Wrench tips
Tip #4: Sort Your Bolt Bucket
Bolts shall not be thrown away. This mandate is programmed into every car guy's DNA. Sadly, most car guys still practice a Neanderthal strain of bolt preservation that involves keeping them all in a giant bucket. This simply will not stand. If you ever actually need a bolt from that bucket, you'll waste an embarassing amount of time looking for the right bolt and will probably settle for one that doens't fit properly anyway.
Proper sorting means first understanding how bolts are sized. The size wrench you use on them has nothing to do with the size. The bolt you use a 10mm socket on is not a 10mm bolt. It's probably (but not always) a 6mm x 1.0 bolt. 6mm is the diameter of the bolt shaft, 1.0 is the thread pitch, or how many mm the bolt will move for each each turn of the threads.
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| The self-aligning nipple bolt (above) was designed for quick factory assembly. The unthreaded tip aligns the bolt to minimize the chance of cross-threading when the bolt is installed quickly with air tools. These are great to use in blind holds where you can't easily see if you've got things lined up. The angry sawtooth grounding bolt (below) has a sawtooth pattern that serves a bit of a self-locking function, but mostly ensures good electrical contact between bolt and hole, even on painted holes. These are usually used on any factory grounding point. | ||
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Anything I work on consists 98% of the following sizes: M6x1.0, M8x1.25, M8x1.5, M10x1.25 and M10x1.5, so most of my sorting can be done with just 5 little buckets. I'm a little OCD when it comes to bolts, though, so I have additional buckets for oddball stuf like screws and washers, interior fasteners, and the 7/16-20 bolts that are the international standard for seat belts. Then there are the travel bins for bringing bolts to races, the imperial hardware… its a disease.
Now that you have a big bucket full of bolts, sorting it will be a pain in the ass. This is your punishmet for putting them in that bucket in the first place. Drop $1.99 on a Harbor Freight nut and bolt gauge. Once you have your bucket sorted you won't need this any more (the bolts you've already sorted can be used as gauges) but the gauge will be handy for helping you dispose of all the silly imperial bolts hiding in your bucket.
Once your bucket is sorted, life will get much easier. Tossing each new bolt into the correct bucket is no harder than throwing it into the giant co-mingled box of confusion you're using now.
When you're digging something, say an M6 x 1.0 bolt, in a bucket full of drywall screws and rusty 1/4-20 lag bolts, just finding something that will thread in a few turns is a triumph. If you're only digging though a bucket of M6 x 1.0 bolts, though, you can dig for the gems, like the sel-aligning nipple bolt and angry sawtooth grounding bolt on the right. You can actually dig up exactly the right length, head style, captured washer or finish. Both the speed and the quality of your work will improve dramatically.
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| Once your bolts are sorted, figuring out what goes where is easy. If you know everything you're dealing with is metric, you can probably eyeball it. If not, try meshing the threads with a known bolt. The top photo shows how to distinguish similar, but incompatible bolts like the M10 x.1.5 on the right, and the 3/8-20 on the left. Always be sure to mesh as many threads as possible. These bolts appear to match if you only mesh 3-4 threads. A correct fit will look like the bottom photo. |
-Dave Coleman
Got any tips of your own? email them to dave@motoiq.com!
