Yellow Zinc / Cad plating

[rockcrawler]

Some more tool-plating mania...

This time part of my "clutch alignment/gearbox tools". A bit annoying to have to wire wheel them every time I need to use them so decided to plate them. First pic shows the tank with a part almost ready. Second pic is the part after rinsing. You will notice some pitting on the shaft. When plating this means you have to treat the part in acid, no amount of wire wheeling will remove the rust and oxide in the pits. The shinny zinc finish straight out of the tank is a combination of using a brightener in the electrolyte, correct amperage, an equal surface amount of anode zinc to the part being plated and some experience. When you first start experimenting with plating you will probably end up with a dull mouse-grey zinc on your parts. Chromating them like that still leaves them dull and you won't get the rainbow color effect. Instead of tearing your hair out you can polish the parts before chromating, the dull layer is very thin and comes off easily with steel wool, or you can polish them on a loose flap wheel with fine polishing compound if you want an extra shine. Chromate after cleaning the parts. I would not recommend wire wheeling zinc plating.
It takes a few minutes to get the rainbow effect after dipping the parts in chromate, it comes up as the part dries, this can be sped up with a heat gun. Don't use the parts for a couple of days as the chromate is initially soft and comes off easily. For parts that come in contact with brake fluid let them set for two weeks.

 

[Coolerman]

Any long term use data to pass on? How do these parts hold up in the real world?

 

[rockcrawler]

Any long term use data to pass on? How do these parts hold up in the real world?

At least as well as any professionally zinc plated parts as I use standard chemicals as used by the plating industry Coolerman. I am not sure about parts done with kits as I have no experience with them. As a whole, if done correctly, I would say that DIY plating can give a better result as you are in control of the plating process and therefore the plating thickness and plating thickness = plating longevity. I plate at least double the thickness of a standard commercial zinc plate. Also from an aesthetic viewpoint, no zinc plating business is going to polish your parts before plating unless you specifically ask (and pay) for that. Plating is only as good as the finish underneath. These are some of the major reasons why I like to do it myself.

 

['74 UA FJ]

Pretty cool. We do this on an industrial scale where I work. It's not a complicated science, by any means. Good work!

 

[rockcrawler]

Pretty cool. We do this on an industrial scale where I work. It's not a complicated science, by any means. Good work!

Thanks and yep its easy really. The reason I posted these pics and info is that I find that people are generally intimidated by thinking its a hard process... which is funny after seeing the toyota wrecks a lot of people on here turn into showpieces.

 

[pportmd]

The devil is in the details. How good is the Caswell's Copy-Cad manual helping you get the right supplies and describing technical aspects of the process with words/drawings?

 

[rockcrawler]

The devil is in the details. How good is the Caswell's Copy-Cad manual helping you get the right supplies and describing technical aspects of the process with words/drawings?

Not sure if you're asking Adax or me...

I don't have the Caswell manual but from what I know it's pretty comprehensive. I learned the hard way, reading technical information of which most didn't apply to my flea sized setup and by experimentation. For electrolyte I use 120g Ammonium Chloride & 20g Zinc Chloride per liter of water. Zinc plating brightener, replenisher, chromates I get from AED
You can get all of the above from plating suppliers as long as they don't mind dealing in small quantities.
Caswell uses proprietary chemicals as far as I know and won't be of any use to you in that sense.
Here's a pic of a generic tank setup.

As for the mixing of chemicals and how to use them, the supplier should be more than happy to answer any questions you have, as they will differ with supplier.

 

[joeyg1973]

Rockcrawler,

What do you use for power?

 

[rockcrawler]

Rockcrawler,

What do you use for power?

I have several bench power supplies so I just use one of them, but... a "power supply" per the definition of that is not needed for plating only a rectifier. So you could just use a battery charger in that sense however you do need to control the current smoothly. Some people use a series of light bulbs to drop current as a cheap way out but this is too coarse an adjustment. Really you want a power source with adjustable voltage and current. Whatever you choose make sure that it is rated well above what you are going to use. A lot of cheaper power supplies don't take too kindly to running them anywhere near maximum for extended periods of time.

The electrolyte is conductive but also resistive. The resistance depends on what the electrolyte is composed of and what ratio it is mixed at. The more diluted, the more resistive. A very important aspect of plating is anode to cathode distance. The greater the distance the greater the resistance. So with this info you can see that if the plater is careless with his setup and uses no standard with his anode to cathode distance, his plating amperage calculations will just be pie in the sky and results will vary. You want to get the zinc as close to the parts as possible without creating shorting problems. I use one inch as my minimum and don't vary from that much but it really depends on the shape of the part I am plating. I calculate around 120mA per square inch of material to be plated. 20 minutes at that amperage will give you a standard thickness plate, around 0.0002" to 0.0005".

 

[shamuslan]

Dam this I had just about convinced myself that I would send all my plating out to get done.The one thing that worried me about that was I would most likely loose parts in the process and all parts would have to be sent out at once to be cost effective and then I would have a big jigsaw puzzle of bits.But I thought the risk of this would be better than the poor job and stuff around involved in doing it myself with one of these kits.This thread has me thinking again.Is it really that simple?Does the finish stand up ok?The one thing I had trouble with when looking at these kits was working out the amps for a given surface area of a part how did you do this?Your parts do look great and if I can get results like this I might give it a go,I hate sending work out to be done!Thanks for posting

 

[rockcrawler]

Dam this I had just about convinced myself that I would send all my plating out to get done.The one thing that worried me about that was I would most likely lose parts in the process and all parts would have to be sent out at once to be cost effective and then I would have a big jigsaw puzzle of bits.But I thought the risk of this would be better than the poor job and stuff around involved in doing it myself with one of these kits.This thread has me thinking again.Is it really that simple?Does the finish stand up ok?The one thing I had trouble with when looking at these kits was working out the amps for a given surface area of a part how did you do this?Your parts do look great and if I can get results like this I might give it a go,I hate sending work out to be done!Thanks for posting

Yeah the thought of having to get every zinc part to be plated off the truck in one go sent shudders through my spine too. I prefer to work on things as I go along otherwise things can get a bit confusing!

Yes on all your questions. With working out the amperage to use for a given part I just look at the part and figure out roughly the surface area and set my supply to that. Then I monitor the amount of bubbling in the tank and do some fine adjustments if I think it needs it. After a few parts you'll just look at a part and know "that's about blah amp...". Plating is like everything else, the more you do the more confident and proficient you become at it. You are most likely to run into problems with this with small parts on their own, so its best to load the tank with a few parts at a time if they are small. I keep my plating setups to a bare minimum insofar as complexities. I don't use heaters, bubblers or agitators and still manage with no problems. I always lift the parts out of the tank to check on progress and swirl them around a bit in the electrolyte if there's too many bubbles sticking to them. I have pretty much given all the basics techniques and data you need to know in my posts but I am happy to help out with any other questions.

 

[Coolerman]

All of this is very similar to rust removal using electrolysis. There is an electrolyte (water and sodium carbonate), the anode, just a piece of steel or stainless steel, and finally the part or the cathode. Current is supplied by an old battery charger and the amount of current does not matter though excessive hydrogen gas will be generated with high currents. Large parts can take 8-10 amps. Most of the parts on my Cruiser have been de-rusted with this method. You can go here to see my web page about it... Rust Removal

 

[rockcrawler]

Wow that process does a pretty good job! Might have a go at that too. Similar to you I have had previous experience with electrolysis. I guess that's why I jumped into the deep end with zinc plating without a second thought as electrolysis on its own is a pretty simple concept. The difference you will notice with plating is that its very quick compared to other processes so you have to be more attentive. Once you put your part in the tank (it's a good idea to have the circuit powered up before immersing the part) it will only take seconds to get a complete layer of zinc, and you can judge very quickly if the process is set up correctly. You will either see the part going dull or very shinny immediately.

 

[pportmd]

The devil is in the details. How good is the Caswell's Copy-Cad manual helping you get the right supplies and describing technical aspects of the process with words/drawings?

Not sure if you're asking Adax or me....

I was asking ADAX, since he started the topic regarding the Caswell kit. Just curious to know if the supporting documentation (and supplies) that come with the kit would let newbies plate well right off the box without having to go looking for other references to fill in the blanks.

Your comments and drawing were very useful and appreciated, nonetheless. Thanks

 

[rockcrawler]

No problem, and yeah sorry if I've spammed your thread too much Adax, just thought some more encouragement was needed to people that are thinking about taking up plating.

 

[tm7302]

I need to stay off of this website...too many good ideas!!!!

 

[Trollhole]

Just had a bucket of bolts plated.

Cost was $75 for a 5 gallon bucket.

They are not the bright yellow zinc. But they are darn close.

This is about half the stash soorted so far.

 

[Trollhole]

second half

 

[KillerPea]

We're those last 2 batches zinc or cadmium plated??
I've got a batch of bolts to go to the plater next week for cad plating. They are telling me that any bolt above grade 8 has to be re-heat treated for strength. Has anyone else heard this?

 

[Trollhole]

Zinc.