Brake drum wear limit

[halftonstude]

Hello gang,
Got my finals finally pulled apart (pun intended) and working on cleaning. I pulled the drums out and found one had more wear than the other. i guess that's par for the course. My question is, how much wear is acceptable? So, what iIve done for homework is gone to TM's site and they don't have any information. Steiner has a pdf showing the diameter of the drum is 4.504" but no wear limit. Service bulletin (ocr) has no occurrence of the word "drum" anywhere in it, and the service manual only states to inspect the drum for damage and excessive wear, and replace when there is doubt of their serviceability. Well, i have two drums. one is 4.490, so that's only 15 thou less than spec (if Steiner's data is accurate.) The other is 4.345: that's .145" smaller, more than 1/8". But, there's a good deal of metal left. I've read a few other posts about this topic, no cracks or welds. i'll have to turn the smaller one a bit in my lathe to make it flat again which will take off a little more. The question then becomes at what point does the brake band have trouble getting around the drum and is there a diameter someone knows at which point the adjustment no longer works? And this whole thing started with "well, while I have the hood off...." HAHAHAAH! thanks for the help everybody.
c

[Slim140]

If I had a lathe, I’d just make some new ones

[mozer71]

That's impressive work, Shane. One can have a lathe and other machines but it takes time to use them correctly. It is a learning process which you have obviously mastered.

[mozer71]

Sorry. I went off topic there but can't help it sometimes.

[Jim Becker]

Back to the original question, I wouldn't worry about a minimum diameter. Just use it and see if the brakes adjust up OK. You aren't going to be trying to stop from 80 mph!

[outdoors4evr]

Might want to trade sides. Put the high wear one on the lesser used side. In another 50 years they might get back to worn evenly.

[Slim140]

Back to the original question, I wouldn't worry about a minimum diameter. Just use it and see if the brakes adjust up OK. You aren't going to be trying to stop from 80 mph!

I agree with Jim. There should be enough adjustment on the brake rod to compensate for the drum diameter.

The only reason I made some is because the bore was messed up on mine and I like a challenge to make something.

[Slim140]

One can have a lathe and other machines but it takes time to use them correctly.

A man told me once “just because you have a welder it doesn’t mean you can weld” I told him “just because you have a Cat loader doesn’t mean you can do grading correctly”. He said you have a point, he owned his own grading business.

[outdoors4evr]

So..... Practice makes scrap metal? (at least when I do it)

[mozer71]

NO way.

[Jim Becker]

Brings to mind an old saying: "To a man with a hammer, everything looks like a nail." Something similar seems to apply to a lot of farm welders.

[halftonstude]

This is the best part of this forum, when the replies get just slightly off topic and people start talking about all sorts of things. Yes i have a lathe and can make new drums just like the photos. The funny part is when you need a screw, and think the hardware store is 5 miles from here and they may not have it so I'll just make it... I'll probably get a new drum while I'm ordering a bearing (yes found a crack in the outer race... ungh) might as well drop another 30 to get a drum. Golly this whole "well, while the hood is off" is running me about $2500 so far... but I'll have a brandy new cub when I'm done, it'll look great, and hopefully last another 70 years. What a great forum this is, thanks for all the advice, good words, and enjoyable posts!
c

[halftonstude]

the phrase i learned and use all the time is "when the only tool you have is a hammer, everything looks like a nail..." is just as true! this cub had a left final welded all to heck, needed several helicoils to fix things and also ended up getting a "new to me" final from tnt... i don't trust old farmer's welds even if it looks like they used the right rod (this was an application of stainless steel rod, which is ok for cast iron, but i doubt the penetration is enough to make the final secure...) We use the tools that are available to the best of our abilities. At work I often see electricians use things that aren't quite up to code, but i know when the work is pressing you use what you have... doesn't make it right, but makes it work.
c

[mozer71]

Halftonstude. If that means what I think, we are onto a different discussion. I do recognize that we newbies are asking the same questions as several years ago. Our grand mentors (and some are deceased ) knew everything but can't constantly pound it out. That is why we have the files stored here. They are fresher than these tractors and put a person into the plane dedicated to the issue.
I know that real-time replies are important. We find that we are not alone in whatever procedure. That is so cool but we are asking a lot from the Big Guys who have better things to do. Us newbies hash it out awhile and the answer maybe comes later. The reason is; there isn't any real definition at first. It has to be hashed out to arrive to the answer.

[BigBill]

Are your new drums steel or castiron? I believe the originals are castiron. There is a difference in braking and wearing. . Castiron has a nickel content when glazed its surface is rock hard better for braking. The steel I’m not sure about. We tested castiron rotors and steel rotors in the lab for disc brakes for elevators. We had better stopping results with castiron with green gripper lining.

I tested the green gripper lining from McMaster Carr in the weather in my disc braked cub cadet. Works and held up fine. But I’m not sure how it will hold up to bending. It may have to be steamed or warm water to bend it. It’s the highest friction braking material we tested in the lab.