anybody know where to get a large magnet?

Blown subwoofer or other large speaker = large magnet. Might have to rip the magnet off the speaker's basket... Good Luck with what you're doing

Get one outta a cpu hard-drive...those suckers have some pull

Maybe one small enough to put in through the oil drain hole on the end of a wire???

Depends on how heavy the piece is you are trying to fish out.

Chris

heck a strong enough battery might even allow it to be pulled to the drain plug if you do it while the oil is still in the pan.

The easy part is probably to get it to the drain hole, the hard part is probbaly to get it out through that hole.

Good luck man.

Chris

CPU hard drive? what do you mean? there isn't a magnet anywhere near a hard drive, that would erase it

pwcracer said:

CPU hard drive? what do you mean? there isn't a magnet anywhere near a hard drive, that would erase it

Click to expand...

Friend has a bad a s s mag. on the bottom of his pan that thing has some serious pull to it, he told me he took a old cpu apart and got it from the hard drive.

pwcracer said:

CPU hard drive? what do you mean? there isn't a magnet anywhere near a hard drive, that would erase it

Click to expand...

First off, I think of CPU as being the processor, not the whole computer. Anyway, there are some damn strong neodynium (rare earth) magnets in hard drives. They are used along with a coil to drive the read/write heads over the platters in the drive. The reason that they don't erase all of the data is that they are in 1/8" thick stainless steel enclosures that do a good job of shielding the platters from the magnetic field.

Most non techy users concider the CPU, to be the PC's case. I have worked in IT for 10 years now, and ripped open lots of hard drives, and never found those magnets you speak of.. I even opened one up, poured Pepsi in it, and put it back together.. i reinstalled the drive in my friends PC.. needless to say it did not last too long..

Looks like there is more than one design to control and or move the arm in a hard drive.

The stepper motor design is actually an electric motor that moves from one stop position to another, governed by click stop positions. They cannot stop between stop positions. The motor is small and is located outside the HDA, so it is visible from the outside. The stepper motor design is inferior. It suffers from slow access rate and is very sensitive to temperature. It is also sensitive to physical orientation and can't automatically park the heads in a safe zone. Besides, the actuator operates blindly from the track positions, governed only by the stop positions. Over time, the drive becomes misaligned, requiring occasional re-formats to realign the sector data with the heads.
The servo motor actuator is another type of head actuator motor. Unlike the stepper design, the heads get feedback as to position, assuring proper tracks are read. The guidance system used by the heads is called a servo. Its job is to position the head over the correct cylinder. It does this through the use of grey code. Grey code is a special binary number system in which any two adjacent numbers provide info to the servo as to their position on the drive. Also, the heads are free to move wherever needed...no steps. Basically, when the drive needs to retrieve certain data, the servo motor moves the heads out to the appropriate position on the disk and then waits for the corrects bit of data to spin over to it. The time it takes for all this to happen is called latency, and is a key measure of the speed of the drive.
The voice coil is the latest type of device for controlling the heads and is used on all modern hard disks. The voice coil operates similarly to a speaker. There is a magnet (or magnets) that are surrounded by a spring-loaded coil of wire which is connected to the HGA. As a current is applied to the coil, it interacts with the magnet and swings the assembly. the resulting movement of the heads is from the center of the platters to the outer edges.
When the hard drive is powered down, the springs or actuator coil (depending on the type of actuator) attached to the heads pull the head into the platter. This is called a landing. Every drive is designed to handle thousands of takeoffs and landings, but since the head actually hits the platter, its best to have this happen on a section of platter where there is no data. In a voice coil design, the actuator coil springs the heads into a landing zone and lock position before the drive even stops spinning. The landing zone typically lies on the innermost cylinder or the outermost cylinder. This assures that the heads are not just let go of and left to drag along the platter until the platter stops, a problem common to the stepper motor design. When powered on, the drive automatically unparks itself and the coil is overcome by the magnetic force.

The spindle motor is responsible for spinning the platters. These devices must be precisely controlled and quiet. They are set to spin the platters at a set rate, ranging from 5400 RPM to 10000 RPM. The motor is attached to a feedback loop to make sure it spins at exactly the speed it is supposed to. The speed is not adjustable during operation. Some spindle motors are on the bottom of the drive, below the HDA, while the more modern ones are built into the hub of rotation of the platters, thereby taking up no vertical space and allowing more platters. Attached to the spindle motor is a ground strap which helps rid the drive of the static charges created by the rotating the platters through the air in the drive's interior. In many drives, this can be accessed by removing the logic board. After a while, this strap can become worn and produce noise, like a high-pitched squeal. One can usually lubricate the strap and stop the noise, but this entails some minor disassembling of the drive.

hehe...hackers

:OT:

pwcracer said:

Most non techy users concider the CPU, to be the PC's case. I have worked in IT for 10 years now, and ripped open lots of hard drives, and never found those magnets you speak of..

Click to expand...

pwcracer said:

The voice coil is the latest type of device for controlling the heads and is used on all modern hard disks. The voice coil operates similarly to a speaker. There is a magnet (or magnets) that are surrounded by a spring-loaded coil of wire which is connected to the HGA.

Click to expand...

So, you've never found them, but know they exist?

Hard Drive:


Hard Drive no cover:


Coil cover removed to show coil and magnet:


Magnet holding hard drive in air by screwdriver:


Magnet on stainless mount plate:

Thats the looks like the exact magnent my bud uses....I knew it!

Back to the original topic of discussion

What I'm wondering is .............

Even if you can drag the piece of dipstick to the pan hole (sounds funny don't it?) ...... How you gonna get it turned around so you can get it out of the hole?

I'd sure try it thats for sure, lol.

If that don't work you could always take the tc cover off.

Later
Grady

DAMN, i just thought of it. since the dipstick is pretty flimsy anyway once you can see clamp on simve needle nose vise grips and pull like hell... the dipstick will jsut conform through the plug hole...

Chris

Order part # P8-1136 from http://www.arborsci.com/Products_Pages/Magnetism/MagnetismBuy6.htm#Magnets. You will not believe how strong they are.

I rolled one across my floor and it went right to a nail in the floor joists. I had two of them that I gave to my physics teacher, he wasn't careful enough with them, they snapped together and gave him a nice blood blister. Heck, even if you do get your dipstick out, they are a bunch of fun to play with. If you do order some, get two of them.


Doc