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Do people still "cut"/surface the rotors? If not, when did this end?

Did rotors get cheap enough where people stopped this practice when replacing pads?
If yes, around what year did this stop? 1980s? 1990s? 2000s?

Not just cheap enough…but TOO THIN to cut. Many manufacturers have reduced the mass of the rotors so much that they can’t be turned…or only able to turn once.

I am sure some people still do it, but few if any car manufacturers recommend it any more. Pads and rotors have changed since rotors have come into service.

The big change is that modern rotors are really designed to be replaced not re-surfaced. There may be situations where resurfacing is a useful procedure, but generally it is best to replace them.

Modern rotors are thinner lighter, giving better performance, ride etc, but less life so they should be replaced. I understand that they may require some surfacing to remove surface issues

If they show any evidence of warping, few if any modern rotors should be machined. Just replace them. The cost difference is minimal.

As for when, well I lived though the change, but it did not happen all at once, In any given year different models from the same company might will have been different.

I might add that while rotors have become lighter it is not a matter of cheaper, but as the weight of the car in general has decreased the best rotor weight has also decreased.

I suspect your real question is not exactly what you asked. It sounds like you may be in the used car market and want to know more about the brakes for specific cars you might be considering. Maybe if you can tell us more about your question, we might be able to answer your real question.

No, I just wanted to know trivia. I am revisiting DIY on cars after a 20 year hiatus. I see there are differences these days. This was an example.

So, around what year did this trend stop?
1980s? 1990s? 2000s?

For me, I would just replace anyway. For me, it’s the labor, not the part. If I am already in there, I just replace everything. Why not.

There is also the time spent going to the place with the brake lathe twice to drop off and pick up, and the fact that they may still tell you that the old ones were too thin to turn. At today’s shop rates it makes more sense not to make that extra trip. And then there is the fact that new aftermarket rotors are fairly cheap. I have paid as little a $12 a side for some made in Brazil. They warped quickly, so I’ve not bought the cheapest ones again.

In the past year I have done brakes of a couple of Grand Marquis whose rear rotors got so thin that the swept part of the rotor separated from the hub. I don’t to THAT many brake jobs, so those surprised me. I don’t think the new rotors seemed all that thin, but they did seem to be light weight. I suspect weight savings is a big part of the thin design . Most all cars have been on a diet for the last 20 years or so.

Be VERY VERY VERY carefull of cheap rotors… I had a good friend who has a 1998 Chevy 1500 Ext Cab, that he purchased used. One day he was driving along and a motor cycle infront of him stopped short due to being cut off by a car in another lane. My friend slamed on his brakes, but the truck made some horrible sounds and did not stop, he ended up hitting the bike, luckly no one was hurt… It turns out the the force of his breaking actually casued the rotor to crack all the way around where it joins the hub (its a one piece unit on this truck) which caused the rotor to seperate from the hubs on both sides of the front brakes. IE he lost both his front brakes on a 4500 LB truck at the same time. They were cheap chinese made rotors and they almost cost a man his life.

It was in the 1980s. As best I can recall, any rotor from the 1970s could be machined, but by the early 1990s, the rotors were too thin to turn. A couple of sets of pads and they were done.

If you’re in a part of the country where rust is not a problem, rotors may be able to be resurfaced once or twice depending on how far out of spec they are. Rotors have become thinner/lighter from the factory to reduce weight and that limits the resurfacing that can be done.
Another factor is cost. My shop has a good working brake lathe. But to buy or replace a brake lathe with all the proper bits and adaptors would cost several thousand dollars. If mine broke tomorrow, would I invest that much money and hope to make it back over the next few years or would I start selling replacement rotors and increase my profit right away? Guess what most shops do?

What is the cost for the typical Honda/Toyota OEM rotor?
For BMW, I think it’s about $100.
For $100, I’'d just replace the rotors every other.
Why not, if you’re already in there.
For me, it’s the DIY/labor not the parts that are the real cost.

I think it was the late 80’s. The cost of them came way down and as it has been said,most can’t be turned. About that time I could buy rotors at my cost for as little as $8.00 and calipers with pads as low as $10.00. It made no sense to turn them. I had a few come back warped but not enough to stop buying them. My supplier always took care me. I also had a local guy who would rebuild most CV Axels for $75.00 and give me a life time warranty.

To me, I see no problems with turning as long as you stay well away from the minimum thickness specs.

My 1998 Camry had brake problems recently that led to some noise and vibration - the rotors were ever so slightly warped… we’re talking miniscule amounts of warpage (which is generally small already) along with some scoring of the rotor. I took the things off, and on the way to the grocery store, dropped them off at NAPA and had them turn them. $25, including tax, and I picked them up on the way back.

After that, the problems were gone. That said, I do expect that the rotor life will be decreased somewhat, even though they took of just a few thousandths at most. OTOH, the car is 14 years old, the rotors were only 3 years old, and I only drive 7-8k per year on that car. Odds are that even with a decreased life, those rotors will last me until the car is almost 20 years old. I do not intend to still have the vehicle by then, nor will I be all that upset if I do have to replace the rotors earlier - a good set will only run $80-100, and I can change them quickly.

At the same time, if the shop was out of the way or I lost too much time waiting for them to turn the rotors, then I would probably have just bought new ones.

The practice has never stopped; it’s just less prevalent and it’s due to economics. Most flat rate manuals will allow something like .8 hours to machine one rotor. If the shop has an 80 dollar an hour flat rate that means 64 dollars to cut ONE rotor. Weigh that against the cost of a new one and keep in mind that .8 is to machine it only; not the labor to R & R it. (meaning remove and replace)

Modern rotors can certainly be machined without a problem as most have about .030 inches of material to work with. Some have far more with .050 or .060 material. Most rotors will clean up with less than .030 being shaved off and a knowledgeable brake lathe operator should be able to tell after the first fast pass on the lathe whether he thinks it will clean up or not.

I think that a lot of times the blame may be placed on a rotor for being too thin when in fact it may be due to the person cutting the rotor. (Not properly centering the rotor on the cones of the lathe, shaving too much off, or not performing a final slow cut. Regarding the latter, the person running the lathe wants to be rid of it instead of waiting 10 minutes for that final slow cut so they leave it on fast.
In some cases the rotor surfacing may be fine and any ensuing vibration caused by failure to service the caliper slides. Guess what gets the blame; the rotors.

Sounds like like many things, …it’s just cheaper to replace than service.
Gotta love deflation !

I’ve seen a few local gas stations machine rotors on the cheap (as in 10 bucks each) but their methodogy is not desireable in my opinion.
The set the lathe on FAST and prune off as much metal as possible in a pass; all in the intereset of getting it done as quickly as possible.

Any cutting should take multiple passes with a little a time being removed and the final pass should be on the SLOW setting with a chatterband in place. This provides a nice smooth surface that should be problem free although granted, it does take considerably longer to cut them this way.

I get a lot of mileage out of a set of pads, usually around 40K, manual transmission, econobox, and light foot, so I’ve never replaced a brake rotor yet in close to 200K. I measure the rotor thickness of course each pad change to veryify it is within spec. When I do change the pads, I take the opportunity to take some 120 grit alum-oxide sandpaper and go over the rotor in a circular motion (by hand) for a few minutes, then I finish it off with a radial direction (center to rim) straight line motion. Helps remove any glazing of the rotor and helps the new pads seat. At least that’s my theory. I finish it off by hosing off any sand-paper residue with a garden hose. Not sure if it works with modern cars (mine is 20 years old) but that procedure has worked fine for me as long as the rotor thickness is within spec and there’s no grabbing or pulsing indicating a warped rotor.

I’ve replaced the front rotors once and never replaced or turned the rear drums on my '88 Escort in 518,700 miles. The only reason I replaced the rotors then was because they were warped. If people would keep an eye on their brake pad/shoes and replace them before they get metal to metal contact 90% of the time the rotors would be fine. There was no question for me whether to get new rotors or have the old ones turned since the cost of new rotors was only about $10-$15 each. At the time I think NAPA charged about $10 each for turning rotors.

My community has a shop that only does brakes and has a good reputation. Back in th early 1990s, I had the shop put new pads on my 1978 Oldsmobile and the shop said that the rotors were fine. I had driven over 50,000 miles on the pads. I said something about hoping that I would be as fortunate on my 1988 Ford Taurus. The proprietor suggested that we take a look at the pads on the Taurus. He said that the Taurus rotors were known to be thin and couldn’t be turned. I had him replace the pads–I had gone about 40,000 miles. Less than a month after I had the pads replaced on the Taurus, I had a recall notice from Ford about the rotors. Apparently they were not of the proper thickness. The Ford dealer installed new rotors at no charge.

I once bought a set of Nissan pads for my daughters car. The original front pads had lasted 80,000 miles and I think such performance should be rewarded with loyalty.
The surface of the new pads had a sandpaper -like grit built in to deglaze the rotor.
I liked that idea so much that if I am replacing the pads and not the rotors I put a piece of 120 grit sandpaper on the inside of the pads with the other 3 wheels on the ground and blocked and hold my foot lightly on the brake with the engine turning the rotor.

My wife is still on original front rotors on our 2005 Legacy GT with larger brakes. They have been machined twice but labor rate is a relatively low $60/hr.