Hock blade issue
#9
I have been using Hock plane blades over the past 20 years with no issues. I have a #3 that I picked up a few years ago, but set it aside and let it collect dust. A few weeks back, decided to get it in working order. Blade was pitted pretty bad so I ordered a Hock blade for it. Cleaned up the back and honed the edge. I did notice that while I was able to get it sharp, it was not getting quite as sharp as I like.  Tested it on some scrap wood. First pass worked, then subsequent passes, nothing but scrapped dust.  Inspected the edge and it was crumbled. 

I sharpened it again, but the edge crumbled. 

Ground the bevel on the Tormek and honed the edge as normal.  Again, the same problem.

Did a little more work on the back, and sharpened again. I will say that the blade was very flat to begin with so that did not take much effort.

Again, the same problem.  

Last thing I tried last night was grinding away some material on a CBN wheel. Going into the shop today to focus on that plane and see if I can get to the point of good steel on the blade. I have probably removed a touch more than 1/32” of the edge at this point. I have had this problem with a 1-1/2” Ray Iles chisel before, but never had this issue with Hock irons. 

Whats the chances that it is only the edge of the steel versus the entire blade having a bad steel/heat treatment?
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#10
(02-08-2025, 10:10 AM)Scoony Wrote: I have been using Hock plane blades over the past 20 years with no issues. I have a #3 that I picked up a few years ago, but set it aside and let it collect dust. A few weeks back, decided to get it in working order. Blade was pitted pretty bad so I ordered a Hock blade for it. Cleaned up the back and honed the edge. I did notice that while I was able to get it sharp, it was not getting quite as sharp as I like.  Tested it on some scrap wood. First pass worked, then subsequent passes, nothing but scrapped dust.  Inspected the edge and it was crumbled. 

I sharpened it again, but the edge crumbled. 

Ground the bevel on the Tormek and honed the edge as normal.  Again, the same problem.

Did a little more work on the back, and sharpened again. I will say that the blade was very flat to begin with so that did not take much effort.

Again, the same problem.  

Last thing I tried last night was grinding away some material on a CBN wheel. Going into the shop today to focus on that plane and see if I can get to the point of good steel on the blade. I have probably removed a touch more than 1/32” of the edge at this point. I have had this problem with a 1-1/2” Ray Iles chisel before, but never had this issue with Hock irons. 

Whats the chances that it is only the edge of the steel versus the entire blade having a bad steel/heat treatment?
There is probably an issue with the heat treatment phase of the blade, but one can't rule out bad steel. I think originally hock Blades were made out of AISI 1095  and later 01. I do not know which blade you have.  1095 is a water quench, if my memory is correct,  and 01 in an oil quench.  01 is difficult is a difficult tool steel to heat treat without an atmospheric furnace and an adjugated bath of a proper quenching oil. I did not say it couldn't be done only that it is difficult

I would contact the company you purchased it from and see about an exchange. Things do happen during production and are not caught. Sorry to hear of your problem, I tend to purchase Hock blades myself.

Tom
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#11
Tom, I believe it is O1 as the the other Hock Blades I have. The last Hock blade I got was well over 5 years ago. Matter of fact, the one in my #5 is getting to the point where I will need a replacement soon.

I tried again this morning and even went so far as to regrind the bevel from 25 to 30 deg. It was then that I realized that the steel was grinding away too fast for a Tormek. Also noticed that when stroping the wire edge, it kept going back and forth like soft steel will do.

I am pretty sure that this was not heat treated properly. I got it from Tools for Working Wood and will be calling them on Monday.

BTW, the #3 is a type 12. The original blade was mushroomed as they often are, and pitted as well. The good part is the wood is nice shape, the black enamel is 100%, and the sole cleaned up fast and easy. I did clean up the original blade a little more, but some pitting near the edge remains. Works fine, but I really do not like using the back bevel for sharpening.
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#12
(02-08-2025, 01:32 PM)Scoony Wrote: Tom,  I believe it is O1 as the the other Hock Blades I have. The last Hock blade I got was well over 5 years ago. Matter of fact, the one in my #5 is getting to the point where I will need a replacement soon.

I tried again this morning and even went so far as to regrind the bevel from 25 to 30 deg.  It was then that I realized that the steel was grinding away too fast for a Tormek. Also noticed that when stroping the wire edge, it kept going back and forth like soft steel will do.

I am pretty sure that this was not heat treated properly.  I got it from Tools for Working Wood and will be calling them on Monday.

BTW, the #3 is a type 12.  The original blade was mushroomed as they often are, and pitted as well. The good part is the wood is nice shape, the black enamel is 100%, and the sole cleaned up fast and easy. I did clean up the original blade a little more, but some pitting near the edge remains. Works fine, but I really do not like using the back bevel for sharpening.
......
I would try filing the edge..use a sharp file...if you can abrade the steel with the file, it's too soft...a sharp file should just "skate" across the bevel..If you can't return the blade, you can try to re-harden it..Use a Mapp torch, heat the bottom inch of the blade until it is cherry red {in daylight} then quench it in any kind of oil. Shine the blade up and play a soft flame on the part you have hardened,,watch for the color of the steel to travel towards the bevel,,,then quench it in oil when it is a straw yellow color. If properly hardened, you should not be able to file the steel. If it passed the test, go ahead and restore the bevel and sharpen it. I have done many edge tools that way.
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#13
What Timberwolve says is true to a certain degree, But at Cherry red ( about 1475F) there will be a black film forming very quickly and when it happens it is oxygen in the air coming in contact with the steel steel, decarbing the metal. I have used this process in a pinch to do small parts like round locators.  But usually they were carburized or carbon nitrated. 

In an atmospheric furnace,  the oxygen is replaced with other noncombustible gases and the metal is allowed to be held in the austenite range for the proper time. I do have enough experience with 01 failures trying to HT with a torch, so I avoid it as much as I can. But when Heat treating A2 the general practice is to allow it to stay at temp (1750-1800) normally 1750 1 hour per inch thickness in the austenite range before quenching. I know that 01 is a full hardening steel and it needs to be held at hardening temperature for much longer that the torch system allows. 

I have much more experience with A2, D2 ,M4, S7 and the later CPM steels, which are actually powdered metallurgy. We did have an atmospheric furnace at Hawkeye Community College where I thought a semester of heat treatment once every two years. And the proper way to reheat treat steel is  to fully anneal it first, which wasn't mentioned.

I would advise you to contact the place where you purchased it and get it hopefully replaced or refunded. Going the other way will void any chance of getting a replacement other than buying another blade.  So I guess the choice is yours, because I along with the rest who have responded do not have a pony in the show.

Tom
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#14
Just got off the phone with TFWW and they are shipping me out a new blade today with a return label for this one.

I can heat treat small blades, such as side escarpment and grooving plane blades. In this case, I would rather let them replace it. I am just hoping that the replacement was not beside this blade in the production line. That would be just my luck.
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#15
Follow up.
TFWW sent me a new blade which arrived Friday. Cleaned up the back, and sharpened it. Seems to work perfect and holds the edge.
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#16
(02-15-2025, 09:20 AM)Scoony Wrote: Follow up. 
TFWW sent me a new blade which arrived Friday.  Cleaned up of the back, and sharpened it. Seems to work perfect and holds the edge.

I think it was the correct choice on how to handle it. It is always a good choice to let the supplier have first chance at taking care of the problem. It seems that the problem, that was beyond their control, ( producing the part) was taken seriously and remedied to your satisfaction. It sounds like a good company to buy from.

Tom
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