Where Do Hard Drive Heads Come From?

[KITH]

I don't think it matters whether vertically or horizontally mounted. There are designed for both.

 

[michaelahess]

I've installed and used thousands of hard drives over the last 20 years. All manufacturers have their off years/models. Right now they are all very good in my opinion. I have no problem using Seagate or WD, and I like Samsung as well. I really think the 5 year warranty Seagate has, says a lot about their product.

I have returned well over 100 bad drives over the years and WD and Seagate have always been the best, online rma, print ship labe, get back in a week, never longer for any of mine. Fujitsu and Samsung seem to take longer but just as easy.

The ONLY drives I've had a near 100% success rate with are enterprise class SCSI drives from Fujitsu, Seagate, and Hitachi, I'd venture to say over 500 drives in the same time frame with only 2 or 3 going bad. And I've had these drives last over 10 years under continuous operation in many servers.

Those of you putting out your opinions based on a couple to a couple dozen drives, just don't have the quantity to qualify your statements.

I know many people that have good luck with Chevy's for many years, and one or two who only have problem after problem with the exact same vehicles. Until you get into large quantity's to compare, you can't get a good overall impression of quality/reliability.

The only company I would list as bad and won't buy is Maxtor, mostly from their terrible drives back in the late 90's, I'm sure they've improved but I still have a mind block about buying them

 

[ChuckAtkins]

"In a Seagate disk, the only components that are outsourced (supplied by sub-contractors) are the control ICs."

Not true. I used to work for Hutchinson Technology, http://www.htch.com/diskdrives.asp . They produce the high end suspension systems that the heads mount to (part of the actuator assembly in the picture). While we only produced the parts for the high end drives (enterprise and noteboook units), they outsourced the suspensions for thier desktop drives as well (to our competitors). Every few years, Seagate tries to do everything in house. That usually only lasts a month or so when they realize that external firms that are highly specialized in certain components can produce much higher quality and for much cheaper than they can in house.

I wouldn't be suprised if many of the other components are outsourced as well, reguardless of what seagate tells you.

 

[irl-g-rad]

My first hdd was 500MB Seagate smuggled from Austria - that piece of equipment would work to this day if I wouldn't buy new computer I'm sure. I used it for some 4 years and with WD I had only bad experiences mostly because of stupid dealers' handling... (they were sending HDDs in cardboard box!). I've got fast WD HDD as a C: drive now and Seagate HDD as storage drive, so it's a happy marriage ;-)
I never experienced any problems with Seagate, IBM, SAMSUNG, WD drives while using them (even second hand old ones).

 

[Guest]

Glad I got a WD!

 

[afrobacon]

i have had extremely good luck with hdds; i've bought probably close to 100 or so with only 2 or 3 going bad (that i know of.)

the only one i really praise is my 30gb maxtor; i dropped that thing down a flight of wooden stairs and it still ran like a champ; even to this day, after being tossed around like a light up bouncy ball for the last few years (not literally) it still works.

as far as brand loyalty goes, my vote goes to whoever has the cheaper prices at the time...

 

[cape consultant]

I totally agree with whoever said that how can it possible be more expensive to manufacture SSD's seeing all this extremely high tech that goes into hard drives? I have always thought this. MAn, this is some kind of complicated process. I can still hardly believe that any given drive EVER works! POWER TO THE HARD DRIVE!

 

[zodiacfml]

the principle of mass producing items makes hard disks cheaper not like SSD's which is really new and few will only buy.
i had bad luck with all WD drives i bought, 1 failed after one year, two failed under warranty. one replaced drive is slower than normal.
anyways, i had luck with all seagate drives, they usually fail in 5 to 6 years and seems heat is little factor to their life span.

the feature should have also mentioned that harddisks uses the most powerful permament magnet in the world. i opened two disks and took their magnets then install it to my oil filter in my car so that it will attract small metallic particles in the oil.
don't know if it's effective at all since the oilfilter could filter larger particles.

 

[Guest]

Investment of 150 M € is big. No wonder HD Producers are like Milk farmers. Big investment is like Sharps new 10G ( the HD are at least at 20G ) Factory is more than 4 Milliard $ or 4 Billion $ if you´re american. No wonder the HD market is in such a dissaray. And remeber Seagate is by far the biggest guy in the business.

Laughing from Germany ...

 

[Guest]

Ahh I assumed it was the platter that spun interesting

 

[Oevre Clocker]

I look under my hood of my hard diks and I saw a massive head

 

[FredrikM]

There is something not quite right here. I think you mix two different scales. On one hand you scale the read head to an airplane, on the other hand you scale the surface to the size of the earth. In that situation you can't get a consistent scaling of the distance between the head and the surface.
Lets do som maths: The land surface of the Earth is 510 million km². The surface of an ordinary 3.5 inch disk is about 60 cm². With five platters we get 300 cm², or 3*10^-6 km². So we have a scaling factor of 5*10^13. This means that if the Boeing flies one cm above ground, the read head would fly 2*10^-16 meter above the surface. That is about a millionth of an atom's diameter, which of course is un realistic. A normal flight height is about 10^-8 meter according to this site
http://www.storagereview.com/guide2000/ref/hdd/op/heads/opHeight.html

 

[neiroatopelcc]

[citation][nom]Anonymous[/nom]To neiroatopelccWhat is this you want to see a paper trail?Why would any one want to make up such a story?As for WD right to replace a drive with a repaired one, try reading my post again. I did not have a problem with that. My problem is it failed again and they would not make good on it. I all so did not like there attitude when I called them about it.If you’re so in love with WD then my advice to you and only you is to keep on buying from them. That is you right and I respect that I don’t how ever respect your suggestion that I made such a think up! Why would some one want to do such a thing? In your post you did not even take time to invent some made up motive for me to do so! So keep on making love to WD. People like you will never believe anything until they catch there disease. So for you keep on buy WD drives and I think you will learn the hard way. For every one else this is my experience for your benefit it up to you to decide what you want to do. Paper trail, go check out the men’s room for your paper trail!I would like to know if any one else has had a bad experience with WD as in all fairness this could have been an isolated incident but even so I’m not happy with them.[/citation]

Just had another seagate drive break down over the weekend. In my parents system. It almost lasted a year though, so that's more than average for those seagate drives I've seen fail.... rubbish brand.

 

[FredrikM]

[citation][nom]FredrikM[/nom]The land surface of the Earth is 510 million km².[/citation]
A typo: I meant to write 150 million km².

 

[Guest]

Just had another seagate drive break down over the weekend. In my parents system. It almost lasted a year though, so that's more than average for those seagate drives I've seen fail.... rubbish brand.


Again to: neiroatopelcc

What a coincidence. How so awfully convenient.
Sounds like your well over due for a trip to rest room.

 

[neiroatopelcc]

[citation][nom]tvc34567[/nom]Just had another seagate drive break down over the weekend. In my parents system. It almost lasted a year though, so that's more than average for those seagate drives I've seen fail.... rubbish brand.Again to: neiroatopelccWhat a coincidence. How so awfully convenient.Sounds like your well over due for a trip to rest room.[/citation]

convenient ? in what possible way does working, for free, in my sparetime become convenient ?

Let's just face it. Seagate drives are prone to failure. End of story. Really.

 

[shushikiary]

Pei-chen, to answer your question, it doesnt really matter. However I will say that mounting a drive on it's side may reduce it's performance, but not by much. Seeks away from gravity will be harder and might take longer, however servo firmware does a VERY good job of making sure that the current profile for the head stack motor is finely tuned to meet a seek profile. Different drives have different seek profiles based on how noisy you want them to be, how fast, etc. And by reading the servo wedge patterns on the disc they can accurately feedback how fast they are seeking and update the current, so you may see a very small decrease in performance mounting it sideways, but not by much. The other only thing I could think of that might be a problem is the fact that the fluid bearings for the disc stack might not be too happy being mounted side ways.

I will say that we do all our testing of drives in the labs here with the drives mounted horizontally, if that makes you feel any better.

 

[neiroatopelcc]

Both fujitsu-siemens and hp have models where they mount the drives sideways, or even topdown, and they still offer the same warranty, so I don't think there's much risk involved in doing so. Dunno about performance differences though, but my raid5 at home runs with drives mounted sideways and reaches 250mb/sec top

 

[nanoprobs]

Takes 2 hours to establish a high vacuum? What kind of pump are they using? Why not use a V8 or V12 Engine to establish a Vacuum? This way it will be much faster. Might be more expnsive because of petrol powering the engine, but should be faster.

 

[Guest]

The jumbo jet analogy is incorrect, a colleague of mine formulated a few rough calculations:

Given head dimensions (we only get two, we’ll assume it’s square for simplicity) 90x90x10 (nm)
And height of 40 atoms above disc (an atom is about 1 Å = 0.1nm) = 4 nm.

And 747 dimensions (from Wikipedia) 70.6 x 59.6 x 19.3 m

And say the disc has a radius about 5cm or so and is spinning at 15,000 RPM

15,000 RPM = 250 Hz
Circumference = 0.05m x 2 ~ 0.314m
So the head will be moving at a maximum of 0.314 x 250 m s-1 = 78.5m s-1
So the head covers 78.5 / 9x10-8 lengths every second = 8.72x108 s-1
If a 747 covered this many lengths per second, it would be doing 8.72x108 x 70.6 m s-1 = 6.16x1010 m s-1
Which is 205 times the speed of light, or Mach 178,000,000 (using a speed of sound of 346.1 m s-1 at 25o C and standard pressure)

The height to altitude ratio is 4 / 10, so applying this to the 747 we get 7.7m altitude.

 

[neiroatopelcc]

[citation][nom]MuzzaTheMathsWhiz[/nom]The jumbo jet analogy is incorrect, a colleague of mine formulated a few rough calculations:Given head dimensions (we only get two, we’ll assume it’s square for simplicity) 90x90x10 (nm)And height of 40 atoms above disc (an atom is about 1 Å = 0.1nm) = 4 nm.And 747 dimensions (from Wikipedia) 70.6 x 59.6 x 19.3 mAnd say the disc has a radius about 5cm or so and is spinning at 15,000 RPM15,000 RPM = 250 HzCircumference = 0.05m x 2 ~ 0.314mSo the head will be moving at a maximum of 0.314 x 250 m s-1 = 78.5m s-1So the head covers 78.5 / 9x10-8 lengths every second = 8.72x108 s-1If a 747 covered this many lengths per second, it would be doing 8.72x108 x 70.6 m s-1 = 6.16x1010 m s-1Which is 205 times the speed of light, or Mach 178,000,000 (using a speed of sound of 346.1 m s-1 at 25o C and standard pressure)The height to altitude ratio is 4 / 10, so applying this to the 747 we get 7.7m altitude.[/citation]
Been a few years since school, but I kinda thought I was good at math in school - yet I don't understand anything you just wrote - except the final statement of the plane flying at 7.7m hight ...


ps. you must be horribly bored! was your car or something

 

[daflory]

Really nice article. Thanks! It's easy to forget how miraculous these little drives are.