New to anodizing

[Gunjji]

Hey everyone,
Ive been looking into anodizing for a cpl weeks now. Getting rdy to get the things I need. However Ive read up on sealing and there seems to be two different ways.
1. Using a sealer chemical bath at 180 degrees
2. Just boiling water

Any suggestions/tips from the experts?

Thanks,
Bryan

[sswee]

Re: New to anodizing

It depends on the use of the part as to which is best. The majority of parts I use the nickle acetate sealer. SS

[Gunjji]

Re: New to anodizing

The parts will most likely be dirtbike parts. Some on the engine, some on the shocks and swingarm...

I heard a crockpot is a good choice, most of my parts are small and should be ok in that size tank. Can anyone confirm that the low setting is around 140 and high is 180 degrees or close enough.

The tanks and temp control is the only obstacle I see before I get started.

Thanks

[sswee]

Re: New to anodizing

Beware of cast parts. They use all kinds of mixes to get a good pour, to increase strength and corrosion resistance. Some will anodize OK, some not very well due to smut, and some not at all. You'll need some etch. Caswell's anodize/chrome stripper works good and can be used at room temp. Some deox/desmut. It works best at 110*F. For those kinds of part I would use the nickel acetate sealer.

Crock pots work real well. Temp. range on the ones I've used has been 110* to 180*F. You could get a boil with the lid on. The main problem I had using them was size. I couldn't find one big enough for what I was doing. A handful of candy thermometers are useful to keep an eye on heated tank temps. Only problem is they are glass and you have to watch bumping them on hard parts or thermal shocking them to shatter.

White plastic paint buckets with lid work good for tanks but heating in them is problematic. I use the Caswell 300W ceramic heaters and thermostats. The crock pots will work good if they are big enough for your parts. I've used hot plates and 8, 10, 12 qt stainless stew pots for dyes and water boil seal

[Gunjji]

Re: New to anodizing

Wow,

Thats some good info,

Thanks man

[Gunjji]

Re: New to anodizing

Ok, instead of posting a new topic, I will continue with this one.

Next question is the power source. Ive been thinking of buying a battery charger and a dimmer switch to control the flow. Its the big charger you see in garages with the two wheels.

But then this "3 Amp Constant Current Rectifier" caught my eye and was wondering if this is more suitable for my needs.
The parts I want to anodize are off my dirtbikes. Nothing as big as a swingarm although the tanks Im looking to use would certainly fit a swingarm size. Like a coleman cooler, but a 5 gal bucket would sufice my needs.

Whats the max Sq. Ft this 3 Amp Constant Current Rectifier will properly anodize? And what would that anodize time be?

If I ask any idiot questions, please feel free to smack me around a bit. I learn that way, lol...

Thanks Guys...

[sswee]

Re: New to anodizing

The 3A CC/CV PS will max out on 96" SA at a 4.5A CD. To grow a .5 mil coating would take 80 minutes.

Unless you have the charger, dimmer, and a couple of DMM's, cost wise your better off with the CC/CV PS. It's too bad Caswell doesn't still carry the 20A CC/CV PS. You can find them on the net for around $300 or cheaper on E-bay but you have to make sure it's CC. I started out with the charger and light bulbs, upgraded to the 3A PS then to a 20A PS.

As far as actual use, the CC/CV PS will eliminate alot of problems. Make your calculations for your setting, set your amperage and it does the rest. It automatically compensates for several of the parameters in anodizing.

Another thing overlooked is aeration or agitation of the tank. If you had the bigger PS, you would still have problems on a larger part due to the heat barrier buildup around the part. Aggressive agitation is needed to combat this problem. Tank temp rising beyond acceptable limits can be dealt with by a larger electrolyte volume, AC unit or chiller.

If you have MS Excel download the 720 rule calculator. You can play with it on part sizes, CD's and run times. Any questions on it or if you want to know how to figure everything yourself, just ask.

Chew on this a bit and see what else you want to know. lol
SS

[Gunjji]

Re: New to anodizing

Think this one is good?
PRO-CRAFT RECTIFIERS 10 AMP 110V RECTIFIER
Description: Precision built, duty-duty, solid-state electronic units with a range of power to handle all plating needs. Works by means of the powerstat control, to produce desired voltage.

[sswee]

Re: New to anodizing

No, it's not CC capable. Most all like you want will have two sets of knobs. A coarse and a fine adjustment knob for current and the same for voltage.
SS

[kmbrly]

Re: New to anodizing

I, too, am new to anodizing. I bought the LCD kit and a 20 amp rectifier from Caswell (it might not be listed on the website - call them and ask about it). I anodized a practice bar using it the other night and was very pleased.

I used the sealant that came with the LCD kit. What type of part could be sealed with plain water?

[sswee]

Re: New to anodizing

Parts that will be handled or around food due to so many people having an allergic reaction to nickle.
SS

[Gunjji]

Re: New to anodizing

Hey kmbrly,
Did you dye the part(s)?

And sswee,

Unless you have the charger, dimmer, and a couple of DMM's

What is DMM's? LOL

Although Im new to it and will learn as I go, I want to do it right and easy as possible as far as the PS goes.
If I have a part to anodize that is say 1 Sq ft, I will need 4.5 amps coming from the rectifier for optimum performance correct?
Then the 3 amp recitfier wont be enough, am I correct in this or am I just an idiot?

[sswee]

Re: New to anodizing

DMM = digital multimeter
Usually one to watch you voltage and one for amperage.

I'm going to go technical on you for a second. If you have a flat plate part 1' squared, you will have a surface area (SA) of 288" square by counting both sides. Now to your question. If you have a part with a SA of 144" or 1' squared, to run a CD of 4.5A your PS setting would be 4.5A. That said, if you have a part that will push the limits of your PS, you can drop down to a 3A CD or anywhere in between but it is recommended to not go below a 3A CD. The down side to that is the lower the CD, the longer the run to grow the same thickness coating. And the larger the pores, possibly causing problems if you are trying to match color to a part anodized at a different CD.

At a 4.5A CD, a 3A PS will do a SA of approx. 96" square.
At a 4.5A CD, a 20A PS will do a SA of approx. 640" square.
I am running a 20 gal. tank with an acid pump for agitation and a window unit AC for ambient cooling. When I run enough parts to be pushing 12 to 15 amps through the circuit, the ambient cooling and volume of electrolyte can not dissipate the heat fast enough to maintain the tank temp at an operating level. Just something to consider when looking at the size of the setup you want.
SS

[kmbrly]

Re: New to anodizing

Yes, I dyed the part. I used Caswell's Violet DS, mixed and heated per the instructions. The part came out a dark purple - like Welch's grape juice. I must say that when I anodized the bar, I did not know how long to leave it in the solution. My computer was messed up and I did not have access to the 720 calculator. So, instead of an hour, my part was in there for about 2.5 hours. It must have been o.k., since it took the dye readily.

[sswee]

Re: New to anodizing

kmbrly,
To find the run time without your PC take 720 times the desired coating thickness (from .1 to 1. mil) and divide by the CD used (4.5A normally) to get your time in minutes to run.
SS