So I'm finishing up the parts to do a brake swap (mmm, zo6's). And I'm defiantely going to be using loctite but hearing briefly about safety wiring awhile back that piqued my interest. How does this work? How do you detirmine the wire size, bolt hole size, routing, etc.

I just want to take some more precautions when slapping this stuff together. TIA

 

Basically it's just some wire run through a hole in the bolt and secured so that the bolt can't back itself out. Best choice for wire is some stainless so it won't rust.

Drill a hole through the head of the bolt big enough for the wire to run through. The thickness of the wire doesn't have to be big but you want it thick enough that it takes some effort to break. 18 gauge wire is enough. Loop the wire through the hole then twist the 2 ends. Normally you connect at least 2 bolts together so one will anchor the other. The wire comes off the head of the bolt so that it tightens if the bolt tries to unscrew.

If loctited and properly torqued there's little need for lock wire. It's not like you're in an aircraft. About the only thing commonly safety wired is header bolts but I've never lost one myself. My Harley could use a few things wired some day.

 

Proper safety wire is actually annealed stainless wire, so it’s softer and you can twist it more without breaking it. You should be able to get it at a speed shop (moroso makes some) or I’ve gotten small spools of it at sears before

 

My opinion too.

JamesC

 

So how would I know what I should torque these adapter brackets too?

 

All bolt sizes have a generic bolt spec ie: 3/8 NC bolts ware torqued to 35-42 lb/ft. Just do a web search for a bolt torque spec sheet.

 

do a web search on aviation saftey wire. .32 is the standard size. we satey wire every bolt on aircraft.

 

Every bolt? How about that three-wide row of cap screws on the wing root of a DC-3/C47? There isn't even room for wire there, let alone a wrench.

Yeah, I know what you mean...

 

The proper torque will depend on the alloy, grade...

 

I prefer safety-wire over Loctite, although there are practical limitations, and the specific application and accessibility will dictate which solution you use. I also have Loctite (red & blue) on my shelf: choose the right solution for the right problem.

use a 1/16" drill in the bolt head, whether allen head or hex head. they sell a little jig that really makes this PITA-task a whole lot simpler. use plenty of cutting oil while drilling the holes, drill press is mandatory. have a few spare 1/16" drill bits handy (I prefer the titanium nitride ones). This is one time where you'll really notice that the drill bit quality makes a big difference.

if you're drilling allen-head bolts, each head requires 4 drilled holes, 90* apart. if you're drilling hex heads, 2 drilled holes, 90* apart, intersecting.

I've found that ARP bolts are impossible to drill for safety wire since they're so well hardened (a sign of their good quality). But on the other hand, ARP does sell some very handy SS 3/8-16 bolts already drilled for safety wire that are better than any Gr.8 bolts. Those come in very handy for headers.

also, it's worth it to have a 1/16" punch laying around, for those inevitable instances where the drill bit breaks off right as it breaks through.

I use safety wire on my header bolts (lost too many of them on my daily drivers, regardless of what folks say, tightening and retightening etc). I also prefer to safety wire anything that's "life-safety" related, like steering & brakes, driveshaft & half-shaft U-joint straps, suspension, trans mount, stuff exposed to vibration and heat-cycling. also bolts that go into aluminum where heavy-duty torquing will usually result in stripped threads (like alternators).

Safety-wire flat-out works guaranteed. the basic wire size is .032" that works for 99% of the applications. although they also sell some industry-standard jumbo-sized .041" and some flyweight .025" stuff.

you'll need the special pliers. There's the expensive US pliers that are outstanding, or you can take your chances with the made-in-china stuff that probably costs 1/10 as much and works pretty good most of the time, but noticably not-as-well as the American-made MIL-BAR pliers. I have both, and use both. If you're only going to get one pliers, get the shorter ones (engine compartments are not very spacious).

always make sure you have the wire "pull" going in the right direction so that it tightens the bolt, not pulling in the loosening direction.

there's a couple of reference books on the subject. it is a tedious process, painstaking, lotta swearing involved, time consuming, etc. But... I've never regretted safety-wiring a particular bolt. peace of mind.

 

All good information. However, don't confuse a hard part with quality. A truly high quality fastener will have excellent shear and tensile properties without requiring a high Rc hardness. Excessive heat treat can create hydrogen embrittlement. That is usually done to meet test specifications with an inferior quality material, whereas a high quality fastener can meet test specs with a better alloy at a lower hardness.

Neither one would be a real treat to drill for safety wire, however.

 

I was biting my tongue on the subject, but I might as well chime in:
I was going to use safety wire on my headers, drilled my allen capscrews for it and everything. I got some safety wire from a shop that had no idea about the stuff, so it's .041" and hard as hell to work with. I gave up. Headers are tight in there! Maybe i'll try it again with a suspension part or something... And using .025" stuff.

 

Here's an example picture of what Stephen was talking about. I bought my 9-inch differential from a race shop and it came with the ring gear bolts safety-wired. They are wired to each other in pairs.

 

Sonix:
for headers, use the .032 wire size. you'll make the job a lot easier if you use the predrilled ARP SS hex-head bolts. for small-blocks, it's better to use the 7/8" long BBC pre-drilled ARP header bolts 400-1104, they provide sufficient thread engagement. the black oxide-coated allen-head bolts I've used in the past always rust after a while, unless you paint them with hi-temp engine enamel. you'll certainly need the shorter safety-wire pliers. a pair of those really long "stork" long-nose pliers helps. it's definitely a whole-day job.

 

Safety Wire? You mean Lock-wire. There are a TON of lock-wire sizes, depending on what you want to do. If you are going to do it, GET THE LOCKWIRE PLIERS. Not twisting the wire between the bolts almost defeats the purpose of putting it on. Remember this, 7 twists per inch.

 

I'm positive you can buy aviation grade bolts with the safety-wire holes casted into them, there are two types of safety wire holes made... an X through the middle or it can just be ran through a corner. After working on B-1B Bombers for six years, I think safety wire on autos is a bit ridiculous unless you have some serious tension or a few thousand psi behind the bolt. In aviation it is primarily used due to very high vibrations (turbulence or Mach 1 air flow, etc) that an F-body would never experience. At best, I'd kotter key my lug nuts.

 

the "X" practice is wrong

 

Care to elaborate? It has been practiced by the US Air Force for at least the past 30 years. Also, twists per inch depends on the size of safety wire being used, generally the smaller the safety wire the more twists per inch required.

 

LOCKWIRE

 

sometimes, a little bit of overkill provides the desired guaranteed solution to a problem.

the big-motor endurance road-race folks seem to be firm believers, although perhaps it's sometimes required by the sanctioning bodies.

 

Been through many inspections on a SSBN where I recieved hits on my lockwire for it being of the "x" pattern through a bolt. It has something to do with the greater possibility of weakening the lockwire when you pull it back through. Its been practiced in the USN for as long, if not longer.

 

Using safety wire and tie wire is like doing drugs. Its a cheap, easy fix and if you use it moderately may be ok, but dont get carried away and use it all the time!!!

I know in certain situations its a correct solution to the problem such as this one, but be dont get carried away or your whole car will be held together with the stuff!
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Ok that post made sense in my head but now that i read it i realize it isnt pertinent to the discussion at hand. My bad

Speaking of drugs.....