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Thor-bob Tue Aug 11, 2015 3:36 pm

ALIKA T3 wrote: Isn't the washer split from factory?

Hard to say.....

It has a ragged surface at the split as if it had failed in hoop stress.

The nut has two surfaces on the business end:
The outer half is flat
The inner half is a 60 degree cone

Normally a cone is used to create a certain level of friction, like a Morse Taper

The washer has a 60 degree surface that mates to the inner cone on the nut - this would cause enormous stress under normal use. Perhaps the washer was made with insufficient cone diameter, leading to this failure.

I suspect that the cone portion of the nut was used to center the washer under assembly.

A lower stress design would be to make the washer seat fully on the flat outer nut half, and keep the cone for centering. I will make one on the lathe of UHMW Plastic and try it out, then report back.

If this pans out, maybe Terry would like the shop drawing and start making some for all you late vanners...

Thor-bob

Thor-bob Tue Aug 11, 2015 11:44 pm

Okay.......... did it, and it works.

Tightened the nut so the threads were about flush with the top.

Pics as follows:







Locktite is drying ..... will know final result tomorrow.
*******************************
It's now later - mirror works great

Thor-bob

afmercure Mon Sep 07, 2020 1:33 pm

In case it can help anyone struggling with this... Had the same problem today.

Like RaxAdam, I could not manage to screw the nut when the mirror was attached to the door - the spring and the wires made things too hard.

So I removed the mirror and carefully squeezed it in my wooden bench vise, from where I could take wires out of the way and apply enough pressure on the spring/nut to get the nut back in place:





To remove the mirror, I removed the door panel, removed individual spade connectors from plugs and pulled wires through the door, as explained in the Bentley (pages 62.x).

khughes Mon Sep 07, 2020 5:25 pm

Thor-bob wrote: ALIKA T3 wrote: Isn't the washer split from factory?

Hard to say.....

It has a ragged surface at the split as if it had failed in hoop stress.

The nut has two surfaces on the business end:
The outer half is flat
The inner half is a 60 degree cone

Normally a cone is used to create a certain level of friction, like a Morse Taper

The washer has a 60 degree surface that mates to the inner cone on the nut - this would cause enormous stress under normal use. Perhaps the washer was made with insufficient cone diameter, leading to this failure.

I suspect that the cone portion of the nut was used to center the washer under assembly.

A lower stress design would be to make the washer seat fully on the flat outer nut half, and keep the cone for centering. I will make one on the lathe of UHMW Plastic and try it out, then report back.

If this pans out, maybe Terry would like the shop drawing and start making some for all you late vanners...

Thor-bob

Those washers are now available from uniWerks Design for cheap, and they work! :D

https://www.uniwerksdesign.com/product/power-mirror-spring-bushing-vanagon/



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