PaulD Posted September 6, 2005 Share Posted September 6, 2005 Stay away guys! Working in an industry where somebody asks - at least - once a year; can we use Ti fasteners, the answer is NO! Ti has about 60% the density of steel, but it also has about 60% of the strength, so there are no gains to be made there - you need a bigger Ti fastener to replace a steel one and on the whole you lose out because you need to make everything else bigger to take the bigger fastener. Even worse, Ti - like aluminium, but unlike steel - does not have a fatigue limit. With steel there is a stress - about 0.5 Fty - below which the fatigue life is infinite. With Ti, the S-n curve is asymptotic to zero stress i.e. any Ti component, however lightly stressed may experience fatigue failure. Generally, there are no Ti fasteners on F1 cars. Don't put them on road cars! MP35N Cobalt is another story! Paul Link to comment Share on other sites More sharing options...
John Howe Posted September 6, 2005 Share Posted September 6, 2005 Paul, thanks for that little gem of information - now we know why they are not allowed on race cars. Guess you can now count me out... JH Deliveries by Saffron, the yellow 230bhp Sausage delivery machine Link to comment Share on other sites More sharing options...
Phil Posted September 6, 2005 Author Share Posted September 6, 2005 PaulD Thanks for your comment, very interesting. How do these people get away with making and selling them if this is the case, or is the Titanium alloy different from the std Titanium you use? X/FLOW 1700 DD 1990 ROAD USE ONLY..SO FAR Link to comment Share on other sites More sharing options...
Pierre Gillet Posted September 7, 2005 Share Posted September 7, 2005 PaulD I would have thought that the sizing of steel F1 parts is already optimized and that, indeed, replacing steel by titanium means increasing thicknesses etc. by 40 %. In the case of our Caterham, the question woould be :is the SS nuts sizing already optimized ? If it is not the case, replacing steel by titanium while keeping the same sizing might be OK What is exactly MP35N Cobalt please ? Pierre Edited by - Pierre Gillet on 7 Sep 2005 09:53:41 Link to comment Share on other sites More sharing options...
Slow Hida Posted September 7, 2005 Share Posted September 7, 2005 I work for a company specializing in the manufacture of high strength fasteners for all levels of Motorsport. In an attempt to clarify the potential use of titanium fasteners on road cars I would offer the following :- 1) There is a lot of titanium fasteners used at the highest levels of Motorsport, although the FIA in its wisdom has banned the use of ti fasteners in F1 engines next year. This decision was based on cost. To give an idea on useage about 60% of our output goes on an F1 engine or chassis and 25% of that output has been in titanium fasteners. 2) Ti fasteners can be made to the same strength as steel, but the material needs to be carefully specified, threads need to be warm rolled, features need to be forged and not machined, etc etc – oh I could go on for hours ( as anyone at the Worcs Club will confirm) Typically ti fasteners like a nice static load after installation and do not like cycling. Therefore it is not usual to see ti bolts being used as rod bolts, although there have been some notable exceptions. Where the use of ti is permitted builders have even used ti for wheel studs. However this is based strictly on limited life and parts are usually serial numbered. 3) Illegally fitted ti parts are easily spotted by scrutineering as it is not magnetic. However the lure is strong as major weight savings can be made for reasonable costs. –ti is 60% the density of steel. Some big budget winners, in formulas where ti is banned, have been known to use ferric plasma sprayed ti parts, in order to overcome the non magnetic problem!!! 4) There are major problems using ti fasteners in every day applications, particularly where there are repeated installations. Ti threads tend to “gall” or pick up during installation, this problem is likely to get worse with each installation. This means that a bolt or a nut can be torqued up correctly but the thread has picked up, the torque is dissipated in overcoming the friction and the joint is not clamped correctly. This would be a particular issue on old studs that had some distortion, chaffing and dirt present though use. Hope this helps Slow Hilda aka Tony Baker - Northbridge Motorsport A7 JXM Link to comment Share on other sites More sharing options...
Phil Posted September 7, 2005 Author Share Posted September 7, 2005 Ok then, what about RAYS ENGINEERING wheel nuts made from DURALUMINUM. 0.8 oz what does this convert to in grams please. X/FLOW 1700 DD 1990 ROAD USE ONLY..SO FAR Link to comment Share on other sites More sharing options...
SimonMac Posted September 7, 2005 Share Posted September 7, 2005 0.8oz = 22.68g Link to comment Share on other sites More sharing options...
Pierre Gillet Posted September 8, 2005 Share Posted September 8, 2005 What about the ss nuts used for the spare wheel ? They weigh 20 g less than the regular one , so their weight should be around 33,5 g .here Pierre Link to comment Share on other sites More sharing options...
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