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Old 04-08-2013, 08:04 PM   #1
Duffy1
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Default Brake drums ; cast iron vs ductil cast iron .

Just received Bratton`s 2013 catalogue . In the brake section they offer U.S. made ductile cast iron brake drums which they say are 2 times as strong (?) as cast iron brake drums . Just my luck . I just completed a brake job on my 31 s/w installing U.S. made cast iron brake drums from Snyders . So the question is . How much ( 2x ?) better does ductile cast iron drums stop than cast iron drums. All feed back appreciated .
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Old 04-08-2013, 08:43 PM   #2
MikeK
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Default Re: Brake drums ; cast iron vs ductil cast iron .

I believe both the Brattons and Snyders US made drums are the same ductile (nodular graphite) cast iron. The imported drums are standard gray (flake graphite) cast iron. Strength is not the real issue. Resistance to cracking is.

In the US the DOT does not permit gray iron drums on trucks, only ductile. An extremely hot gray (flake graphite) cast iron drum splashed by driving through a puddle can fracture causing a catastrophic wheel lock up. With ductile iron, the drum only warps severely, ruining it, not you.

A secondary issue is specific to model A's with swaged wheel studs. I personally know of several of the cheaper import non-ductile iron drums that developed hairline cracks radiating from the studs where the swage imparted tensile stress.
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Old 04-08-2013, 09:25 PM   #3
Duffy1
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Default Re: Brake drums ; cast iron vs ductil cast iron .

MikeK ;

Thanks for the response . As usual, very informative .
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Old 05-10-2013, 06:40 PM   #4
Mel Gross
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Default Re: Brake drums ; cast iron vs ductil cast iron .


I am one of the suppliers of cast iron brake drums for Ford Model A’s and would like the opportunity to explain my view of this.

I have been selling these brake drums for over 5 years now and have never had a customer complain about them cracking.

Now I do have to omit that I have cracked a couple of them while pressing the hubs & drums together and I have pressed hundreds of them. Some customer have cracked them too, but omitted to improper support on their press. I press these on a 40 ton press using only 22-25 tons of pressure. When I cracked these, it was because I did not position the press table support directly on the head of the stud and the stud slipped off of the tooling.

I sell a lot of these brake drums to garages, stores, and individuals. I have a very high reputation in the Model A and auto parts industry. I would not jeopardize my reputation on an inferior product.

I have total control on the production and quality of these drums. My supplier is my son. The company he works for imports and sells millions of brake drums and rotors a year. They sells them to major aftermarket distributors and retailers. If there was a quality issue, then I would stop selling them and fix the problem or simply stop selling them.

I decided to sell these drums as a service to all of my fellow Model A friends. You have a choice. You can spend a lot of money for them from whomever, or buy them from me.

I will also put in writing right now / right here that if someone has a crack drum of mine and did not crack it during the pressing or swedging process, that I will replace the drum free of charge. You pay the shipping to me and I will send a replacement drum to you and pay the shipping to you. The only thing that I ask is that you be fair and not take advantage of me. I know how long my customers have had them and there need to be a limitation to the amount of time.
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