Thanks for the very kind words and glad it has helped so much! Thank you for all you are doing for the community too! The carbide hammer has saved so many blades for me over the last few years using it. If the blade has an extreme warp, it is still possible to crack it while straightening. I have straightened about 400 blades now and have cracked 5. I think that is some pretty good results.
That’s a lot of blades you used with them. Good to know it’s not 100% guarantee but already it is leaps and bounds over trying to bend it back to straight. Thanks again Kyle, much appreciated 👍
I did a video making my own about a month ago but didnt do a great job explaining exactly how it works, and why you need carbide. Glad you explained it a little better 👍 I thought these were very well known at the time, and didn't need much explanation. But it seems very few people have even heard of this method. If you're working with air hardening steel these are a MUST HAVE. It's amazing how well these work. Good video Jeremy 👍
Cool tip, that intro was pretty funny man! The BBOD the bodyblow of destroyers for metal. Pretty slick little hammer also, thanks for sharing the tip with us!
This is a very well known metal working technique in the world of metal forming, machining, carpentry, and automotive bodywork. All you are doing is stretching the short side forcing it to relax and push the opposite way. This technique is often used to true up metal squares when they are slightly out of square.
It works because it's ever so slightly moving the metal on the inside of the warp. If you stretch the inside metal, it'll push outward and essentially expand that side of the blade, and that's why it straightens it.
I made one from a rock drill carbide inserts, machined up some brass for the head (double ended, one end balled for straightening one end flat for pin peining). Super high toughness carbide. Not all carbide is created equal, you dont want to use brittle carbide when hitting hardened steel, flying shards are no fun.
I have been using Kyle’s hammer about a year and I haven’t had a blade yet I couldn’t straighten I use 440c, Nitro-v. It’s a money and time saver….oh and I haven’t broken a blade yet….
Every hit hardens the surface where you hit it and puts more tension into the metal. You need the carbide when you straighten hardened steel. At my work we use hardened tool steel hammers with a vertical grinded side, for softer steel, wich pushes material and leaves dents (about 0,05mm deep) which need to be grinded away afterwards. For hardened steel wee use vertical grinded carbide hammers which are grinded really sharp. If you use one of these hammers on soft metal, you leave really deep dents. You can also change the flatness of the backside of the blade (width) if it's warped or you want to put or curve in. But at my work we don't flatten knives. We only flatten bigger parts.
You are stretching the material making that side longer thereby causing the bow to straighten. Pretty good idea using a carbide ball brazed in the hammer. Tungsten should work as well. You would want a small cross section face like the ball bearing or a pick. Working the other side, you would need to shrink.
The Japanese have been using this technique for centuries when straightening plane blades before sharpening. There's a ton of videos here on RUclips, showing the process.
Here in Brazil it's a quite known method. I've first seen it on Berardo's channel, a brazilian master smith, and he used a high carbon hardened hammer with no carbide if I remember correctly. Probably doesn't las as long without the carbide, or the blade is tempered first.
I'm curious what the upper limits of uson something like this is because I definitely snapped apart a very thin Damascus kitchen knife that was twisted and warped😂
From my experience, the thinner the steel, the less effective it is. So out at the very tip when ground, you have to use very light hits to get it to work. If you hit harder, it just bends it around the ball. I do all my grinding full thickness after heat treating. I straighten after my cryo and double temper and have not had to do much follow up straightening during grinding. I try to remove steel at the same rate on both sides and have had really good luck. Hope that helps!
Does anyone know if it’s possible to straighten a blade that is already finished? I got a folder in 20cv with a pretty thin hollow grind that is slightly warped and I don’t want to break it lol
So it seems that on the side being tapped with a carbide ball bearing hammer it apparently expands or scratches the surface of that side. The result is that you are able to steer or control the flatness of the knife or even create a curve the other direction if you wish, fascinating :-)
You betcha. I think there is a slight chance that it might shatter pre-temper but sometimes the warp happens during the temper so I think it's best to complete the entire heat treatment process and then straighten the blade.
I actually tried that myself before I order this. I just tried a ceramic belt on my grinder and I wasn't able to even start to grind it down. Maybe another abrasive would work better.
@@HoY_82If you have a silicon carbide belt, that should help with grinding. The rounded ball is really nice because it doesn’t make as severe of a stress concentration in the steel.
@@KHDailyKnives I do have some 400 grit silicon carbide belts, I’m going to try the roughing with an angle grinder and a drill outside. They can be cut like that I’m hoping I can get a bit of shaping done that way too
You always should only the hit the metal on a spot where it has contact with the table or the flat surface you were flatten it on. If you hit it on a position, where it is contact less, you make it worse. If you have a workpiece which is really thin you also can make it come bend up, if you hit it to hard (ruined a 500mm x 1500mm plate this way when I learned it). I hope you guys could understand it, because it's hard to explain in english for mee. Thanks for the great video.
Thanks for the very kind words and glad it has helped so much! Thank you for all you are doing for the community too!
The carbide hammer has saved so many blades for me over the last few years using it. If the blade has an extreme warp, it is still possible to crack it while straightening. I have straightened about 400 blades now and have cracked 5. I think that is some pretty good results.
That’s a lot of blades you used with them. Good to know it’s not 100% guarantee but already it is leaps and bounds over trying to bend it back to straight. Thanks again Kyle, much appreciated 👍
I did a video making my own about a month ago but didnt do a great job explaining exactly how it works, and why you need carbide. Glad you explained it a little better 👍 I thought these were very well known at the time, and didn't need much explanation. But it seems very few people have even heard of this method. If you're working with air hardening steel these are a MUST HAVE. It's amazing how well these work. Good video Jeremy 👍
Hello Alex. Hope you're doing ok. Thanks for the great content, one of the best subscriptions I've ever made.
I saw you vid and made one wasn’t hard to do thanks for the idea
I use a small hammer for planishing. I've been on the fence about this voodoo before watching this video. I'm sold.. gonna give this a go!
Niroc in Australia make a great one 😊
Used mind a few times and it works a great. Need to pick up some of his carbide lunches too
Cool tip, that intro was pretty funny man! The BBOD the bodyblow of destroyers for metal. Pretty slick little hammer also, thanks for sharing the tip with us!
Thank you so much! I’m glad you enjoyed it and thank you for watching 👍
Ooo, candy in the box! Kinda like Sweetwater Sound. (audio online retailer)
Gotta love candy! 👍
i wish we in the states we had a princess auto
This is a very well known metal working technique in the world of metal forming, machining, carpentry, and automotive bodywork. All you are doing is stretching the short side forcing it to relax and push the opposite way. This technique is often used to true up metal squares when they are slightly out of square.
I wish i woulda seen your video this morning… right before i used a similar jig to yours and snapped my aebl sujihiki. Buyin one tonight 100%
It works because it's ever so slightly moving the metal on the inside of the warp. If you stretch the inside metal, it'll push outward and essentially expand that side of the blade, and that's why it straightens it.
I made one from a rock drill carbide inserts, machined up some brass for the head (double ended, one end balled for straightening one end flat for pin peining). Super high toughness carbide. Not all carbide is created equal, you dont want to use brittle carbide when hitting hardened steel, flying shards are no fun.
good job
Thank you! Cheers!
I have been using Kyle’s hammer about a year and I haven’t had a blade yet I couldn’t straighten I use 440c, Nitro-v. It’s a money and time saver….oh and I haven’t broken a blade yet….
Every hit hardens the surface where you hit it and puts more tension into the metal. You need the carbide when you straighten hardened steel. At my work we use hardened tool steel hammers with a vertical grinded side, for softer steel, wich pushes material and leaves dents (about 0,05mm deep) which need to be grinded away afterwards. For hardened steel wee use vertical grinded carbide hammers which are grinded really sharp. If you use one of these hammers on soft metal, you leave really deep dents. You can also change the flatness of the backside of the blade (width) if it's warped or you want to put or curve in. But at my work we don't flatten knives. We only flatten bigger parts.
You are stretching the material making that side longer thereby causing the bow to straighten. Pretty good idea using a carbide ball brazed in the hammer. Tungsten should work as well. You would want a small cross section face like the ball bearing or a pick. Working the other side, you would need to shrink.
The Japanese have been using this technique for centuries when straightening plane blades before sharpening. There's a ton of videos here on RUclips, showing the process.
Here in Brazil it's a quite known method. I've first seen it on Berardo's channel, a brazilian master smith, and he used a high carbon hardened hammer with no carbide if I remember correctly. Probably doesn't las as long without the carbide, or the blade is tempered first.
It's a shrinking hammer. Auto body guys do it all the time. I never thought of it in a knife making context.
I'm curious what the upper limits of uson something like this is because I definitely snapped apart a very thin Damascus kitchen knife that was twisted and warped😂
From my experience, the thinner the steel, the less effective it is. So out at the very tip when ground, you have to use very light hits to get it to work. If you hit harder, it just bends it around the ball.
I do all my grinding full thickness after heat treating. I straighten after my cryo and double temper and have not had to do much follow up straightening during grinding. I try to remove steel at the same rate on both sides and have had really good luck.
Hope that helps!
Here in Brazil is something very usual to use this strategy here to solve our blades 😃👍
When you grind off the marks you are removing the restoring force and the distortion can return.
YES !!!
👍
Excellent explanation.
Any chance of some more work with the venerable TSPROF KO-3?
Thanks, and take care friend...
Make sure you only start straightening after temper
That only makes sense. Somethings the warps happen during the temper.
I've seen so many people trying to use it after quench and than break their blade. It makes me so sad! @@Simplelittlelife
So if you have someone who is bent, you hit the bent part and they become straight?😊
ive broken 2 out of 3 blades i tried it with now ..with only minor warps, anny tips? is it safer to do it at tempering temperatures?
I believe you're de-stressing the steel. Auto-body guys do something similar.
Does anyone know if it’s possible to straighten a blade that is already finished? I got a folder in 20cv with a pretty thin hollow grind that is slightly warped and I don’t want to break it lol
So it seems that on the side being tapped with a carbide ball bearing hammer it apparently expands or scratches the surface of that side. The result is that you are able to steer or control the flatness of the knife or even create a curve the other direction if you wish, fascinating :-)
*stretches
You can make your own it’s easy you can buy a carbide ball and drill a hole in a old hammer use a punch to crimp edges of hole bingo
Unless you forge you have no idea Lol
Problem is it creates hundreds of little divets
Which take a minute to correct on a grinder. It’s a way smaller problem than a broken blade. These are the way to go in my experience.
My girl started an argument over a butter knife today. As you might expect, it was pointless.
U do this after tempering correct? I feel u could shatter it if pre tempering
You betcha. I think there is a slight chance that it might shatter pre-temper but sometimes the warp happens during the temper so I think it's best to complete the entire heat treatment process and then straighten the blade.
Very cool! Mine is arriving next week. This is done after tempering right? Thanks
Yes it was
That technique makes so much sense. I haven’t gotten to make many knifes but good to have that in the back pocket for sure.
I might try to make one of these with a broken 1/2" carbide endmill, if I can manage to grind a dome into the end of it!
I actually tried that myself before I order this. I just tried a ceramic belt on my grinder and I wasn't able to even start to grind it down. Maybe another abrasive would work better.
@@Simplelittlelife I'm probably doomed to fail as well then! cant resist but to try at least.
@@HoY_82If you have a silicon carbide belt, that should help with grinding. The rounded ball is really nice because it doesn’t make as severe of a stress concentration in the steel.
@@KHDailyKnives I do have some 400 grit silicon carbide belts, I’m going to try the roughing with an angle grinder and a drill outside. They can be cut like that I’m hoping I can get a bit of shaping done that way too
It was great, thank you for your efforts dear friend for this video. good luck always
Creely Blades did a video about this some time back, but I don't think he used a carbide tipped hammer.
You always should only the hit the metal on a spot where it has contact with the table or the flat surface you were flatten it on. If you hit it on a position, where it is contact less, you make it worse. If you have a workpiece which is really thin you also can make it come bend up, if you hit it to hard (ruined a 500mm x 1500mm plate this way when I learned it). I hope you guys could understand it, because it's hard to explain in english for mee. Thanks for the great video.