• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Threading a Steel Rod

toxcrusadr

toxcrusadr

Omelette au Fromage
Subscriber
Not exactly a vehicle related question but I know you guys know your stuff here.

Got a piece of 1/2" steel rod I want to put threads onto for an inch or two at one end. I have a 1/2" die and a holder for it but I've never tried to thread anything this big. I can't seem to get it to bite in to get it started. I even ground off some metal at the end of the rod to make it a little tapered. Is 1/2" just too big to do by hand? Or do you actually need a smaller rod blank to make 1/2" threads?

I could use a piece of threaded rod but it's for a stand for lab glassware (sort of a, uh, distillation apparatus so to speak :smoke:) and I'd much rather have smooth rod with just a couple inches of threads at the end to secure it to a base.
 
Register to hide this ad
For some reason it's easy to find charts of drill sizes for taps, but not for rod blank sizes for dies.
 
A 1/2" bolt thread is actually a little smaller than 1/2". But not by much, about .008". You should be able to get the die started. The die has a taper to it, make sure you start on the big side.
It could be you have a hardened steel rod or maybe tool steel. They will be extremely difficult to thread if not impossible. If it files easily it should thread OK.
 
Your 1/2inch rod is probably larger then 1/2inch by a few thousands and should be under as grillebilly said. Also, good lube is a must.(thread cutting oil)
 
whats the rod made of? Some materials are too hard to cut by hand with a die. If its just common hardware store round rod, that cuts pretty easy, if its hard its not going to cut. A file will tell you, if the file cuts it will thread with a die, if it skates off it will not die cut.

Also if its oversize you're not gonna have much luck with it. Cheap dies also will give you trouble. I do most of my thread cutting with plain old pipe cutting oil mostly because its inexpensive and you can get it anywhere.
 
Try tapering it a lot, you can always blunt it later. You will probably have to push pretty hard at first to get it started.
 
grillebilly said:
It could be you have a hardened steel rod or maybe tool steel. They will be extremely difficult to thread if not impossible. If it files easily it should thread OK.
Click to expand...

Definitely try the file test. If the file refuses to bite and slides off, it's hardened steel like drill rod. Without annealing it will not thread.
 
...and based on the replies above I now know if I get stuck on a metalworking problem I will likely get a good answer here.

hugs_drib_cindysuen.gif
 
Getting the die started is the most critical step.

As stated above, be sure your rod is chamfered and your die has the bigger tapered side starting on the rod.

Hold the die handle at the extreme ends and go only 1/4 turn, making sure that you are square. Then go another 1/4 turn, ensuring you are still square.

Once you've gone 1 - 1 1/2 rotations and you are still square, you will be good to go from there.

And use plenty of lube!
 
Thanks for all the advice guys. I'll try a file on it first, who knows it could be the hardened stuff.

If that's not the problem I'll try tapering it more on the grinder.

I'm definitely using the right end of the die, so I got that going for me. :p

And always, plenty of lube. :naughty:
 
It's part of a home-made lab apparatus. Who knows where the one plain rod actually came from - could be lab supply stuff or could be from a metal supply shop.

Remember the stands in Chemistry lab? A vertical rod in a base that you could attach clamps and rings and such to. Well this one was from a soybean oil processing plant lab, used to distill the solvent off oil extracts to measure the amount of oil. It has two different rods, mounted onto a 3-ft piece of 2x12. One with a round base that's screwed into the wood - clearly from a lab supply house - and the other was just a rod pressed into a hole in the wood - that's the one I want to put threads on. I want to make a new wood base for the whole thing so it can be disassembled for storage, because it's quite cumbersome all assembled. Thought I'd embed a nut or two into the wood and put threads on the rod, and voila, easy disassembly.

I don't want to use threaded rod because you don't get a very good surface to clamp things onto.

BTW I'm not using it to test soybean oil. Theoretically, it would make a highly accurate and precise distiller for refining crude distillates of grape fermentation products (and similar materials). :smoke:
 
You must log in or register to reply here.
Back
Top Bottom