Tearing hair out section - window cables!

[elansprint71]

Brian Buckland gives a detailed description of assembling the window in his book. This may be useful.

With one of the (very) few errors I've found in his book- the number of turns around the drum!

[billwill]

Long long ago (probably when I bought my very first replacement window cable) I was given these three sheets of fitting instructions. They have been my Bible for window fitting ever since.

It is poorly explained in the official Lotus manual, so I think it is fitting that I post them here.

[billwill]

OOPs why did the pictures not appear ???

I thought I had uploaded the pictures to this site, but they did not appear.

Never mind I put them on my server and linked them in above.

[vintrace]

Very impressive aray of answers... all I can think of adding is that to anneal your copper washers you need to heat them till the flame goes green them quench them in water... don't try for red hot they will disapear.. Boy all this good stuff I almost want one of my windows to fail...

[oldelanman]

It is poorly explained in the official Lotus manual, so I think it is fitting that I post them here.

Bill, I don't know which version of the Workshop Manual you have but your instructions are pretty much word-for-word the same as what's in my manual with a couple of notable exceptions.........

The manual shows additional washers on the clamp stud and a lower torque figure for the nut - presumably later revisions to reduce the risk of breaking the glass. There are 5 washers shown in the manual arranged as follows....nut, steel washer, plastozote washer, glass, plastozote washer, steel washer, copper washer, cable, stud head. The copper washer no longer bears directly on the glass. The nut torque is 4 lb ft whereas your instructions say 6 lb ft.

Brian Buckland's book also contradicts the Workshop Manual as he show three washers - fibre, copper and steel - and quotes 6 lb ft for the nut torque.

I guess it's your choice which set-up you use but the Workshop Manual would get my vote as being the least likely to result in a broken window!!

Regards,

[robertverhey]

Replacement cable? go to the shipchandlers and ask for running rigging (as opposed to standing rigging). Very bendy.

[billwill]

Ah, interesting. I have two versions of the manual and the later one does include that description above word for word including the single fibre washer and a torque of 6 ft lbs.

[AussieJohn]

A mate of mine used a similar arangement like Ralphs but made a miniature turnbuckle in the longest run for tensioning, looks good!

[fasterbyelan]

It is poorly explained in the official Lotus manual, so I think it is fitting that I post them here.

Bill, I don't know which version of the Workshop Manual you have but your instructions are pretty much word-for-word the same as what's in my manual with a couple of notable exceptions.........

The manual shows additional washers on the clamp stud and a lower torque figure for the nut - presumably later revisions to reduce the risk of breaking the glass. There are 5 washers shown in the manual arranged as follows....nut, steel washer, plastozote washer, glass, plastozote washer, steel washer, copper washer, cable, stud head. The copper washer no longer bears directly on the glass. The nut torque is 4 lb ft whereas your instructions say 6 lb ft.

Brian Buckland's book also contradicts the Workshop Manual as he show three washers - fibre, copper and steel - and quotes 6 lb ft for the nut torque.

I guess it's your choice which set-up you use but the Workshop Manual would get my vote as being the least likely to result in a broken window!!

Regards,

I have just stripped down a window, the car is only a few months newer than Stuart's. There are only 3 washers fitted, the same as Brian describes. I believe the cable has never been replaced.

On a similar theme, the parts manual list a plastic sheet, inner door (part no. 036 B 0675).
Does anyone know where this is fitted, its shape ect ect ?

[69S4]

Right, I've had a closer look at the clamping bolt arrangement and think I've worked out why the cable pulled through. It was assembled as per the diagram that BillWill posted earlier, namely clamp stud - cables - copper washer - window glass - fibre washer - nut.

However there are a couple of odd things with the hole in the window. Firstly, it's quite a large hole - just under 8mm diameter, so the 1/4" clamp bolt has a lot of clearance. Secondly, there is a 1mm chamfer on both sides round the hole. Looking at the fibre and copper washers it seems that they've both distorted into the gap over time and therefore reduced the clamping force on the cables. The torque on the nut had reduced to close to zero.

I suppose I could add a few more washers to pad it all out and lengthen the time it takes for the tension to drop but that's obviously not the real answer. I can visualise a few solutions ranging from replacing it all to making new parts but unfortunately there is a gap between what I can visualise and what I have the facilities to make. Any help / suggestions gratefully received.

[oldelanman]

Hi Stuart,
What you have found may just be the reason that the later revision to 5 washers was made. The steel washers provide a flat surface for the nut on one side and the copper washer on the other side to bear against and the plastic washers protect the glass. This must produce a more rigid assembly than having fibre and copper washers directly in contact with the glass, particularly if the stud is not a close fit in the glass as you have found. If you do use this arrangement, I would not worry about the clearance you have through the glass so long as your plastic and steel washers are a close fit on the stud and with an O/D large enough to cover the gap. You can make suitable plastic washers from an ice cream tub if you can't buy anything suitable.

Regards,

[elansprint71]

Should there not be a thick fibre washer fitted into the hole in the glass? i.e. about 8mm o/d and 6mm i/d. This takes up the space between the bolt and the hole in the glass; that's what I have in mine.

[billwill]

All this is somewhat academic because our Alex Black, member here, has invented a much better system in which the securing force for the cable is independent of the pressure which the nut applies to the glass.

A headed bolt with nyloc nut is bolted through the glass using suitable fibre padding washers.
The hole for the cables is drilled sideways through the HEAD of the bolt. (the cables are not in contact with the glass or any washers)
The bolt is drilled and tapped down its axis.
A tiny hex socket grubscrew is screwed down from the nut end to the head end to secure the cables.

It is not anticipated that the grubscrew could come loose, but anyone who thinks it might could put some Loctite on the grubscrew.

[69S4]

All this is somewhat academic because our Alex Black, member here, has invented a much better system in which the securing force for the cable is independent of the pressure which the nut applies to the glass.

If Alex reads this and has any of his bolts available for sale I'd be only too happy to cross his palm with silver (or any other coin of the realm!).
I've looked back through the posts he made last year and it would certainly seem to be the way to go.

Should there not be a thick fibre washer fitted into the hole in the glass? i.e. about 8mm o/d and 6mm i/d. This takes up the space between the bolt and the hole in the glass; that's what I have in mine.

I don't and never have had something like that in the clamp assembly but it did occur to me that a collar slightly thicker than the glass (I imagined it in steel) would enable the bolt to be done up tightly without putting any stress on the window. Again, lack of facilities to make the parts has been the stumbling block.

[alexblack13]

Aye they work well.The grub screw down tho' the bolt which secures the cables dos not need much torque.and the cables will not pull through. I also included another grub on top as a locker so no need for the locktite.The screw dia if I remember is m4..

I have mad a fair few of them for folks various but as of now (I will have a looksee) I am not sure if I have any of the components left. I will let you know... If I do make some more Payment will not be required. But a donation to BHF will be required.. Just a wee one though... + postage!!

Failing that I could do a little sketch for you all...

I broke two window glasses before I said bugger this for a laugh so a wee mod was required... Foolproof. Even Ecky proof!! ... Have fun all you perseverers...Makes a fair bang when the glass goes off!! TIP... Make a pattern from hardboard of the glass before you break it!! I saw it coming and made one 1st and good job I did..

Alex...