Post by: tippit on January 24, 2008, 02:41:00 PM
(http://img.photobucket.com/albums/v110/tippit/Knives/52100002.jpg)
Post by: vermonster13 on January 24, 2008, 02:57:00 PM
Post by: tippit on January 24, 2008, 04:17:00 PM
(http://img.photobucket.com/albums/v110/tippit/Knives/52100.jpg)
Post by: sticshooter on January 24, 2008, 05:07:00 PM
Post by: Lin Rhea on January 24, 2008, 07:03:00 PM
I have an email out to a friend who is an expert on 52100. Let's see what he says first. Lin
Post by: tippit on January 24, 2008, 07:49:00 PM
Post by: Lin Rhea on January 24, 2008, 08:10:00 PM
52100 is not for the faint of heart. That's why I wanted to holler at Ray Kirk MS. He uses 52100 almost exclusively and is one of the best athorities on it's use for blades. I sent you a copy of his email.
For those of you who would be interested, he said that 52100 has to be worked hot and within a range of heat. If you work it too cold it will crack like that. Lots of steels will crack when worked too cold, but especially is 52100 prone to. Also, typically edge packing is done as the heat is reducing, which entering the danger zone, temperature wise, so he recommends NOT edge packing this steel.
If you get it too hot while forging, it could splatter while being hit. White hot is too hot. I figure orange to bright orange is a good color to forge it. Red to bright red is a good forging temp for most steels, but probably too cold for 52100.
Every steel has it's peculiarities and part of the fun is figuring it out.
Lin
Post by: tippit on January 24, 2008, 08:18:00 PM
Post by: tippit on January 24, 2008, 08:33:00 PM
Post by: 4runr on January 24, 2008, 09:57:00 PM
Post by: tippit on January 25, 2008, 08:10:00 AM
Post by: tippit on January 25, 2008, 04:03:00 PM
So when I quenched it I had my usual gloves and eye protection not knowing what to expect. That seemed to go pretty smooth. I edge quenched and pulled it out when the color went dark. Then let it air cool as apposed to putting it down in the oil. This was Ray Kirk's & Lin Rhea's recommendation. It will be interesting to see what this edge is like compared to my usual steel...5160 & 1080. 52100 is ball bearing high carbon steel...very tough stuff. Many thanks to Lin for getting me thru this :notworthy: Doc
(http://img.photobucket.com/albums/v110/tippit/Knives/52100004.jpg)
Post by: Lin Rhea on January 25, 2008, 06:11:00 PM
Did you try it with a file? Lin
Post by: tippit on January 25, 2008, 07:50:00 PM
Post by: Lewis Brookshire III on January 25, 2008, 07:57:00 PM
Post by: tippit on January 25, 2008, 08:56:00 PM
I would have sworn that the blade would be too soft...purple color & file will cut. So I couldn't wait til morning...after all my wife is in SC for 3 months, so what's an old man supposed to do on a Friday night :rolleyes: Yep back to the shop. I ground an edge and the tried to sharpen with my never fail Gatco system. Still too hard :knothead: It's going back into the oven @ 455 = 470. I'll try again.
In this picture, the blade has a pattern of it's own...circular swirls not my grinding pattern. This stuff is challenging, frustrating, and lots of fun! Doc
(http://img.photobucket.com/albums/v110/tippit/Knives/52100006.jpg)
(http://img.photobucket.com/albums/v110/tippit/Knives/52100007.jpg)
Post by: Lin Rhea on January 25, 2008, 09:30:00 PM
I'm learning too. After you tried the Gatco, did you try the file again? I'm thinking there was a layer of decarborized steel on the surface. This can be typical and quite normal. This layer is softer due to the loss of carbon. Once you file through it the blade is really hardened. In this case still too hard.
The picture looks like you have a start on the bevel anyway.
Lin
Post by: tippit on January 25, 2008, 09:49:00 PM
I used the the file before I ground my edge on my KMG. The bevel is right there but the Gatco couldn't put an edge on it. If I had color like this on 5160, I could probably put an edge on it with soap stone :) I usually temper 5160 at 375 for blades and 400-420 for forged broad head so they are easy to file sharpen. I'm now getting close to 500 mark on this one.
I'm sure glad Ray gave some guide lines on tempering 52100. In my limited experience, this just blows me away! She's baking now...tippit
Post by: tippit on January 25, 2008, 09:57:00 PM
52100 Spec Sheet for anyone interested:
AISI 52100
Alloy Steel
Typical Chemistry
Carbon 1.00%
Manganese 0.35%
Silicon 0.25%
Chromium 1.50%
Typical Applications
Bearings Gauges
Draw Dies Mandrels
Drills (Non-Ferrous) Taps (Hand)
Forming Tools Threading Dies (Hand)
--------------------------------------------------------------------------------
Annealed Hardness: BHN 183/212.
Thermal Treatments
Critical Temperature: 1385F (750C)
Annealing: 1440F (780C), hold 2 hours, slow cool 25F(15C)/ hr max. to 1200F(650C), then air or furnace cool. Hardness BHN 183/212 Stress Relieving
Annealed Material: 1100-1300F(595-740C), hold 2 hrs, air cool.
Hardened Material: 50-100’F(30-55’C) below last tempering temperature, hold 2 hrs, air cool.
Straightening: Best done warm 400-600F (205-315C).
Hardening: (Atmosphere or Vacuum Furnace).
Preheat: 1200-1250F (650-675C), equalize.
High Heat: 1500-1550F (815-845C), soak 10 to 30 minutes. For vacuum or oil hardening, use the high side of the high heat range and soak times. Use the low side of the temperature range for water hardening.
Quench: Oil or water quench to hand warm, 150F (65C). Temper immediately.
Temper: Tempering at 300-500F (150-260C) for at least 2 hours at temperature is recommended. Air cool to room temperature after tempering.
Physical Properties
Modulus of Elasticity ........................................30 psi x 106 (207GPa)
Specific Gravity ................................................................................7.85
Density ...........................................................0.283 lb/in3 (7850kg/m3)
Post by: sticshooter on January 25, 2008, 10:11:00 PM
Post by: Doug Campbell on January 26, 2008, 12:23:00 AM
Did Ray happen to say what temps he's forging this stuff at??
Got another couple feet of this cool stuff not to mention five or six of the John Deere load shafts.... Lots more fun!!
Post by: Lin Rhea on January 26, 2008, 07:05:00 AM
I too dont think Jeff got it too hot, but the steel ( according to Ray) will get those ice like cracks in it when you continue to hammer on it after it's too cool. Whatever the range is, and your equipment, lighting, forge, etc. along with your particular experience using this steel, you have to play by it's rules. This might take a little time to play around with and get right. Ed knows his stuff, for sure. I'm thinking that there are two parts of this process that Jeff needs to adjust. Deciding what levels of temperature range and staying in that range while hammering.
Jeff, just as you know the particulars of 5160 , you'll get to know 52100.
I would do some test pieces (not actual blades) and get to where I'm satisfied that I can duplicate the results. Taper a few pieces of 52100 and do each one a little different, keeping up witht he particulars for each. What do you think? Lin
I'll be awy for the day. Some more makers and myself are going to Little Rock to the Big Buck Classic and do some forging and cutting for the folks attending. I hope to have some photos soon. Thanks
Post by: tippit on January 26, 2008, 10:03:00 AM
I know I'll have to make some adjustments on the next 52100 blade...less hammering, no packing of the blade edge, and working it hotter & quicker. It's been fun trying something new. Especially since this steel is highly regarded in holding an edge. All in all it has been a really great experience with the friendly help here.
Now to test the blade...Got Buffalo Doug? Doc
(http://img.photobucket.com/albums/v110/tippit/Knives/52100011.jpg)
Post by: d. ward on January 26, 2008, 10:50:00 AM
Post by: Doug Campbell on January 26, 2008, 10:56:00 AM
I got ya Lin, I do remember Ed saying it was a pretty narrow window for forging, guess cause he was starting at such a low temp. Hope you had a great turnout for the show today.
Post by: tippit on January 26, 2008, 11:28:00 AM
!["[dntthnk]"]("graemlins/dntthnk.gif" "\"\"")
...the other Doc
Post by: d. ward on January 26, 2008, 11:51:00 AM
Post by: Montauks on January 29, 2008, 09:03:00 AM
Grasshopper