easy way to shorten a screw or a bolt without having to re-die the threads...

i never have the right length screws or bolts and am always needing to shorten them. here is a
trick. place the length to be cut off in the vise so you don't mangle the threads of the piece you
want. Make sure you have placed a wingnut or nut of some description on the end you wish to
keep. Later you wind this off to clean up the threads so you don't need to re-die the screwthread.

Step 1: Place Nut or Bolt on Threads.

a wing nut is good, any nut will do. this will effectively by your die for cleaning up the threads.

Step 2: Mark Cut and Place in Vise.

i have marked the screw (green marker) with the cut off length and am holding it in the vise on the section of thread that is to be discarded.

Step 3: Hack Saw Off.

hack saw is fast and effective for small diameter screws and bolts. you might need a cut-off wheel
or dremel for hard steels and larger diameters.

When you are finished wind the nut off and in that process the thread will be fixed by the nut as it
comes off. It wont be perfect but it will prevent cross threading and make starting the thread a lot
I needed a whole bunch of 7/16 inch hex cap screws cut down so I rigged up a 7/16 socket in my drill press to chamfer the end once I had cut them to length. I placed a magnet then a hex nut in the socket to hold each cap screw while chamfering the end with a file. (I needed the nut to keep the magnet from pulling out when screws were removed) If the socket is deep enough, the nut that should have been used while cutting the screw to length can be left on for added stability of the screw as it spins in the drill press within the socket.
<p>well anything up to 8/32 I use a stripper/bolt cutter, bigger I put on two nuts and hack saw them off. A dremel is nice, but as I did all of this on job sites the most I ever had was nuts/threaded rod connectors (giant nut). Obviously a vice is nice, but often I held the nut with vice grips and used a bolt cutter or hack saw or sawzal. I could do 1/4 threaded rod by hand using Kleins, but too much clean up is needed on threads. The way shown here is best if you have no dremel/other power tools. </p><p>Another help is to wrap a few inches of electrical tape over the place you want to cut. That kinda does whatt a dimple does when you drill a hole in something. Give the cutting edge firm purchase in 2 spot, and usually will not wander, well with practice anyway. </p>
<p>Shirt sweet and to the point. How about turning the wing nut around and using the flat base as a guide for the saw? I should think a straighter cut AND easy deburring could result.</p>
if its small enough some wirestrippers also have small bolt cutters built into them
cool i did this in reverse and got a longer bolt =P<br/>
My son saw me doing this one day - my vice was broken (don't ask!) and I was using a pair of pliers to hold the bolt. He came up with the ultimate slap-head "doh!" moment when he suggested I put the bolt into my drill chuck instead.... works great especially if you're 'onsite' and don't have a vice handy but do have a drill
You might even be able to cut it by just spinning the drill and holding the saw steady. Also, thanks for the tip--I was trying to do this today, but holding the bolt with my feet didn't really work. I stripped it and now I have to get new ones. :(
lol, i did that today while making myself a pocket PVC hacksaw (from another instructable)
I've used a jigsaw with a metal cutting blade to shorten bolts with success before - much quicker than hand-sawing. Remember the vice/workbench and goggles though or you might lose an extremity or two.
You could use electricians pliers for smaller screws, but this method works on larger stuff as well. FWIW, this is exactly how my dad taught me to do it back in the 70's. A quick buff on a wire wheel on your benchtop grinder cleans the pointy bits up nicely as well.
Or use a dremel.
You can also invest in a pair of electrician's pliers for handling smaller bolts- they have threaded holes through both parts of the jaws. You open the jaws, thread the bolt through, and then close the jaws again. Then, you unscrew the short bolt from the handles, and you're done! No matter how you shorten the bolt, though, make sure you deburr the end- nothing is worse than wrecking good threads... talk about a headache!
Jeff, I like your miterbox idea. I'll have to try it. What I like to do is take two nuts, screw them to the "keeper" side, and tighten them together so that their flats match. Then use the nuts in the vice to hold the bolt.
If you use *two* regular nuts (I guess you could use wing nuts if you face the wings out) and center them where you want to cut the bolt with just enough space between them to put the hacksaw blade, you will find it easier to get a straight cut across the threads. They act like a mini-miter box.<br/><br/>And to get a *really* nicely finished end (useful if you are going to be doing/undoing the bolt much), chamfer the end after you cut the bolt (a few swipes of a file or a couple seconds at the grinding wheel) and then unscrew the remaining nut. There will be just a slight burr left that you can file/sand off - and then the end of the bolt will be as good as factory finished. <br/>

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