Zinc Plating Subframe/traiiling arms?

[varg]

It seems zinc plating and powdercoating use similar temperatures though. Does one method have the chance of changing the structural integrity of a part over the other? Do you also know whether or not one is more corrosion or durable than the other? I got quotes on powder coating and it was a lot more expensive than I anticipated, a large part of that cost is powder coating. Would a chemical dip change characteristics of a part? (im not familiar with the process so I dont know if heat is used) Seems like using the chemical method would save time and money.

The plating bath temperature will be higher than ambient but nowhere near the temperature of a powdercoating oven. The temperature of neither method will affect the structural integrity of the subframe or trailing arms since they're steel and not sensitive to even worst case scenario powdercoating temperatures. The possibility of hydrogen embrittlement exists though and you would have to talk to your plater about that. Baking a part after plating is a common process to deal with this issue. Zinc plating is not fast, nor is it cheap, especially when you need have something as large as a trailing arm let alone a subframe plated. The chemicals and equipment involved are expensive, and the regulatory hurdles inherent to dealing with toxic chemicals on a commercial scale add to that expense. Prep work is extensive and will be time consuming either way. Yes, places exist that will plate those large parts and large parts are routinely plated on an industrial scale, it isn't even uncommon. The question is does a place that will do it exist near you? I'd go with powdercoating, over plating on cost alone for these large parts, though the powdercoating will likely have to be removed (or not applied) on the inside of the bushing interfaces. With an unlimited budget I'd gladly plate my suspension components, though I'd do research before doing so because I am only familiar with types of plating and plating processes on a surface level. Maybe I'd do chrome like the high end lowrider guys do . As a matter of fact, if you don't already have a place in mind that's who you should ask about having it done. Find a really nice lowrider at a car show and ask the owner or contact a shop that does nice lowriders/show cars and ask about getting suspension parts plated. This reminds me that when I restore my car I will need to find somewhat local plating shop so I can have all of the hardware I remove re-plated, or at least research DIY plating.

[nando]

The real question would be, if you could afford to zinc plate such large pieces (I'm not sure it's even possible, depends on the size of available dip tanks), why would you drive your E30 in the salt where it might matter? I'd just drive a different car I don't care about (and I do).

There's a reason plating is only used on small parts and fasteners, while paint or other less expensive coatings are used elsewhere.

[Shangsta]

It seems zinc plating and powdercoating use similar temperatures though. Does one method have the chance of changing the structural integrity of a part over the other? Do you also know whether or not one is more corrosion or durable than the other? I got quotes on powder coating and it was a lot more expensive than I anticipated, a large part of that cost is powder coating. Would a chemical dip change characteristics of a part? (im not familiar with the process so I dont know if heat is used) Seems like using the chemical method would save time and money.

Why would you zinc plate a subframe and control arms. Like Varg said i dont think it will be cheap to do parts that big. They both will be perfectly fine with powder coating and if thats too expensive then just paint them. The powder coating is going to have no ill effect on these parts and is done all the time. Powder coating will help with corrosion but if you live in an area where salt corrosion is bad then I would recommend giving the car a good underside cleaning once or twice a year to help prevention corrosion from becoming a problem.

[jwest11]

The temperatures involved in powdercoating should be too low to cause issues with most steels, at well under 300°C. Certain Aluminum alloys and treatments are where it can cause an issue. Without getting to into the details, putting the part in an oven at 200°C for a while can basically ruin the heat treatment done to the part to achieve the desired characteristics. No such issue with steels at powdercoating temperatures. Plating those big parts will be very expensive I imagine.

It seems zinc plating and powdercoating use similar temperatures though. Does one method have the chance of changing the structural integrity of a part over the other? Do you also know whether or not one is more corrosion or durable than the other? I got quotes on powder coating and it was a lot more expensive than I anticipated, a large part of that cost is powder coating. Would a chemical dip change characteristics of a part? (im not familiar with the process so I dont know if heat is used) Seems like using the chemical method would save time and money.

[varg]

The temperatures involved in powdercoating should be too low to cause issues with most steels, at well under 300°C. Certain Aluminum alloys and treatments are where it can cause an issue. Without getting to into the details, putting the part in an oven at 200°C for a while can basically ruin the heat treatment done to the part to achieve the desired characteristics. No such issue with steels at powdercoating temperatures. Plating those big parts will be very expensive I imagine.

[jwest11]

Pulled out the rear of my car to clean things up and install new parts. I'm considering getting the subframe and trailing arms powder coated black but the cost is what is making me think about zinc plating them. I've heard about the dangers of reducing the strength but not sure how much of an effect that will actually have since out of the two methods, one uses heat and one uses electricity (i think).

Also, do most plating companies strip the part before hand in a chemical bath or powder coat or does that usually need to be done elsewhere? I'm wondering if getting the parts chemically stripped instead of sandblasted and then powder coated would be a cheaper option. Thinking about the same thing with my brake calipers.

Thanks!