To Plate, or Not To Plate?

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Dennis Vogel
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To Plate, or Not To Plate?

#1 Post by Dennis Vogel »

Are there any external engine components that are not meant to be plated, other than the obvious tin that gets painted? I'm preparing to send of my pile-O-parts to Van Nuys. Most are nuts, bolts and washers that I plan to have done in clear zinc (i.e. silver). There are a few items that are question marks to me, and I'm not seeing a coating noted in the parts catalog:
  • Oil sump cover plate with magnet
  • Oil drain plug
  • Fuel lines
  • Fuel pump fittings
  • Crankshaft pulley
  • Case studs
  • Head studs
On a related note, is there a recommended thickness that I should communicate to the plater? I understand that tolerances are relatively tight, and too much coating could affect torquing.

Thank you.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

Erik Thomas
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Re: To Plate, or Not To Plate?

#2 Post by Erik Thomas »

Dennis: With zinc plating I doubt you will have tolerance problems. The old zinc plating is not clear, it is called "white zinc" and is a bit more opaque and less blue than "clear" zinc. If in doubt, run a die over the threads before install.

When you paint over zinc plating, you need to scuff it well with something, either fine sandpaper or Scotchbrite pad. I am not sure about the oil sump plate, but the rest of the parts would rate zinc plating, in my humble opinion.

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Ron LaDow
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Re: To Plate, or Not To Plate?

#3 Post by Ron LaDow »

I would not plate the sump cove unless you are going to R&R the magnet.
Nor would I plate (torqued) studs; there's always the chance of H-embrittlement unless they are baked.
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Erik Thomas
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Re: To Plate, or Not To Plate?

#4 Post by Erik Thomas »

Ron:

I am not sure that Hydrogen embrittlement is a factor with zinc plating, as it is with chrome. Zinc plating is softer than the parent material. A a safeguard, one could bake the new parts in the wife's oven for 4 hours at 350 like I would.

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Ron LaDow
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Re: To Plate, or Not To Plate?

#5 Post by Ron LaDow »

"During Zinc Plating and Cadmium Plating, Hydrogen can diffuse into base metals making them more brittle. Some engineering specifications on particular metallic components demand a stress relieving process as a step in the electroplating service."
https://heplating.com/plating-process-toronto/

And:
"It is readily removed from the metal lattice by baking the product immediately after plating."
https://advancedplatingtech.com/technic ... prevented/
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Juha Vane
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Re: To Plate, or Not To Plate?

#6 Post by Juha Vane »

Also, don't plate the washers, specially the wave washers, they probably crack.
KTF,

Juha Vane
Finland

'59 308
'63 356
'85 911

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Dennis Vogel
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Re: To Plate, or Not To Plate?

#7 Post by Dennis Vogel »

Ron LaDow wrote: Wed Jun 26, 2019 8:31 pm I would not plate the sump cove unless you are going to R&R the magnet.
Then what to do with it? Paint the outside? I have to do something with it as I can see it has started to rust since I've cleaned it.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

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Dennis Vogel
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Re: To Plate, or Not To Plate?

#8 Post by Dennis Vogel »

Juha Vane wrote: Thu Jun 27, 2019 1:19 am Also, don't plate the washers, specially the wave washers, they probably crack.
If you don't plate the washers, are you just tossing them and using new ones?
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

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Dennis Vogel
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Re: To Plate, or Not To Plate?

#9 Post by Dennis Vogel »

Erik Thomas wrote: Wed Jun 26, 2019 5:51 pm The old zinc plating is not clear, it is called "white zinc" and is a bit more opaque and less blue than "clear" zinc.
Thanks for the heads up on this. I have read a lot of plating threads, and they all seem to use "clear" and "silver" interchangeably. Now that I look at the Van Nuys Plating site, I see they list clear, blue, yellow, black Zinc chromate.

I continue to be overwhelmed by the subtleties, inconsistency, and choice of plating. Analysis paralysis on my part at this stage.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

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Juha Vane
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Re: To Plate, or Not To Plate?

#10 Post by Juha Vane »

Use new wave washers and use the old washers for crankcase thru bolts and head nuts. Don’t plate any of these. I plated as
I didn’t know the valve cover springs and they are fine.
KTF,

Juha Vane
Finland

'59 308
'63 356
'85 911

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Wes Bender
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Re: To Plate, or Not To Plate?

#11 Post by Wes Bender »

Dennis Vogel wrote: Fri Jun 28, 2019 11:30 am
Ron LaDow wrote: Wed Jun 26, 2019 8:31 pm I would not plate the sump cove unless you are going to R&R the magnet.
Then what to do with it? Paint the outside? I have to do something with it as I can see it has started to rust since I've cleaned it.
Paint the exposed side satin black or have it powder coated. It shouldn't be left bare or plated.
Some days it's just not worth chewing through the restraints.....

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Dennis Vogel
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Re: To Plate, or Not To Plate?

#12 Post by Dennis Vogel »

Are components like the Oil Distribution fitting meant to be plated? #44 in the attached image.
OilDistributionFitting.png
OilDistributionFitting.png (113.16 KiB) Viewed 2817 times
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

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Ron LaDow
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Re: To Plate, or Not To Plate?

#13 Post by Ron LaDow »

#44 is aluminum; no plating required. I plate 40,45 and 46.
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Juha Vane
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Re: To Plate, or Not To Plate?

#14 Post by Juha Vane »

Check very carefully #40 and #46. Thesee are drilled thru and also have holes in the side. If these have been tightened too much, they can break. See if the holes in the side are perfectly round. If elongated, buy new parts.
KTF,

Juha Vane
Finland

'59 308
'63 356
'85 911

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