Posts: 255
Should also note that Zinc plating does not last very long once it's been exposed to the elements, within a few years time, it will look just like it did prior to plating it. I painted my calipers knowing that it would be easy to touch up whenever needed without full disassembly.
Location: Northern NJ
Posts: 8,579
My VIN: 10757 1st place Concourse 1998
Plating, when exposed to the elements (weather) does deteriorate. If you want to protect the brake calipers you must also consider that they get very hot. There is paint made specifically for the brake calipers that can handle the heat. One place that sells paint in different colors is Eastwood (eastwood.com) for the calipers.
David Teitelbaum
Posts: 1,243
My VIN: 10201
They also got powders for powdercoating available. I'll be ordering powder from them, but sending mine out to a local place to get done the color I want.Originally Posted by David T
Location: Ellensburg, WA
Posts: 190
My VIN: 5510
Lots of great info here!!
Since powder coating seems to be the more durable option, that's what I'll go with on all of the parts that I can. There are a ton of shops around here, so I'll shop around a bit.
Location: Stevens Point,WI
Posts: 2,470
My VIN: 6125
I haven't been around here much lately so I just saw your post.
For the rear half shafts I decided to POR-15 those since the majority of the part would have had to have been masked off for powder coating. I was also concerned about damage to the splines during handling. You can't really see much of the half shafts once installed anyway so it was just a simpler way to go. I didn't want paint or powder on any critical mating surfaces so I had the interior bearing surfaces of the hubs, threaded holes, and inner bushing surfaces on the control links masked before powder coating to not affect the dimensions for press fitment.
I powder coated as many of the other suspension parts that I could since it's more durable than regular paint. Anything that was originally black I had powder coated in black. The aluminum rear hub carriers were originally just raw cast aluminum so I had those done in silver powder coat to prevent the oxidation and corrosion that happened over the years.
For zinc plating I tried to match the original finish of the parts as best as I could. Zinc plating used to use hexavalent chromium conversion coatings which are all but replaced by trivalent chromium coatings today. The color of the conversion coating over the base zinc plating used to be indicative of the thickness of the coating and corrosion protection, IE: clear --> yellow --> green --> black, from least to best. Today the color is usually just a dye additive that doesn't affect the level of corrosion protection. I went through a DMCMW which has an outside company do their re-plating. They advised that the yellow conversion coating is still slightly thicker than clear so for threaded fasteners it was better to go with clear zinc to prevent gumming up the threads and potentially affecting torque / clamp load when reassembling. I opted for clear zinc on pretty much all of the hardware with the exception of a few washers for the hubs.
The hubs from the factory were finished a dark gray phosphate type coating that didn't provide much corrosion protection at all outside of stopping the parts from rusting in open air. I opted to have my hubs yellow zinc plated instead even though it was not the factory original look. I was mainly concerned with preventing rust and the yellow zinc matched the brake calipers and other nearby parts. If I were to do the hubs over again I'd probably have them coated in dacromet or magni coating that can be done in a dull gray that is closer to the factory appearance. I wasn't overly concerned with the exact factory appearance at the time.
There are more options available now for suspension parts than when I did the restoration on my car so I'd probably make some alternate choices if doing the work today. I'd probably go with DPI stainless front upper/lower control arms and save the hassle of stripping and refinishing the factory parts. My lower control arms weren't all that rusty and at the time and there wasn't much for alternatives. Pressing the bushings and ball joints in and out was kind of a pain, especially the bushings on the upper control arms. I ended up fabricating some special spacer plates to avoid crushing the UCA's when reinstalling the bushings.
It's been almost 10 years since I did the work on my car and everything still pretty much looks as it does in those reassembly photos. I've driven through plenty of rain and bad weather but no road salt. The POR on the frame has held up as well with no flaking or adhesion issues.
And good luck on your restoration project! Keep us all posted with some progress photos as you go along.
Last edited by Mark D; 07-20-2020 at 11:31 AM.
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