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Door Hinge Bobbin hole size question, and an Update

PostPosted: Mon Sep 26, 2005 8:32 pm
by "Ian Phillips"
-----Original Message-----
From: ***@***.***lto:***@***.*** Behalf
Of david_cusworth
Sent: Monday, September 26, 2005 6:13 PM
To: ***@***.***
Subject: [LotusElan.net] Re: Door Hinge Bobbin hole size question

Through hole.......what through hole? What is it for? If it's drainage the
water will go into the car.

David

--- In ***@***.***, "Ian Phillips" <[email protected]> wrote:
Does anyone know the diameter of the central (through) hole in the
Mazak

hinge bobbin (the ones bonded in to the bodywork)

I have a cunning plan to refurbish the door hinges on my S4 and
want to make

a tool that spigots in the bottom of the hemispherical recess. I
know the

hemispherical recess is 5/8" diameter but if anyone has easy
access to a

door aperture, or has a spare bobbin they can get to without
taking a door

off I would be grateful if they could take a couple of
measurements.


Apart from the hole diameter I would also like to know the wall
thickness of

the die-casting, and the thickness of the top flange.

TIA

Ian Phillips

David

I am not sure what the through hole was put there for originally. My
suspicion is that it was used to locate the bobbin in the mould when the
body was being laid up.

Anyway, the through hole is about 3/16" diameter. For the purposes of my
door hinge improvement scheme I drilled out the hole to 8mm. Interestingly I
found that some of the swarf that came out was magnetic, so there seems to
have been some steel plate/bracket or whatever very close to, or fastened
to, the bobbin.

I did not remove the interior trim but would be interested to know if the
bottom door hinge bobbins are fastened to something other than just
glassfibre.

When I removed the door last weekend I found that the bottom hinge bobbin
had worn severely oval to the extent that the Mazak was completely worn away
at one part of the hemispherical recess.

I will post some pictures in the next few days showing the Bronze 'shell' I
made to reline the body recess, the stainless steel hemispherical (female)
adjusting screw, and the stainless steel ball bearing.

The drivers door now closes in a much more satisfying manner, not like a VW
door does though!


Ian Phillips

Door Hinge Bobbin hole size question, and an Update

PostPosted: Tue Sep 27, 2005 7:55 am
by cusword
As you know my interior panels are not in the car at the moment, so
I just had a look. The two bottom bobbins just sit in the sill.
From the underside there is no additional steel support. It just
looks like any other bobbin. On invesigation is does seem there was

a through hole that was filled, presumably to keep the water out.
The hole is probably to locate the bobbin, on a pin, on the jig.

Bye.............

David

--- In ***@***.***, "Ian Phillips" <[email protected]> wrote:


-----Original Message-----
From: ***@***.***lto:***@***.***
On Behalf

Of david_cusworth
Sent: Monday, September 26, 2005 6:13 PM
To: ***@***.***
Subject: [LotusElan.net] Re: Door Hinge Bobbin hole size question

Through hole.......what through hole? What is it for? If it's
drainage the

water will go into the car.

David

--- In ***@***.***, "Ian Phillips" <[email protected]> wrote:
> Does anyone know the diameter of the central (through) hole in
the

Mazak
> hinge bobbin (the ones bonded in to the bodywork)
>
> I have a cunning plan to refurbish the door hinges on my S4 and
want to make
> a tool that spigots in the bottom of the hemispherical recess. I
know the
> hemispherical recess is 5/8" diameter but if anyone has easy
access to a
> door aperture, or has a spare bobbin they can get to without
taking a door
> off I would be grateful if they could take a couple of
measurements.
>
> Apart from the hole diameter I would also like to know the wall
thickness of
> the die-casting, and the thickness of the top flange.
>
> TIA
>
> Ian Phillips

David

I am not sure what the through hole was put there for originally.
My

suspicion is that it was used to locate the bobbin in the mould
when the

body was being laid up.

Anyway, the through hole is about 3/16" diameter. For the purposes
of my

door hinge improvement scheme I drilled out the hole to 8mm.
Interestingly I

found that some of the swarf that came out was magnetic, so there
seems to

have been some steel plate/bracket or whatever very close to, or
fastened

to, the bobbin.

I did not remove the interior trim but would be interested to know
if the

bottom door hinge bobbins are fastened to something other than just
glassfibre.

When I removed the door last weekend I found that the bottom hinge
bobbin

had worn severely oval to the extent that the Mazak was completely
worn away

at one part of the hemispherical recess.

I will post some pictures in the next few days showing the
Bronze 'shell' I

made to reline the body recess, the stainless steel hemispherical
(female)

adjusting screw, and the stainless steel ball bearing.

The drivers door now closes in a much more satisfying manner, not
like a VW

door does though!


Ian Phillips

Where did Lotus get the door hinge bits from?

PostPosted: Sat Oct 01, 2005 8:08 pm
by "Ian Phillips"
Apologies if the answer to this is already in the archives but I just for
curiosity I would be interested to know where Lotus sourced the hardware for
the hinges on the 2 seater doors.

I presume the cup shaped bobbin was specifically made but were the ball
ended nylon screw and the Mazak casting proprietary to Lotus I wonder.

The casting in particular seems to be heavier (costlier) than they could
have devised if they had needed too, so perhaps the whole hinge set had come
from some other piece of equipment. It looks tailored for a GRP structure
(maybe a container manufacturer used them on lids over garbage bins!)

Ian Phillips