DMCH Lower ball joints IS THIS WHY THEY FAIL??????

[A Van]

Darren, too funny!!! Very very good!

A humorous post on a very frustrating subject!

[Dan 6511]

What crap the specialT ones are! As mike says there just has to be a cross-ref somewhere.

Does anyone know what the quality of 'Sachs Boge' parts are like? Darren?

[Phil349]

This will be why it felt loose to me because there's so little contact area. The top if the taper does not protrude through the hole when fitted, it ends somewhere inside, so it is not even as good as shown in your pic.
The Elise joints taper measures 14.5 at point B and 16.5 at point C. This means the lower part of the taper is in contact when fitted. Point B is 0.5mm less than on a DMC joint but the taper is still fully inside the hole and the nut tightens down well. So there is plenty more contact using the Elise joint. They seem a good fit and possibly a good option, see what you think when you get it.
I would offer both the special t and the Elise joints up and feel how tight they fit, that's all I did and decided to use them.

There may well be another joint out there that matches the original even better, it's just hard to find them!
Dave H has been trying to source something and had no luck over recent years either.

From what I've heard the original joint is specific to the delorean and DMC have the original drawings. Seems odd though as parts are usually found cross referenced to something else. Maybe we could find the original manufacturer if they are in the UK and get a batch made up? They may still have the details or could possibly work from a goid sample. There will be enough interest I'm sure.

[Darren C]

Hi Dan,

I'm hoping someone will send me one, or for that matter a selection of "old" joints to compare. We may find the DMC joint was a "one off" and there is no true cross reference in which case we have to find the "best" alternative.

Mike,
I'm curious to know what "version" of joints you sent Julian, as you say it's not the same as the one Phil sent me (which I think came from Arran via Special T.

Julian,

Can you post a picture of the ones Mike sent, plus also let me know if your old DMCH joints are Blued please.

To anyone who has a joint which needs a SPACER RING, can you send me one to look at?

Regards
D

[Darren C]

The Elise joints taper measures 14.5 at point B and 16.5 at point C. This means the lower part of the taper is in contact when fitted. Point B is 0.5mm less than on a DMC joint but the taper is still fully inside the hole

Interesting Phil, that means the tapers are still a slightly different angle on the Lotus to the DMC, you could therefore still have a reduced taper lock as a result. ie the bottom of the shaft touches the sides of the hole in the hub but the top has 0.25mm clearance all around, that progressively reduces down to the bottom.

This is not ideal either, as your relying on a clamping effect of the nut and Point C diameter to hold it rather than the taper itself.

Should get my Lotus one in the mail on Monday. Hopefully Julian will be swaping his over this weekend and we'll have some more info.

[arranj]

(which I think came from Arran via Special T.

Not me! I have never spoken to, or dealt with John Hervey... so far at least!


Mike's (now Julian's) ball joints came to the club from Special T Auto in September 2009. These ones never entered the county of Norfolk.

Phil's (now with Darren) ball joints came to the club from Special T Auto in August 2010. They did enter the county of Norfolk when they were brought to the mini meet in October I think, then were sent to Phil in November.


viewtopic.php?f=13&t=490&p=5102#p5102

The DeLorean suspension was designed by Dr.Mike Foxon ex Lotus and I think IDAT - a talented engineer would be an understatement .If Mike's tuned in to this please join in and give us a bit more detail.

The lower ball joint was made by Armstrong Patents Ltd.

Part number 100407

Nick Sutton

[Admin-bloke]

Well done chaps for working together to get to the bottom of this safety related issue.

Has anyone had any discussion with dmch and specialt about this and what warranty or if replacements to spec are available for warranty returns?

[Phil349]

Possibly yes, although the shaft on the elise joint is longer to take into account how it reduces further towards the top, but not too long as to come through the top of the hole when fitted.
Its definately a compromise, but the shaft fitted better than the special T joints and I was able to machine the cir clip groove correctly, so I used them. But they may not be 100% the perfect ones to use, there may well be something else we could find thats better.

[Phil349]

I cant find any info on Armstrong Patents, I think they are long gone.

The other thing to think about is both the special T and Elise joints do not have a grease channel on the ball, the DMC one does. As well as being able to pump more grease into the DMC joint.

Have you heard anything back from DMCH regarding the blueing?

[arranj]

Yes, sadly Armstrong Patents is no more: http://www.armstronglyon.com/history.php

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Also made helicoils!: