Cut 1018 steel 9/16" diameter bar

[BluntCut MetalWorks]

Is it possible to cut 9/16" dia bar of 1018 steel using blade with edge: 20 dps, 0.020"-0.025" behind edge thickness, where edge afterward would still able to slice printer paper?

*cut to the red-line, rather than all the way through to avoid edge impact on anvil/hard-backing
*blade can be in any steel and at whatever hardness necessary

If you think - yes, appreciate share how/approach? I am preparing test blades for ht and may be ready to tackle this task/challenge in 2 weeks.

 

[tkroenlein]

Did you read this?

https://knifesteelnerds.com/2019/07/08/frank-j-richtig/

I think there is discussion in a thread here, too, beyond what was in the article.

 

[DevinT]

Part of the secret to Richtig’s cutting was that he cut the rod/bar at the edge of the anvil allowing the bar to bend as he cut through avoiding wedging.

Hoss

 

[BluntCut MetalWorks]

Yes, I did a couple times before. Also have decent amount of knowledge about Frank Richtig. Recently, a friend gave me a F Richtig knife to test. Unless, I raid the museum where Richtig's knife and demo materials, there isn't much I assert whether or not knife or material are legit/real/untampered.

Did you read this?

https://knifesteelnerds.com/2019/07/08/frank-j-richtig/

I think there is discussion in a thread here, too, beyond what was in the article.

 

[BluntCut MetalWorks]

Thanks. I agreed. Nevertheless, even with avoid wedging setup, cut this much metal and edge still slice printer paper is challenging. Has anyone able to accomplish this feat?

Part of the secret to Richtig’s cutting was that he cut the rod/bar at the edge of the anvil allowing the bar to bend as he cut through avoiding wedging.

Hoss

 

[DevinT]

Thanks. I agreed. Nevertheless, even with avoid wedging setup, cut this much metal and edge still slice printer paper is challenging. Has anyone able to accomplish this feat?

Bob Kramer with a chefs knife made from 52100.

Hoss

 

[BluntCut MetalWorks]

Please provide links/refs, thanks. I didn't find relevant info with google searches.

edit: I found this, where BK cut 1/4"(6mm) diameter bolt: https://www.newyorker.com/magazine/2008/11/24/sharper. Whereas this bar diameter is 14.3mm, is about 5.7 times the cross section area of 6mm bolt

Bob Kramer with a chefs knife made from 52100.

Hoss

 

[DeadboxHero]

Should be fun, excited to see what you find.

I'd probably go .250 on the spine, saber grind yet still hit the bte and run hardness ~63rc

Where did you get the steel bar?

Is it possible to cut 9/16" dia bar of 1018 steel using blade with edge: 20 dps, 0.020"-0.025" behind edge thickness, where edge afterward would still able to slice printer paper?

*cut to the red-line, rather than all the way through to avoid edge impact on anvil/hard-backing
*blade can be in any steel and at whatever hardness necessary

If you think - yes, appreciate share how/approach? I am preparing test blades for ht and may be ready to tackle this task/challenge in 2 weeks.

 

[BluntCut MetalWorks]

I ordered 1018 steel hexagonal bars (dia: 9/16", 5/8", 3/4") from: https://www.ebay.com/str/Oakland-Steel?_bkw=1018

I've some choppers blanks at .250" thick however this incoming ht batch#3 already has 34 blades, so these thicker blanks will be in later batch. Good calls on saber grind and ~63rc hardness. The 2 blades from batch#2 are at 63rc, they performed other tests well in spite of low quality prepared edge geometry. Will give these 2 blades a few attempts at this difficult test.

Test blade candidates in Batch#3, I aim for 64-65rc hardness. If chipped when cut 5/16" or 3/8" or 1/2" rebar, will lower hrc. https://i.imgur.com/x2sEPiH.jpg Blades [1095, 26c3, w2, O1, Cfv] are 0.100 - 0.140" thick.

I've 63rc 8670 test knifes(my earlier ht and control/baseline) somewhere... these 2 are very tough but to be seen how they fare

Should be fun, excited to see what you find.

I'd probably go .250 on the spine, saber grind yet still hit the bte and run hardness ~63rc

Where did you get the steel bar?

 

[BluntCut MetalWorks]

HT 5C&D of intended blades for this test were mostly FAILED, except for 2 testable(so so result) ~64rc W2 blades. HT 5E (re-ht and additional few new blades) is in progress.

I tested a few anvil/backing setup(with vise to hold test piece) to minimize wedging. Hammer strike & edge steering are difficult to control, thus easier lead to edge damage = failed test. Upcoming test will cut a short ~3/8" wide chunk of steel rod(bandsaw cut) against curved/convex anvil face.

Cutting 8-10mm dia mild steel rod is plausible, while low probable to successfully cut 12-15mm dia mild steel rod.

Here is a visual steel rod size comparison

 

[DeadboxHero]

Do you know the chemistry of the W2 used, looks fun man.

HT 5C&D of intended blades for this test were mostly FAILED, except for 2 testable(so so result) ~64rc W2 blades. HT 5E (re-ht and additional few new blades) is in progress.

I tested a few anvil/backing setup(with vise to hold test piece) to minimize wedging. Hammer strike & edge steering are difficult to control, thus easier lead to edge damage = failed test. Upcoming test will cut a short ~3/8" wide chunk of steel rod(bandsaw cut) against curved/convex anvil face.

Cutting 8-10mm dia mild steel rod is plausible, while low probable to successfully cut 12-15mm dia mild steel rod.

Here is a visual steel rod size comparison

 

[BluntCut MetalWorks]

Blades are Aldo W2 old batch: 0.93%C, 0.08%Cr, 0.17%V, 0.003%W, 0.012%Mo, 0.23%Mn, 0.21%Si, 0.07%N, 0.01%P, 0.06%Ni, 0.01%Al
I've some w2 in new batch with composition currently listed on their site. At any rate, I found no differences between batches, well - at least from my experiments & testings.

Do you know the chemistry of the W2 used, looks fun man.

 

[DeadboxHero]

Blades are Aldo W2 old batch: 0.93%C, 0.08%Cr, 0.17%V, 0.003%W, 0.012%Mo, 0.23%Mn, 0.21%Si, 0.07%N, 0.01%P, 0.06%Ni, 0.01%Al
I've some w2 in new batch with composition currently listed on their site. At any rate, I found no differences between batches, well - at least from my experiments & testings.

Nice, I got some of the old batch as well.

 

[Natlek]

Is it possible to cut 9/16" dia bar of 1018 steel using blade with edge: 20 dps, 0.020"-0.025" behind edge thickness, where edge afterward would still able to slice printer paper?

*cut to the red-line, rather than all the way through to avoid edge impact on anvil/hard-backing
*blade can be in any steel and at whatever hardness necessary

If you think - yes, appreciate share how/approach? I am preparing test blades for ht and may be ready to tackle this task/challenge in 2 weeks.

0,020-0,025 = 0,5-0,635 mm , right ? Pretty thick @bluntcut , i have some question for you if you don't mind answering them ? I just forged this blade from SKF ballbearing steel , that bearing was Bainite structure .SKF claim that it can go over 60 Hrc if i remember correctly.I forge that ball bearing outer race on 1050 Celsius . Then I make one normalization on 885 Celsius for 10 minutes and then one on 840 Celsius .I cut piece of forged part and austenitize on 835 Celsius and quench in pure water .It break like glass, easy ...I take pictures and i like structure , very very fine grain .What do you think , pictures a good i hope so you can see what I cooked
NOW questions ..........First one is what do you think if I quench blade in oil and then right in the tempering oven.....I want Bainite .DO you think that it would work HT oven + tempering oven .If you think it would work ....what austenitize temperature you recommend and how long / blade is 5mm thick , i will HT first then surface grind and bevels/ And what temperature in Tempering oven and how long ...Time is not problem , if necessary I can leave it for a week.I want to cut that
9/16" diameter bar . I forge one other piece from ordinary SKF ball bearing so i can make comparision if if I succeed to get Mister Bainite .....Last question , how i would know that i have Bainite , is there some simple test ,which i doubt

What do you think ?

 

[BluntCut MetalWorks]

0,020-0,025 = 0,5-0,635 mm , right ? Pretty thick

When cut deep into hard & dense material, wedging is essential to avoid material pinch(like a plier) the edge, otherwise edge failure is guarantee. 0.017" to 0.025" edge shouder depends on depth of cut.

i have some question for you if you don't mind answering them ? I just forged this blade from SKF ballbearing steel , that bearing was Bainite structure .SKF claim that it can go over 60 Hrc if i remember correctly.I forge that ball bearing outer race on 1050 Celsius

Upon first heating, bainite is gone. *not for you. I just stating the obvious for others to aware of.

Then I make one normalization on 885 Celsius for 10 minutes and then one on 840 Celsius .I cut piece of forged part and austenitize on 835 Celsius and quench in pure water .It break like glass, easy ...I take pictures and i like structure , very very fine grain .What do you think , pictures a good i hope so you can see what I cooked

Yes, extra fine grain. Surface indicates intragrainular fracture. Yup. glass like.

NOW questions ..........First one is what do you think if I quench blade in oil and then right in the tempering oven.....I want Bainite .DO you think that it would work HT oven + tempering oven .If you think it would work ....what austenitize temperature you recommend and how long / blade is 5mm thick , i will HT first then surface grind and bevels/ And what temperature in Tempering oven and how long ...Time is not problem

Yes, just make sure blade quenched cool to below ~800F/426C before put in tempering oven. Have a pair of small quench plate in oven, to rapidly(avoid upper & mid bainite xform) cool your blade toward bainite transformation temperature. For prior aust grain size as shown (in sample), ~58rc ideal lower bainite temperature be between 220c-240c. Coarser grain = 235-265c. Soak 2+hrs. *note: temp too low = more mart%.

, if necessary I can leave it for a week.I want to cut that 9/16" diameter bar . I forge one other piece from ordinary SKF ball bearing so i can make comparision if if I succeed to get Mister Bainite .....Last question , how i would know that i have Bainite , is there some simple test ,which i doubt
What do you think ?

After bainitic soak, air or water cool to ambient. check bainite hardness.
Put blade in temper 145C oven for at least 30 minutes. water cool to ambient. check final hardness(duplex hardness). net mart hrc = final-bainite.

 

[Natlek]

Yes, extra fine grain. Surface indicates intragrainular fracture. Yup. glass like.


Yes, just make sure blade quenched cool to below ~800F/426C before put in tempering oven. Have a pair of small quench plate in oven, to rapidly(avoid upper & mid bainite xform) cool your blade toward bainite transformation temperature. For prior aust grain size as shown (in sample), ~58rc ideal lower bainite temperature be between 220c-240c. Coarser grain = 235-265c. Soak 2+hrs. *note: temp too low = more mart%.

Thanks my friend Intergranular fracture is good i hope ?
About quench plate , just to be sure ....they ARE on same temperature as temperature in the oven/235 Celsius / right ?

 

[BluntCut MetalWorks]

Intergranular reflects higher toughness than intragranular. Your sample is intragranular (in my prev reply). Fine grain conducive to higher plate mart%, thus crack initiate and propagate along plate = across a grain (intragranular). This is obvious, once you think about it.

Yes, plates are at oven temp.

Thanks my friend Intergranular fracture is good i hope ?
About quench plate , just to be sure ....they ARE on same temperature as temperature in the oven/235 Celsius / right ?

 

[BluntCut MetalWorks]

It took me around 17 months of R&D to "sort of" accomplished this challenge/quest.... after test edge certainly failed slice printer paper

Here it is cutting 19mm diameter hexagon mild steel rod.

 

[FredyCro]

Edit: edited my stupid joke because i didn't see the thread was revived for results on the test.

It looks like the edge took minimal damage after such an abusive test, impressive!

 

[BluntCut MetalWorks]

Edit: edited my stupid joke because i didn't see the thread was revived for results on the test.

It looks like the edge took minimal damage after such an abusive test, impressive!

Thanks. In a few days, I plan to redo this edge at 20dps and try to cut 9/16" dia steel rod, but I don't think after test edge would successfully slice printer paper.

Per pre-edit msg/joke about Richtig. Recently I tested a Richtig's knife -- has similar shape as the one attached Unfortunately and obviously, it wasn't anywhere close to the one in picture because it couldn't even cut 1/16" diameter wire. Also this cutting use the 90* edge of the anvil against the knife edge act like a bolt cutter, which is a lot easier make the cut as in picture. One could call this as unspecified technique or trick

Nevertheless, here is a video for what that knife can do at 18dps