Engraving harder steels

[Grizzland]

Hey All!
Hope everyone is doing well.
Have a few questions about engraving into Harder materials such as Blade steels, Alloys and just weird stuff that manufacturers are using for knives.
#1 ( and I should preface this by stating that I am among the growing population that has gone the "inexpensive" route and bought my equipment off of Amazon). I have no problem cutting into aluminums, coppers and bronze. Even mild steel. All of these are beautiful to cut into and have been a great way to practice the trade. I have recently stepped up my game and started cutting into a steel Kershaw knife scale and, !BLAM! I had the rudest of awakenings when all of the techniques I had learned flew out the window as I kept shattering graver tip after graver tip. I am pretty anal about getting my gravers to a polish grind and have played with my setting on my controller enough to figure out my oscillation speed. However, my question is this: is it the material or the cheap gravers that I have purchased? Is it the speed? Is it PSI? All of the above? Any suggestions would be helpful.
I bit the bullet and purchased a GRS 120' C-Max graver and it is coming (hoping it will fit into my knock-off hand piece). And I know that my China made tooling is limited, although it hasn't given me any issues to date. Well until now.
#2 Is There a "one size fits all" graver? (I personally have gravitated to the 120') or is that limiting my ability to do this type of work?
Thank for the help.
I do appreciate the comments
Tim

 

[ByrnBucks]

Good evening Grizzland,

I ran into a similar issue with a kershaw handle, I believe its that some have a bead blasted/ work hardened finish. That was causing all the tip snaps.

The second try on one I took the finish off with maybe 600 or 800 grit sandpaper, then stepped it up 1200, 2000, 3000. It was much more agreeable to cutting afterwards.

A 120 degree graver will serve you well, maybe a 90 for finer shading lines.
Hope this helps Have a great week. BB

 

[AJB]

Novice here, so maybe one of the expert will chime in. The consensus seems to be that hardened blades either cannot be engraved or that they aren’t worth the effort. If you decide to continue, expect frequent shattered graver tips regardless of the graver material.

 

[Grizzland]

If it was the blade, I could understand that. Kershaw uses quality materials for their knife blades. I talking engraving the scales! ( handle ). Incredibly tough.

 

[monk]

most of the knifemakers i worked for sent the blades annealed. even so, some of the blades were just a -itch to work on. if i were to encounter such today, i'd just pass and watch judge judy or some other bonehead.

 

[Grizzland]

most of the knifemakers i worked for sent the blades annealed. even so, some of the blades were just a -itch to work on. if i were to encounter such today, i'd just pass and watch judge judy or some other bonehead.

Ya.. The blades I rarely touch. This is the handle material! Stupid tough.

 

[dhall]

The two key variables to corral are cutter geometry and vibration.
Make sure the work piece is held as rigidly as possible. As the tip of the graver becomes embedded in hard metal as it is cutting, it is more at risk of cracking/fracturing if some force other than simple resistance is encountered. Vibration can introduce or allow lateral forces which can cause the tip to fracture/shear off. The harder the cutter, the more susceptible it will be to cracking and breakage. It likely won't wear away and get dull, it will become fatigued and fail because it has poorer shock resistance. Given that you're using a vibrating cutting device in the form of a power-assisted engraving handpiece, you're already somewhat dancing on the edge of a precipice, and if the object being engraved is allowed to vibrate, too, it's a perfect recipe for tool failure. A harder graver sounds like a good solution, but it requires confident control by the engraver and a firmly-held object in order to succeed.
All things being equal, a more obtuse cutting angle on a cutting tool will be stronger than a more acute cutting angle, so a 120 degree graver should be more resistant to tip breakage than a 90 degree graver. That being said, the other factor that can promote a weaker cutting edge/tip is if the tool/graver is sharpened to a too sharp edge, regardless of cutting angle. It's not immediately obvious, but very slightly blunting the cutting edge/tip makes the tip remarkable tougher. Many sophisticated machine shop cutting tools have a micro-radius on their cutting edges, and we can approximate this with a simple blunting of the graver's tip. A lot of folks call this "dubbing" the tip or point of the graver. Hold the graver vertically or a few degrees less than 90, and with light but even pressure, drag the point a couple of millimeters or about 1/16", and that very steep yet very small angle will make the tip profoundly stronger. Yes, it's a bit harder to see the tip as it enters the metal, and yes, the graver doesn't "bite" into the metal quite as easily, but your tips will last significantly longer in tough-cutting materials. Keep in mind this blunting or dubbing of the point can be quite small and still be very effective. Play around with this a bit and you should find some relief from excessive tip breakage.

Best regards,
Doug

 

[Grizzland]

The two key variables to corral are cutter geometry and vibration.
Make sure the work piece is held as rigidly as possible. As the tip of the graver becomes embedded in hard metal as it is cutting, it is more at risk of cracking/fracturing if some force other than simple resistance is encountered. Vibration can introduce or allow lateral forces which can cause the tip to fracture/shear off. The harder the cutter, the more susceptible it will be to cracking and breakage. It likely won't wear away and get dull, it will become fatigued and fail because it has poorer shock resistance. Given that you're using a vibrating cutting device in the form of a power-assisted engraving handpiece, you're already somewhat dancing on the edge of a precipice, and if the object being engraved is allowed to vibrate, too, it's a perfect recipe for tool failure. A harder graver sounds like a good solution, but it requires confident control by the engraver and a firmly-held object in order to succeed.
All things being equal, a more obtuse cutting angle on a cutting tool will be stronger than a more acute cutting angle, so a 120 degree graver should be more resistant to tip breakage than a 90 degree graver. That being said, the other factor that can promote a weaker cutting edge/tip is if the tool/graver is sharpened to a too sharp edge, regardless of cutting angle. It's not immediately obvious, but very slightly blunting the cutting edge/tip makes the tip remarkable tougher. Many sophisticated machine shop cutting tools have a micro-radius on their cutting edges, and we can approximate this with a simple blunting of the graver's tip. A lot of folks call this "dubbing" the tip or point of the graver. Hold the graver vertically or a few degrees less than 90, and with light but even pressure, drag the point a couple of millimeters or about 1/16", and that very steep yet very small angle will make the tip profoundly stronger. Yes, it's a bit harder to see the tip as it enters the metal, and yes, the graver doesn't "bite" into the metal quite as easily, but your tips will last significantly longer in tough-cutting materials. Keep in mind this blunting or dubbing of the point can be quite small and still be very effective. Play around with this a bit and you should find some relief from excessive tip breakage.

Best regards,
Doug

That is Super Helpful! Thanks so much!
I was always taught to do this on HSS tooling for the machine shop but, I never thought about doing it to the carbide gravers in this application. I've also been using Thermalock material to hold my work so, I don't think its a vibration issue, but I'll double check that.
Again Thanks for the help.
Tim

 

[Old Gunsmith]

I have been using cobalt carbide gravers and sharpening with Lindsay's bulldozer template. It seems to work fairly well on hard frizzens and Ruger's stainless. There is still some point chip but is managable. The bulldozer point seems to work a little better than dubbing. It still requires some experimentation.

 

[Leland Davis]

How are you securing the scale to engrave? dhall is right vibration will kill a point. I have engraved a lot of Kershaw scales on the Leek knife. The bead blasting finish is very hard polish it off. I anneal the scales then polish. Glue them to a hardwood block with hot glue. The inside of the scales have thin spots the glue supports every part of the scale cutting down on vibration. Inexperience breaks a lot of tips that will get better with practice.

 

[Grizzland]

How are you securing the scale to engrave? dhall is right vibration will kill a point. I have engraved a lot of Kershaw scales on the Leek knife. The bead blasting finish is very hard polish it off. I anneal the scales then polish. Glue them to a hardwood block with hot glue. The inside of the scales have thin spots the glue supports every part of the scale cutting down on vibration. Inexperience breaks a lot of tips that will get better with practice.

Hey Leland
Thanks for the tip about Annealing the scale. This was going to be my next experiment since, I'm sure, hardening the scales is done with some type of quenching. This is a small Kershaw Gravel, I believe it has the same finish as the Leek. I have sanded the finish off but I'm still waiting for my GRS 120 graver to arrive. I'll keep everyone posted.
Thanks again
Tim

 

[Old Gunsmith]

I have been securing parts using Bondo (automotive body filler). I secure them to small pieces of wood for holding in the vice. The parts release with some heat from a heat gun. Not much residual residue left. What is left cleans off with the engravers universal solvent - Acetone. The Bondo has less squiggle than hot melt glue. I can't take credit for this tip, I got it from John Schippers.

 

[Grizzland]

I have been securing parts using Bondo (automotive body filler). I secure them to small pieces of wood for holding in the vice. The parts release with some heat from a heat gun. Not much residual residue left. What is left cleans off with the engravers universal solvent - Acetone. The Bondo has less squiggle than hot melt glue. I can't take credit for this tip, I got it from John Schippers.

Thanks for the tip! I do use Thermolocck and it does pretty well. If I realize that this is an issue, ill give it a shot.

 

[Grizzland]

Hey All
Quick update on my Hardened steel project ( Kershaw Gravel Knife Scale )
So after much horsing around with different settings, gravers and all around tom-foolery, I settled on the HSS 120 degree graver I ground myself. The nice thing is, the graver told me when I needed to sharpen it when it tried to "slide" off of the work surface. ( hence a few scratches in the scale ). But, I think it came out pretty well for my first steel project.
In the future, I'm going to really look into Annealing the steel pre engraving. Hoping it gives me a softer cut.

Thanks for all the help!
Tim

 

[Adder]

If you anneal it properly, will even knife steels like 440c and AebL be soft and okey to cut. The handles on Spyderco knives is really okey to cut without annealing.

 

[Grizzland]

If you anneal it properly, will even knife steels like 440c and AebL be soft and okey to cut. The handles on Spyderco knives is really okey to cut without annealing.

I'm not sure. I haven't had the opportunity to try it again as I'm just playing with what I can cut and what I "want to cut". Most of the higher end knives have a coating over the steel handles that make them really tough. Further, biting through this coating seems to destroy the graver, which would make sense. On top of that, I'm speculating that annealing the handle could warp or even destroy the coating on these and make the whole process void. Something I really don't want to do in a $100 knife. Soooo.. I have had success with HSS gravers but have to continually sharpen it as I go. It may be just the fee for doing work on these scales.

 

[416Rigby]

Good morning, I have engraved a few guns that would definetely make bad words come out of your mouth. My advise is M48 blanks, or Carbide. A 50 degree face is what works for me. I would definitely spend the money, and try to find the better quality ones. The ones off of ebay and amazon are chinese, and india made. Poor quality, and I highly doubt the foreign made M48 blanks have 8% colbalt mix in them. GRS also has the X7 cobalt mix which is C70.
Rugers, Certain Smith & Wessons, and Tisas, their steel is definetely hard. I purchased a Digital rockwell hardness tester off of amazon, and it has been a great tool for the shop. Knowing how hard the steel is, really helps me determine which gravers, or blanks to use, or can I engrave it without wearing out my tools.

 

[Grizzland]

Good morning, I have engraved a few guns that would definetely make bad words come out of your mouth. My advise is M48 blanks, or Carbide. A 50 degree face is what works for me. I would definitely spend the money, and try to find the better quality ones. The ones off of ebay and amazon are chinese, and india made. Poor quality, and I highly doubt the foreign made M48 blanks have 8% colbalt mix in them. GRS also has the X7 cobalt mix which is C70.
Rugers, Certain Smith & Wessons, and Tisas, their steel is definetely hard. I purchased a Digital rockwell hardness tester off of amazon, and it has been a great tool for the shop. Knowing how hard the steel is, really helps me determine which gravers, or blanks to use, or can I engrave it without wearing out my tools.

Sweet!
Thanks for the info!
Soooo.. I did get a GRS 120 Degree graver C-max and tried to use it on the same project. AND, it did the same thing; shatter after only a few seconds of cutting. So, as the above suggestions have stated, I started to look at different reasons as to why my gravers were breaking tips so easily. Could it be vibration? Not that I could see. I use Thermolock and it does very well with mounting my work. As it turns out, well, I'm not going to say that my hand pieces are junk but.... they're junk!! What do you expect from a $45 hand piece? What happens is the air pressure, even at 35 psi, is "pushing" on the graver collet and preloading the graver to the work. When I go to press on my foot peddle, the graver "bounces" from the preload and then never sets again to the material, almost instantly causing the tip of the carbide to shatter. Very frustrating. I have tried to hold the collet in place using finger pressure or adding a bit more load pressure to the graver against the material, but I either can't hold it steady enough or I slip and create a huge scratch in the work material.... again, VERY frustrating.
At this point in my blossoming engraving career, I'm just not ready to plop down $1,000 for a hand piece (and I am very hesitant to buy any used one... If I could find one). So, I'll either worry my way through steel with HSS and grind it sharp every inch or so of engraving or, be relegated to doing softer materials (aluminum, brass, copper, etc.). Not the worst case scenario but pretty limiting.... For now.
I have not tried Colbalt gravers but that will be next on my list of things to experiment with.. I can get blanks from Amazon and they are pretty cheap so I'll probably go that route first.... Trial by fire is a great learning tool!
Thanks Again
Tim

 

[Dani Girl]

yep. graver choice, vibration, psi, geometry, technique too.

over my decade plus of engraving I've settled on workholding being the biggest part. not many engravers discuss workholding in stuff jewellers use. ask your local jewellers supplier stores. I got some red setters wax which stinks when you heat it with a torch so I do it outside. the grs pitch cups are the closest thing but the red stuff is slightly harder and more brittle. cheap though. most importantly it can be dissolved out of little crevices. Thermoloc holds better when super heated a bit. warm it...shape it... (mine is held in wood)... press your part in... then heat it some more heating the metal so it really glues to it.. press the part in with a stick or a block of wood with baking paper between. (if you touch thermoloc when it's bubbling you'll be badly injured. ) wait til it's cool/cooler then peel the baking paper off.

experiment with all the graver metals.

I think higher psi is better. what's the max on a palm control? 120? with the heavy piston?

when making your cuts. cut them smoothly and exit the metal gently. don't let the tool sit still tapping an area or it work hardens. push gently and wait when meeting up with another line you've cut.

where's the ballistics gel stuff sit beside all the other options? softer and wobblier than thermoloc? haven't heard much discussion on it.

what's everyone's favorite work holding medium and mounting process for the jobs that won't stop chipping gravers?

 

[Dani Girl]

the red setters wax is just melted off the wax stick into a blob on a bit of wood too. too thin and it shatters from vibration