RobH Posted March 26, 2018 Report Share Posted March 26, 2018 Hi Bob, you can talk ft/lbs but you must Torque lbs/ft Roger (pedantic hat on) Torque in pounds-per-foot Roger ???? Surely its lb.ft (sorry - pedantic hat off) It certainly is unusual to specify oiling but perhaps they have reduced the torque to take account of that? Quote Link to post Share on other sites
RogerH Posted March 26, 2018 Author Report Share Posted March 26, 2018 Hi Rob (Hawkeye), I normally refer to ft/lbs for force and lbs/ft for torque but as you have spotted this is not correct because it should be a multiplier not a divider. The backslash should be a (.) dot or (*) asterix. Working on the idea that you are the only person in the whole universe (I'm ignoring parallel universes) that would spot it I'm sticking with my imperfection. Roger Quote Link to post Share on other sites
brian -r Posted March 26, 2018 Report Share Posted March 26, 2018 Roger You do know the use of SPRING washers is time critical. Do not fit during summer ,autumn or winter, this may be your problem :) Bri Quote Link to post Share on other sites
RogerH Posted March 26, 2018 Author Report Share Posted March 26, 2018 Hi Brian, all this time I have underestimated your wisdom . Many thanks great sage. Roger Quote Link to post Share on other sites
Lebro Posted March 26, 2018 Report Share Posted March 26, 2018 (edited) It certainly is unusual to specify oiling but perhaps they have reduced the torque to take account of that? Well no - they had not - still 95 - 105 lb.ft which is standard Bob. Edited March 26, 2018 by Lebro Quote Link to post Share on other sites
ChrisR-4A Posted March 26, 2018 Report Share Posted March 26, 2018 Hi Bob, I did see your question. What does the WSM say? Just looked - it says nothing. The head needs to remain tightened down. Any thread lubricant will reduce the thread friction. I would suggest 'dry fit' Roger Completely dry is not a good idea as it is clampload which seals the head gasket obtained by tension in the studs. If friction between the stud and nut causes the torque wrench to shut off early before sufficient clampload is attained then the joint will be compromised.A very light coating of thin oil applied with a brush or spray can should be fine. Chris Quote Link to post Share on other sites
Chris59 Posted March 27, 2018 Report Share Posted March 27, 2018 Spring washer on a rocker shaft pedestal stud ? Not in my engines, Roger ! Quote Link to post Share on other sites
RogerH Posted March 27, 2018 Author Report Share Posted March 27, 2018 (edited) Spring washer on a rocker shaft pedestal stud ? Not in my engines, Roger ! Hi Chris, Indeed. I have only just spotted that is missing in the Moss WebCat. They have been there for the last 20 years. I shall use some neat aerospace stiff nuts. https://www.lasaero.com/products/article/CUB8AQL Roger Edited March 27, 2018 by RogerH Quote Link to post Share on other sites
Steve Priest Posted April 4, 2018 Report Share Posted April 4, 2018 Hi Chris, Indeed. I have only just spotted that is missing in the Moss WebCat. They have been there for the last 20 years. I shall use some neat aerospace stiff nuts. https://www.lasaero.com/products/article/CUB8AQL Roger Hmm, interesting. I was just about to Google "stiff nuts" to find out more - then decided that might not be a good idea. Steve Quote Link to post Share on other sites
RogerH Posted April 4, 2018 Author Report Share Posted April 4, 2018 Hi Steve, why would 'stiff nuts' not be a good idea. Spring washers are not stated by Moss but I have 20 years proof that they work - even with a plain washer between pedestal and SW. The aerospace stiff nuts do work very well on aero engines and with plain washer. Roger Quote Link to post Share on other sites
RobH Posted April 4, 2018 Report Share Posted April 4, 2018 (edited) Roger I think you have underestimated the power of the internet to find dodgy things. That is what Steve was implying I think, not that there was anything wrong with the nuts. Being somewhat interested in the radiation properties of hot surfaces at one time, I made the mistake of Googling 'black body'. The results were illuminating. Edited April 4, 2018 by RobH Quote Link to post Share on other sites
RogerH Posted April 4, 2018 Author Report Share Posted April 4, 2018 Hi Rob, I have tried googling for any good information about the spring washers but can only find very negative thread. Quite a few posts gave in-depth 'facts' that in my mind were utter cods wollop. There was one post showing that ALL friction devices were rubbish. They applied a Junker vibration rig to all and every type of friction locking mechanism - nyloc, sprig washer etc etc and then hit them with their resonant frequency. Off course they came undone - its physics. But by the same token if you design out the resonant frequency then they will lock. Roger Quote Link to post Share on other sites
ed_h Posted April 4, 2018 Report Share Posted April 4, 2018 Once upon a time, I did the same research program, Roger, and found about the same as you did. It seems that at best, split washers contribute little or no significant locking effect under some conditions, and may even be worse than nothing. I read that NASA and and least two branches of the US military don't allow split lock washers for many or most applications. I'm moving to Nylocs with a flat washer for most low temp applications. Ed Quote Link to post Share on other sites
DaveN Posted April 4, 2018 Report Share Posted April 4, 2018 Oh dear someone better tell Mr Royce as he uses spring washers on his aero engines in some places and..... shock horror Mr Royce along with Mr GE and Mr Boeing all use..... wait for it......helicoil inserts in alloy bolted parts!! Quote Link to post Share on other sites
john.r.davies Posted April 4, 2018 Report Share Posted April 4, 2018 NASA was - is? - famous for the Saturn V, which had a failure rate for parts of less than 0.01%, but as there were 6 million parts. that meant 6000 would fail per mission. Maybe banning split washers had someting to do with that Although it was either Alan Shepherd or John Glenn, who wondered why he was sitting on a firework with two million parts (Redstone), all built by the lowest bidder. John Quote Link to post Share on other sites
Steve Priest Posted April 4, 2018 Report Share Posted April 4, 2018 Hi Steve, why would 'stiff nuts' not be a good idea. Spring washers are not stated by Moss but I have 20 years proof that they work - even with a plain washer between pedestal and SW. The aerospace stiff nuts do work very well on aero engines and with plain washer. Roger Sorry, puerile humour. Genuinely not heard of them before. Steve Quote Link to post Share on other sites
BlueTR3A-5EKT Posted April 5, 2018 Report Share Posted April 5, 2018 ...but how does using a stiff nut affect the torque setting. (Reverse of oiling the thread) Is this why there are graphite coated thread types of Kaylock nuts? https://k-nuts.com/index.php/contact-us/download-k-nuts-catalogue/ Peter W Quote Link to post Share on other sites
RogerH Posted April 5, 2018 Author Report Share Posted April 5, 2018 Sorry, puerile humour. Genuinely not heard of them before. Steve Hi Steve, I completely missed that one. I shall try harder - I'm normally good with puerile humour. It's an age thing. Roger Quote Link to post Share on other sites
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