About Plating and My Engine Bay Cleaning

[mdsalemi]

(Tom--the thread morphed too much.  Time for a new topic.)

Hi Tom,

(We'll be in touch on the plating issue.)

Further to that, understand (most people in the marine industry know this) that zinc plating and the related galvanizing are "sacrificial" coatings specifically designed to wear away. Nearly all boats have a "sacrifical anode" on them so that the seawater (and lake water too) attacks the easy stuff; that's zinc and magnesium before the steel gets attacked.

The sacrifical part needs to wear away completely before the steel gets attacked. The outdrive on my boat, which is powder-coated cast aluminum, still has one of these anodes on it since the zinc or magnesium is more active than aluminum and steel and will corrode away before the steel and aluminum parts on the boat. Many steel towers, such as those for power lines, cell phones, etc. are also experimenting with buried sacrifical anodes to get longer life. (Just wait, soon we'll see the price of zinc and magnesium skyrocket due to unprecedented demand in China...)

There are two good reasons to choose only cadmium plating for parts on our cars: first, we often try to emulate what was originally done. Well, what was originally done was cadmium, not zinc. Second, read the following from BNET:

Cadmium plating has many outstanding qualities that have been difficult to duplicate, the most important being high corrosion resistance. Contrary to the hype, cadmium plating is still easily available and is safely applied by platers. Zinc alloys were developed to provide alternatives to cadmium plating. The zinc alloys all have many excellent features, but none of them seems to be a perfect replacement for cadmium plating.

Cadmium no doubt is poisonous and toxic, but it isn't sacrificial in the same sense as zinc; it will wear away over time but is better than zinc.  Works for me!  In an MBCA Concours, if one is concerned about that, the expert judges can tell zinc from cadmium plating.  It's a different color.  But you can see that for yourself!

While some corrosives (either low pH acids or hi pH caustics) can attack plated parts--acids in particular will eat a zinc coating in a heartbeat--most cleaners one could use in their engine bay are not that hi or lo in pH to make that much of an effect. I don't know of any real reason to use a lo pH cleaning compound in an engine bay, but most detergents or cleaners of any type--save for those with neutral pH--are hi pH. Just like most soaps and shampoos.  If it isn't eating away at your skin it isn't going to eat metal, particularly in the real-world method of cleaning via dampened rag or short sprays followed by rinsing or wiping.  Simple rule of thumb.

You had asked about what I use, and the preferred compound for me, for degreasing is an "organic solvent" a/k/a just plain old mineral spirits on metal parts, and that "oil eater" http://www.oileater.com/ on non-metallic parts. The oil eater is water based so I prefer NOT to use that on metal. Organic solvents have absolutely no affect on plated surfaces, and don't affect automotive painted surfaces much either (think bug and tar remover).

I prefer mineral spirits to industrial degreasers (think trichlorethylene) or brake cleaner (methanol, toluene and acetone blends) which most certainly affect painted surfaces and most plastics. But make no mistake: I use these serious degreasers when necessary.  I don't spray them willy-nilly everywhere, though.  I had some very serious dirt and grease build-up on my bicycle's gear cog last week, and scrubbing with a brush and mineral spirits didn't help too much.  Blasting with a can of trichlorethylene did.  (CRC Industrial Degreaser http://www.crcindustries.com/auto/content/products.aspx  Note they make a whole line of industrial cleaners and most are available at Grainger)

Speaking of cleaning, I had a crack in a stainless steel water tank at my car wash. I removed it and had the crack repaired. Before I put it back, I decided to clean up the tank a bit--I tried all kinds of my cleaners, none did a particularly good job. I tried a wire brush on my drill--while the SS was brushed in the first place, it didn't do as good a job of removing hard-water crust and staining as one might expect...then I pulled out the strong stuff: aluminum brightener/wall cleaner.

A horrifically dangerous brew of hydroflouric; hydrochloric, and sulfuric acids. Mixed up a dilute batch, sprayed it on. Let it sit for a few minutes, neutralized it with hi-pH detergent and then hosed it all off. My goodness--this 18-year old tank looked absolutely brand-spanking new!  Not only clean, but very bright as well.  If I ever have my valve cover off, it will get the same treatment and you can be sure it will look exactly as it popped out of the mold after casting!

I like looking at the Eastwood Catalog, and Griot's Garage as well as anyone, but cleaning methods and compounds and been around a lot longer than these guys have.  My own opinion is that some of the things they sell are overpriced and appeal as much to emotion as science.

While one can certainly feel "safe" washing their car (for those that choose to use soap and water the old fashioned way) with one of Griot's $39.99/gallon+shipping car wash detergents, I'm not convinced this is any better than high quality products such as those from Zymol, Turtle Wax, Eagle One, and others one can get locally at any auto parts store for a lot less money.  You are just removing dirt, for goodness sake!  In scientific terms, you have surfactants, detergent builders, etc, formulated for the type of "dirt" being removed and the type of surface being cleaned, and thus the biggest difference between them are fragrance, color, thickness, foaming action, etc.  "Inactive ingredients".

For example, most hi pH products contain a dilute caustic--some use sodium hydroxide, others potassium.  Most lo-pH products contain a dilute acid--most choose phosphoric, but others contain hydrochloric or glycolic.  There are buffering agents, too: some contain sodium carbonate, others a potassium salt.

They all provide mostly similar actions, thus most car wash soaps commercial or otherwise are basically the same since they are devised and formulated to remove the same kinds of dirt from the same kinds of surfaces.  Just as P&G figured out how to appeal to "housewives" with differentiation of laundry detergent  (Mountain Fresh!  All-Temperature! Now with Bleach Alternative!), some manufacturers have figured out how to appeal to collectible car owners with their products.

The best kind of car wash detergent could be formulated to be basically odorless, colorless and have no foaming action at all.  Those are all added for customer appeal.  The bad converse of that, is you can make a really poor car wash detergent that has lots of foam, looks real thick, smells great, and has a great color, but doesn't do diddly.  A bunch of inactive ingredients that many think are what's at work.  If you don't respect my opinion, that's OK--this is from the chemists at my two main chemical suppliers, Warsaw Chemical and Stone Soap.

If you want to really get your car clean, try the clay bar after you are convinced that the surface is as thoroughly clean as you can get it.  The clay bar (a mainstay of detailers) really gets all the ground in crud out of the paint surface and is really perfect for prep prior to a waxing.  Wax protects your paint like plating protects your steel.  Griot's paint clay and lube kit is about twice the price of your local auto parts store.  You be the judge if the Griot's product is worth the extra money.

My engine bay is generally accepted as nice; after 10,000 miles and 8 years, it doesn't look exactly the same as it did when it came back from the restorer and with each passing mile it becomes a bit harder to maintain.  There was a film made by MB-USA back in the 1978 where they discussed the restoration of the only remaining Steinway [Piano] made USA-built Mercedes, and they had a notable quote: once a restored car gets any time outside; being driven; or on the road, the restoration becomes a de-restoration.  And as time goes on, it is harder and harder to maintain.

[69280sl]

Michael: When your fuel injector lines were plated (cleaned, tumbled, etc.) did they get bent, straightened out, distorted? Did you have to re-configure them?

Also, should the lines be plugged to prevent plating the inside which may later flake off and plug an injector?

Gus
68 280sl

[mdsalemi]

Gus,

When my FI lines were plated, they were done [incorrectly] in zinc with a yellow chromate finish.  They were done locally by a zinc plater used by the restorer in Grand Rapids, Michigan.  They were not bent or distorted in any way.

A couple of years ago I replaced the auto trans filler tube; the originals were yellow cadmium plated.  The new ones were just painted black.  The plater in California http://www.prime-plating.com/ did that and while a bit more substantial than the FI lines, being hand done it wasn't damaged or distorted in any way.

That's an excellent question about the inside; I'd imagine that the inside of the lines are NOT plated, but I don't know that for sure.  Because plating is to protect from corrosion, the inside of the lines would not get corroded under most normal and even abnormal conditions (save for a lot of water in your fuel; than you have bigger problems) so my guess is the inside is not--but it is a question best left to the experts.

[66andBlue]

When I had my injection lines and other parts under the hood CAD plated I asked the shop owner whether I needed to clean or plug them. His answer was "you make sure that you know where they go back in and how to assemble them, we will take care of the rest". And that is exactly what happened, the small parts were "barrel" plated and the long ones on a hanger,  and I am still very happy with the result.  
DeTray Plating in Independence, MO does a lot of CAD plating for the aerospace industry and they do NOT overcharge you!  
Here is the company's web site: http://www.detrayplating.com/ Ask for Jim Pierson, VP.
They do no longer offer any chrome plating.
 
For that I had used ICI-Industrial Chrome Inc in Topeka, KS and again I can recommend them highly: http://www.industrialchrome.com/  Ask for Gary Sack.

[J. Huber]

So here's a question. I am guessing some of you decided to re-cad the various items in your engine bay while the engine is still in there. So can any of you share what items you removed, how difficult all this is for the average owner, etc...? And anyone have a general ballpark (in US) of what the cad-plating will run for those items? There is not an ounce of cad left in my engine bay -- save the new ball sockets and the IP filter...

[Garry]

I like Richard would be interested in that info also.  I have looked at Bob Possel and John Lews engine bay photos with absolute envy and would like to do a clean up and re cad some of the items.
In Oz there is a company called Jane Electroplating Kits at www.janekits.com.au   Has any one had any experience using either theirs or similar types of kits for the job?  Appears to be realtively simple and cheap way of doing it. But as they say if it looks too good to be true!!!

Garry

[Garry]

Sorry I meant James not Richard for info on cad plating.

[mdsalemi]

Guys,

My own opinion is that if you are going to go through the process of plating your engine bay components, do it properly in cadmium.

You will not be able to do this at home with a kit.  Cadmium is extremely toxic, and even if some idiot--and I do mean idiot--were to try this at home, in the USA at least, you could get arrested for child endangerment (if you have kids) and the men in bunny suits would come to clean up your mess while the police haul your a** to jail, while the EPA figures out how much to fine you.  Are we clear on this? http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=preambles&p_id=819

The only kits available are zinc and tin-zinc and these will give you OK looking results but not historically accurate.  Nonetheless there are those that like to do things themselves and these kits are fine for that if you are fine with it too.  There's nothing wrong with tin-zinc plating.  Takes a bit of work to buff up the pieces though...the cad stuff comes back looking beautiful.

The HUGE effort (and thus cost) is in removing your parts for plating; not in the plating itself.  I'd suspect that your entire engine bay could be done in Cadmium for $500 give or take; way less than chrome plating.  Many items are easy (clamps on the overflow tank; top to the transmission filler dipstick) and others very difficult (the trans filler tube; FI lines; all the linkage components.  Lot of the parts are done in a barrel; the main cost is in setting up the barrel, and your order.  What does it cost to add "one more part" to the barrel?  Nil.  The stuff that has to be done by hand (like the carefully formed FI lines) take more time and cost more, but still reasonable.

Just like chrome plating, you need to photographically document each and every piece that comes off, AS IT comes off, so you know HOW to get it back on.  You'd be surprised at how bad your memory might be when faced with dozens of parts and you can't remember which is which.

Jim, the easiest thing for you to do is to assess what you want to do and do it in stages.  If you removed EVERYTHING, you might find it a bit daunting when you see a naked engine bay and a pile of parts.

Alfred's source, DeTray Plating looks like a worthy plater to the one I mentioned.  While these platers often do production plating they generally know how to handle these custom or one-off automotive parts.  While sometimes we live in a bit of a Mercedes vacuum, understand that all the MB's in the world don't add up to just the 1950's era hot rods being restored all the time, so the platers that handle this stuff should be able to help you out.

[66andBlue]

Michael is absolutely correct, taking the parts off and putting them on is where the costs add up unless you do it yourself.  Plating in comparison is cheap, all platers have a minimum charge and all the small parts on our cars together may be within that minimum! Prices for large parts that go on the rack are more difficult to estimate since it is more labor dependent, depends a bit on how much work the shops has at the time, in how much of a hurry you are, etc.  Throw in the cost of shipping your parts to the shop (with lots of insurance included!!) and back and you'll be in the range of what Michael has indicated.

James, IMO it doesn't pay to plate just those things that you can remove with the engine in.  And how far would you go? Take the water pump out or not? Brake and cooling lines out or not?  
If you are somewhat detail oriented then it is not difficult to do this when the engine (together with the automatic transmission) is out. I found it easiest to take a picture of everything before I took it off - well as it turned out, almost everything  :? .  
When I had a batch I would place them all on a sheet and take first a complete picture of the lot and then detail pictures. Then I would print out the pictures and annotate them. After all parts were off and documented that way I delivered them to the plater and when they came back I placed them out again on the prints before installing them.
And still, I had some mystery parts! [:0] Fortunately we have members like Joe and Al who know these cars so well that they didn't remain a mystery for long.

[mdsalemi]

Alfred has got this all 100% correct.

Let me add this: take advantage of our friendship here.  TR (Tom Rose) and I have done two "deals" together that have worked well.

First, we both have Signal Red cars, and when it was time to have my hubcaps painted, HE sent me all of HIS, and I took care of it all here.  There was a savings because once the paint is mixed up and ready to shoot, doing 8 wheel covers isn't much more than 4. (Masking is another story!)

Then we traded: he had some parts cadmium plated last year, and was kind enough and gracious enough to remember a discussion we had some time earlier about a couple of parts I needed to have done, and we added mine to his batch.

Networking and friendships are what we are all about.  Take advantage of this!

[Bob G]

My dad had a lot of spare time prehaps too much in so as to chrome the intire engine bay encluding the oil pan and power  steering pump, radiator recovery bottle and the oil pan guard. too much for me to undue at the moment, Sure it looks nice ,but its not orginal. I sent michael some pictures that prehaps will be in the coffee table book.
I rather my dad left the engine alone, so until it needs a complete engine its going to have to be what it is. the george Barris customization of the disco 1970's.
Be it so putting money were it did not belong now rest on my sholders along with the electrical modifications I so crenge at so often.
but this is  the car he  drove and I first feel for, so now the delima awaits me and my pocket book and weather or not the engine casting become stock again, the electrical Q gagets disapear in its own uniqueness its  still a Mercedes-Benz W113 SL, just not what I had planned for.

Bob Geco
1968 280SL 113044001201906

[mdsalemi]

Bob,

Consider your engine bay a priceless memory of your father and of the times.  At the time he was doing this kind of stuff, all kinds of customization was the rage as you note, and there was little if any thought to historic preservation of what was, realistically, a "driver" car.

I was too young to look under the hoods of cars in the mid-1960's save for watching my Dad do things, and didn't have a clue as to what I was looking at anyway.  But on Long Island in New York, the Pagoda's were all over the place.  Who would have thought to try and preserve them?  Not too many!  They were drivers!

Aside from what your dad did, there are plenty who have plated and polished things incorrectly if historical accuracy is the correctness standard.  There are some lovely photos of an engine bay in the Meredith book complete with high-polish valve cover and other things like it.  Historically correct?  No.  But reflective of the owner's desire for a certain look.

Your father was right in step with the times!

[Douglas]

Bob,

Your father's sensibility towards chroming was shared by the factory--there was a very obscure and not well-documented option for Mercedes unofficially known as the "factory show chrome" package where different pieces of the engine bay were polished to a high gloss, including the valve cover. The late Frank Mallory's 250SL had this option because he saw a Pagoda at the Geneva Auto Show with this level of finish and demanded it on his own car.

[thelews]

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Douglas

Bob,

Your father's sensibility towards chroming was shared by the factory--there was a very obscure and not well-documented option for Mercedes unofficially known as the "factory show chrome" package where different pieces of the engine bay were polished to a high gloss, including the valve cover. The late Frank Mallory's 250SL had this option because he saw a Pagoda at the Geneva Auto Show with this level of finish and demanded it on his own car.
<hr height="1" noshade id="quote"></blockquote id="quote">

These last couple of posts are great.  I do like originality, but also like the look of the polished valve cover that is on my car (previous owner).  MB liked this sort of stuff, so does that qualify as "original bling?"

Bob, I'd leave the chrome as a memorial to your father and an example of the mods of the era.

[TR]

John -- I like the looks of your valve cover (and filler cap) too.  I have three valve covers, and 5 or 6 filler caps, (along with all the other visible aluminum bits & pieces) to play around with in terms of appearance "enhancement".  My plan is to keep the original stuff untouched though.

A question: Are your valve cover & filler cap coated with anything so that they do not oxidize and thereby become dull?

[mdsalemi]

quote:Originally posted by Douglas

Bob,

Your father's sensibility towards chroming was shared by the factory--there was a very obscure and not well-documented option for Mercedes unofficially known as the "factory show chrome" package where different pieces of the engine bay were polished to a high gloss, including the valve cover. The late Frank Mallory's 250SL had this option because he saw a Pagoda at the Geneva Auto Show with this level of finish and demanded it on his own car.

Go to any automotive show (not the one down at Jake's Bar & Grill, but something like the New York Auto Show, or the North American International, etc.) and you'll see:

Chromed engines and display engines
Ditto for suspension assemblies
Show paint (you don't get that kind of paint in a production car)
All manner of details--some subtle, some not so--to draw your eye to the items being displayed.

Combine those details with the bright specular lights of an auto show (think jewelry display case) and everything takes on a magical appearance!

Frank Cozza--Regional Director for the MBCA, also has a Pagoda with the polished valve cover.  It is a not too uncommon bling item that really stands out particularly in a very clean engine bay.

Noted restorer Bob Platz (Precision Autoworks) speaks of this "Show Package" that Douglas talks about in Issue 13, December 1996 of The MERCEDES Collector:

The Show package was one of those non-coded (until the '60's) options that never got into the accessory books.  Unlike the performance sport package, this was essentially an engine bay dress up with chromed linkages, polished alloy parts, and a little more care to paintwork.  In the '50's and '60's Mercedes "highlighted" their cars for the European and American new car shows and literally backed into having to deliver the same look when some enthusiastic customer requested it.  Moreover, the floor samples themselves had to be sold.  And so, today there is collector interest in this distinguishing option.

What would be very interesting is to actually find this on a data card, and a matching car.  I wonder how many were sold like this and were documented?  The polished valve cover is easy (every hot rod here has them!); but chrome linkages and better paint are very expensive--lots of detail hand work.  I wonder what this all cost back then?  Anyone know what happened to Frank Mallory's 250SL?

[thelews]

quote:Originally posted by TR

John -- I like the looks of your valve cover (and filler cap) too.  I have three valve covers, and 5 or 6 filler caps, (along with all the other visible aluminum bits & pieces) to play around with in terms of appearance "enhancement".  My plan is to keep the original stuff untouched though.

A question: Are your valve cover & filler cap coated with anything so that they do not oxidize and thereby become dull?

Thank you

no coating I'm aware of, just Mother's mag and aluminum polish

[Mark280SL]

John,

I looked at your photos, you have a really exceptional looking car, especially the undercarriage and the engine compartment. Seems hard to top, just beautiful.

Did you restore the car or acquire it restored and build on it?

Congrats.


[
[/quote]

[thelews]

quote:Originally posted by Mark280SL

John,

I looked at your photos, you have a really exceptional looking car, especially the undercarriage and the engine compartment. Seems hard to top, just beautiful.

Did you restore the car or acquire it restored and build on it?

Congrats.

Vince Canepa, a member of this forum, owned it for 37 years.  The credit goes to him.  Maybe an extra 5% is added by me, but this is pretty much how I bought it.  150K miles, if you believe it!

[bpossel]

Very nice John!!!
I still cant determine which I like better...  your babies or your garage!?
Bob  

quote:Originally posted by thelews

quote:Originally posted by Mark280SL

John,

I looked at your photos, you have a really exceptional looking car, especially the undercarriage and the engine compartment. Seems hard to top, just beautiful.

Did you restore the car or acquire it restored and build on it?

Congrats.

Vince Canepa, a member of this forum, owned it for 37 years.  The credit goes to him.  Maybe an extra 5% is added by me, but this is pretty much how I bought it.  150K miles, if you believe it!

[wwheeler]

Some more info on plating. Zinc plating alone is indeed attacked by even mild acids. There are chromating solutions for the zinc plate (black, clear/blue and yellow) that form a barrier to resist acid attack. Cadmium coatings are still more corrosion resistant and have the correct color than does chromated zinc. However, A very thin clear coat(diamond coat from Eastwood) can be applied to the chromated zinc to even the odds. Still not concours, but close.

I am gradually restoring my car area by area. My goal is to keep the car running while I eventually repair/restore the entire car. I purchased a zinc plating kit from Caswell plating that works very well. In addition, you can chromate as mentioned above easily for a realistic look. The result is as good as from the platers. This kit is not be confused with tin-zinc plating kits which I found to have poor durabilty.

My plan is to do all of the small hardware and brackets at home with this kit and send the large stuff (like fuel lines and throttle rods) to the platers to be cad plated. The nice thing about plating with the kit, is that I don't have to take everything off at once. You can plate when and how much you want to do. Most platers do have a minimum charge. Since I will eventually replate everything on the car, the price of the kit is easily justified.  

Just another option.

[Garry]

I am with you Wallace,
You have answered my question on the Kits for minor items.  Not wanting to go into Concourse but drive the car regularly, I am looking for a way to plate to prevent corrosion rather than just to show. Clear coating after the process will obvously extend the life to a reasonable level.
As Michael rightly pointed out, Cad plating comes with a whole lot of enviromental issues and there are not many countries left in the world that will allow adhoc plating in the back yard for obvous reasons. My plater who I trust and has done all the chrome on my car over the past three years will usually charge per item starting from around $25 so to do cad plating, which may be a bit cheaper with out all the pollishing, to all the smaller items under the bonnet here in Oz would quickly pass the $1k mark. The other problem is that he usually takes 3-6 weeks to return the items. Its a cost vs time with him.  The longer he takes the less he charges as he does them on an adhoc basis when he can fit them in with his regular work.  Not a good process for keeping the car drivable.

To be able to do bits one or two at a time is what I am looking for so that the car is usable on the sunny days and worked on during the wet winter days we are having now and the kit process for the minor items appears to be the way to go.

Garry

[mdsalemi]

The Caswell kits that Wallace points to, (and Garry refers to) come very highly rated from people who have used them; there are posts in many different automotive restoration forums all over the place about them.  I think those of you who are pretty smart, and try these kits, could put together the requisite chemistry for the second batch a lot less costly than Caswell.

Because it is zinc and only zinc it is accepted to be, "non toxic". However zinc is considered a "heavy metal" and is toxic to the body in a manner similar to lead; do a search and you'll find more about it.  It is prevalent in artisans working with galvanized steel, and also workers who don't take precautions when handling zinc.  At our MBCA tech session a few months ago, we were supposed to have a demo of Rustbusters spray welding which uses zinc, but even being done outside, the demonstrator got cold feet because of the danger of zinc vapors. http://www.youtube.com/watch?v=uV-QPTpJaYo&feature=related http://www.rustbusters.com/  Zinc toxicosis or zinc poisoning is NOTHING like cadmium, but handling zinc does require more precaution than you might imagine.

As Wallace points out a fabulous benefit is being able to do a part at a time, or at your leisure, without the issue of documentation, photography, shipping, the potential for lost parts, etc.  I agree that if your goal is to simply protect the steel parts with a proper looking plating, and nit-picking historical accuracy isn't a concern, than the zinc will do fine.  If you want to do it yourself, it's the only way to go.

Like anything else, however, it isn't a trivial task--go to the Caswell website http://www.caswellplating.com/ and you'll see a link to a review in Hemmings http://www.caswellplating.com/kits/copycad_hmn.pdf   You've got several pails of chemical solutions: hydrochloric acid cleaner; a degreaser; and the zinc chemistry.  You have some hand-work on the parts, either tumbling, wire brushing or bead blasting.  You have "wiring up" all the parts, and then the actual plating (both sides), followed the the chromate wash before your done if you need to color your part.  You need a good power supply.  You need to experiment to get the plating correct and the color correct.  Should this scare you off?  Absolutely not.  BUT, if you think you can take a few parts off your car, (particularly dirty or rusty ones) before dinner, set them a plating while the steak is on the grill, and install them after, all freshly-plated, you might be underestimating the amount of work involved.  In fact, with mixing up the chemicals, prepping the parts, doing the plating, etc. you'll come to understand the initial setup charge for plating; my guess is you would NOT do just one part, but you'd do a few.

Note also, that this kit (or others like it) are zinc electro plating; see the way each part is all wired together on that Hemmings article?  Commercial zinc plating is typically done in a barrel; the parts don't need to be individually handled.  They'll fill the barrel with 10,000 parts.  Costs about the same as that barrel with 10 parts in it.

In addition to highlighting some areas about plating, my goal in making the post was that IF you are TAKING APART your metal components and plan on SENDING THEM OUT for plating, cadmium is still done. I had once received erroneous information that it isn't done; my queries on this site a long time ago, and to some "restoration experts" did not yield ANY names of anyone doing cadmium plating.

You can do this yourself in a kit, as Wallace points out.  You can do anything yourself, too--from body work, to powder coating, to automotive painting.  But if you choose to involve professionals at least you know a couple of them now!

[thelews]

quote:Originally posted by mdsalemi
You can do this yourself in a kit, as Wallace points out.  You can do anything yourself, too--from body work, to powder coating, to automotive painting.

Why would you want to powder coat?

[mdsalemi]

John,

Assuming you meant powder coat yourself (as opposed to the act of powder coating in general) well, I would not want to powder coat--just like plating it involves a bunch of things that in my opinion, are best left to professionals who do this day in day out for their livelyhood and don't often screw up.  But there are those here on our site that do want to do things themselves, everything they possibly can and powder coating is just another thing in that realm...and to that end, firms such as the aforementioned Caswell as well as Eastwood are there to supply the home powder coater with everything they need.  All it takes is $$$.

Personally, I am blessed by having arguably one of the nations's larger and premier custom powder coaters that specializes in custom automotive powder coating http://www.exoticcoatings.com/ just a short drive away.  Considering the toners they have in stock; the reasonable prices they charge, and the quality of the work they do, I wouldn't consider doing this at home--but that's just me.

Some have the room and the wherewithall for pails of chemicals for plating; some also have the the same for powder coat equipment including ovens or baking-lights, and some enjoy the challenge of doing it yourself as well as the satisfaction of a job well done.

John, if you meant powder coat in general, well, it provides a surface that looks exactly like paint, at about the same cost, in the same available colors, but infinitely more durable.  The OEM wheels were originally powder coated, as were many parts.  If one considers re-painting some part (a battery hold down; a wheel; a fuel-pump cage; a suspension part) that can withstand the heat of the curing process, it's a better finish.  But you knew that.

[thelews]

quote:Originally posted by mdsalemi
John, if you meant powder coat in general, well, it provides a surface that looks exactly like paint, at about the same cost, in the same available colors, but infinitely more durable.  The OEM wheels were originally powder coated, as were many parts.  If one considers re-painting some part (a battery hold down; a wheel; a fuel-pump cage; a suspension part) that can withstand the heat of the curing process, it's a better finish.  But you knew that.

I'm not convinced.  I know professionals who would not choose it (based on experience), it is not what the factory did (my 250 SL wheels are powder coated?)and it is not spot repairable for the inevitable wear, damage, etc. that will occur during driving or maintenance.  Today's quality epoxy paints are extremely tough, have a beautiful finish, are easy to spray (rattle cans), require no special equipment and can be scuffed and touched up should a need for repair or freshening occur.  In another car of mine, damage occured to the powder coated front subassembly.  No way to repair it other than repowder coat the whole assembly if a match is desired.  It was redone, but in epoxy paint so that the next time around a scuff, mask and spray while on the car is all it would have needed.

P.S. The previous meticulous owner of my car, refreshed the front sub and components after some cosmetic damage using the factory painting process.

[mdsalemi]

John,

If you don't like powder coat, don't use it.  Simple.

The OEM wheels (with the 108 part number) that came with my 280 were powder coated.  So were the aluminum replacements I installed.  Yes, I had them re-coated.  If you go through the car you'll find quite a few powder coated parts.  Modern cars, even more so.  In fact, a lot of formerly plated parts are now powder coated.  Have a drink to calm you down.

You don't have to like it, and if you choose to refinish things paint is always a viable option.

[thelews]

quote:Originally posted by mdsalemi

John,

If you don't like powder coat, don't use it.  Simple.

The OEM wheels (with the 108 part number) that came with my 280 were powder coated.  So were the aluminum replacements I installed.  Yes, I had them re-coated.  If you go through the car you'll find quite a few powder coated parts.  Modern cars, even more so.  In fact, a lot of formerly plated parts are now powder coated.  Have a drink to calm you down.

You don't have to like it, and if you choose to refinish things paint is always a viable option.

Don't need a drink, Michael, although you're welcome to buy me one anytime. Simply my opinion and experience in an ongoing debate amongst enthusiasts of vintage cars of all brands and models.  Powder coat for components and clear coat for paint are modern methods.  Nothing wrong with them.  I was offering the alternative view for members to consider, especially those seeking originality.  Absolutes of best, only, infinitely, etc. can be misleading.  Modern finishing methods are shades of gray and one should definitely choose what satisfies their judgment best.  Discussion of various viewpoints and shared experiences helps toward this end.

[wwheeler]

Michael,

Your comments about the plating and powder coating were very well put and I completly concur.

[wwheeler]

I have done an appearance comparison between golden cad plating and yellow chromated zinc plating. I just had my throttle linkages and relay support on the firewall professionally replated using golden cadmium. I have also plated many small things at home using a zinc plating kit and then coloring (chromating) to a yellow tint. Here are the appearance differences:

The golden cadmium has a rainbow effect on top of a gold opaque base. The yellow zinc also has a rainbow effect but the gold color is more transparent or clear. The look of the base gold color is the big difference.

I like to apply a thin satin gloss clear (Eastwood)to the plated surface to seal it and prevent fading. This clear will make the plating last a very long time and will be easy to clean. The downside to the clear is that it mutes the rainbow effect on both zinc and cadmium. The good news is that it brings the two types of plating closer in appearance.

As stated earlier, cad is more durable and correct than zinc. Since these linkages were too large for me to plate at home, I had them cad plated. Cad does not cost that much more than professional zinc plating but cannot be done at home because cadmium is highly toxic. However, taking small nuts and bolts to the plater can get expensive in a hurry and is a pain which is why I do them at home. For me, it is a compromise between corectness, durability, price and convienence. I always try to use the same plating system on mating parts so the appearance is consistent.

[Garry]

Hi Wallace,

I am interested in your comparisons as I have purchased a small home Zink Plate kit with chromate and propose to do some of the parts from the engine bay that way rather than fiddle around with a professional plater.
Did you finish off the clear in gloss, mat  or semi gloss/saturn finish and did you use a heat resistant paint?

Garry

[mdsalemi]

quote:Originally posted by wwheeler

I have done an appearance comparison between golden cad plating and yellow chromated zinc plating. I just had my throttle linkages and relay support on the firewall professionally replated using golden cadmium. I have also plated many small things at home using a zinc plating kit and then coloring (chromating) to a yellow tint. Here are the appearance differences:

The golden cadmium has a rainbow effect on top of a gold opaque base. The yellow zinc also has a rainbow effect but the gold color is more transparent or clear. The look of the base gold color is the big difference.

I like to apply a thin satin gloss clear (Eastwood)to the plated surface to seal it and prevent fading. This clear will make the plating last a very long time and will be easy to clean. The downside to the clear is that it mutes the rainbow effect on both zinc and cadmium. The good news is that it brings the two types of plating closer in appearance.

As stated earlier, cad is more durable and correct than zinc. Since these linkages were too large for me to plate at home, I had them cad plated. Cad does not cost that much more than professional zinc plating but cannot be done at home because cadmium is highly toxic. However, taking small nuts and bolts to the plater can get expensive in a hurry and is a pain which is why I do them at home. For me, it is a compromise between corectness, durability, price and convienence. I always try to use the same plating system on mating parts so the appearance is consistent.

Wallace,

It is important to remember--not so much for you but for everyone else without the direct experience either with the chemistry kits you are playing with or the professionals you have used, that the "gold" color applied is not a plating.  It is a reactive "phosphate wash" so to speak, that is created on top of the fresh zinc or cadmium plating, and isn't there for looks but for added protection.

I think that even when pros do it, there are differences in how the coloring looks.  The color comes from whether or not "Trivalent" Chromates are used, or "Hexavalent"; how many times the product is dipped; the thickness of the coating created, and the underlying color of the base plating.

The "gold cadmium" that I had done had not a whit of rainbow look to it; the silver cadmium (clear) was flat, too.  These were from Prime Plating.  But if you look at paint kits from Eastwood that want to mimic gold cadmium plating they are trying to achieve a mottled, rainbow look that you describe.

Check around and you'll see that many platers offer a variety of these protective finishes over their base plating; in addition to the traditional yellow, there's blue, black, olive drab to name a few.

[wwheeler]

Garry,

I used a clear paint from Eastwood called diamond coat(eastwoodco.com)and they have gloss or satin finishes in aerosol or brush-on. This clear is claimed to be good to 350 F. I goes on very thin and isn't noticeable once it is on. It does not have great scratch resistance which is similar to other paints. I used the satin finish and use it on almost all of my plated surfaces to further increase protection from the elements.

Micheal,

I did not ask for anything special when I got the parts plated with golden cad and the part did have a bit of rainbow color. I am not sure which chromate they used. You are correct about the yellow color not being just for appearance. It in fact helps protect the cad or zinc plating from acid attack. Cad, and more so zinc or prone to damage from even the mildest acids (coca-cola). The yellow acts as a shield.

[Longtooth]

Micheal.. I live in CA, SF Bay area, and Cad plating ain't to be found in these here parts that I've been able to find, nor others that are replating engine linkgages and other originally cad plated parts. Maybe CA's and MI's environmental or toxic / hazardous waste laws differ? or are enforced differently?

Yellow zinc chromate is used instead, as you say.  It may be possible to find out of state Cad plating sources... I haven't tried though.

I recently judged some show class, classic MB's, including a couple of W113's and a 300SL Coupe, and while I wasn't on the engine compartment judging team, at the judging rules meeting before hand it was stated that there were to be no deductions for yellow zinc Chromate vs Cad.... and the comment by the lead judge was that in CA it's rare if ever to see actual Cad plating anymore.  Just fyi... deductions for painted or clear-coated plated parts though... an authenticity deduction (50% of available points).  

[Longtooth]

I haven't seen anybody post yet about why MB didn't use highly polished alumimum valve covers, but maybe I missed it.  If not, the reason was and remains heat dissipation.  The non-polished surface emits more heat than polished surfaces... significantly so considering the difference in emitting surface area.  It's part of the W113's engine cooling "system".  Same applies to chrome plating engine compartment parts.. only even moreso.

[mdsalemi]

quote:Originally posted by Longtooth

Micheal.. I live in CA, SF Bay area, and Cad plating ain't to be found in these here parts that I've been able to find, nor others that are replating engine linkgages and other originally cad plated parts. Maybe CA's and MI's environmental or toxic / hazardous waste laws differ? or are enforced differently?

Yellow zinc chromate is used instead, as you say.  It may be possible to find out of state Cad plating sources... I haven't tried though.

I recently judged some show class, classic MB's, including a couple of W113's and a 300SL Coupe, and while I wasn't on the engine compartment judging team, at the judging rules meeting before hand it was stated that there were to be no deductions for yellow zinc Chromate vs Cad.... and the comment by the lead judge was that in CA it's rare if ever to see actual Cad plating anymore.  Just fyi... deductions for painted or clear-coated plated parts though... an authenticity deduction (50% of available points).  

Longtooth,

Most interestingly and coincidentally, contrary to your experience I'm sad to say, the two true cadmium platers I've spoken with and used are in California.

Burbank Plating http://www.burbankplating.com/  and
Prime Plating http://www.prime-plating.com/

[wwheeler]

Longtooth,

That is interesting and good information about the point standard for cad vs. zinc plating. Given the current enviromental positions, that seems fair. I also think that deducting points for clear coating and painted parts where not done by the factory is absolutely correct. Cars that are being judged to that degree, should be held to a higher standard. In my case, I don't intend on having my car judged and am sacrificing originality for longevity.

Thanks for the info!

[Mark280SL]

I just found it very interesting that a polished valve cover will not emit as much heat as a non polished one one. Why is this? Does the polishing compound seal it somehow or the abrasive action of polishing on the metal create a less porus surface that then holds in the heat?

quote:Originally posted by Longtooth

I haven't seen anybody post yet about why MB didn't use highly polished alumimum valve covers, but maybe I missed it.  If not, the reason was and remains heat dissipation.  The non-polished surface emits more heat than polished surfaces... significantly so considering the difference in emitting surface area.  It's part of the W113's engine cooling "system".  Same applies to chrome plating engine compartment parts.. only even moreso.

[thelews]

quote:Originally posted by Mark280SL

I just found it very interesting that a polished valve cover will not emit as much heat as a non polished one one. Why is this? Does the polishing compound seal it somehow or the abrasive action of polishing on the metal create a less porus surface that then holds in the heat?

My valve cover is polished.  In the hottest weather the temp barely rises above 180.

[psmith]

quote:Originally posted by Mark280SL

I just found it very interesting that a polished valve cover will not emit as much heat as a non polished one one. Why is this? Does the polishing compound seal it somehow or the abrasive action of polishing on the metal create a less porus surface that then holds in the heat?

As LT said, the smooth surface has less surface area than the rough one.

[Mark280SL]

I guess I must be thick, how can it have less surface area if it's polished? surface area would not be changed by polishing or anything else for that matter unless what we're saying is polished vs unpolished areas, is that it?

[Rolf]

The smoother the surface the less nooks and crannies it has.Polishing a surface smooths the high points of a surface so the high points become less; therefore less surface.

[thelews]

quote:Originally posted by Rolf

The smoother the surface the less nooks and crannies it has.Polishing a surface smooths the high points of a surface so the high points become less; therefore less surface.

If you had to quantify that percentage of greater surface vs. polished, what would be your guess?  Or, what percentage of surface is polished off of the cover?


By the way, Peter, this is why we use quotes...so we know who is being spoken to and with respect to what issue.  I'm the first to reply to Rolf's comment above.

[Mark280SL]

I thought about that but on an object as small (relatively speaking) as the valve cover that is already very smooth to begin with (at least mine is) I'm surprised that the polishing could reduce the surface area more then an insignificant amount and therefore affect its ability to cast off heat. Live and learn.

quote:Originally posted by Rolf

The smoother the surface the less nooks and crannies it has.Polishing a surface smooths the high points of a surface so the high points become less; therefore less surface.

[Rolf]

I was just making a general statement regarding what Mark had questioned about how an area could haveless surface area if polished. I agree that the surface area on the valve cover, when polished, should not change significantly enough to have any effect on the temp.

[thelews]

quote:Originally posted by Rolf

I was just making a general statement regarding what Mark had questioned about how an area could haveless surface area if polished. I agree that the surface area on the valve cover, when polished, should not change significantly enough to have any effect on the temp.

I appreciate your response and it's pretty much the answer I expected.  What you explained made perfect sense, but from a practical point of view didn't seem significant enough to make a difference in temp.

[Longtooth]

Micheal, I stand corrected re: CA Cadmium plating facilities.  Thank-you for the web-sites.  The local (Santa Clara Co.) facilities have been telling me they had to stop Cad plating due to EPA or Hazardous waste rules... sounds like they meant they couldn't afford to comply in our area.  One of the ones that shows up in NorCal (Santa Clara) on googleing for Cadmium plating actually doesn't do it anymore.  There are a plethora of them in SoCal though, so I guess there's some kind of industry that needs it down there ... marine? air-craft?


Anyway, thanks. I'll have to spend more time looking in our area next time I decide to get some Cad plating done.

[Longtooth]

Regards cooling capacity of a smooth/polished v rough finish, the area of a rough surface is approximately 1.5x (practical) to 2x (idealized) that of a highly polished surface. See attached diagram --- an isoscelese triangle type surface finish would actually have more than 2x the surface area of a smooth (highly polished) finish in the idealized case.  

Furthermore there are 2 types of heat dissipation involved... radiant and convective (i.e. air movement over surface)... in either case (rough or smooth).  However, radiant energy passing from the inside of the metal to the outside is affected by the interface between the internal volume and the external surface.  The more highly reflective the external surface, the more the heat passing from the inside to the external surface is reflected back onto itself.. and less escapes.  This is also true with highly thermally absorbant surfaces vs highly thermally reflective ones.  Thus, black bodies radiate more heat than white bodies.  That is to say that if the external surface is painted black or has a black oxide coating it will radiate more heat than the white surface.... even though the convective dissipation will be the same.


Download Attachment: Surface Area - Rough v Smooth.JPG
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