From: Chris Whelan on
On Sun, 06 Jun 2010 17:49:57 +0100, Mrcheerful wrote:

> Peter Parry wrote:
>> On Sun, 6 Jun 2010 15:12:37 +0000 (UTC), Jeff The Drunk <i-am(a)the.bar>
>> wrote:
>>
>>
>>> Really? What kind of hard drive has a big flat magnet inside?
>>
>> Most modern ones that use voice coil positioning for the heads.
>>
>>> That defies
>>> all logic on the principals of how a hard drive works.
>>
>> Cunning design (the N and S poles share the same face) and a bit of
>> shielding keep the magnetic field contained and the platters safe.
>
> Any idea what that shield is made of? it looks like aluminium, but
> isn't.

http://en.wikipedia.org/wiki/Mu_metal

Chris

--
Remove prejudice to reply.
From: Ian Dalziel on
On Sun, 6 Jun 2010 17:22:01 +0100, "Mrcheerful" <nbkm57(a)hotmail.co.uk>
wrote:

>Monty wrote:
>> Ralph Mowery wrote:
>>> "john hamilton" <bluestarx(a)mail.invalid> wrote in message
>>> news:hugc8b$uec$1(a)news.eternal-september.org...
>>>> Have tried using the strongest cuboard magnet I can find (In north
>>>> London u.k.), but if the wind picks up surprisingly it will just
>>>> not hold. Also
>>>
>>> The magnet out of a hard drive is flat and very strong.
>>>
>>>
>>
>> Pmsl!
>
>why?
>

Prostate trouble?

--

Ian D
From: Dave Liquorice on
On Sun, 6 Jun 2010 15:44:16 +0100, john hamilton wrote:

> Since the door just swings open I have to keep getting the keys out of
> my pocket to open the door.
>
> I would like the door to stay shut on its own accord, yet just open with
> a push without having to use the keys.

Rehang it so that it's natural rest state is closed not open. I
*think* with a normal opening inwards door that means the top hinge
slightly further into the jamb than the bottom hinge.

--
Cheers
Dave.



From: PeterC on
On Sun, 6 Jun 2010 17:49:57 +0100, Mrcheerful wrote:

> Peter Parry wrote:
>> On Sun, 6 Jun 2010 15:12:37 +0000 (UTC), Jeff The Drunk <i-am(a)the.bar>
>> wrote:
>>
>>>
>>> Really? What kind of hard drive has a big flat magnet inside?
>>
>> Most modern ones that use voice coil positioning for the heads.
>>
>>> That defies
>>> all logic on the principals of how a hard drive works.
>>
>> Cunning design (the N and S poles share the same face) and a bit of
>> shielding keep the magnetic field contained and the platters safe.
>
> Any idea what that shield is made of? it looks like aluminium, but isn't.

Would it be mu-metal - an alloy of nickel IIRC?
--
Peter.
2x4 - thick plank; 4x4 - two of 'em.
From: OG on

"john hamilton" <bluestarx(a)mail.invalid> wrote in message
news:hugc8b$uec$1(a)news.eternal-september.org...
> When working on my car, I bring it right up close to the house and lay my
> tools out on the floor behind the front door. Since you never know when
> it will rain, it works out very handy since then all I have to do is close
> the door; and don't have to be picking up all the tools.
>
> Now if its not warm the family doesn't like the cold air coming into the
> house and they want the front door shut, which is fair enough. Since the
> door just swings open I have to keep getting the keys out of my pocket to
> open the door.
>
> I would like the door to stay shut on its own accord, yet just open with a
> push without having to use the keys. There is no room on the door jamb to
> screw one of those helical spring self closers. And anyway in general use
> we dont want the door to close by itself. Which also rules out one of
> those hydraulic self closers which could fit on at the top of the door.
>
> Have tried using the strongest cuboard magnet I can find (In north London
> u.k.), but if the wind picks up surprisingly it will just not hold. Also
> tried cutting a thin wedge of cork glued to an upright jamb which makes
> the door a tight fit when closed. However the door shrinks in the summer
> and expands in the winter so that only works for about half the year.
>
> Grateful for any suggestions, especially something similar to the cork
> arrangement which works just fine prividing the weather suits it.
> Thanks.

Screw a hook in the frame above the door about 1/3 way out from the hinge.
Get a beanbag (or equivalent) that weighs about a pound and tie it to a
piece of string about 1.5 metres long and put a loop in the other end.

When you're working outside, loop the string over the hook. The weight of
the beanbag should keep the door closed, and it can be removed when you're
not working on the car.