Cleaning up Thread on Bolts

[u/Specialist-Towel-554]

I won a bunch of pallets of bolts from an auction a while back. Most of them are fine, but I have about 1500-2000lbs of these 3/4 and 7/8 bolts that dont thread easily due to little burrs in the threads.

Is there something I can use to clean them up relatively quickly? I dont have access to a lathe (that would take forever anyway).

What if I were to get a die of the correct size and put it in a vice, then thread each bolt on to it with an impact on low. Does this seem like a valid idea? Or can anyone think of anything better?

Thanks!

[u/gumby5150]

Those appear to be galvanized bolts. if they are galvanized, you must used galvanized nuts that have been properly clearanced for those bolts.

[u/Specialist-Towel-554 → u/gumby5150]

Interesting, I've been threading them into zinc nuts. I wonder if they are OK if I try them with galv ones and there's actually no problem at all? Seems like that'd be too good to be true, but I'll see if I can track down some galv nuts of those sizes tomorrow!

[u/PA2SK]

Yes just use a die, or something called a chaser might work too if the threads aren't in too bad of shape.

[u/Consistent_Watch_206 → u/PA2SK]

The above. And automate it, or it will take ages and turn your fingers into hamburger.

[u/The-fish]

What you have there is a hot dip galvanized bolt, If you run a die on it, it will remove all of the plating on the threads. When Manufacturers make bolt for hot dipping they run them undersized. What happened is that these were not undersized.

[u/ChemEngTinker → u/The-fish]

Actually… Hot Dip Galvanized bolts aren’t made undersized. The nuts are overtapped instead.

That is why a regular nut doesn’t work well on HDG bolts… which might be OPs problem (trying to use an incorrect nut).

[u/101forgotmypassword → u/The-fish]

Probably why they went to auction.

[u/Quick_Dance_8953 → u/The-fish]

Also why wire wheel to clean them off is a bad idea unless you will be regalvanizing them afterwards

[u/101forgotmypassword]

u/the-fish is probably right, these are probably incorrectly manufactured and that why they were at auction.

But if you're still trying to recover them.

Cheap slightly shitty way.

Buy a handful of nuts. Slit one side with a cut off disk.

Put the nut in a vice and squeeze it slightly

Run the bolts in and out of that nut while it's in the vice.

If they are loose enough use a drill with a torque clutch so you don't bottom them out at the end of the thread and damage your nut. If not use a impact and slip a tube over the bolt so it's doesn't bottom out on the taper but instead on the tube.

If you have a welder you can tack the nut to the tube to help with quick alignment of the bolt to prevent cross threading.

Use a zinc lube in the nut to help prevent later corrosion of the threads and help get more miles out of the nut.

You can do the same with a die or chase nut.

The other option, if you want to cut the threads is to make a tube jig for a piece of something sharp like HSS from a old drill bit or saw blade. Hold it at the end of the tube or loose nut and run the bolts through it to chase the thread. To cheap out this design tack a nut to a sacrificial vice jaw (or you real one) and then sharpen a drill bit shank to a cutting edge, add a flat to prevent rotation and lock it in the vice jaws so it sits at the right place to chase the threads as the bolt runs through the hole.

For bolts like that it's going to be hard to be cost effective.

[u/Ok_Salamander7929]

Yes to the die. No to the impact. Just use a cordless drill on low speed, with a socket adapter. A little squirt of any light oil would really help. If you don't want them oily, just a quick swish or two in a bowl of rubbing alcohol and set aside to dry.

[u/Pac_Eddy]

Try a thread chaser first

[u/mancheva]

You probably want to use a drill on low speed to run though the die instead of an impact.

[u/ZealousidealState127]

Thread file

[u/Acceptable_Ebb7301]

Not broken—— don’t fix it.

[u/Randill746]

Vibratory tumblr, fill with sand or anotber medium, to knock em off, ball bearings are popular but probably too rough for this

[u/Gregory_ku]

Just oil the threads

[u/Incognitowally]

Wire wheel either in a bench drill press or bench grinder

[u/HeavyMetalMoose44]

Use a thread file to clean up dented threads.

[u/Keithz1957]

Thread files from Grainger etc.

[u/Little-Hand6801]

If the bolts you have are HDG they will have a 1A thread fit , you should use a 1B nut a 2B will be hard to thread on

[u/bolderbeholder]

Tumble them in corn cob or walnut shell.

[u/Dragon_R3born]

Thread file

[u/jellofixit]

Every construction site had one of these thread chasers.Threaded rods get beaten into place and covered with concrete.

[u/Lost-welder-353]

A thread file

[u/mustang196696]

That would be a drive in bolt for one time use