Drilling holes in 1084 steel

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Folsoml

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Jul 15, 2016
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Hey guys! I'm a beginning blacksmith/knife maker. I use a Majestic Forge 2 burner propane forge. I've made a few knives and swords using 1095, 15N20, and damascus made with those two steels. I just started using 1084 steel and I'm encountering a strange problem: I cannot drill through it--even before final hardening. I did not have this problem with the other steels. I'm using a Ryobi drill press and various brands of drill bits rated for steel. The bits will cut in just enough to put a dimple in the steel, and then sit there and squeal loudly. My process is as follows: I will take the steel stock and cut it to size with an angle grinder. I heat it and forge it into the shape I want. I then use my angle grinder with flap discs to smooth it out. I never quench it during this process. I then will fit the handle to the blade and (try to) drill holes in both. It is only after this step that I do the final hardening. Again, this process worked fine with the other steels, but not the 1080.

Does anyone have any thoughts about this?
 
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Hi Folsoml, there was a great thread a while back addressing a similar issue with some of Aldo's 1084. His has vanadium in it which adds an extra variable but I still think this thread is quite relevant to your issue as it has to do exactly with drilling before heat treat and your steel is similar.

Here's the link to the thread:

http://www.bladeforums.com/forums/showthread.php/625932-Will-1084-air-harden

Some great information in there, which I think should be able to set you straight. It appears that Kevin Cashen's method in the post is aimed towards someone using a forge which is perfect for you.

If you do have access to an electric oven you can do a more precise sequence for normalization followed by a spheroidal anneal. If you do have access to that there's a bunch of info about it in the heat treatment sticky.

Good luck with that!
 
Thanks! His description of the problem is exactly the same as mine! So much so that I just double-checked my last order from NJ Steel Baron and it is 1084 that I am using--not 1080.
 
Ah perfect then it's even that very steel from Aldo with the added vanadium :) So it looks like you have a good method laid out for you then, I'm very interested to hear how it works out!

I think the key is going only to a very dull red and not going into the orange ranges when you heat the steel...at least while you're annealing. The normalizing step (first, before the anneal) will be more in the orange range.

While it's not a great reference for your steel temp, a chart like this can at least be a little helpful in telling what those different temperatures look like.

146f35ff205ca337d17d4d6146c3574b.jpg
 
This might sound strange, but try using carbide-tipped concrete bits for holes in the 1/8" to 1/4" range. They work great for me.
 
The easiest way to ge t spheroidized structure is to do a "sub-critical anneal" at 1200 F for2 hours to make sure you have the spheroidized structure rather than pearlite or martensite.Drill your holes then do your normal HT.
 
Fwiw, lots of steels will air harden when at thin profiles like knives.
Slow cooling is the key.
 
mete said:
The easiest way to ge t spheroidized structure is to do a "sub-critical anneal" at 1200 F for2 hours to make sure you have the spheroidized structure rather than pearlite or martensite.Drill your holes then do your normal HT.
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Thank you for your help. I am a VERY MUCH beginning knife maker and do not know what most of this means. :confused:

I followed the advice in the linked thread. I heated it to a dull red and put it in kitty litter to slowly cool. I came back about an hour later and repeated the process. I did this about four times. One of the holes drilled with no problem, but the other was about the same. I'm going to repeat that process today--paying special attention the area around the second hole.

By the way: Why would 1084 steel act like this, but not the 1095 or 15N20?
 
If you are having problems going through any hardened steel you will need to switch to a full carbide drill bit with a coating like TiN or Altin, they will go through anything. You will want to dial your speed down and go slow. Most of the hardware store drill presses spin way too fast and work harden the steel.
 
Pittknife said:
If you are having problems going through any hardened steel you will need to switch to a full carbide drill bit with a coating like TiN or Altin, they will go through anything. You will want to dial your speed down and go slow. Most of the hardware store drill presses spin way too fast and work harden the steel.
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I'm no expert, but my TiNi coated steel bits seem to be no improvement over HSS. My colbolt bits have no coating and cut like butta.
 
Folsoml said:
Thank you for your help. I am a VERY MUCH beginning knife maker and do not know what most of this means. :confused:

I followed the advice in the linked thread. I heated it to a dull red and put it in kitty litter to slowly cool. I came back about an hour later and repeated the process. I did this about four times. One of the holes drilled with no problem, but the other was about the same. I'm going to repeat that process today--paying special attention the area around the second hole.

By the way: Why would 1084 steel act like this, but not the 1095 or 15N20?
Click to expand...

Hey Folsoml, yea the terminology and metallurgical concepts can be a lot to learn all at once, and are definitely confusing. I'm still deep in the book right now trying my best to learn all of the metallurgical concepts that apply to blademaking, and wow, it's dense...but very interesting as well!

Without getting too much into any of that, there are some more basic terms that are great to know, like normalizing, annealing, spheroidizing, etc, and you can at least get a basic concept for why these things are important without getting too much into the deep science of it right in the beginning.

(Check this page here for some good descriptions on Kevin Cashen's site for good and quick explanations of those terms) --> http://www.cashenblades.com/heattreatment.html

Essentially, each steel has a recommended working sequence that should begin with forging, followed by normalizing, followed by annealing before grinding or machining (ie drilling). Going straight from forging to grinding/machining makes things much more difficult. The idea is to prepare your steel to be easy to grind/drill/machine as well as being at a state where it's internally prepared for effective hardening.

As to why the 1084 is acting like that, I'm not entirely sure but perhaps the added Vanadium is maybe culprit? It may be worth normalizing your steel first to get the internal structure all evened out, then attempting the anneal again.

Good luck with that :)
 
Folsoml said:
Thank you for your help. I am a VERY MUCH beginning knife maker and do not know what most of this means. :confused:

I followed the advice in the linked thread. I heated it to a dull red and put it in kitty litter to slowly cool. I came back about an hour later and repeated the process. I did this about four times. One of the holes drilled with no problem, but the other was about the same. I'm going to repeat that process today--paying special attention the area around the second hole.

By the way: Why would 1084 steel act like this, but not the 1095 or 15N20?
Click to expand...

1095 will form carbides and 15n20 will air harden a certain amount. 1084 (Aldo's) has the vanadium which causes the specific issue Kevin was talking about.
 
kdogmcg said:
I'm no expert, but my TiNi coated steel bits seem to be no improvement over HSS. My colbolt bits have no coating and cut like butta.
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coating on hss doesn't work. It's the coated carbide that can cut through anything. I've spent over $3k on different bits and tooling in the last year and the carbide altin can punch through anything, the hss with tin doesn't work for hardened steel.
 
kdogmcg said:
Question, since carbide is really hard, what does the coating add? Does it wear off?
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The finish does wear but it wears significantly less. It also helps retain the edge a lot more to get a better finish.

Here is my take on this, you going to spend hours making a beautiful part, why risk all that work and money instead of spending the extra money on a full carbide coated tool. When I first started I made this handle on one of my first folders, the customer asked for holes after I had spend hours hand rubbing. I was using HSS with a coating and sure enough messed the handle up trying to put the holes in. I've never had that issue with full carbide altin drill bits, they cut like a hot knife through butter.
 
thanks for the input Pittknife. What is your take on Cobalt bits? That's what i have been using, and have been quite pleased. I even had a situation just like yours where I needed to add a pin after the handle was finished and had no issues. Granted, I am only doing a knife every 2-3 weeks on average. I appreciate your input.
 
kdogmcg said:
thanks for the input Pittknife. What is your take on Cobalt bits? That's what i have been using, and have been quite pleased. I even had a situation just like yours where I needed to add a pin after the handle was finished and had no issues. Granted, I am only doing a knife every 2-3 weeks on average. I appreciate your input.
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I tried cobalt as well and they are a little better than hss coated, but not good for my application. I go down to size #54 and was breaking them a lot, and by the time I got down through there was a huge burr which is not acceptable for the detent ball. On the bigger sizes cobalt didn't work for me I had the same issues as coated hss, maybe get halfway through a whole and then all that refinish work.
 
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