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pmnewlon

Well Known Member
My narrow deck O320-B2B requires non-AN hardware for several things I am working on. I need (4) 5/16-18 x 1.25" hex head bolts - Lane Aviation wants $28 each for them! I need one 5/16-18 x .75, it is $3. 1/4-20 nuts (STD-1411)? Nada. 1/4-20 x 1.50" (STD-1414)? Nada.

What does one do for finding this kind of hardware? I tried http://www.gen-aircraft-hardware.com and Aircraft Spruce but couldn't find what I was looking for.

Thanks! Phil
 
Have you tried NAPA? They had some studs that I needed and were quite a bit less expensive that the normal Lycoming parts distributors. Just don't tell them what engine you're planning on installing the bolts you're looking to find.

bob
 
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The hardware that Lycoming uses is actually grade 5. Grade 8 is more than adequate. AN hardware can be used as well. Tractor Supply sells grade 8 by the pound, so thats where I go for coarse-thread hardware.
 
You guys rock, of course. Is it safe to say that if I can't find something I need in the AN spec hardware, or it is crazy expensive like a $28 5/16-18 x 1.25 bolt, that I can use Grade 5 hardware? Thanks again! Phil
 
McMaster.com (Search for Mil Spec bolts.) I just had the same issue getting bolts for my O235C1B.
 
beware of counterfits

There is lots of folklore about poor quality fasteners shipped from overseas that are marked as grade 5 or grade 8. I don't really know whether to worry about it or not. I have never had a problem, never found a soft bolt at my local hardware store. But I think it does warrent just a bit of scrutiny -- a place like NAPA is probably pretty safe to have real qualiy stuff.
 
scsmith said:
There is lots of folklore about poor quality fasteners shipped from overseas that are marked as grade 5 or grade 8. I don't really know whether to worry about it or not. I have never had a problem, never found a soft bolt at my local hardware store. But I think it does warrent just a bit of scrutiny -- a place like NAPA is probably pretty safe to have real qualiy stuff.
Click to expand...

Probably okay, but you'd never know because you have no pedigree on the fasteners. I don't know if it's even a concern for these applications, although it might well be.

Even if you *have* the paperwork, that's still no guarantee...there was quite recently a giant mess (and federal criminal charges levied) with titanium from a certain company, where the data was out-and-out faked, and the material was found to fail at less than half the specified values for stress. Caused all sorts of grief and analysis and rework on our vehicles.

Probably the best you could do is, as noted here, buy from reputable outfits and keep your ear to the ground for info about bogus parts, and then keep a watchful eye during inspections for failed fasteners.
 
I needed an odd length for my case mount alternator bracket, and most of the local sources like Tractor Supply and Ace only carried 1/2" length increments. We are fortunate to have a local fastener specialist who had 1/4" length increments in stock. You might look in the phone book or google maps to see if you have a similar source available.
 
Industrial hardware

jaredyates said:
I needed an odd length for my case mount alternator bracket, and most of the local sources like Tractor Supply and Ace only carried 1/2" length increments. We are fortunate to have a local fastener specialist who had 1/4" length increments in stock. You might look in the phone book or google maps to see if you have a similar source available.
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Good advice. Frequently listed under something like "industrial supplies" a bolt shop can be a real resource. I recently needed a fairly long metric bolt for a car project. I gave the dimensions to the lad at the counter. His response was "Plated or black oxide, hex or socket head?" Try that at Home Depot. :rolleyes:

John Clark ATP, CFI
FAA FAAST Team Member
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
Buyer beware...

FYI. Don't think that NAPA or even Aircraft Spruce never gets a few bogus parts that slip by them...

The Aircraft Safety Act of 2000

The title of the Aircraft Safety Act (the Act) reflects the primary
purpose of the bill: to safeguard passengers and crewmembers from
the dangers posed by installation of nonconforming, defective, and
counterfeit parts in civil, public, or military aircraft or spacecraft.
The problems associated with nonconforming, defective, and
counterfeit aircraft parts are legion since a single domestic passenger
airplane alone can contain as many as 6 million parts. Industry has
estimated that as much as $2 billion in unapproved parts are now
sitting on the shelves of parts distributors, airlines, and repair
stations. Over the past few years, the Department of Transportation
Inspector General and the Federal Bureau of Investigation have
obtained 136 indictments, 98 convictions, nearly $50 million in
criminal fines, restitutions, and recoveries in cases involving
unapproved aircraft parts. Additional investigations are underway
with no sign of abatement. Yet, until now, no single Federal law
targeted the problem in a systematic, organized manner. The Aircraft
Safety Act of 2000 has changed that. The Act employs a four-tier sentencing approach. Asimple violation of the Act carries with it a maximum punishment of 10 years imprisonment and a fine of up to $250,000. If the offense relates to the "aviation quality" of a part and the part is installed in
an aircraft or spacecraft, the maximum punishment increases to 15
years and a fine of up to $500,000. If, however, the part to which the
offense is related fails to operate as represented and causes a
malfunction or failure that results in serious bodily injury, then the
maximum punishment rises to 20 years and a $1 million fine. Finally,
if the part to which the offense is related fails to operate as
represented and causes a malfunction or failure that results in death,
then the maximum punishment increases to life imprisonment and a
$1 million fine. Fines for corporate offenders can be as high as $20
million.
 
Commercial Hardware sourcing.

I would not buy any commercial fasteners that have a critical purposes from these type of business's.

A) Big box stores that do not do their purchasing at their local facility, as it seems that most of them have no idea what country they are made in, and I would not trust the sticker on the little plastic bin box that have been co-mingled.

B) Bolts 1/4" dia that have Head Markings that are not recognizable or absent.

C) Things that look questionable, its not worth the risk.

There are hundred of good distributors of commercial fasteners in every state. They should have traceability and certs on file.

The Manufacturers are required to meet the applicable parts of the fastener quality act. The link has the word metrics but it also applies to US fractional fasteners, Grade 5 and above.

http://www.nist.gov/pml/wmd/metric/upload/fqaregs2.pdf

You should be able to get the Lot# on a certificate of conformance from the legitimate distributor.

Caveat.... When they ask you what it's going on and you tell them its for a plane, they may be hesitant to deal with you.

Tell them that it is not a critical part,( it should not be ) you just need to ascertain it is made to the standard to which it is head marked.

On a steel Fastener no marks= Grade II (soft junk, stay away)

This should help.

As a comparison, regular AN bolts have a tensile strength of 125 ksi.

NAS series bolts http://www.gen-aircraft-hardware.com/images/pdf/nashhb.pdf NAS bolt have a tensile strength of 160 to180 ksi.


http://www.tessco.com/yts/customerservice/techsupport/whitepapers/pdf/bolt_grade.pdf

Remember YOU are the manufacturer of the Aircraft and responsible for its airworthiness.

I hope this clears a few things up, sorry it may still take time for you to procure for your individual requirements.:eek:
 
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