"New" S-Caliper Finishes

[Neunelfer]

We've been searching for the perfect S-Caliper finish and it's a tough road to hoe.

S-Calipers were originally cleaned up striaght out of the casting and then chemically cleaned in a dip. After that a layer of anodizing was applied to protect the aluminim and on later models they had a dichromate bath.

After a long chat with wheel Maestro Harvey Weidman we came up with a new process in the anodizing to help replicate the like-new finish.

It's a difficult process on these older calipers as many of them need to be cleaned and buffed deeply to eliminate years of corrosion. In the end, I'm happy with the results.

I know others have been concerned about an "over-restored" finish in the past. Let me know your thoughts...

Starting with the 69-72.8 finish. This is the new clear anodizing:









Here's the later dichromate. We have a color sample on site now so they are matched to the inside (virgin finish) of a damaged factory fluid inlet cover:

[Alan.uk]

Hi Eric,

They look great to me.

Alan

[robmog]

looks much better to me.

[davep]

Very nice! So this is the look of my Versuch replicas?

[Neunelfer]

Thanks Guys... I'm thinking one more grade of edge to them. Just a tad fuzzier. Thoughts on that? Also, the dichromates were just sealed with petroleum jelly before I shot those so... they're a bit duller in real life once that sinks in.

[Grady Clay]

Eric,

My lame (40+ year) recollection is the caliper was basically silver with some coating that had an ever-so-slight tinge to it. The ‘gold’ tinge came about after a little use (heat) and age.

I remember cleaning off the Tectyl (the one-season undercoat) overspray and having to use solvent, not lacquer thinner.

I recall several new (in ’69-’70) owners who ‘cleaned’ the coating off their calipers with lacquer thinner, only to have them look ‘too silver’.

I don’t think they were plaited as the hardware had (starting in ’68) cadmium with chromate conversion. This cad plating was notably different than the current zinc & conversion (now too shiny, too gold).

I suppose the calipers may have had silver anodizing.

I think I may have a couple of OE sets that have been off cars since the early ‘70s. I’ll look.

Best,
Grady

[Flieger]

I like the shiny coating you gave mine. The rough new finish is nice to be lower profile but my shiny ones are still clean after a few years of use and no cleaning. The drit cannot get a grip on the smooth surface.

Either one is better than the cores I sent you.

[Neunelfer]

Dave - That will be the Versuch finish as well.

Grady - All S-Calipers were anodized as follows:

1969 - 1972.8 - Clear anodizing on the 908 casting.
1972.8 - 1976+ - Anodized with a dichromate dip giving them the greenish gold color on a different (almost 910ish) casting.

ATE steel calipers were all zinc plated not cad. We've had NOS calipers tested to verify this while attempting to replicate that finish. Cad, while common on fasteners is not what the calipers used.

The fact is, the factory (steel) calipers had a very light dichromate dip after clear zinc. Over the years the yellowish tint can wear leaving the calipers almost looking silver. 914-6 rear calipers are famous for this. After tearing apart thousands of calipers, I've never seen one that doesn't have yellow zinc on the mating surfaces.

Both of these S-Caliper finishes are matched off factory pieces. Anodized clear and the later with the dichromate.

[MarkS]

[QUOTE=Neunelfer;250815]We've been searching for the perfect S-Caliper finish and it's a tough road to hoe.

Eric, outstanding work and research. By the way from an Iowa born and raised farm boy it's "a tough 'ROW' to hoe"

[Neunelfer]

from an Iowa born and raised farm boy

Oh what do you know! LOL

Learn how more stupider I are day by day!! (but you must admit, roads would be much harder to hoe)

Thanks Mark.