Rotor Disaster
Thread Starter
Drifting
Joined: Sep 2010
Posts: 1,254
Likes: 1
From: Hudson Valley Area New York
Rotor Disaster
I had my rotors zinc plated. I brought them to be powder coated. The guy called me today and said we have a major problem He was suppose to powder coat the centers. He said before he powder coats he has to put a chrome finish on it and baked it at 400 degrees. The high heat and zinc coating made major air bubbles and he cant powder coat them in this condition . He is stripping the down. Will that take off the zinc plating. If I re zinc coat and send them to Customs by Mike will this happen again ? Thanks.
Instructor
Joined: Feb 2011
Posts: 125
Likes: 0
From: Merchantville New jersey
I have had that problem on Non automotive parts that I manufacture. We zinc all our parts and problem isn't the zinc. The part itself is out gassing. The best way to keep that from happening is to pre heat the part. Bake it out at 50 degrees hotter then your normal powder bake temp. Let it cool to the point where the powder can be applied then bake it out at 50 degrees lower then normal for a longer period. This has always worked for my parts.
Team Owner
Joined: Dec 1999
Posts: 174,312
Likes: 1,217
From: Here
Pilot of Beer Force 1
Tampa Regional Coordinator
CI 4-5-6-7-8 Veteran
Organizer St. Jude Fundraiser
I believe in the Beer Fairy
I just had my rotors powdercoated locally and they did no such thing...WTF would they chrome something to powdercoat over it???That makes NO sense whatsoever.
Thread Starter
Drifting
Joined: Sep 2010
Posts: 1,254
Likes: 1
From: Hudson Valley Area New York
I have had that problem on Non automotive parts that I manufacture. We zinc all our parts and problem isn't the zinc. The part itself is out gassing. The best way to keep that from happening is to pre heat the part. Bake it out at 50 degrees hotter then your normal powder bake temp. Let it cool to the point where the powder can be applied then bake it out at 50 degrees lower then normal for a longer period. This has always worked for my parts.
Le Mans Master
Joined: Mar 2002
Posts: 6,359
Likes: 163
From: Concord NC
Le Mans Master
Joined: Mar 2006
Posts: 8,913
Likes: 15
From: El Segundo California
St. Jude Donor '06-'07-'08-'09-'10-'11-12-'13-'14-'15-'16
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Burning Brakes
Joined: Mar 2010
Posts: 914
Likes: 2
From: Newnan Georgia
The "chrome" the powder coater is refering to is most likely a simulated chrome colored powder that is put on as a base prior to a candy or metallic color.
As far as the powder not sticking to the zinc, it depends on how the platers zinced them. Realistically the best way to do it is to strip the zinc from the areas that will be powder coated. Your powder coater should have masked all the areas you want to save the zinc on and then blasted the areas he wanted to coat. Alluminum oxide would be the best choice, 120 grit at around 50 psi should remove all of the zinc on the areas he's going to coat.
D
As far as the powder not sticking to the zinc, it depends on how the platers zinced them. Realistically the best way to do it is to strip the zinc from the areas that will be powder coated. Your powder coater should have masked all the areas you want to save the zinc on and then blasted the areas he wanted to coat. Alluminum oxide would be the best choice, 120 grit at around 50 psi should remove all of the zinc on the areas he's going to coat.
D
Burning Brakes
Joined: Mar 2010
Posts: 914
Likes: 2
From: Newnan Georgia
The more I think about it, the more I wonder why you would want to powder coat instead of the zinc?.. The zinc is a much better corrosion resistant coating and it should be more durable.
Just so you know that I've got a clue as to what I'm talking about, here's some pictures of some rotors that I plated a couple weeks ago. When I say " I plated", I mean I physically plated these. They are Electroless Nickel plated. The only way to get a true even plating in all of the recesses like the drilled areas and fins is to electroless plate them. Some of the cyanide based plating solutions like cadmium have great throwing power, but due to the environmental aspects zinc is a much better choice... I just don't have that option right now though.
I picked these up used really just to see what I could do with them. A lot of prep work, the shinier they are going in, the shinier they are coming out.. I still need to get them resurfaced.
D
Just so you know that I've got a clue as to what I'm talking about, here's some pictures of some rotors that I plated a couple weeks ago. When I say " I plated", I mean I physically plated these. They are Electroless Nickel plated. The only way to get a true even plating in all of the recesses like the drilled areas and fins is to electroless plate them. Some of the cyanide based plating solutions like cadmium have great throwing power, but due to the environmental aspects zinc is a much better choice... I just don't have that option right now though.
I picked these up used really just to see what I could do with them. A lot of prep work, the shinier they are going in, the shinier they are coming out.. I still need to get them resurfaced.
D
Last edited by BigDs_C6; Mar 30, 2011 at 08:25 PM.
Race Director
Joined: Oct 2007
Posts: 11,367
Likes: 211
From: Edgewood Washington
St. Jude Donor '11-'12-'13-'14-'15
I too am baffled by the need to zinc plate the rotors before powder coating.
Are there areas of the wheel that will be zinc and others that are powder or is the whole rotor (except the swept area) going to be powder coated and the zinc is necessary as some kind of base coat?
Either way, good luck.
Are there areas of the wheel that will be zinc and others that are powder or is the whole rotor (except the swept area) going to be powder coated and the zinc is necessary as some kind of base coat?
Either way, good luck.
Race Director
Joined: Oct 2005
Posts: 14,555
Likes: 1,255
From: Saint Albans, WV
The more I think about it, the more I wonder why you would want to powder coat instead of the zinc?.. The zinc is a much better corrosion resistant coating and it should be more durable.
Just so you know that I've got a clue as to what I'm talking about, here's some pictures of some rotors that I plated a couple weeks ago. When I say " I plated", I mean I physically plated these. They are Electroless Nickel plated. The only way to get a true even plating in all of the recesses like the drilled areas and fins is to electroless plate them. Some of the cyanide based plating solutions like cadmium have great throwing power, but due to the environmental aspects zinc is a much better choice... I just don't have that option right now though.
I picked these up used really just to see what I could do with them. A lot of prep work, the shinier they are going in, the shinier they are coming out.. I still need to get them resurfaced.
D
Just so you know that I've got a clue as to what I'm talking about, here's some pictures of some rotors that I plated a couple weeks ago. When I say " I plated", I mean I physically plated these. They are Electroless Nickel plated. The only way to get a true even plating in all of the recesses like the drilled areas and fins is to electroless plate them. Some of the cyanide based plating solutions like cadmium have great throwing power, but due to the environmental aspects zinc is a much better choice... I just don't have that option right now though.
I picked these up used really just to see what I could do with them. A lot of prep work, the shinier they are going in, the shinier they are coming out.. I still need to get them resurfaced.
D
Thread Starter
Drifting
Joined: Sep 2010
Posts: 1,254
Likes: 1
From: Hudson Valley Area New York
I too am baffled by the need to zinc plate the rotors before powder coating.
Are there areas of the wheel that will be zinc and others that are powder or is the whole rotor (except the swept area) going to be powder coated and the zinc is necessary as some kind of base coat?
Either way, good luck.
Are there areas of the wheel that will be zinc and others that are powder or is the whole rotor (except the swept area) going to be powder coated and the zinc is necessary as some kind of base coat?
Either way, good luck.
Thread Starter
Drifting
Joined: Sep 2010
Posts: 1,254
Likes: 1
From: Hudson Valley Area New York
