain water, well nothing would happen anodising would not happen, the aluminium would simply discolor. However when it comes to an Alkaline solution, there is some research and use of this method and a google search does reveal some information of its use for anodising. However thought it may work, I have no personal experience so am unable to comment. I went for the conventional most accepted way of anodising that works. Sulfuric Acid is easily available where I live so that's what I use however I do believe in some countries it may not be easy to obtain in the concentration and purity needed for anodising.

[@MinakWanda]

@@grahamham3398 Thank You for the answer sir🙏

[@nrosei]

Great video- Curious why you rehang the parts. Newbie question: Why not hang them with the titanium wire from the start of the cleaning process?

[@hamrx8]

Good question. I do often secure the parts to the titanium wire from the start especially if it is light and I am securing with a through hole. Heavier parts I like to put the titanium wire in last as during cleaning I want to make sure the hole I am jamming the titanium wire into is clean and flushed out. Hard to do with the titanium wire already in it.

[@macaholik9789]

Hey buddy great video thanks for the info Can metal be anodized ?

[@hamrx8]

Anodising only applies to Aluminium, that's the only metal this process can be performed on.

[@poepflater]

I want to anodise somt 1 inch square tubing maybe 600mm long... can it be done at home? you think? total surface around 1000sq cm I want it yellow.

[@grahamham3398]

Yes technically that could be done at home. You would just need a tank large enough, say 700mm long or 700mm deep. However the thing to consider is that the current needed for just one (1) tube would be 15Amps, you have to account for the outside and inside aria. 15A would be 1 Hour anodising time the current can be reduced proportionately to 7.5A for 2 Hours anodising time. I have never done tube anywhere this length so I am not sure about how well the inside would anodise over that length, if in fact was required. Anyway if you are only needing to do a limited number honestly the cost of the setup would likely outweigh the cost of taking the tubes to a commercial anodizer.

[@poepflater]

@@grahamham3398 yeah I found the calculator... each bar has about 1000sq sm surface. so yeah it will take loads of time or current.

[@josedavidjimeneztrejos6466]

Hello, I am starting my setup for aluminum anodizing and I would like to know what percentages or concentrations are ideal for sulfuric acid and caustic soda

[@grahamham3398]

You will find the answer to that question and a link to download the anodising time spreadsheet on my website page. www.hamrx8.com/Home_Anodising.html There is also a contact me form where you can talk to me directly. www.hamrx8.com/Contact_Me.php

[@chrissaayman1929]

@@grahamham3398 Hi Graham very good enjoy your programme from South Africa

[@m0gga]

Very informative video, thanks for sharing. I would like to attempt some home anodizing however I cannot obtain sulphuric acid online. I do have some ferric chloride etchant which I use in my circuit board production, would this be a suitable alternative? Thanks.

[@hamrx8]

I have seen somewhere of ferric Chloride being used for anodising but myself I have never tried it so unfortunately I cant comment or advise you on that. I know sulfuric acid can be hard to obtain even doing it in person. Fortunately I found a chemical supply company close to where I live that had no problem selling it to me. The only other option is a car battery store. Buying it on-line has all sorts of transport delivery problems and it cant be sent through normal post. Once you do get it it lasts for years, the most recent batch I made up I have been using for over 6 years now.

[@morgan79347]

Very interesting is this a type 2 or type 3?

[@hamrx8]

Its type 2 Sulfuric Acid Anodising.

[@bashkillszombies]

Is there a reason you're using bicarbonate of soda rather than sodium carbonate which is far more alkaline (i.e. washing soda)?

[@hamrx8]

You make a good point, I have no specific reason for using bicarbonate of soda just that's what I started using way back as I had it in the pantry and continue to use it, seems to work fine for the little amount of anodising I do these days. But I take note of your suggestion and would agree Sodium Carbonate has a better chemical combination for the purpose.

[@IDIMDM]

Anything special about the containers you are using for the various stages? They look like ordinary plastic storage boxes. Thanks.

[@grahamham3398]

Yes correct they are standard storage boxes. Never had to replace them in all the years since I started anodising. Just FYI... These days I use titanium tubes to hang the parts, those are the ones that the +Ve clips are connected to. Also as most of the parts being anodised have an M3 or M4 threaded hole somewhere I use short titanium m3 or M4 button head screws to secure the titanium wire. I put a loop on one end of the wire that the screw passes through -----O, this provides a really secure electrical connection and as Titanium is not effected by the acid or the process they can be used over and over again indefinitely just like the titanium wire. I bought the screws and tube on eBay.

[@SatTracker]

Do you make your spreadsheet available? Nice setup.

[@hamrx8]

Sorry for the delay in responding. I have placed the file onto my google drive. The download link is: drive.google.com/open?id=1IMK7QT7RVsX3FIg_5B8ppx3oQtTdZcar

[@blackdog.6398]

I’ve seen people use crafting wire or molding wire , i the crafting section of your hobby store or shop ...even Bailing wire used too hold up your tail pipe ... ... thank you 🙏

[@mohammadyazdanyar8893]

Dear engineer I have a question about Anodic plate in the Anodized bath 1) what is the material of Anodic plate? 2) How to calculat the size of Anodic plate? 3) Can we cover the entire interior of the anodized bath with an anodic plate?

[@grahamham3398]

It is a thin sheet of Aluminium about 0.5mm thick. It does not wear out in fact I haven't changed it for over 6 years. I use titanium screws and wire to make the electrical connection. I didn't use any formula to calculate the size. I just figured it needed to be about the size of each end of the tank. That works fine. I don't see any benefit or reason to cover the entire interior of the acid tank. Nothing i have ever read on the subject suggests to do this. One thing is to always remove and clean the plates when you have finished anodising for the day. If you leave them just sitting in the acid they will develop a black smutty film on their surface that to me i don't like. To clean them I dip them in water with some bicarbonate of soda to neutralize the acid and wipe them clean with paper towel. Cheers Graham

[@sheltonjonathan]

I know it has been a while since you posted this, but what a great video! Thanks! Did you use 6063 T5 aluminum for the cathodes? I’m struggling to find it that thin.

[@bouza96]

Is there any way to know which concentration baths you use in each step? I understand that for the anodizing you use 20% sulfuric but the bicarbonate and sulfuric nitic mix you did not explain

[@hamrx8]

For the Bicarbonate I just take a guess. It’s like a table spoon/500ml. Sulfuric/nitric is 5% of each.

[@bouza96]

@@hamrx8 thanks for te response, how do you calculate the current? How much current per surface area?

[@hamrx8]

@@bouza96 Visit my webpage and you will find the downloadable spreadsheet I created to do just that. www.hamrx8.com/Home_Anodising.html

[@nomadicphotosophy6103]

Hello, I'm trying to replicate your method but something is not clear to me. what is the concentration of the caustic bath? Thank you

[@hamrx8]

I don't measure out the concentration very accurately. But if I were to estimate it would be about 140cc or a Table Spoon to 2L of water. You may vary this depending on the activity you are getting from the submerged parts. You want a nice consistent light bubbling not violent like the solution is boiling.

[@nomadicphotosophy6103]

hamrx8 I did 1kg of soda in 10 liter of water and it’s working well. Thank you!

[@praveshkumar7647]

What is the process of annodising and which chemical is used for annodising on alluminium

[@shakeelmirza9344]

is the same setup required for hard coat anodizing

[@hamrx8]

The basic setup and process is the same for Hard Coat Anodising. However there are additional requirements such as cooling the Sulfuric acid bath to nearly freezing and voltages upwards of 100 volts at an applied current density of 24-36 amps per square foot. Basically I would say that these requirements take the process of home anodising to a new level. Yes it is doable but you would need a far more advanced bath cooling system than I have.

[@qivarebil2149]

Is it really OK to use tap water anywhere in the process, or should You go for deionized water all the way? And; If You use titanium screws in the holes - will the threads be anodized anyway, or will they be blocked? Nice tutorial - thanks for sharing! 👍

[@hamrx8]

Hi. I only use de-ionized water for the Sulfuric Acid Anodising bath. For cleaning I use standard tap water (the tap water where I live is quite clean and low in calcium). For the final part rinse just before placing in the anodising bath I use filtered tap water. I now use titanium screws to secure the titanium wire to the part, wherever the screw and wire make contact with the part tat aria will not be anodised. The surface of anodised aluminium is an electrical insulator so you want to maintain a good electrical contact with the part being anodised throughout the process. This is why you will choose the most less visible location of the part being anodised to attach the wire as there will be a small spot that does not get anodised and if colouring the part that wont colour. I hope this helps :)

[@prashantjadhav9872]

Sir, Which Titanium grade do you use for Titanium wire?

[@hamrx8]

Hi. The packaging does not indicate an actual grade number. However I do know it is specified as being Pure Titanium - Jewelry and Surgical Grade. Its been a number of years since i purchased any so I don't have any links I can share.

[@prashantjadhav9872]

@@hamrx8 Sir, Thank you for reply. We are using Aluminium strips for suspending Components into the bath. It (strips) last for a month. Does Titanium last for long (atleast a year).

[@hamrx8]

@@prashantjadhav9872 I have been using the same Titanium wire for some years now and it has not degraded at all. As such i have not purchased any new wire for nearly 10 years. You don't even have to clean or do anything to the wire between uses even if it does look discolored. These days I also use M3 titanium screws to secure the wire to the part, so much better tan the way I show in the video.

[@ChaosOptional]

Really great content, well explained and relevant. Pity that the music and the washing machine or dryer in the background made it painful at time to listen to. Really looking forward to the next part.

[@hamrx8]

Sorry the music was a bit distracting I will tone it down in future. No washing machine or dryer in background, I think what you are hearing is the aeration pump while anodising, gas and boiling water in kitchen. There is always something running in the background, I think my microphone is just very sensitive and picks it all up. Thanks for your comment I will try to minimize that in the future.

[@ChaosOptional]

@@hamrx8 No Worries, I think you have created perhaps one of the most comprehensive summaries of the process that I have seen on youtube. Looking forward too more.

[@martinbridgewood1610]

Hey Ham. Would you be interested in anodizing 4 parts for me? The parts are approximately 110mm round and 15mm thick? If so how much? Thanks Marty

[@hamrx8]

I would be pleased to help out but I am in Victoria, Australia so that would only be practical if you live near me or at least in Australia.

[@martinbridgewood1610]

@@hamrx8 I'm in Sydney... I can post them down. How much would it be per part to anodize?

[@hamrx8]

@@martinbridgewood1610I have sent you a FB message.

[@mpxz999]

Ultrasonic cleaning just scared the sh*t out of me. Omg did I jump or what lol

[@hamrx8]

Sounds worse on the video that it actually is. Sorry to frighten you.

[@kyriakikiki9950]

Hi🇬🇷 I want to Ask some questions about anodizing how I can contact with you?

[@hamrx8]

Via my website. www.hamrx8.com/Contact_Me.php

[@machinejugaad9296]

what is the process of annodising and which chemical is used for alluminium

[@hamrx8]

Its all explained in my video. Sulfuric Acid is the main chemical for the actual Anodising process.

[@naengineer]

what you guys use for degreasing?

[@hamrx8]

Caswell Aluminum Degreaser Powder caswellplating.com/anodizing-products/anodizing-accessories.html

[@xaviermiranda7829]

I thought the color of the oxidation depended on the current passed through the piece. Can you explain this part better?

[@hamrx8]

The level of current passing through the part along with time simply determines the thickness and hardness of the anodised layer not the colour eg red, blue yellow etc. With some grades of aluminium there is a process to produce a black finish without dying. However for any other colours this is achieved by soaking the freshly anodised part in a special dying solution. The anodising process causes microscopic pours to form on the surface. these pours are like a sponge that absorb the colour dye. After this the part is boiled or sometimes soaked is a solution to seal and close the pours trapping the colour. I hope this helps.

[@xaviermiranda7829]

@@hamrx8 Thank you so much for the insight. In the meanwhile I learned that what i was talking about was niobium/titanium

[@340havoc]

You should make your spreadsheet public!

[@hamrx8]

Yes I am planning to do that along with a short video on using the spread sheet. Next few days should see it done.

[@lessopinion9707]

Thank you!

[@redeyeraptor2998]

I Sh*t you not I’m from the UK and am a member or the Institute of materials finishing… and you have helped me learn more about Anodising than reading there crappy units ever has. Many thanks for your time on this subject maybe have a little go at Zinc plating 😁😉

[@naengineer]

Soo how much amps for one square cm ?

[@hamrx8]

You can download a calculation spread sheet via my website. That will allow you to calculate Squares, Cubes, Circles etc. www.hamrx8.com/Home_Anodising.html

[@jrmitchellj]

Are you a brewer? in reference to your shirt. Ray

[@hamrx8]

Just a shirt I picked up from a place I visited with friends in LA about a year ago when I was visiting.

[@jrmitchellj]

@@hamrx8 I reside jsut north of LA. Ray

[@WayneCook306]

Way to much chat and not enough do!!

[@user-vq9wf9hk8e]

T. H2SO4= (-5°C).

[@ays2013boss]

.I haven't watched your video yet.But every anodizing video on youtube is a pile of garbage

[@hamrx8]

I would agree many anodising videos on KZbin are very ordinary and lacking detail. I hope you find my video useful and a little more enlightening as many have already commented that it is. There is a little more information and a download on my website: www.hamrx8.com/Home_Anodising.html

[@MrDRSNUGGLES007]

Good day Sir. I have watched your video many times. I'm very very interested in this. I have begun to set up my own small lab for this. Please can you get me an email if you don't mind. Love to chat more. Thank you Dario

[@grahamham3398]

Hi. There is a Contact Me form on my website that you can initially use to make contact and initate eMail communication. www.ghqp.com.au

[@YD4GSI]

Di tunggu kunjungan balik nya ya dari Istanto