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never wheeled
April 30th, 2010, 10:41 AM
I read a very informative article on fasteners in Dirt Sports yeaterday. Seems my suspicions that my budget has been sending me the wrong way. The way the article reads Grade 8 is a minimum and unreccomended for Chassis and Crucial points. F911 is the standard. The thing that REALLY caught me off gaurd was Thread Lube. Used plenty of Thread Loc but never Thread lube. Aparently this is as Crucial as Proper Torque Spec for optimum Strength and Holding power. Needless to say I'm getting pricing on F911 hardware and Lubing and re-torquing all of my Main components, its snowing anyway...

scottycards
April 30th, 2010, 11:57 AM
<skeptical>

Grade 8 has been used in automotive applications and racing for years. I used to sell bolts, and while the thread lube info is accurate, I believe the F911 benefit to be possibly overstated.

I used to sell yellow chromate Grade 8 hardware to a shop here in Denver that has won a few World Challenge series, etc. Big time Porch racers and the like, even ALMS. 3R Racing.

If the cost is similar, maybe it makes sense in extremely high performance, critical applications, but showing any kind of ROI or benefit on this, unless you're suffering multiple, repeated Grade 8 failures, is probably not going to happen.

Never hurts, tho. Post up cost differentials and your experience with it. Very interesting, for sure. You'll be surprised at the difference in torquing a lubed bolt vs. unlubed.

:thumbsup::thumbsup:

Steve
April 30th, 2010, 12:48 PM
You'll be surprised at the difference in torquing a lubed bolt vs. unlubed.

Very true. In many critical industrial applications the torque spec is given wet or dry. Torquing a nut/bolt stretches the bolt. Torquing wet stretches the bolt farther than torquing dry. Sometimes that is a good/desired thing, sometimes not. Assuming that all torque specs are wet is incorrect.

CSP
April 30th, 2010, 03:59 PM
Sometimes that is a good/desired thing, sometimes not. Assuming that all torque specs are wet is incorrect.

Thank you Steve for bringing this up. This was my first thought when I read the OP. If something is supposed to be torqued wet, the torque spec usually says so.

One size does not fit all.

never wheeled
May 1st, 2010, 10:20 AM
I used to sell yellow chromate Grade 8 hardware to a shop here in Denver that has won a few World Challenge series, etc. Big time Porch racers and the like, even ALMS. 3R Racing.

You wouldn't happen to have a torque spec sheet for Gr8 lubbed and unlubbed would you?

Assuming that all torque specs are wet is incorrect
Then should you assume that they are Dry if unspecefied? If lube is an industry standard how do you know wet or dry. If lube is the standard shouldn't you assume wet for torque spec? just asking. I imagine the best is to get a chart that specefies both...

I haven't ever had a Gr8 fail but.. The car is literally twice as fast as it used to be from 300 to 600 hp 800#s less weight better suspension ect. I don't want to find out that Gr8 is only good for 80mph at 100. Also don't you think that it is a little bit of a stretch comparing ANY street or road racing to off road stuff? I mean we break 3000hp rear ends with tired 22r's. The shock loads that an off road suspension sees are completely out ot the stratosphere compared to a road car. Even an F1 pulling 4-5 g's isn't going to compare to the load of casing a whoop at 50mph not even close...just the dynamic loads created by 1-2 foot washboard would boggle a road race engineer.
I probably should've mentioned as well that my car is more of an Ultra 4 than a pure rock crawler. It was actually built as a pre-runner for that type of racing before there even was ultra 4. that being said I'm not the only with a car set up this way. Most people have realized that these vehicles are truely all terrain and are fun no matter where you go if you build them right. The consequence of testing Gr8 bolts at 5mph is negigable more than likely its just going to cost money and time to fix. Failure at 100mph is a completely different story...

Steve
May 1st, 2010, 10:29 AM
Then should you assume that they are Dry if unspecefied? If lube is an industry standard how do you know wet or dry. If lube is the standard shouldn't you assume wet for torque spec? just asking. I imagine the best is to get a chart that specefies both...

I took a class years ago from a fastener company on this exact topic. IIRC they said to assume that torque specs are dry unless specified otherwise. I suspect that for most of what we do it isn't terribly critical. For things like head bolts, it does matter; most manuals say to lube those before installing, so the torque specs for them are wet.

shotgunchris
May 1st, 2010, 11:56 AM
You wouldn't happen to have a torque spec sheet for Gr8 lubbed and unlubbed would you?

I printed this out, page 2 has what you're looking for: http://www.imperialsupplies.com/pdf/A_FastenerTorqueCharts.pdf

NismoFreak
May 1st, 2010, 12:59 PM
I read a very informative article on fasteners in Dirt Sports yeaterday. Seems my suspicions that my budget has been sending me the wrong way. The way the article reads Grade 8 is a minimum and unreccomended for Chassis and Crucial points. F911 is the standard. The thing that REALLY caught me off gaurd was Thread Lube. Used plenty of Thread Loc but never Thread lube. Aparently this is as Crucial as Proper Torque Spec for optimum Strength and Holding power. Needless to say I'm getting pricing on F911 hardware and Lubing and re-torquing all of my Main components, its snowing anyway...

Was the article written by the f911 company? Kinda seemslike a marketing scare tactic

never wheeled
May 1st, 2010, 03:02 PM
Was the article written by the f911 company? Kinda seemslike a marketing scare tactic
It was written by a wel known off road engineer. His concern was geared toward safety, It is a magazine so the easiest way to have an artice on bolts is for a bolt company to buy some advertising. I'll check through and see if there are any full page adds from Bolt suppliers.None the less there is some validity to the arguement. I'm waiting for pricing from a supplier who ironically recently solicited me for business. I'll post the two price lists for Gr8 and F911 or L9 is what they call it.

Thanks for all the info everyone I think this thread has some meritt. Hope we can all build better cars as a result.

scottycards
May 1st, 2010, 03:21 PM
Great thread. Assume dry unless spec'd wet.

I couldn't agree more- peace of mind is worth extra cost. I'm that way as well. I over prep and over kill a lot of things on the car I race. I wear safety gear that's not required, etc.

One person can crash at 100 and walk away. The next guy crashing at the same speed might not live. It's a crap shoot sometimes.

I also agree that off road racing is probably the top of the abuse/stress totem pole on parts and fasteners.

never wheeled
May 3rd, 2010, 03:59 PM
Imperial Fasteners has stopped carrying F911 hardware I'm finding another source for price comparrison.

never wheeled
May 4th, 2010, 10:50 AM
Pricing
GRADE 8
http://www.allensfasteners.com/search_results.asp?txtFromSearch=fromSearch&txtsearchParamType=ALL&txtsearchParamMan=ALL&txtsearchParamVen=ALL&iLevel=1&subcat=&txtCatName=1&txtsearchParamTxt=&CatSource=72..1&txtsearchParamCat=72

F911
http://www.allensfasteners.com/search_results.asp?txtsearchParamTxt=&txtsearchParamCat=73&txtsearchParamType=ALL&iLevel=1&txtsearchParamMan=ALL&txtsearchParamVen=ALL&txtFromSearch=fromSearch&btnSearch.x=9&btnSearch.y=6&gclid=CMbH95PkuKECFR5rgwodpUIaAQ

So for suspension Mains as a comparrison.
A 9/16 x 6 18 F911 bolt costs 7.44 each
A 9/16 x 6 18 GR8 bolt costs 1.76 each
F911 hardware costs 4.22x more than GR8 so I guess its much Cheaper to just make sure the GR8 stuff is overkill.
I will more than likely replace the suspension Mains, shock hardware,motor mounts and seat bolts and leave it at that. It will cost me about $160 to do that and the insurance is worth it.
On another note about GR8. Nick (Xtreme Engineering) wiped out his Buggy at 70+ mph at walden a while ago. He and the passanger were strapped in and walked away, fortuneately, so did his buggy(minor body damage and a broken bump stop). None of the GR8 stuff broke. He bent 1 and replaced the rest but none failed. He nosed then cartwheeled so a lot of G's on the suspension. GR8 is proabably enough.

chad
May 18th, 2010, 02:42 PM
http://www.race-dezert.com/forum/showthread.php/47838-F911-Bolt-Failure

never wheeled
May 20th, 2010, 07:15 PM
Great thread Chad.

Re: F911 Bolt Failure
Also in torquing a fastener there are several things that need to be done properly according to the aircraft spec.
First always use some sort of thread lubricant, second find out what your run on torque is with a dial torque wrench. Third torque the nut if there is one, but either way torque back off and then re-torque. This is how it is specified the the aircraft industry.
If you are using a self locking nut remember that you can use them over but depending on the nut being used there is a life cycle of the locking feature. Some nuts for instance ms21043 series are only good for 3-4 cycles and then the locking feature is not sufficient for use.

Hope this helps you out.
From that RDC THread