Drill rod grade/temper?

[stealthshooter]

I'm looking to buy some drill rods to make punches out of and I was wondering what grade/temper would be best? In the 9/32" I'm looking at they offer,Grade A2 Multipurpose Air-Hardened Tool Steel,Grade M2/M7 High-Speed Tool Steel,Grade M42 Cobalt Tool Steel,Grade O-1 Oil-Hardening Tool Steel,Grade W-1 Water-Hardening Tool Steel

The grade I was wanting they don't offer in 9/32" which was,Shock-Resistant
Air-Hardened S7 Tool Steel.......So which would be the next best choice?

Thanks much!

[blaser.306]

Whatever type you use be certain to leave the punch softer than the die! One minute of carelessness may cost you the time and incovenience of having to turn a new one, But that is much better than wrecking a polished die surface. Just my thoughts on the matter.

[OneShotNeeded]

I absolutely agree with blaster.

On the other side I made a de-rim die and used HSS drill rod. Also made a punch for point forming 22 jackets and used 5.56HSS drill rod. So far no problems but tolerances are tight.

Keep looking on here alot of people use different things. If you do go with drill rod McMaster Carr has a huge line of pieces and parts alot of us have used in out "die making attempts."
Good luck and have fun.

[Reload3006]

personally I like A2 because its easier for me to harden because its air hardening but there are lots of considerations as everyone else has mentioned.

[GRUMPA]

Personally I would go with what-ever you can work with within your budget. And after you get things whittled down to what you actually want I would go from there. Some of that stuff is dang hard to work with.

We used to make something out of softer materials to work out the kinks and then if there was any sort of tooling, would go with a tool steel like O-1 or D-2 for the long running jobs. But last I knew when I left the machining industry O-1 and D-2 were $100LB, and in most instances heat treat 4140 worked just as well.

[Reload3006]

Personally I would go with what-ever you can work with within your budget. And after you get things whittled down to what you actually want I would go from there. Some of that stuff is dang hard to work with.

We used to make something out of softer materials to work out the kinks and then if it was any sort of tooling, would go with a tool steel like O-1 or D-2 for the long running jobs. But last I knew when I left the machining industry O-1 and D-2 were $100LB, and in most instances heat treat 4140 worked just as well.

before I read your post i was thinking why not pre - hard 4130 or 4140

[JIMinPHX]

I normally hear O-1 & W-1 called drill rod. I sometimes hear A-2 called drill rod, but not usually. The other grades that you spoke of are tool steels, but not "drill rod".

If your application is not particularly demanding, then I'd just get a piece of el-cheapo W-1 or O-1 & use it without any hardening. If you need to punch really tough materials, then we need to dig a little deeper.

If you grind a transverse radius on the sharp cutting tip, then you will need a lot less force to operate the punch. Flat cutting tips try to cut the entire slug at once. Cylindrically concave cutting tips start with two points & then move along the circumference, cutting a little at a time.

[deltaenterprizes]

I use grade 8 bolts, similar to 4140 and Tractor Supply sells them by the pound.

[BLASTER62]

I use bucket teeth retainer pins for excavator buckets, once you get past the case hardning they cut nice.

[stealthshooter]

All of those I listed are from Mcmaster here is the link and they are all pretty reasonably priced. http://www.mcmaster.com/#steel-drill-blanks/=f4y4fl

[Reload3006]

I don't know what the extent of your machine shop experience is. So if I seem to be too juvenile please forgive me. I do not mean any offense. When using drill rod O-1 and A2 especially if you cut this with a friction saw(suicide saw) or get it especially hot it will immediately turn brittle. and will need to be tempered. or you will not get the results your hoping for. In a like manner if you are trying to use something that is case hardened once you cut past the outer layer approximately .025 in in radius .050 diameter your in soft metal again. If you get pre-hard 4130 4140 4350 and as your working it if it turns blue you have already drawn back the temper of it and started making it soft again. if you grind it and it turns red you have completely annealed it. So be careful when your working your metal or you will be spending a lot of time and money on nothing.
You definitely want to stay away from the M2/M7 High-speed tool steels because they are made for cutting tools drill bits reamers lathe tools. they are either brittle hard or soft there really isn't any in between. for swaging punches dies you need about a 48 - 52 Rockwell C hardness that will make your punches and dies hard and tough but not brittle. a file is around 58 - 64 Rockwell c ... just for comparison

[martin]

Gang,

About a year ago, I Eamiled Corbin asked what they uses for punch material and recieved the following information:

They suggested "using 41L40 heat treated to 1550 degrees and oil quenched. After it is cool, clean up the punch and temper it to 400 or 425 degrees for an hour. This will give a punch that is not brittle and will wear well."

I can say from my experience that 41L40 is a lot easier to machine and works well for my punches.

Martin

Martin

[scrapcan]

Martin,

thanks for the info.

[JIMinPHX]

41L40 is the easy machining little-brother of the more common 4140 chrome molly steel. It's nice stuff, but you don't find it at every corner hardware store & it ain't as cheap as the drill rod alloys are. It also case hardens very well.

You can download a general purpose heat treating guide from the McMaster Carr website. It should cover most of the tool steel alloys that they sell. http://www.mcmaster.com/#=f72ilu I don't see heat treat info for the chrome moly family in there though. What Martin posted about quench after 1550, then 400 for an hour sounds about right, going from memory.

[stealthshooter]

I can't find the 41L40 in 9/32". Do any of you know where I could find it?

Thanks much!

[Reload3006]

do you have a local metal supplier. I would imagine you will have to order it. I have to ask though do you have heat treating facilities? if you don't your going to be disappointed with what you get. there is a lot more to getting proper temper in metal than just heating it up with a torch and quenching it. there is controlled atmosphere soak time and quench medium. take a trip to your local library and read up on heat treatment of metals. I would suggest for you to get what your wanting buy prehardened 4140 4130 at about 45 RC scale tough machinable. not brittle.
I know once again advise you didn't ask for I mean no offense just trying to save you money in the long run.

[stealthshooter]

Yes I have heat treated my home made knife blanks. I have a nice machinist pocket book that explains everything you would ever want to know about it. I don't have a local source for it.

[Reload3006]

Yes I have heat treated my home made knife blanks. I have a nice machinist pocket book that explains everything you would ever want to know about it. I don't have a local source for it.

then I am curious why your asking all the questions when you seem to already have all the answers?

[stealthshooter]

I never asked. About heat treatment. I asked what material is best for a punch. I'm not afraid to admit the things I don't know.....such as the best material for a punch.?

[Reload3006]

I am coming to you with 30+ years experience in the Aerospace Machine shop/Tool N Die fields. I also hold a Bachelors of Science in Mechanical engineering. I do know what I am talking about in this regard. I also know what i don't know every thing about there are always tips and tricks that we can learn from one another. This is why in a different thread I posted that I was having trouble with my copper tubing jackets. That is why I went and talked to a metallurgist at Boeing because I know he knows what I don't. Suffice it to say from your post I know a considerable amount more than you about metal and heat treating. Just because Corbin uses 41l40 doesn't mean that its the best option for you by the way CH4D uses 12L14 and case hardens his dies I talked to Dave my self at CH4D. I personally don't think that is a very good option for dies. But its easy to machine and can be somewhat hardened. that is why when you over pressure a CH4D die it will bulge or the punches will bulge (they are case hardened) Corbin dies will break because they are heat Treated 41L40 (L stands for Lead) We call those steels Lead Alloy in the industry. They machine about as easy as brass but they bring problems to the table as well. Unless you have an Atmospheric controlled heat treating furnace 41L40 will not do what you are wanting to get done. Maybe you will harden it Maybe you wont Maybe you will anneal it Maybe you wont. Maybe you will be able to temper it Maybe you won't but you you will pay out the nose for it and Possibly get what you want. and Judging from the pictures you posted of your drill press Lathe set up you have going its not going to matter too much what steel you use a dremmel for a cutting tool will get the shape you are looking for but you will loose any temper you may happen to have. If that is the way you intend to go about making your punches then by all means Knock your self out. In this thread you were given a link to Speedy metals , Grainger , Roto Metals there are lots of places to buy anything you want its your Money spend it.
I do applaud your ingenuity in getting done what you are trying to achieve living proof where there is a will there is a way. honestly if you dont over pressure you punches and dies plane ole inexpensive 1214 will make serviceable punches and dies they just won't wear well.