When installing NOS drums......

[watchfatha1]

Hello all.
By dint of circumstance I happened upon a set of 4 NOS brake drums for my 66 Imperial. (Yes, they were VERY expensive-but how often does an opportunity like that come along?).The friction surfaces were covered in a blue protective coating, which kept them from rusting. The surfaces are shiny and nice now that the blue stuff has been removed. Question: would you rough up the surface or just keep it clean and install it? (I am tending toward the latter, reasoning that after drums are "cut" and shiny, nobody roughs them up).

Let the opinions fly.....

Norm

[ImperialAtom]

From my understanding, the roughing up is done to help the new pad rub off all of the remaining old pad particles from the drum/disc. If you have a new drum or you machined your drum smooth again, I don't think there's any reason to rough up the pad.

[gary h]

I would not rough them up, Just install Clean drums.

[watchfatha1]

Exactly what I did, thanks to both of you. Not only do they stop quickly and straight, there is no longer any minor roughness in the wheel caused by original drums that were balanced when new but were near the end of their service life so the weights they carried were not as well matched to the balance requirement as before. I HATE even the slightest vibration. Now, its perfect.

[gary h]

Glad to hear. Did you get them from Craig @ mobileparts ?

[watchfatha1]

Nope. They were advertised on Craigslist for quite a while. I finally went to see them a couple of days ago and measured them-under 11 inches (max allowable 11.090), LOTS OF MEAT! And I can make more than one high speed stop with no fade.

[gary h]

Ok, Since we are on subject, do you know the purpose of the Spring that mounts to the outside of the drum ? Thanks in advance.

[watchfatha1]

To quiet noises (squeaks-sqeuals) as I understand it. I did not transfer them-and so far I don't hear anything different, but the difference in rolling smoothness is noticeable. It had always felt like a slight out-of-balance condition that I tried several times to address by re-balancing the tires, to no avail. It wasn't the tires, it was the drums, thus confirming what I had long suspected.