Winter Project - Titan LSD project

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CtrMint
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A quick update.

The UJ didn't move at all, all the rotation is in the wheel is at the clamp joint.  It travels from say 12hr to 1hr maximum and only under significant torque such as the dry steering I've described and of course heavy load through a bumpy mountain pass .   I've just been and put fuel in for tomorrow's homeward journey and found the steering dead center again because I've positioned the clamp in the correct position by forcing it back.  

So annoyed with myself, I'm not sure how I've cocked up and ruined the our trip, will certainly have to chalk this one up to experience.  Oddly demonstrates why I have a desire for knowledge and the strategy with the diff as per what the thread is about.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
ChrisC
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For me a Titan owner, the strategy is simple, monitor the pre load and rebuild when the clutches wear out.  If you monitor it regularly you should be able to predict your diffs life and which winter to rebuild it.

I expect that to be about 4 year time for my car.

Apart from that regular spanner checks, that's about it.

Shortshift
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"For me a Titan owner, the strategy is simple, monitor the pre load and rebuild when the clutches wear out.  If you monitor it regularly you should be able to predict your diffs life and which winter to rebuild it."
 
Unless it's the Belleville's or thrust washers that fail (as they do), in which case there's no gradual loss of preload to monitor and every chance of having shrapnel doing the rounds...
 
James
 
ChrisC
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Well in that case, I can't believe I managed 2 seasons already without a problem. Thankfully I have had my plates and bellevilles in my own hands, less than a week ago.

Poor Mark, no strategy for you, until you pander to the haters on the internet.

Shortshift
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"Poor Mark, no strategy for you, until you pander to the haters on the internet."

What a strange and uncalled for comment.

Good luck Chris (and Mark) with your Titan units.  Your experience so far, Chris, is certainly different from mine - but no hate involved. Thumb Up

James

 

David_Long
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I've run Titans for nine years now with no spring failures. I don't want repeat the posts about springs I made in the previous thread, but put simply, if you read up on Belleville's website you'll find they operate well within design limits. The argument put forward about 100% deflection being bad is based on miss-reading / misinterpretation of the parameters  (and there's some evidence that the spring never reaches a 100% as it sits in a dome). The spring life relates solely to the ratio of total deflection to preload deflection. Excessive deflection after the preload deflection is lost is the main reason for failure. So if you keep the preload within limits there is no problem.

Edit to add:

''As a result of manufacturing processes, residual tensile stresses occur at d , the upper inside diameter edge, which will revert to normal compressive stresses when the disc spring is deflected by up to approximately 15% of its total deflection.The fatigue life in applications involving large numbers of cyclic deflections, will be drastically reduced by these stress reversals. For this reason alone, it is important that disc springs used in dynamic applications are pre-loaded to a minimum of 15% of their total available deflection.''

Billy.Whizz
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#52. Mark at least you didn't cock up on thinking of safety first and carrying on thinking it'll probably be ok, so well done for that and I hope you get it sorted soon.

Bill.

ScottR400D
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Yes, it's a shame it ruined your trip but a lesson learned. 

 

7 wonders of th...
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David 

I suggest you fully read the information of the Belleville website as your post is wholly out of context, it appears to be you who is misresding / misinterpreting.

It clearly differentiates between 'Static' and 'Dynamic' applications, stating Dynamic applications should use springs conforming to DIN 2093 - as stated in paragraph 1.

https://www.bellevillesprings.com/disc-spring-selection-and-installation/

Helpful Tips For Selecting Disc Springs

1-If the application involves large numbers of deflection cycles, i.e. ‘dynamic’ application, or if the required forces or deflections are of a critical nature, we strongly recommend that you select from the range of disc springs that conform to the DIN 2093 specification.

 

The link to DIN 2093 is below

https://www.bellevillesprings.com/estimating-fatigue-life/

For clarity the last paragraph is copied below:

Rules of Thumb

1-The pre-load should be a minimum of 15% of available deflection
2-The maximum deflection must not exceed 75% of the available deflection
3-To improve the fatigue life, we can reduce the upper stress or increase the preload or both

Flattening of springs is acceptable in static springs used for instance in a self locking applications.

CtrMint
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Just moving the conversation back to my level Byebye

So far I've purchased;

  • New diff including cradle.
  • Top bolt & nyloc
  • Spacers for the top bolt

besides the oil, is there anything else I should consider sourcing before starting?

Also any advice dismantling?

  • Removing the prop-shaft bolts?
  • A frame, and dedion, I'm assuming that all needs to come out.   Can I keep certain parts together?

Thanks

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com