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Technical & Reference Section => Tech and Restoration => Topic started by: Avro on February 22, 2017, 11:59 AM
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I have been messing around with anodising this last few weeks and thought I would share my early results. It was with some trepidation that I embarked on the adventure. You Tube videos make it look so easy and the results perfect; I knew it would not be like that! My apologies to anyone who actually knows what they are doing where anodising is concerned! That said I am happy to make mistakes and have a bit of fun with the process. Here is my set set-up in the kitchen, or rather what I now call 'The Lab' (you can probably guess that I am not married!!):
[attachment=1]
...and here are the first victims, Suntour SCII pedal cages form a set of pedals I am restoring for my Laserlite:
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They have been stripped in a caustic soda solution. I have sanded then with 400 grit, then 800. It is a balancing act I think, how much metal to remove in order to get a reasonable finish whilst maintaining detail. The stamping on the ends is not very deep. After they were sanded I dipped them again to clean them and to remove the more stubborn areas of anodising, in particular where the screws have been. From now on it is rubber glove time. After this they are dipped in a nitric acid solution to to clean off any impurities from the surface of the metal.
Now we come to first major mistake. You have to suspend the item in the anodising tank by aluminium wire. I had read that where the wire touches the item to be anodised there may be left an area where the anodising has not taken. I wanted to avoid this so I just hooked the wire and hung the parts that way ERROR. All that happened was that the the electical connection was no where near good enough and the wire just spark eroded away and the cages fell to the bottom of the tank after a few minutes.
Take two and I wrapped the wire around to give a better connection. As it turns out you need a VERY tight connection in order for the process to work. I ended up crimping the wire tight in the end to avoid the spark eroding, I was thinking sparks and hydrogen are not a great mix. I future I will use nuts and bolts to make the connection, if any one has some M5 or M6 aluminium nuts and bolts I would be grateful for a few.
Anyway, here are the cages in the tank all wired up and bubbling away:
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After an hour I took them out and rinsed them off. They do not look a lot different at this stage, just the metal has a dull lustre to it. On the hob I had a pan with a solution of black dye at 50 degrees centigrade. Plop in go the cages for 20 minutes or so (I have recorded all the timings at every stage so that I can tweek things as I, hopefully, advance). The temperature is kept constant, too cold and more time is needed, too hot and you risk sealing the anodised layer too early:
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When the colour looks about right the cages are dumped into a pan of near boiling water for 1/2 hour or so to seal the dye in.
Here are the results of my very first experiment in anodising:
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Not too shabby although the picture flatters them somewhat. They are a bit patchy in colour but on the whole I was encouraged. I will redo them next week when I have some time off work.
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Nice one Peter! Thanks for sharing this! :daumenhoch:
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Thats amazing results mate..
Nice bit of kit looks expensive but rewarding to do.
You must be single or an understanding missus .
My other half would kill me..
Top work mate..
Cannot wait for the next episode.. fistblump
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Boiling up the awesome sauce :D
Nice job man.
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I have done a little more work on this. I have had a set of Dia Compe MX900 calipers, with centralisers, for some time; originally for my Raleigh Aero Pro. The Aero Pro has now moved on but the calipers are perfect for my Laserlite. However they are raw and no evidence of any anodising what-so-ever. For the Laserlite they have to be black. So into The Lab!
The brake arms have been stripped and sanded with 800 grit, then 1200 then 2000. I then gave them a light polish. Same process as before. The first results were poor, patchy and uneven so I did not seal them and simply dumped them back in the caustic soda solution. I gave them another sanding, careful to try and achieve a consistent finish, back in the etch, back in the nitric acid, rinse, and start again.
It is difficult to calculate the amps required, I am using the fixed amps method, as you need to know the surface area of the parts. I decided to up the amps over what I used for the cages and see what happens.
Here are the brake arms prior to dipping:
[attachment=3]
...and after:
[attachment=1]
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I have not polished these yet but I am thrilled! I think they are going to be good enough to use, I am really rather chuffed.
Hopefully there will be more adventures in anodising to come.
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Nice work Peter :4_17_5:
Always good to see kitchen equipment being abused in the name of restoration :teef:
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Great work! Well done :4_17_5:
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Great work mate...you will likely have a flood of pm's asking for this! It is about time the forum had someone reliable for anno :daumenhoch:
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Good effort... looking pretty good them mate. :daumenhoch:
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Dead good that, A bit of home Alchemy, love it! :daumenhoch:
Always a bit of trial and error involved in this type of thing, think I might have been tempted to use an old knackered part to begin with!
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Brilliant :daumenhoch:
Keep at it and keep posting as you go!
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That's ace :daumenhoch:
Would avoid taking on any work thought. A fickle process and fickle customers does noť a happy avro make :whistle:
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Another dimension :daumenhoch:
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Nice work. This type of restoration work is really rewarding. Reading this makes me want to give it a try myself.
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They look great. :coolsmiley:
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I have six days off work and had planned a spring clean and BMX restoration/build work. I needed the down-time after a hectic few weeks at work and was looking forward to it. My hopes were dashed this morning with a recorded delivery letter from my landlord to leave; two months notice given. I have often wondered if a casual view of my kitchen would instill visions of a meth lab but I have no knowledge of the landlord being in the flat of if he/she is a Rad member (giggles). Truth is I am a private tenant who dare not ask why.
Two months will fly by I know so I will have to look for a place asap, but also look to progress threads I have posted here. This may seem odd to some but the whole BMX thing has become a retreat, an indulgence and something I have enjoyed.
Therefore my hand was forced and, notice the leave letter in hand, I thought lets have a go at those pedal cages! I had already atempted to anodise the cages, my first ever attempt, and the results, were not too shabby. Some very rudementary lessons learned and a lot of experience gained along the way. Since my last post in this thread I had decided to put a lot more effort into preparation work, being that any paint job, or similar work, will always reflect the preparation time put in.
So here goes. This is actually my third attempt with the cages. To recap, the first attempt had the cages arcing with the suspending wire and eventually falling to the bottom of the tank due to erosion. The second attempt was very encouraging although patchy and revealing of underlying finish issues.
I stripped the cages again in caustic soda solution and desmutted for good measure. I then decided to prepare the metal more aggressively than before. I bought a palm (mouse) sander and a plethora of papers to begin the refinishing process, I also bought a plethora of wet and dry papers to work towards a finished patina. I used the papers from p80 to p120 to p240 with the palm sander until most of the scratches were gone or very faint. Deeper scratches, and one cage had several that would have to stay; they were either too deep or traversed stampings. Once a consitent patina was achieved with p240 I moved on to hand sanding with wet and dry, lubricated with water and a tiny amount of fairy liquid. The hand sanding went from p400, to p800, to p1200, to p2000 and finishing with p2500. Hours or work but goal orientated. I decided to leave the cages at p2500 and not polish; thinking this finish looked very consitent and acceptable (deep scratches excepted that to remove would have destoyed the cages).
[attachment=1]
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....so I then connected both cages to a length of aluminium wire and then dipped in to caustic soda solution until a uniform brown/black appearance was evident. Then they were dipped into a nitric acid solution (desmut) where the impurities are removed and the metal surface returned to a uniform aluminium lustre (more dull than what p2500 delivered). Throughly rinsed in de-ionised water and then into the anodising bath.
15 minutes in and the voltage has ramped up to 16.6v maintaining 1.17amps
[attachment=1]
30 minutes in and voltage at 16.3 - 16.6v maintaining 1.17 amps
[attachment=2]
1 hour in and 14.9v (close to optimum) at 1.17 amps; really good fizz from both cages.
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1 hour 15 mins in 16.9v holdign 1.17 amps; suspect one cage connection has eroded and therefore concluded the experiment although, given surface area estimates, still with in tolerance.
[attachment=4]
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Love thread like this, keep it coming :daumenhoch:
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...ok I am having terrible trouble putting pictures where I want them, the system of uploading pictures and then attaching seems out of whack. I will have to give up on the progression of the anodising process, complete with power outputs for the anooraks (like me). I have tried several time now and I just give up. The way you attach a photograph, and the order you upload it, makes no sense. Grrrrrrrrrrrrrrrrrr. May have to try the third persen route and use a hosting site but meh...cross.
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....sorry for the lack of progress photographs, I like to see them so assume others do. The end result is 'puffs out chest, praised mathematics and chemistry, clears throat and declares 'SUCCESS'.
'puffs out chest a little more' the black colour is completely uniform. It is also very hard. I had previously anodised some brake calipers and they looked good but truth is I managed to scratch off the black surface with my nail on the edges of the casting. The coating on the cages is solid, like it should be given it is similar to sapphire.
[attachment=1]
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These are as they have dried out of the final rinse in de-ionised water. Once polished they will look like new. Sorry to sound so triumphant but I am thrilled. I guess I knew it was all about the preparation, and that is where all the time is. It makes no sense financially but the sense of 'omg' is high, at least when you first see the part out of the rinsing water.
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Great work :daumenhoch:
Possibly a daft question, but I thought with anodising that the polishing was done beforehand, won't polishing them now rub the finish off?
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Rubbing down to p2500 is very like polishing by a different name. P2500, and of course even finer papers, is polishing.
You rather prempt my next experiment! I have a set of MX900 calipers that I need to be black (used in earlier experiments) that I have re-finished in the same way as the pedal cages. However, the brake arms are much more complex in shape.
The brake arms were my second victims for experiment, and initially my first success. They looked good but the black finish was superficial on the shape edges. I rubbed down the brake arms through the same process as the pedal cages, coarse with the palm sander and then by hand. However, the contours of the brake arms meant I had to be careful not to soften them. Having rubbed down to p2500 it was still clear that areas immediately after high spots, that is the low spots, where left differently texturally; like when you sand guide coat a car wing or door. I had noticed that when I first anodised the brake arms that the underlying finish had effected the lustre of the anodising. With is in mind I have gone beyond p2500 and polishehed the brake arms starting with Autosol and finshing with Finesse It: the later being what I have used before on car body work.
[attachment=1]
This is a picture of the brake arms after p2500 paper and paste polishing. The finish is not only finer but more consistent as the paste polish is far easier to get to reach the complex contours of the brake arms. With the pedal cages, a consistent finish was achieved with p2500 alone and I felt that any brushed finish effect, if one should remain, would be wholly consistent and therefore acceptable even desirable. As it has turned out the finish to p2500 on the cages is excellent and, yes, a polish will only enhance the finish and give a shine. Hope that helps. I am still learning myself and loving it.
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I only asked because Jay (the lady who used to do a lot of radsters' ano stuff) told me that she had stuff polished before going in the tank. No idea if there was any post-ano polishing done, but just assumed that anything abrasive might fetch it off
Your stuff looks good though, keep it up fistblump
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Polishing beforehand will give a better result no doubt, but polishing is only the abrasive action to a given surface it just depends on the degree of polish. I felt that the pedal cage finish was perfect, a final polish with a 'finishing polish' will only enhance this. The brake arms required a paste polish due to the contours demanding it. I am sure that if I had used a paste polish on the cages they would have been better out of the box as it were, but that was not the deal with those (there were deep scratches that I could not remove as too much metal would be consumed and detail lost).
I have polished the brake arms to a near mirror without loss of detail and expect the results to be good without loss of detail. I am still learning and experimenting.
I read the anodising thread in the stickies and very early on messaged the poster for a price for some anodising but received no reply. I have subsequently read on the forum a little as to the circumstances why this may have been the case. I hasten to add I am no professional, I do this in my kitchen! I am experimenting that is all. The brake arms have been 'polished' and I hope to anodise them in the next few days *crosses fingers*. I am sure it is all about the preparation as you say, same with any finishing work.
Super questions just bear with me, I am having fun and experimenting and improving with every experiment.
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Great work, those cages have come up great. I love stuff like this but have never tried it myself, good on ya for giving it a go :4_17_5:
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Before:
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After:
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Result! Can not help but feel well chuffed *giggles*
Decals as always by Delcals.
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Brilliant result :4_17_5:
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It's threads like these why I love RAD. I love to see people restoring their bikes themselves rather than spending mega bucks on nos parts and tah dah here's another ridiculously expensive build I've bolted together.
Great work mate :daumenhoch:
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^ exactly. I love it! Well done!
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Given that I have to move in 8 weeks time, to where I do not know at the moment, I thought I had better get on with a few more adventures in anodising before starting to pack up. The brake calipers were next up. These were subject to a previous attempt which turned out rather well although the anodised layer was too thin as it turned out. That said, I was very much encouraged by the results. The beauty of these experiments is that they are repeatable given that one can strip the part and start over. I finished the brake calipers as discussed before and moved on to the anodising process proper.
I decided to bolt up the connection using aluminium nuts and bolts (greenhouse fittings as it happens). This proved to be a boon as you can use the wire as a handle to dip the parts and no real use for rubber gloves (a disadvantage if you are that way inclined I guess). As it turned out the bolt up connection was far superior to wrapping the wire, no matter how hard you try to crimp the connection tight. Yes, there are small areas where no anodising takes place (you can control this) but the wire is not consumed at all so no danger of erosion.
http://(http://i1280.photobucket.com/albums/a487/avrolancaster/P1010880_zpsai5aptut.jpg)
I have reread this thread, and the questions asked, and realise some explanation is required on certain points. Polishing before putting the item through the anodising process is crucial. When I refer to rubbing the parts down with ever finer papers that is polishing although not to a super fine grade. The brake calipers were rubbed down, polished, to a finer grade than the pedal cages with paste but only because they demanded it given their profile. Furthermore, the parts I am using are not immaculate, they have scars and imperfections, in some instances they are well used. How do I cope with those? How much material am I prepared to sacrifice to achieve a given finish? The truth is I do not know; although I do know that the better the finish going into the tank the better the result coming out. The variable is the condition of the part and how far you go. I have learnt that much and to err on the side of caution. Although the anodising process is repeatable the preparation is not. When I said 'I have not even polished them yet' I meant that I had not given them a wax polish.
I had planned to anodise some larger items but only if experiments thus far had proved successful. I have a set of cranks and a chain wheel that are currently silver, the cranks for my Bobby Encinas fun bike and the chain wheel for my Laserlite. Those projects will have to go on hold until I move. Both items need a bigger tank, which would be a waste to set up now when it would have to be disposed of shortly after. Incidently I had an interesting parcel delivered a few weeks ago....6 litres of 96% Sulphuric acid! I am still amazed you can order such stuff mail order!
Back to the brake calipers: all prepped and the first batch into the tank. I decided to keep the amps exactly the same as the that used for the pedal cages. I do not know how to work out the surface area of these complex shapes so I am going by a rule of thumb. The first pair of caliper parts went very smoothly, the voltage was extremely consistent throughout at 14.2 volts. Less than with the cages at the same amps. Does this mean that the power needed to maintain 1.17 amps is less for the brake calipers? Presumably so. Is this because they have a smaller surface area or the material is different: I do not have the foggiest.
http://[URL=http://s1280.photobucket.com/user/avrolancaster/media/P1010881_zpsjmo6h8fj.jpg.html](http://i1280.photobucket.com/albums/a487/avrolancaster/P1010881_zpsjmo6h8fj.jpg) (http://s1280.photobucket.com/user/avrolancaster/media/P1010880_zpsai5aptut.jpg.html)
The parts fizzed nicely form the start and continued to do so throughout. Everything look good. Time up and into the dye and then fixed. They looked great! Blimely this is easy!! The other pair of caliper parts were next, exactly the same procedure, everything the same. Ummm, not the same fizz and not the same voltage draw. But everything was the same?? I carried on with the experiment, finished in the tank, put in the dye and had a look. Rubbish. Despite everything apparently the same these came out hardly black at all. Deep breath and start again. I stripped them and scrubbed them in the caustic soda, scrubbed them in the nitric acid and, with the finish looking consisitent, popped them in the anodising tank. I decided to up the amps from 1.17 to 1.25 amps as it is really the only varible I knowingly control (given I am a complete muppet at this). This was inspired, the voltage draw, a little more than the first batch, was conistent throughout and a really good stream of super fine bubbles was observed from the calipers parts. Time up, into dye, have a look, Hell Yeah, and then fix the dye. Voila! a set of MX900 calipers in black fit for any Laserlite!
http://(http://i1280.photobucket.com/albums/a487/avrolancaster/P1010882_zps8qzrvbjh.jpg)
I have infilled the MX logo with acrylic paint, the most slap dash part of the job lacking a steady hand but meh the job is done. All I need to do now it refit the quick release by forming the new rivet, scared about this but we will succeed. (http://s1280.photobucket.com/user/avrolancaster/media/P1010882_zps8qzrvbjh.jpg.html)
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Speak to Steve Animal about re-riveting calipers, he's done a bunch of 'em
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Use titanium wire for connecting parts, it doesn't erode, doesn't need stripping after every use and makes a far better connection.
A much better way of doing it to to use constant voltage rather than constant current, you don't need to **** about working out surface area then. Although you would likely need a better setup with a pump to circulate the electrolyte.
What ratio of acid are you using and what temperature is the electrolyte at?
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Moving house today so my anodising should recommence soon.
Thank you for the input Chris. I read up quite extensively before beginning these experiments and found a concensus that constant amps was the best way? Using constant volts would be easier, and require a more simple set up, but would it be any better? As I have said I am finding my way as best I can and very happy to make mistakes and look stupid!
The electrolyte is at around 20 degrees C. I bought a fishtank heater, thinking I would need one, but this has not been required yet. A fishtank pump was also on my list to buy but I don't think I need it, at least not for my little tank. When I set up the bigger tank then I think I may get a pump. I Suspect that larger parts my harbour more bubbles so agitation will be required, it certainly will do no harm.
I am using 20% acid solution.
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*waves* Right, back in the game.
A few well earned days off work and back into the lab, or as it is now called 'The Man Cave'.
I had planned to ease myself back into the anodising with small parts again. I picked up a Hatta MX100 head set, for my Laserlite, off the Museum recently which was raw with the remnants of gold anodising visible. My plan was to anodise the cups and top nut black. However this will not be possible as the cups have steel inserts to form the bearing surfaces. I will have to paint the headset, never mind.
So, I had to tackle one of the larger items on the list and set up a bigger tank. This is a journey into the unknown as I do not know what difference the larger tank volume and distance between cathodes will make. Anyway, only one way to find out. One fun thing was making the acid solution. Into a 10 litre bucket I put around 7.2 litres of de-ionised water and then, very carefully, added 1.8 litres of 96% sulphuric acid. When you do this you get a scarey roar when the acid hits the water, quite alarming really! My set up is just as before, no changes there.
The first victim was a raw Sugino chainwheel for my Laserlite. As the Laserlite should have a black finished chainwheel with machined finished teeth I had a go at masking. This is done with polyester sticky tape. Here is said chainwheel, sanded, polished and masked, ready to be cleaned and etched.
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In it went into the caustic soda solution for around 5 minutes. If fizzed immediately and very aggressively, I think I have made a stronger solution than before. All was well and the wheel took on a grey-gun metal finish. I forgot to get the nitric acid solution (it can be tricky as nitric acid is for restricted use only) so I had to desmut as best I could by hand in de-ionised water. This is fine but dipping in nitric acid is far, far better, that much I have now learned. Here is the wheel just out of caustic soda solution. The colour change is the imputities sitting on the surface.
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Then into the anodising tank. This is where things were very different from my previous attempts. My acid solution is 3-4% stronger than before and the part started to fizz instantly. I had not observed that before. Also, when the power was turned on, the voltage did not ramp up in the same way at all. I had very accurately worked out the surface area, quite easy this time given the shapes, so set the amps accordingly. The voltage slowly ramped up to 5.3v and stayed there. Before I was seeing voltages typically between 12 and 15v. I do not know why such a low voltage. Something to do with volume of acid or distances between the part and the cathodes I guess. Anyway I let the experiment run for the allotted time. Then into the dye. Then to fix or seal the anodised layer. Before I was using the temperature method where you hold the part in water at around 90 degrees C for 20 minutes or so. This obviously impacted on my electricity bill and is terribly inefficient. So, I tried a chemical that allows fixing at room temperature and it worked fine. It adds a complication as it is partially consumed each time it is used. This alters the ph of the solution and the efficacy of the process. You have to add more chemical to maintain the correct ph, I think this in turn keeps the concentration within parameters but I am no scientist!
Here is the chainwheel out of the dye.
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As you can see the masking failed. Next time I will spend much more time on this element. Not to worry as removed the anodising on the teeth using a fine paint brush and caustic soda solution and, voila, a black Sugino chainwheel with machined teeth detail. I am pleased with it and the job is done.
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Nice work :4_17_5:
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That's a pretty good job, might try that trick on a chain ring I have :daumenhoch:
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I have done a bit more today, parts for my 'Racergoose' aka Bobby Encinas bike.
The Sugino cranks started out as silver anodised, the SR chainwheel was raw. I did not put a lot effort in preparing these, the chainwheel none at all. I am prioritising a couple of other builds and my time is limited. The lack of prep. work does show, also my 10 litre tank was not really big enough to suspend the cranks and you can see where one has been touching the bottom. On the chain wheel you can see a finger print Grrrrr.
Cranks coming out of the caustic soda solution and still smoking:
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...ready for the anodising tank.
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Cranks being cooked:
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Blue cranks:
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Blue chainwheel:
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...oh, and blue fingers :2funny:
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Nice :)
Would you do any anodising for anyone else ?
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Within reason! Small parts like those shown, I hope to do rims and handlebars but need to research a whole lot more and get more experience. After all it gets a little dull redoing the same piece to get experience :idiot2:
If it helps someone with a build, then sure but remember I am working in a mancave in my spare room, I have a job and committments; I am not a professional anodiser!
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Excellent work :4_17_5:
I absolutely love these threads! This is where the forum based sites are so much better than facebook. Great 'how to' guides and threads that people can refer back to. Keep it real, keep it :radbmxsmilie: and long may it continue :)
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Amen ^^^^^
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Awesome work Peter. Great thread ;)
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What an awesome thread. I have always thought wouldnt it be great to have a go but time patience cost. Put it in the to hard basket
well done for having a go and great results, :4_17_5:
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Awesome thread, needs to be a sticky!
Great work mate :daumenhoch: :smitten:
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Awesome thread, needs to be a sticky!
I agree... them XCll's look awesome Peter. :daumenhoch:
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Awesome thread, needs to be a sticky!
I agree... them XCll's look awesome Peter. :daumenhoch:
I'll third that, great thread this :daumenhoch:
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*cheers* and thanks for that. The spare room, sorry Lab, sorry Man Cave, has run out of work on the anodising front. However, I am trying to source dated Tech 3 levers for my Laserlite which may need re-anodising. I have the parts and tools to rebuild the levers, so I should be able to start up soon. Rebuilding the levers presents a new challenge, the rivets are not shouldered, but I am determined.
I know many take a dim few of the restoration of period parts, and I was about to take them on, but nah, all is good. Thanks again, any input is much appreciated.
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Great work .. :4_17_5:
Thread set as Sticky :daumenhoch:
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Blimey, a stickie! I am honoured, and not a little pleased.
More to come I am sure, most importantly a pair of Tech 3 levers for my Laserlite which I will record, warts and all, as they progress.
Thank you agian for the continued interest and encouragement.
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Work on the parts for my Kuwahara Laserlite continues.
I have a nice set of Tech III levers which came to me raw, for the Laserlite they must be black, so a full rebuild and refinish was required.
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The old rivet was ground down to release the lever. I had already ordered a number of rebuild kits from Pork Chop. The kit includes the rivet, unfortunately not shouldered like the caliper rivet, but fine nonetheless, two plastic lever bushes and the adjuster spring and screw. The screw differs from '80's stock but no worries.
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Here are the parts prepped for the chemical cleaning and anodising. I have invested in a small bench grinder with polishing mops which has made things a little easier. That said, the lever bodies were difficult to get a good finish on. The metal appears to be very soft and also seemed to etch very readily which meant a final bright finish would be tricky. This is in direct contrast with the levers themselves which are a gift.
[attachment=4]
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I have also invested in titanium wire. This should improve the electrial connections and eliminate any risk of spark erosion. The wire is also very much stiffer so easier to suspend parts from and keep them apart once in the tank.
[attachment=5]
After dipping in Caustic Soda and Nitric Acid it is into the anodising tank:
[attachment=1]
All was as before and here are the parts out of the tank, one of the bodies was patchy and I do not know why. I did not have the heart to redo it so I dusted it with paint, a cheat I know but the bodies were awkward from the start and I deserve a break!
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All back together, rivet remade and not too shabby.
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As luck would have it I came across a 44T Sugino chainwheel at a really good price recently, it had already been polished so all the better for anodising....or so I thought.
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The metal looked so good that all I did was chemically clean in caustic soda and nitric acid before rinsing in deionised water, then another go at masking, and then into the anodising tank.
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The anodising looked perfect, super fine streams of bubbles from every which way. Pah! Masking failed again but the anodised black looked the beans.
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So, yet again, I had to clean the teeth with a fine brush and caustic soda. I am beginning to think that the masking is more complex than I thought, more research will follow. The end result is good although, given the shiney and near mirror on the metal, I was surprised by the blemishes. Serves me right for not hand preparing. That said, I am pleased and the Kuwahara will have it's 44T chainwheel. Maybe the 43T anodised in an earlier (and more successful) experiment will do for my Tioga Rhino Charge? I was hoping to fit a CD Tioga chainwheel but have only found concrete evidence that these are 1986 on?
[attachment=4]
I could always re-anodise the 43T to another colour if one were needed?
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Might be worth trying artists masking fluid (like a natural liquid rubber) or copidex glue. Both should peal off once you are done and should resist the anno
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I had wondered about that only this morning. I do have some 'Liquid Mask' (stuff you use on the cockpit glass or windscreens on models) that I thought would give a try. The bottle gives no clue to the contents but is smells like old inner tube. I would have to do a blind test in to see if the acid reduces the mask in any way. The mask just has to resist the anodising process and nothing to do with the dying phase.
Thanks for the input, it is good to hear peoples' thoughts along the same lines particularly when I was only discussing it earlier with my girlfriend here not 5 hours ago.
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...the current rarely goes above 1.64 amps
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This is a cathartic post. I was never happy with the 44T Sugino chainwheel. I wished I had prepared the surface myself rather than assuming that the polished surface as received was good enough. When I stripped the anodising from the teeth I had a few mishaps which required touching in etc etc. Needless to say it bothered me.
I decided to do it again. However it was not that straight forward. I ended up doing it nine times again! The anodising and/or dying phases kept failing. I tried this and that but still pants. Deep breath and remembering that winners never quit and quitters never win, I perservered. For some unknown reason attempt number nine was super, possibly my best result ever.
I had tried liquid mask on the teeth but it too failed a couple of times so I decided to anodise the whole thing and mask later to remove the excess. Result. Cathartic as I said.
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MX900's from raw to blue.
I had to redo one caliper as the process completely failed but other than that they turned out lush.
I have changed the way I mount parts for the anodising tank. I now effectively make frames from nuts and bolts. The change has proved very effective.
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I bought this MX900 at MK17 for the princely sum of £25, bargain.
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First it is stripped down and cleaned with a tooth brush and detergent, I don't want to pollute my deep cleaning solutions with oil and grime. This is what they caliper arms look like after stripping in caustic soda and then scrubbed in a nitric acid solution, this is as raw as you can get the aluminium.
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The calipers are then hand polished with pastes, starting with Autosol and finishing with Peek. I then polish with a dremmel and my little bench grinder which is dedicated to polishing. I went straight to the finishing compound. I decided to try a red this time, the colour is called 'Fiery Red'. They are not perfect, I actually forgot a final dipping stage but the results are still pretty nice. I really get the feeling that I am getting somewhere with anodising now. The blue calipers I did before have really encouraged me.
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They look great! :daumenhoch:
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Hi Avro, Been following this thread from the start and just came back today and was chuffed to see it was a sticky :4_17_5:
I enjoyed the posting of your failures and obviously your successes! I love this kind of work and I work in research myself. So you got me on the track of having a go myself but have hit a brick wall and wondered if you may be able to help? I have everything set up and go through all the prosesses but when I take the piece out of the dye tank and put it into the sealer tank, the dye just falls off? I have tried various voltages/ampage/times but to no avail. Any help would be greatly appreciated. :daumenhoch:
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If virtually all the dye 'falls off' when put into the sealer then the anodising itself has failed. It can be incredibly frustrating. The blue calipers I did for Sleag40's Rickman were an example of this. Both sets of caliper arms were mounted in exactly the same way, connected to the same power source and anodised in the same bath. Both put into the same dye bath for the same time and at the same temperature. One pair of caliper arms came out lush, the other pair completely failed.
I have recently bought a length of aluminium studding which I have cut to various lengths. These lengths of studding are now my frames from which the parts are mounted. It is a further improvement, all to get the electrical connection as perfect as possible. What I would really like to find are cone shaped nuts that could be used against the part to be anodised (imagine the tapered end fitting into a drilling). This would do away with the small areas where no anodising takes place as a nut has been hard against the object.
I think titanium wire is a must, it was a suggestion made by a member on this forum that was golden. Aluminium just is not up to the job, too prone to deteriorate and too prone to spark erode.
To get going start by using black and seal the part in the dye solution, that is after the dying phase raise the temperature of that solution to 90 degrees for 45 minutes of so without ever removing the item from the solution. It will impact your electricity bill but worth it to gain confidence and experience. Most of my early attempts were done in this way and I did get good results eventually. Back to Sleag40's caliper arms, as one caliper arm was really good I decided to try to match it rather than start both sets of arms from scratch. After 20 minutes in the dye bath it was clear that they were a lighter in colour, this would only be made worse when put into sealer. I quickly decided to do the black trick and left the arms in the dye and ramped the temperature up to 90 degrees, the idea being to force more dye in and seal it in one operation. Worked a charm and both calipers looked identical.
It was only with later attempts that I used the chemical sealer, obviously desirable due to no energy cost. I make a fresh solution after every couple of runs.
Perhaps if you tell me what you are trying to anodise I can give you my times if the items are comparable? I keep a log book of all my attempts with times, amps, volts and temperature.
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Hi Avro,
Cheers for your reply, I will let you know where I’m at. The rig is set up at my place of work and its my little my project. I work for a research company and a lot of parts I create need anodizing, so my boss said let’s make a rig up and do it ourselves. (He has no problem with me doing my bike parts either). Probably invested £800 in it so far, after constant failure, my boss has given up on the idea but I am patient and don’t give in easily ha,ha.
I have made a number of frames for suspending the parts, I am using aluminium welding rods to connect the test pieces, all fixings are bolted and have had no sparks or poor connections that I know of so far. I will need to look into the fixings you talk of too, once I get onto doing proper parts! So far I have placed nothing more than a flat piece of 2mm thick aluminium (12”Sq surface area) into the tanks.
The tanks I have are all heated: Degrease, acid wash, caustic acid, Sulfuric/water (Anno tank), dye and sealer tank. I then have De-smut and rinse sprays.
I am going to try and do the high temp dye/seal method you mention. This seems to make perfect sense. I need to order more dye to try this as my sealer tank is quite large and the dye tank is much smaller. Electricity cost is not a problem, as that’s all included in the rent for the workshop we have ;D
Thanks again for your help, let me know if its better to PM you instead of clogging up your thread. :daumenhoch:
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Great work mate. Might need you sometime soon if you fancy a bit of work. A few bits and pieces.👍🏻
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Anodising is about to re-start at my place. Bigger tank for bigger parts (and an even bigger tank waiting in the wings). Fingers crossed I can repeat my earlier successes.
Here is the new, bigger station:
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The left hand bucket is just water for rinsing the parts, this has to be done after each stage to avoid contaminating subsequent tanks. The middle bucket is a solution of caustic soda, the stuff you use for drains and oven cleaning. It is to clean the parts and strip any exisitng anodising from them. The bucket on the right is a solution of Nitric acid (it is actually a pre-made solution which I further dilute). This super cleans the parts and strips away any impurities from the base metal. The grey container is my new 20 litre anodising tank. It is filled with a solution of Sulphuric acid to a concentration of around 15% made from these liquids:
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All are filled and ready to go; I can not wait!
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...and in the interests of trying progress and improve my work I am adding aeration to the anodising tank. I did not think this was necessary with the small parts so I never bothered. This time I am going in equipped! Fish tank pump, check valve (thinking that siphoning battery acid into the pump would not end well), air line, connectors and a modular aeration system fistblump
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How I hope it will look, and stay, in the tank..
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Cooking with gas now. In a similar vein I have a fish tank heater, I bought this right at the beginning. but as the tank was pretty much at room temperature anyway I never used it. Maybe I will try but if anything I need cooling not heating, joke in there somewhere...
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Great skills mate..
Love the random decals everywhere fistblump
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My new set-up is working great, better than I had ever hoped for.
Recently a wanted ad. popped up that prompted me to have a go with a seat post clamp, not only that but in gold (a colour I have been itching to do from the start). I stripped a black Suntour clamp I have had for a while now, black is easy to redo so no biggy, and set about anodising it.
Here is is stripped, prepped and on a jig:
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In the anodising bath:
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Out of the dye and sealing baths:
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Finished product:
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Turned out really nice, better than I had hoped! Lovely.
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Nice work Peter... looks the business that mate. :daumenhoch:
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I have been very busy in the anodising spare bedroom, soon to be small corner of a workshop maybe, for a while now. One of the projects is a set of Shimano DX cranks, one of two sets I have both of which need work. This set came via the Museum at at a reasonable price (hard to say what is reasonable but very much the lower end of any sales data, in fact considerably lower if one talks to the seller; a hit or miss affair but worth a try)...
Before:
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After:
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..more if interested: