Advice: Sharpening Carbide Gravers

[sderek]

I'm in the market for something to sharpen my carbide gravers. What do you use? Where can I purchase one?

 

[Smudgy]

I use a super-fine Eze-Lap for removing a lot of material (broken tips), and a Barkus wheel for final sharpening (the lap leaves the edge with small chips). The Eze-Laps are available from hardware stores and woodworking supply vendors. I don't think the Barkus wheel is made anymore, but the Waller system (similar) is available at the larger watch material supply houses.

 

[sderek]

Will they fit a standard bench grinder?

 

[Don Dahlberg]

You might find this previous discussion useful.

https://mb.nawcc.org/showthread.php?t=55826

Don

 

[Neuron]

I've had good results using Dia-Sharp diamond "stones" with a Crocker graver sharpening jig. The Dia-Sharps are very flat and heavy compared to the other brands. I use a 120grit to quicklytrue up badly chipped tips, then go to a 1200grit for honing. The Crocker jig is fully adjustable and makes it easy to get a precisely angled cutting surface. H2O is used as a lubricant, and since you're sharpening by hand overheating is easily avoided. Works great on HSS, Cobalt, and Carbide tools.

I generally don't like to use machine driven sharpeners, except for my Makita water stone machine, which works great for chisels and plane blades when I'm in a hurry. The Makita stone is horizontally mounted and you grind on the flat. Never use a "regular" bench grinder; it cuts a concave surface, and will overheat the tool.

I know you can put laps on your watch lathe to grind tools, but I don't use them because I worry about getting gritty sludge that could muck up the bearing surfaces.

 

[sderek]

Many thanks to all who replied!

 

[Dr. Jon]

I use methods similar to neurons. I add another item to my "kit". I use a granite floor time on my work surface and use the lap and crocker tool. This prevents the table surface from wearing. This is not just aesthetic.

The laps need to be at the same height. As the surface wears the edge wanders.

I also use a diamond wheel. At NAWCC school we made a jig to hold gravers at the wheel so you can check the grind and re-apply i tto the wheel without losing surface.

When I use this, I put the wheel in a ferrule mounted directly to a motor. I do not use a lathe. I mounted the motor to an aluminum plate and cemented a brass tube to hold the jig.

There is another tool you might consider, and I now use it a lot. There is a graver jig that has wheels. It rolls on the sharpening surface. I clean it pretty carefully between laps to reduce cross contamination. Thsi wiorks well for lozenge tools with a long more acute edge. Shorter tools are do not work well with this as the tip tends to catch and cause end rounding.

I use daimond laps that do not have the swarf catching holes. I get them from teh same maker to assure that they the same thickness. I have 240, 600, 1200, 2400 and 6000 grit lap.

One other thing to consider is what carbide you are using. I have found a number of bad carbide tools.

 

[jboger]

I don't want to start a new thread. I just got a waller carbide graver and the paste to sharpen it. I've checked around on youtube and this site and so far have not found what I'm looking for.

Can I sharpen my Waller with a Crocker tool? I've used that for my other gravers but don't know if I can with the Waller. I bought the graver with the paste. I'd like to sharpen by hand. Do I sharpen the Waller as I do my other gravers with the crocker? What about the paste? Or do I need some other setup?

Really would appreciate some help with this.

John

 

[Chris Radek]

I would try smearing a bit of the paste on a piece of brass, and then using your Crocker tool just the same as on a stone.

 

[gmorse]

Hi John,

I think a piece of glass rather than brass would be more likely to produce a truly flat surface with the diamond paste and a sharpening jig.

Regards,

Graham

 

[Skutt50]

I use a diamond wetstone for my carbide gravers.

 

[jboger]

Thank you, everyone. This helps enormously. If I use the diamond paste on a piece of glass or brass, how much do I use? The amount supplied by my source (Timesavers in Az) is small. And it is expensive.

I will also look up a diamond whetstone. That strikes me as very interesting.

Skutt50: Can you make a recommendation, for example, what grit?

John

 

[DeweyC]

Thank you, everyone. This helps enormously. If I use the diamond paste on a piece of glass or brass, how much do I use? The amount supplied by my source (Timesavers in Az) is small. And it is expensive.

I will also look up a diamond whetstone. That strikes me as very interesting.

Skutt50: Can you make a recommendation, for example, what grit?

John

There is a very good system that you can find used on eBay. It is the GRS diamond sharpening system. 4 wheels and a guide. We used this in school in Switz. Another option is to buy a deckel or clone grinder and use tis diamond wheel. This will allow you to make solid carbide tools for your slide rest out of broken carbide mills.

In school we were allowed to make the mistake of using diamond film material on a glass to polish our gravers. Big mistake. Leaves a mirror finish but the minute flex ofthe film is enough to round over and destroy the cutting edges.

If using glass for the diamond paste, I would suggest getting a fairly large piece of plate glass and using very small areas. The diamond will create holllows where you are working.

Finally, you can use the DMT solid electroplated bench stones to prepare your gravers. These come in 3 grades and I would use all three. This will reduce the polishing required using the paste.

Whatever you do, keep the Crocker off the abrasive. It will wear down unnecessarily of course. With the bench stones, keep it to the side and raise it if needed with a block of steel.

 

[Skutt50]

Skutt50: Can you make a recommendation, for example, what grit?

Sorry but I don't know!

I mainly use a small (about 7,5x2,5cm.) diamond wetstone that is my favorite. It is a steel square with diamonds pressed in on one side. It was sold as a sharpener for fish hooks. When new if was rather course but over the years it has worn down to a much finder grit.

Unfortunately the shop that sold it does not have it in their asortment any more......

You would probably do fine with a medium or fine grit......

 

[jboger]

OK, I have enough input to move forward.

I gave up staffing quite a while ago but recently started again--or trying to. My normal steel gravers just wouldn't cut the mustard. And those staff removal punches that come with K&D staking sets should be outlawed. Anyway, I bought a Waller engraver with the hopes that it was pre-sharpened. It was, at least one side. What a pleasure to remove a staff. I riveted in a new staff, reassembled the balance, and the watch took off again.

But now I need to sharpen the Waller.

Thanks again.

John

 

[gmorse]

Hi John,

How fine a grade of diamond paste you need depends on what you intend to use the graver for, and also how blunt it is at the moment. If it's in a poor state you need to restore the cutting angle, so begin with a coarser paste, say 30 micron (600 grit), and then progress via 12 micron down to 5, 3 or even 1 micron for the finishing; the finer the finish on the graver, the finer the finish on the staff and the less polishing you will have to do. It also helps if your finishing strokes run parallel to the edge you intend to cut with.

If you're only using the graver to rough out the work, you won't need to give it such a fine finish.

Finally, you can use the DMT solid electroplated bench stones to prepare your gravers. These come in 3 grades and I would use all three. This will reduce the polishing required using the paste.

These are very good and the credit card sized ones are probably big enough for your needs, (and they aren't nearly as expensive as the larger bench stones).

Regards,

Graham

 

[jboger]

Graham:

Very useful information.

Right now, I'm thinking rough work, like removing a bad staff. What prompted me to write my query is a job I have at hand. I've fitted a new staff but can't put the roller table back on as the hole is too small for the staff. I'd rather modify the staff than enlarge the hole on the roller table. That side of the carbide graver won't cut the staff, whereas the other side easily cut the rivet when I removed the staff from the balance. This is my second staffing job with the Waller and the first time I am using this one cutting edge

I'm leaning towards a diamond whetstone. Seems like it might be cheaper that the diamond paste, that is, in the long run.

By the way, I understand microns but don't know the relation between microns and grit. Thirty microns correspond to 600 grit. Does 15 microns, for example, correspond to 300 grit or 900 grit. I'm inclined to think the latter.

John

 

[gmorse]

Hi John,

By the way, I understand microns but don't know the relation between microns and grit. Thirty microns correspond to 600 grit. Does 15 microns, for example, correspond to 300 grit or 900 grit. I'm inclined to think the latter.

The smaller the mesh and micron values, the larger the grit number, see attached chart.

Regards,

Graham

 

[karlmansson]

Sorry but I don't know!

I mainly use a small (about 7,5x2,5cm.) diamond wetstone that is my favorite. It is a steel square with diamonds pressed in on one side. It was sold as a sharpener for fish hooks. When new if was rather course but over the years it has worn down to a much finder grit.

Unfortunately the shop that sold it does not have it in their asortment any more......

You would probably do fine with a medium or fine grit......

I think I have the exact same one, Biltema right?

 

[karlmansson]

One thing to bear in mind is that as carbide is brittle, the pressure normally required to hold the face flat against the stone on a HSS graver can lead to edge fracturing when run free hand or with a sharpening jig over a coarse diamond hone. At least I have found that to be the case. Rather go for light pressure and high surface speed when sharpening carbide. So either light, long strokes with a very stable jig manually or against a high speed diamond wheel as suggested by Dewey. You can certainly hone carbide at lower speeds as well but then use a finer grit and keep to less acute edges. Slow speed grinders for carbide tipped scrapers seem to be popular for instance.

Regards
Karl

 

[DeweyC]

One thing to bear in mind is that as carbide is brittle, the pressure normally required to hold the face flat against the stone on a HSS graver can lead to edge fracturing when run free hand or with a sharpening jig over a coarse diamond hone. At least I have found that to be the case. Rather go for light pressure and high surface speed when sharpening carbide. So either light, long strokes with a very stable jig manually or against a high speed diamond wheel as suggested by Dewey. You can certainly hone carbide at lower speeds as well but then use a finer grit and keep to less acute edges. Slow speed grinders for carbide tipped scrapers seem to be popular for instance.

Regards
Karl

Also there are a number of grades of carbide. In my experience, the Waller grade is not very useful. I use only micrograin carbide. The grade sold by Eternal Tools also used to be very good. But I now "roll my own".

 

[karlmansson]

Also there are a number of grades of carbide. In my experience, the Waller grade is not very useful. I use only micrograin carbide. The grade sold by Eternal Tools also used to be very good. But I now "roll my own".

You make your own carbide...?

 

[Skutt50]

I think I have the exact same one, Biltema right?

Biltema it is. Article number 19-2162 but not sold anymore.......

 

[Skutt50]

You make your own carbide...?

I have used some broken carbide drills. By shaping what is left of the drill on a diamond wetstone I get some very small but also very effective carbide gravers. They cut even the hardest steel like butter.....

 

[DeweyC]

You make your own carbide...?

Karl,

I make gravers and cutters out of broken carbide endmill shanks (6mm). I grind them square and then make whatever cutter I need. I use the remaining round section to mount the cutters in either a standard sized graver handle (held with grub screw) or in standardized square tool bit holders for my lathes (same size bit holder fits in the tool holders of my 102 and WW).

This way I only ever have one library of cutters for either lathe or graver handles.

This can be done easily with either an SO style grinder (Deckel, Alexander or Chinese clone) or I happened to luck into an Agathon clone (Star). I like the Agathon since it it has oil flow which keeps the dust down.

 

[karlmansson]

Karl,

I make gravers and cutters out of broken carbide endmill shanks (6mm). I grind them square and then make whatever cutter I need. I use the remaining round section to mount the cutters in either a standard sized graver handle (held with grub screw) or in standardized square tool bit holders for my lathes (same size bit holder fits in the tool holders of my 102 and WW).

This way I only ever have one library of cutters for either lathe or graver handles.

This can be done easily with either an SO style grinder (Deckel, Alexander or Chinese clone) or I happened to luck into an Agathon clone (Star). I like the Agathon since it it has oil flow which keeps the dust down.

I guessed that this would be the case, I too save any broken carbide tooling I happen to produce.

It doesn’t really say anything about the grade of carbide though?

 

[DeweyC]

I guessed that this would be the case, I too save any broken carbide tooling I happen to produce.

It doesn’t really say anything about the grade of carbide though?

Karl,

It depends on what you buy. I only use Micorgrain stuff. Kyocera stuff is very good; but you have to make sure the shanks are carbide.

 

[jboger]

Progress report. But first thanks to everyone for their input and suggestions.

I had bought a Waller carbide graver maybe a month ago and the diamond paste sold with it (expensive). Then a few days ago I discovered that I already had a Waller graver, an old one that I must have bought used a long time ago. Anyway, I decided to sharpen that one with the paste rather than my new one. The carbide tip was in bad shape. The diamond paste is cutting OK, but it is still taking a while to get a flat surface--almost there but not quite. Need a break now and then. I'm probably wasteful of the paste as every now and then I need to check my progress. When I do so, I lose some paste despite my best effort. I used a piece of glass as my substrate. It is certainly being scored by this activity.

Question: Does this method of sharpening leave a burr on the cutting edge? I'm not feeling one, but perhaps it's still there? Is the fingernail test sufficient to determine if my graver is sharp enough? I'm no longer at the bottom of the learning curve, but I have not passed the inflection point by any means either (that's for anyone who might be a calculus fan out there).

I will invest in some diamond whetstones as I think this paste is far too expensive whether I'm wasteful of it or not.

John

 

[gmorse]

Hi John,

If the graver is in rough shape, please re-read my post #16. If you need several grades of diamond paste, as it seems you do, then you can buy it in small syringes from various suppliers; I doubt if there's anything particularly special about the Waller stuff.

Steel gravers produce a burr because they're soft enough to 'roll' away from the stone very slightly, whereas sharpening carbide shouldn't leave a burr, it's just too hard.

Regards,

Graham

 

[everydaycats]

Hi John,

I think a piece of glass rather than brass would be more likely to produce a truly flat surface with the diamond paste and a sharpening jig.

Regards,

Graham

Ditto this. Glass works well with DP.

 

[jboger]

What a pleasure to be able to finally replace a staff. I finished sharpening the Waller. The task at hand was to take down the lower portion of a staff to fit the roller table. I do not think the roller table is original. As for the new staff, all the pivots are fine as it came, the hairspring fits snugly, and the overall length is right--no work was done on these. But the roller table would not fit. I am sure if I had tried to force fit the roller table, I would have split it. So I took the staff down. It is now snugly seated on the staff. I intend to abandon that diamond paste and buy those whetstones. Any suggestions?

 

[DeweyC]

What a pleasure to be able to finally replace a staff. I finished sharpening the Waller. The task at hand was to take down the lower portion of a staff to fit the roller table. I do not think the roller table is original. As for the new staff, all the pivots are fine as it came, the hairspring fits snugly, and the overall length is right--no work was done on these. But the roller table would not fit. I am sure if I had tried to force fit the roller table, I would have split it. So I took the staff down. It is now snugly seated on the staff. I intend to abandon that diamond paste and buy those whetstones. Any suggestions?

DMT, solid surface not perforated. Expensive but will still be in your stuff when it gets sold.

 

[jboger]

Well, I must needs invest in those whetstones regardless of their price. Once you go carbide, you never go back! I checked. I saw a pack of three (different grits), 8-inches long, for something like $200.

 

[gmorse]

Hi John,

The smaller credit-card sized plates from DMT would do the job quite adequately for a lot less money.

Regards,

Graham

 

[jboger]

Now ordered.

I'm assuming these whetstones may also be used for regular steel gravers, no? Any lubricant needed, like an oil?

 

[gmorse]

Hi John,

I'm assuming these whetstones may also be used for regular steel gravers, no? Any lubricant needed, like an oil?

Yes, you can use them on HSS or carbon steel gravers as well as on carbide, but if you want a really fine finish on the steel ones, do the final polish on a good Arkansas stone with the appropriate oil. I don't use a lubricant on carbide gravers, but I do wash the DMTs occasionally to keep them cutting.

Regards,

Graham

 

[jboger]

With many thanks to those who advised me, and for those who may be new to sharpening carbide gravers, here are two pictures of my whetstones, gravers, and Crocker jig. For about $37 (which includes shipping) I was able to buy three whetstones--fine, medium, and coarse--and do in a few minutes what seemed to take an interminable amount of time with diamond paste. One advantage of these whetstones is that you can monitor your progress without loss of the diamond paste, which obscures your work.

 

[MrRoundel]

Great thread. Thanks, just what I was looking for. Cheers.

 

[MrRoundel]

I got my set of the credit card sized DMT sharpening plates. They seem to work great, making quick work of getting a couple of Waller/Grobet tips in shape, as well as a Barkus I have. One question though: Is it necessary to go beyond the green "Extra fine" diamond grit? Do I need to rid the tips of feathered (?) edges the way you drag tool steel and HSS over a stone? I don't feel or see any extra material on the edges. Many thanks. Cheers.

 

[gmorse]

Hi MrRoundel,

One question though: Is it necessary to go beyond the green "Extra fine" diamond grit? Do I need to rid the tips of feathered (?) edges the way you drag tool steel and HSS over a stone? I don't feel or see any extra material on the edges.

Not in my experience, the carbide is very hard and doesn't form any edge burrs the way ordinary tool steels do. It does help to finish the edges off along rather than across them.

Regards,

Graham

 

[MrRoundel]

Thanks, Graham! That's the way it seemed. Cheers.