Drill rod question

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V 45

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A friend gave me some drill rod. How do you tell if it's oil harding? Some has red paint on the ends and some are white. How do you temper if not oil rod?
Thanks again
 
If I did not see an O1 on it or a W1 I would guess it is oil hardening, if it is drill rod and did not harden try to quenching it is water. Mike
 
Hi,

Are you going to heat treat it? If not, it really doesn't matter very much. Just use a cutting speed of 80-90SFM and be happy.

If you do wish to heat treat it, either water or oil will work for either. Just not as good as the proper medium should. The thing to remember is that water is a more severe quench than oil. It could cause cracking in O-1. And oil quench may not bring W-1 to full hardness.

To draw either, 400F oven for a couple hours works for me. These are pretty simple tool steels so not much reason to make it harder, (pun intended), than needed.


Once hardened, there really isn't anything to choose from. But if used annealed, I prefer O-1 because I think it wears better. Which maybe all in my head.

Dalee
 
Thanks for the replies. I have both I think. I haven't tried hardening or annealling yet. But wanted to make some D bits .
 
One of these days I am going to have to do more study on heat treating of drill rod. I have seen everything from elaborate sequences to heat to carrot color, quench, polish, heat to straw. The latter is mostly what I have done for the temporary tools I have done with good luck. I have not tried the oven annealing partly because my wife would not take kindly to me using her oven.
 
The tempering is all most same for both
I have found the color will be the same for all MFG
Just try oil if does not get hard then try water note use salt in the water (brine)

Note a torch is safer for tempering than using the wife's oven :hDe:, just grind a spot and look for the color of the metal of find a toaster over will work too.

Dave

A friend gave me some drill rod. How do you tell if it's oil harding? Some has red paint on the ends and some are white. How do you temper if not oil rod?
Thanks again
 
I think there is some information here but little knowledge , if the experienced model makers can suffer it perhaps this might help new-comers .
Carbon tool steels are hardened by heating to bright red/orange then rapidly cooling.
At orange heat the structure of the steel is known as martensite which put very simply is a hard crystaline structure.
If the steel is rapidly cooled then this structure is fixed and prevented from returning to the softer autensite structure.
It is the speed of cooling rather than the media that is important.
Smithdoor says use salt in the water but not why , the answer is that brine has a lower freezing point than plain water so it can be used colder ie. quicker cooling.
Oil has a slower cooling effect than water , this can be important in complex shape tools as cracking can occur due to stresses set up by very rapid cooling.
It follows that the method and media for quenching have more to do with the tool than the steel.
As a general rule a part to be hardened should be brought up to temperature and soaked for 1 hour per inch of section to ensure even hardness throughout.
Quenching should be as vertical as possible and the medium should be of sufficient volume and well agitated/ stirred to dissipate the heat quickly.
After hardening the steel will be glass hard .................test it with a file , the file just skates across !
Hard as glass but as brittle too , and liable to chip or even snap,
If the tool is liable to shock , as in a milling cutter or lathe tool or a screwdriver , a chisel or perhaps a spring then some of the brittleness must be removed .
This is the tempering side of heat treatment.
You can find much to explain this using a web search.
 
Hi,

A good post by Abby as how the different quench media works.Thm:

Smithdoor, an excellent shop safety tip! ;D I should have clarified my tempering oven statement, as SWMBO can be a sticker about ovens. I use an old toaster oven I picked up at a garage sale as my tempering oven. And we have regained marital bliss once again.:)

A small selection of drillrod/silver steel is a very handy thing to have some days.

Dalee
 
Great post Abby. I did a blacksmithing course many years ago and things were explained the same way. Most of which i have forgotten over the years.
 

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