FYI... TireRack's statement on anti-sieze and lugbolts ....
01-18-2002, 09:46 AM
#22
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I am looking into this...
The makeup of the anti-seize I use is a varation on one of the popular non-electrical-conducting ceramis based thermal compounds on the market. I have asked the manufacturer for information on the anti-seize thermal conductivity.
Thermal compounds are not as efficient at conducting heat between two surfaces as two perfectly mated surfaces, but that almost never happens in real life. Where there are gaps in the mechanical connection, thermal compound improves heat transfer (its better than air). This describes the contact areas between the wheel and rotor pretty well. The question is what is the conductivity of the anti-seize...
One other point. Most electrical engineers appreciate that a little thermal compound is a good thing and a lot is a bad thing as it can actually hold the surfaces apart rather than just fill the voids and as I said even these thermal compounds are not as efficient as a perfect metal-metal mating. This would hold true for the anti-seize as well. A little will help fill voids and provide a thin barrier between the wheel and hub, a lot will certainly separate the surfaces and decrease the heat transfer just as it would if it were a good thermal compound applied too thickly.
Thermal compounds are not as efficient at conducting heat between two surfaces as two perfectly mated surfaces, but that almost never happens in real life. Where there are gaps in the mechanical connection, thermal compound improves heat transfer (its better than air). This describes the contact areas between the wheel and rotor pretty well. The question is what is the conductivity of the anti-seize...
One other point. Most electrical engineers appreciate that a little thermal compound is a good thing and a lot is a bad thing as it can actually hold the surfaces apart rather than just fill the voids and as I said even these thermal compounds are not as efficient as a perfect metal-metal mating. This would hold true for the anti-seize as well. A little will help fill voids and provide a thin barrier between the wheel and hub, a lot will certainly separate the surfaces and decrease the heat transfer just as it would if it were a good thermal compound applied too thickly.
01-18-2002, 09:55 AM
#23
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i memorize torque pressures and know exactly how much effort to put with either arm(s), finger(s)
i havent used my industrial grade leg press torque method on this car yet. =)
01-18-2002, 10:09 AM
#24
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Which anti-sieze do you use?
A friend of mine recommended the Griot's stuff, which seems to be a ceramic anti-sieze in a synthetic oil carrier. I searched around for something similar, but cheaper, because the ceramic stuff seems "less messy" to deal with vs. the metallic compounds. I didn't find anything, so I went ahead and picked up the griot's anti-sieze.
Just wondering where you got yours, and for how much. I'm sure this stuff is available for less elsewhere, I just haven't found it. I think the Griot's is $15 for a little bottle (4 oz?).
TIA
Just wondering where you got yours, and for how much. I'm sure this stuff is available for less elsewhere, I just haven't found it. I think the Griot's is $15 for a little bottle (4 oz?).
TIA
01-18-2002, 04:02 PM
#26
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So, this is what I have learned today...
1) Auditalk is useless (duh).
2) It is most likely that the factory supplied wheel bolts (m14x1.5x27.5 in my case) is a 133,000 psi strength grade 6 or 7 bolt. This is based on finding a site that actually lists 89 lbft as the recommended dry torque for the above bolt.
3) If it is the above the MAX recommended torques are 150 lbft dry and 110lbft oiled.
4) The tirerack supplied bolts with my SSR Integrals are cad or zinc plated. This accorrding to one site reduced the required torque by 25% all by itself. I bet Tirerack didnt tell you that, did they? They didnt tell me. Also adding oil doesnt necessarily lower it appreciably (the friction reducers like plating and oil dont simply add).
My conclusion. Unless Tirerack is supplying us inferior fasteners, tightening to 89lbft with a anti-seize lubed bolt isnt going to hurt the bolt. That is still 21lbft below the grade 6-7 bolt max lubed torque. Now, if they supply below grade 5 (120,000 psi) it is an issue.
2) It is most likely that the factory supplied wheel bolts (m14x1.5x27.5 in my case) is a 133,000 psi strength grade 6 or 7 bolt. This is based on finding a site that actually lists 89 lbft as the recommended dry torque for the above bolt.
3) If it is the above the MAX recommended torques are 150 lbft dry and 110lbft oiled.
4) The tirerack supplied bolts with my SSR Integrals are cad or zinc plated. This accorrding to one site reduced the required torque by 25% all by itself. I bet Tirerack didnt tell you that, did they? They didnt tell me. Also adding oil doesnt necessarily lower it appreciably (the friction reducers like plating and oil dont simply add).
My conclusion. Unless Tirerack is supplying us inferior fasteners, tightening to 89lbft with a anti-seize lubed bolt isnt going to hurt the bolt. That is still 21lbft below the grade 6-7 bolt max lubed torque. Now, if they supply below grade 5 (120,000 psi) it is an issue.
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