Fortunately, those are already disassembled (at least one side). I've dealt with more difficult, but these were replaced with too-cheap parts in the near past, which might be why they came apart easier. I got more expensive ball joints this time around.
I'll have to take a look in there when I have it jacked up; maybe I can get those done at the same time.
Most (if not all) cars post 1968 have locking steering wheels when the key is taken out.
I do lots of swap meets, sales, etc. I get almost everything used. Old tools (especially hand tools) are usually better made than new stuff, in my opinion -- not to mention far more affordable.
Not sure what country Xeno lives in, but in the U.S. gravel roads are still quite common, even short stretches in urban areas, especially on roads not maintained by the city or county. Sometimes the entity that controls the unpaved road is able to get enough money to pave it, but often there are reasons to not pave it.
In the U.S., a lot of unpaved roads are in county, state, and national parks, and are necessary to use to get to the destination.
In some cases an unpaved road is a much shorter route than the paved alternative, but sometimes the gravel roads are gated and only property owners along the road are allowed access, even when it's not a private road. We have one such road near me
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, this is maybe ten minutes away from the heart of Silicon Valley.
Unpaved roads can vary greatly in quality. In most cases, no off-road vehicle with high clearance is necessary, in some cases it's an absolute requirement. For example, in Death Valley National Park, in good weather most vehicles would have no problem on Titus Canyon Road unless they have abnormally low clearance. But to drive Lippincot Mine Road pretty much requires 4WD and high clearance
I always brake this way either way. It wigs me out when I ride with people who slow down quickly. Perhaps because I'm used to old beaters with less reliable braking systems, but I always take it easy and pulse the brakes when slowing down.
My 2012 BMW 135i MSport Edition weights 4,255lbs, so stopping it from
60mph must dissipate 694,273 Joules.
We'll assume that all the energy of the stop remains in the rotors themselves, and that BMW has done it's job properly and that therefore the front and rear brake rotors are proportional in mass to the energy each must dissipate.
So we can take the total mass of the rotors, the heat capacity of steel and calculate the change in temperature.
The mass of those rotors is 34.47kg
The specific heat of steel is about 420 joules per kilogram per degree
420J/kg*c
So with 34.47kg, we get 14,477.4 J per degree C temperature change, and dividing the 694,273 joules we've got, we get a temperature change of...
...just about 48 degree.
If it's a warm summer day, you're not going to want to touch the rotors, as they will now be above the boiling point of water (about 120°C)...
(Provided you ignore the energy lost to the airflow and also dissipated by the mass of the pads and calipers themselves, as well was the energy conducted into the hub of each wheel)...
...but it's hardly going to be enough to deposit brake pad material onto the disk.
This is why brake bedding procedures call for MULTIPLE retardations from highway speed in order to get the disks hot enough to deposit an even layer of pad material onto the surface.
I know this, because in my amateur racing "career", I'm also a senior racing instructor, and because our students are driving road cars for sessions where the brakes actually WILL get to the temperatures that can cause that kind of deposition, we always tell them not to apply the parking braking when returning to the paddock after a session.
Shocker:
One again, Arlen hasn't the slightest clue what he's talking about.
Good. Almost nobody knows that the key is to brake harder earlier, rather than braking harder later, and, most importantly, NOT leaving your foot on the pedal at the stop.
I've never met a person in my life who was adamant that his rotors warped who had ever measured the warp they're so very certain happened, that didn't.
It's one more case of how shockingly stupid most people are.
Assuming a similar time to stop the vehicle, it makes no difference whether you stop quickly or slowly; the range of "quick" to "slow" isn't sufficiently different.
If you start from the same speed, and brake to the same place...
I remember many years ago watching a "for schools and colleges" TV science programme at school about "energy". It talked about converting kinetic energy into other forms. As an example, they rigged up a camera on a car, pointing at the front brake disc. They they took it on a racing track (they emphasised that this was off-road!), and repeatedly accelerated to 70 and then braked hard to a stop. After a few cycles of this, the discs were glowing cherry red. I was quite surprised that discs would get *that* hot, and that brake pads would withstand contact with red-hot metal.
Regarding brake rotor warp (as in "potato chip"), that (almost) never happens on rotors that didn't come out of the factory already warped.
Regarding temperatures, the _melting_ point is (almost) impossible to reach in braking operations given the type of vehicles we're all talking about.
Regarding pad deposition, it's hard to believe, (even for me), but it takes only a small amount (almost impossible to measure directly) of "bump" of collected pad chemical "footprint" to build up to the point it's felt while braking (usually at highway speeds).
Just as I ask all iKooks for a _single_ fact that backs up their entire belief system (and they almost never can answer that simple question), I ask anyone who claims their rotors warped what the measurements were.
Don't even get me started on the "cellphones cause accidents" intuition, by the way, as monkeys intuit all sorts of stuff that doesn't show up in independent statistics outside {police,insurance,law} politics.
If someone wants to claim "cellphones cause accidents", I only ask them for one fact, which they never can produce... and which is the only fact that matters.
Marketing and politics takes advantage of people's emotions & intuition.
I realize you're responding to another point from another person...
My point is... In terms of what people call "rotor warp", the primary point I'm trying to make is that holding the pad against the hot rotor at the end of a stop is the one thing you want to avoid (any way that you can avoid it).
It doesn't matter as much _how_ you stop as not holding the pad firmly against a hot rotor when you're done stopping.
Although we could discuss the total amount of heat being dissipated in a short hard fast stop versus a long slow rolling stop - but that's another thing altogether to my point about "rotor warp" (as people call it).
What's to discuss except for the fact that if the stops are both from the same initial speed, you'll be dissipating precisely the same amount of energy as heat?
When I was doing a lot of brake repairs, and operating a brake lathe, I came across many warped rotors. One is required, after all, to check discs and drums for wear, distortion, runout and the like. In my experience, there were two possible factors involved in warped discs - overheating of rotors and incorrect sequence tightening of wheel nuts. Or simply overtightening. And, no, they didn't come out of the factory already warped. The worst for warping through overtightening were the integral hub and disc rotor. The separate rotor tended to be more prone to warping through overheating. Note too, a warped disc will evince different symptoms to a disc suffering pad deposition. The first car I owned that suffered from disc warping was a MkII 240 Ford Cortina but I drove that thing like a rally car back in the days.
I managed to reach it on one car I owned back in the early days of disc brakes. Admittedly, the rotor was sub par on the thickness hence a reduced heat capacity. It sure melted at the periphery though and was showing signs of heat stress all over - it was black and blue. ;-)
Who remembers actual numbers from a couple of decades or more back? I used to measure runout, thickness variation, taper, etc, compare to specs, then machine. If they wouldn't clean up and still remain within specs, they would be replaced, and that could be determined from the measurements.
This was my preferred brake lathe;
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Though not that current model.
You need to be very careful these days as some marques feature disc rotors that cannot be machined. The rotor is considered a disposable item just as much as the disc pads are. It's the only way by which the manufacturers can get the friction coefficients up to acceptable levels.
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