Pinning a crankshaft.

[JasonBModerator @jasonb]

Posted by Martin Kyte on 05/07/2016 08:43:35:

Just an observation that so far, unless I missed something, everyone has described methodology that has worked which tends to indicate all methods are sound. What would be more instructive would be any information on failures on the basis that it's useful to know what you have to do better than. I guess it's the old 'you learn more from your mistakes than your successes.

regards Martin

A good point Martin, on some of the other forums where there are a lot more members who get out in there workshops and build things I have read of several instances where loctited cranks have failed but don't recall any pinned ones failing. Whether this is down to the product not being upto the job or incorret use/execusion. This is why I went with the tried and trusted method that has worked on these engines in the past

[JasonBModerator @jasonb]

Posted by Michael Gilligan on 05/07/2016 08:23:02:

Using the same 'inputs', I would have concluded that a 'bond' which is fully distributed over the joint area would be more resistant to the kick, and would therefore have used either a fully silver soldered joint, or [more likely] Loctite 638.

Micheal see earlier about knowing if the joint is fully penitrated and keeping the bearing surfaces free of solder. I have also made cranks that are fully soldered and its a pain to clean the solder off particularly the pin if you want to avoid removing steel as well as solder, little point in using precision ground material and then running a file over it.

[Michael GilliganParticipant @michaelgilligan61133]

Understood, Jason

That's why my choice would be "[more likely] Loctite 638"

MichaelG.

.

P.S. Regarding Martin's excellent point, and your response: It would be very useful if you could post details of any "Loctite failures" that you see mentioned.

[JasonBModerator @jasonb]

Post 67 & 68 for construction and post 178 for failure. This chap is more than just a beginner, his work looks to a good standard and an engineer by trade not an amatuer like me.

It's now running OK with pins in the joints.

Edited By JasonB on 05/07/2016 09:42:32

[JasonBModerator @jasonb]

Loctie & pin failure here

I really should be working so you will have to go looking for more

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, Jason … Very interesting, although I think your 'failure' reference should point to #173 not #178

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by JasonB on 05/07/2016 09:54:06:

Loctie & pin failure here

.

Thanks again, Jason

Unfortunately, that one is of no 'forensic' value, because he does not specify which 'Loctite' he used.

See Danny's current thread **LINK**

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Reference Jason's first example:

The builder used Loctite 620 **LINK**

This is specified/tested to ISO 10123 **LINK**

MichaelG.

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