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resto4u
02-07-2021, 05:15 PM
Does anyone know where i can get my 67 camaro disc brake backing plates hot dip galvanized. All the places i have found will not do small pieces or just a few pieces.

Too Many Projects
02-07-2021, 05:57 PM
From the "Introducing Rats Nest" thread...
Shout out to Mike Gibbons @ Brake Restoration for re-plating my original caliper brackets and dust shields.
https://www.yenko.net/forum/attachment.php?attachmentid=181136&stc=1&d=1608164605

Postsedan
02-07-2021, 06:23 PM
Steve Gregori obviously sold the business to the Right Guy :)

Dan

enio45
02-14-2021, 02:49 PM
they do hot dip galvanizing??

R68GTO
02-14-2021, 09:19 PM
The backing plates are zinc plated. Hot dip galvanizing is a much different process....I'm not aware of anyone that does that in small part type batches. HDG is found on floor pan plugs, wire way covers, and gas tanks on 69's.

68camaroz28
02-15-2021, 12:04 AM
Mike has carried the torch to one very high elevation and is one great individual to boot. Thanks for sharing.....

RPOLS3
02-17-2021, 12:14 AM
I am in the process of getting my original brake backing shields hot dip galvanized - will advise when complete. Not many places that even do this anymore and they all are large commercial operations that do not have the capacity to handle our kind of piece work as previously noted. I'm using up a favor with a local ornamental steel supplier I do business with. Hoping it all plays out.

Lynn
02-17-2021, 12:58 AM
Totally respect your decision to go with HDG, but hope you realize that is not the finish that was on them from the factory.

As stated in post number 5, they were zinc plated.

RPOLS3
02-17-2021, 12:04 PM
Totally respect your decision to go with HDG, but hope you realize that is not the finish that was on them from the factory.

As stated in post number 5, they were zinc plated.

Respectfully disagree Lynn

I think post #5 stated that he chose to have his zinc plated and that is what is shown in his picture. Upon cleaning mine they are clearly galvanized. This has been confirmed by others here as well.

SS427
02-17-2021, 12:55 PM
Backing plates were galvanized from the factory originally, not zinc plated. The biggest issue today besides finding someone to do them is the fact that galvanizing today is different than it was 50 years ago. My experience has shown that the galvanizing today has much larger flakes than they did years ago due in part to the chemicals as well as the process. I have never been able to find anyone that can replicate the originals.

I either send mine in for zinc plating (only so that I have a good base) or media blast them down to a good surface. Then I use 4 different colors of silver and grey and mottle the backing plates much like you would do painting a wall. The results give a simulated galvanizing effect instead of the real thing but at least they are not bright shinny zinc.

BCreekDave
02-17-2021, 01:35 PM
I have found this:
https://www.mcmaster.com/galvanizing-coatings/

works pretty well, along with the technique that Rick mentioned.

It's all a bit of a simulation until someone takes the time to setup a hot galvanizing process in their garage.

Burd
02-17-2021, 01:36 PM
Mine on my F body sure look to be HDG. As well as the fuel line shield
Who makes the 2 letter paper stickers for the shields?

BCreekDave
02-17-2021, 01:50 PM
Don Lightfoot does them the best.

https://www.angelfire.com/rock/69ss/decals03.html

bergy
02-17-2021, 03:14 PM
We owned a company that had 2 hot dip galvanizing lines. The process is the same today as it has always been. We galvanized iron pipe fittings and iron distribution hardware for the electricity grid. Much of this production has gone off shore due to environmental costs. Also, many formerly hot dipped products have been converted to zinc plating for cost savings (uses less zinc, cosmetically more appealing, but less protective). The grain structure of the hot dip finish is a function of solidification nucleation sites (pre plating treatment, bath temperature, and quench timing). Our company produced 250,000 pipe fittings per day, so the galvanizing lines were automated.

Lynn
02-17-2021, 03:15 PM
Never too old to learn. I don't remember a finish that looked galvanized on my DB backing plates. Granted, it has been almost two decades since I had them apart and plated.

RPOLS3
02-17-2021, 04:15 PM
I think everyone (including me) always assumed that zinc was correct. Through conversations here on this site by people way more knowledgeable than me we continue to learn more about these seemingly meaningless details. I am going through a process on my Chevelle now to "fix" many of the mistakes I made 20 and 30 years ago when I previously cleaned things up and either did not know any better or did not have the resources to do it correctly.

NorCam
02-17-2021, 07:09 PM
Yup...

I cleaned these ones up last fall and noticed they were galvanized. Not any longer. They are now zinc plated.

https://i.ibb.co/FqFZ3Vc/IMG-2352.jpg

https://i.ibb.co/7k4d3VJ/IMG-2355.jpg

Burd
02-17-2021, 08:15 PM
Isnt galvanizing just dipping it in zinc when it’s hot? Looks diff I realize.

R68GTO
02-17-2021, 10:25 PM
I certainly don't disagree that the some of the pics posted above appear to be galvanized with a small pattern spangle. Curiosity got the best of me so I pulled up the photos of mine when I cleaned them up with a low pressure bead blast. I see no galvanizing pattern whatsoever. I don't think I removed it during the blast process as I can still see where the original AD sticker was applied. Maybe the process was different from different suppliers or changed during the model run?

70post
02-18-2021, 01:13 AM
Time (meaning deterioration of the plating) and beadblasting "wipes out" the distinctive flake appearance on these. It all depends on how "weak" the galvanizing was before you worked on the shields. I've dealt with many many pairs of these with the original galvanizing. How much of the distinct flake pattern is left varies quite a bit.

We had a set of gas tank straps hot dip galvanized in Chicago a few years back....didn't turn out very nice and not even close to the small/"tight"/smooth flake pattern you see on the originals.

Will be interesting to see what results anyone gets.

I believe the process was the stamping places bought ROLLED SHEETS of galvanized steel and the parts were stamped out from that....not galvanized AFTER they were stamped out. The soft zinc aided in the stamping process...acted as a sort of "lubricant" and helped prevent some wear and tear to the tooling/dies.

I just looked closely at a pair of NOS Abody gas tank straps I have here....obvious scratching THROUGH the galvanized finish in areas where severe forming took place as well as the cut edges being shiny. Probably evidence of this on the disc shields where the spot welds are (done AFTER the galvanized sheet was stamped attach the center ring to the shield.

Lots of alternator fans exhibit the same properties.


R68GTO....that looks like a very tight flake pattern of galvanizing under the sticker.....it's sure not consistent enough to be regular zinc plating IMO.

Motorhead848
02-18-2021, 04:11 AM
ive noticed things like coil brackets to be galvanized. there some stuff unique to corvettes that were also galvanized....

70post
02-18-2021, 05:42 AM
Olds (which I deal with primarily)....same thing...galvanized coil brackets, etc. Not A LOT of pieces but indeed distinct.

Burd
02-18-2021, 12:42 PM
This is mid way on the sub frame, I cleaned it w/ WD40, you cant bead blast Galv.

RPOLS3
02-26-2021, 01:59 AM
I don't have my hands on these yet to take close up pictures but my guy sent these to me today of the finished product.

firstgenaddict
03-03-2021, 12:51 AM
Looks good and should weather perfectly.

I use the same process on Galavnized parts as Rick (SS427) does... multiple Zinc rich paints including bright Galvanizing Zinc, cold Galvanizing zinc, and weldthrough ZINC and use a piece of ccrumpled up AL foil to give the crystalizing effect..