More sharpening (some specific questions)

[Shaun Mahood]

I was hoping to figure this out without adding to the crazy amount of sharpening questions, but 2 books and the internet haven't quite solved everything. I'm using scary sharp and a honing guide and can get things as sharp as I want, but I want to change some things.

Here are the things I'm looking for
- no power grinder (which means no hollow ground)
- no soaking of stones
- no sandpaper
- gradually transitioning to freehand honing
- all O1 steel

I'm leaning towards adapting something like George Wilson's method (DMT and spyderco) or Larry Williams' method(DMT and oil stones), both with a strop at the end. I really want something with as little mess as possible, and to not have to worry about things going out of flat. The spyderco sound wonderful but I'm not sure if I will need an oilstone as well.

Does anyone have any advice about freehand without the hollow grind?
Can I use the DMT for grinding, or will that ruin it?
Would a Spyderco medium work for all my grinding?

If these have been answered before I apologize, I have some trouble deciding what I want to do when there is no one right answer.

[Stuart Tierney]

Very quickly since I'm swimming in gear here but;


- no soaking of stones

I can't help you, and good luck.

Not if you're looking to replace a powered grinder with something as fast as a power grinder. There's only one stone that I'm aware of that approaches the speed of a grinder, and it needs soaking.

Sorry.


Stu.

[Shaun Mahood]

Stu, what stone would you recommend? I'm open to soaking for the grinding portion.

[Norman Hitt]

"IF" you just want to eliminate power, but would still like a hollow grind, there IS a way to do it. Buy an old Hand cranked grinder, and mount it on the end of a bench top that sticks out past the legs about a foot, like a Roubo. Next, remove the crank handle and install a small bicycle chain sprocket. Now make a frame to attach a Bicycle's Pedals, drive sprocket and bearing housing to the legs, and install a Bicycle chain on both sprockets. You will probably need to make a blade guide attachment in front of the hand grinder for good angle control while grinding and then you just pull up a stool and pedal away and grind tools to your heart's content.

YOu could aLso modify a stationary bicycle or exercise bike to do the same thing by mounting the grinder to an attachment fitted into the part where the handlebars mount tin the frame and then bring the chain up to it from the pedal sprocket.

Now you can be a REAL Neander, and get your exercise at the same time.:D (maybe you could convince the LOML to exercise there too, and of course, grind a tool or two while she's at it.;):D

[David Weaver]

If you are using O1, why do you want to omit a power grinder? O1 grinds really easily and quickly, and it takes much longer and much more effort to use paper or stones to do it. It might be a couple of minutes instead of one on a fast stone or coarse sandpaper, but you have other issues with those.

I would use george's method over oilstones for two reasons:
1) oilstones *do* need to be flattened (well, they don't need to be, but unless you're going to spend extra time honing aimed at keeping the stone flat, you'll need to flatten them)
2) the groove that a ceramic stone leaves is much more appropriate to follow diamonds unless you start very coarse with the oilstones

Medium stones of any type will not be suitable for grinding. Like norman says, maybe a hand crank grinder would help, but you want the hollow grind - it will cut down your time and improve your results considerably. You can freehand anything with a coarse stone by freehand grinding with the coarse stone, and then increasing the angle slightly with each finer stone, but it takes more time and more stone maintenance than a hollow grind.

[john brenton]

It's entirely possible to freehand without a hollow grind, but you most likely won't end up with a flat bevel. When you go to polish the bevel edge you'll see that there is most likely a little belly. The best thing would be a honing jig.

Soaking doesn't take that long. I keep water in a spray bottle, and when it's time to sharpen I just dump a little water from it in a discarded plastic dish and let the stone soak for a few minute. The Norton's aren't as bad as the King stones....you could throw a King stone in a swimming pool and I think the water level would go down by half. Those things take forever. But not the Nortons...and especially not the higher grits.

And a grinder...well...after you see how much wear you are putting on an $80 stone then you might change your mind!



Does anyone have any advice about freehand without the hollow grind?

[jamie shard]

I just wanted to add: grinding is fun! ...and combo grinder/belt sanders are really fun!

[John Tallyn]

If you are willing to do a little soaking, a 200 grit king stone is about the fastest way I know of to take a lot of steel off, not as fast as a power grinder, but still takes a fair amount of steel off in a shorter amount of time. There maybe some folks out there that can discuss diamond stones, but I've never used one, so not sure how fast they work. Myself, I'm into a 1" belt sander, then I use sandpaper on glass for the rest. Occasionally I see large foot cranked stones for sale around here at some of the ranch/estate sales, that's how my dad taught me to sharpen, but I think it was as much for punishments sake as anything else.
John

[Andrew Pitonyak]

As already stated, when going free hand, watch out for rounding the blade. I recently purchased a #6 with an OK sharp blade, but, the front of the blade had quite a bit of an arc to it (watch the blade roll if you try to free hand it with this blade) and the back has a pretty large back bevel.

I dropped the blade onto my Tormek so now the blade has a hollow grind to it. The back heavy bevel is still there, and there is still a small nick in the blade. The blade is, however, now sufficiently sharp for testing.

I own water stones and I own DMT plates (extra course, fine, extra fine, and an 8000 mesh polishing stone). The DMT plates cut pretty fast, but, I find that the super fine diamond plate leaves course scratches. The rumor is that this will wear down, but, it means that I don't really use it as it is intended, and I perform final polishing on something else.

You do not list your location, if you live in the area, you should wander by and we can have a sharpening party (not that I am an expert, but I do have things you can try).

[george wilson]

Diamond stones do leave a coarse surface,but they cut very rapidly to get the initial sharpening done,which is to eliminate the rounded cutting edge,and possible little nicks from use on wood. The black,then fine white ceramic stones make a quick job of making a smooth micro bevel at the cutting edge. If you get ceramic stones,get the super fine white,as it has already been flattened and smoothed. I had to hone fuzz off my white Spyderco with a diamond stone,and make it flatter. This was done under the sink faucet. You may want to save yourself this labor,and the wear on your diamond stone.

I don't think a frequent user could produce any wear on a ceramic stone in 100 years.

[Shaun Mahood]

Thanks for all the replies, I really appreciate the advice.

I would love to have a foot powered grinder at some point, but I don't have much room in my shop and want to set up the smallest sharpening station I can get away with. This is kind of step 2 of my sharpening journey - step 3 may end up getting a grinder.

Definitely going to go with the spyderco stones, and see how DMT works for the initial sharpening.

We'll see how the freehand honing goes - I do like how well the honing guide works, but the idea of freehand honing kind of taps into the part of my brain that gravitates towards hand tools in the first place.

[john brenton]

I started out trying to keep things as simple and neander as possible, not just for some weird innate desire, but also because of money issues...and the time I've spent doing everything by hand is invaluable.

But, they don't call it "the hard way" for nothing, and eventually you'll want to speed up the process.
I'm not sure how far along you are, but I'm pretty sure that fairly soon the idea of a garage full of power equipment won't sound like such a bad idea. There was a time where I'd look at a finished project and say "Look at me, I did everything by hand!", but now I say "dang, I could have made three of those if I wasn't doing all this by hand." This is especially true for simple furniture that really gains no value by being hand made. Perhaps hand crafting a 17th century reproduction carved writing desk or something would get my socks rolling up and down, but not a relatively simple coffee table or cabinet.

Anwyho, the honing guide is a good thing, not just a "convenience", and it's something that I was not interested in either. It came with a set of stones on ebay for dirt cheap and I gave it a go. I can still freehand hone, but choose not to. That solid edge and the ability to make accurate secondary bevels saves time in the long run.

I didn't know about forums like this, or read any magazines when I was starting, so I was just playing it by ear..picking up tools at the flea market and having no idea what to do with them. If you don't have your arsenal already set up, I would see what people here have as far as tools and sharpening, because they are all GENERALLY frugal people who share our love of hand tools and working with them (some guys don't seem so frugal (I'm jealous), but in the end I guess it all works out the same). Chances are that if people here have them it's not some "modern frivolity", but something that works and makes work easier/better.

[Larry Williams]

Shaun,
There are hand cranked grinders available and they're capable of doing almost everything you need for bench planes and chisels. Then get a medium India stone and a good hard Arkansas translucent stone. I suggest a coarse diamond stone to maintain your oil stones but don't use it on steel. The medium India will quickly work problem areas and the hard Arkansas is the equivalent of a 6000 grit water stone and , when properly maintained, cuts faster than the 6000 grit water stone--fast enough that you don't need to go through a series of stones. Your stones will easily fit into an area of a square foot while requiring significantly less maintenance than water stones. All the oil stones require is appropriate dressing before each use to stay flat and fast cutting.

[john brenton]

not to mention all the other stuff you'll be using that grinder for: fixing damaged threads, shaping different objects, taking burrs off of tools or other household stuff, etc.


I just wanted to add: grinding is fun! ...and combo grinder/belt sanders are really fun!

[george wilson]

Many thousands of woodworkers use diamond stones on steel. I have since the 70's. What's the problem? An Arkansas stone is much softer than a ceramic stone. I have easily ground damaged Arkansas slip stones to special shapes on my belt grinder with ceramic belts. You can't cut a ceramic stone like that,though. It won't need flattening,ever. India stones are good stones,but pretty out dated. I used them many years ago.

If you mean don't use a coarse diamond stone on your steel,I use a 325 and a 600 grit diamond stone on steel.

[Shaun Mahood]

I started out trying to keep things as simple and neander as possible, not just for some weird innate desire, but also because of money issues...and the time I've spent doing everything by hand is invaluable.


This is basically the stage I'm at - I've done enough to know that I want to stick with it, and have a list of projects to last me quite a long time, so I'm starting to gradually add more tools and learn new skills. This site has been an amazing resource, and the discussions on here are definitely helping to prioritize things for me. My goal is to eventually be able to build classical guitars, which generally don't seem to benefit much from powered equipment.

[george wilson]

If you buy already thicknessed wood,you can hand plane down the 1/4" thick tops by hand. They can be had made to 1/10" thick,but I like to determine thickness myself. That and wood selection are major issues in tonality.

I found that I used my 14" bandsaw and drill press the most back in the 1960's. I'd have loved to have had the Delta 18-36" open side thickness sander I have now.

[john brenton]

Not sure if you were the poster I sent this link to the other day, but in case you missed it:

http://mysite.ncnetwork.net/resr7g3w//

If this guy ever takes his site down I'm going to be pissed that I didn't print out the pages and keep a book. It's a wonderful site.


This is basically the stage I'm at - I've done enough to know that I want to stick with it, and have a list of projects to last me quite a long time, so I'm starting to gradually add more tools and learn new skills. This site has been an amazing resource, and the discussions on here are definitely helping to prioritize things for me. My goal is to eventually be able to build classical guitars, which generally don't seem to benefit much from powered equipment.

[Shaun Mahood]

Not sure if you were the poster I sent this link to the other day, but in case you missed it:

http://mysite.ncnetwork.net/resr7g3w//

If this guy ever takes his site down I'm going to be pissed that I didn't print out the pages and keep a book. It's a wonderful site.

John, wasn't me but I have looked at that site a few times. The best resource I've found (by far) is the luthier's forum on Delcamp - pretty sure that's how I ended up finding this forum, and everything else useful. If you've never been there be prepared to waste a lot of time reading through their posts.

[george wilson]

I am not one of those who enjoy turning a crank with 1 hand and holding a blade with the other. When I was young,every old light house we lived on had those hand cranked grinders. I hated to use them.Electric grinders can be had so cheap these days,for an import,I just can't see the point of getting a hand cranked grinder that will probably cost just as much,and need cleaning up,restoration,etc..

You don't have to spend $300.00 on a Baldor to have a serviceable grinder. I have had an import,among others,since the 70's,and it still works fine. My other 2 bench grinders are old Sears flat front grinders from the 1960's. I actually like them well enough that I haven't needed to upgrade them. Their flat front motors allow grinding drawknives without hitting the motor. They also have double jointed tool rests. you can turn them completely straight out,and catch your chisels or gouges in the crook of their tangs. This allows you to place them at exactly the same angle on the wheels every time,so you get a neat,un faceted bevel. Or,you can put a little C clamp on a blade to catch on the tool rests to get accurate repeat angles on plane irons.

Beyond them,anything else can be ground on my Wilton square wheel belt grinder. They are not pretty,but they are the most versatile grinder out there for making knives from scratch. I enjoy the precision that can be achieved freehand in grinding things like Bowie knives on them. Since the belt grinder cuts so much faster and cooler,it is really my most used grinder. I got one of those Jet wet wheel Tormach(sp?) grinders cheap,new in the box for $100.00 IIRC,but the stupid thing keeps breaking down. the little press on contacts in the circuit board are made from beer can gauge aluminum,LITERALLY,and they crack. Next time I get around to removing the circuit board,I'm going to solder every one of them,not just the broken one.

Those familiar with my work know that I do much work by hand that cannot be done by machine. No offense to those who want to get crank grinders,but there is just nothing "noble",or whatever,that I can see about using a crank grinder. It's not the same as hand carving or other personal skill driven work. It is just plain work. We had to put up with those forever in Williamsburg,the large sandstone wheel types. It took forever to sharpen a plain,laminated old style plane iron on one of them. The only hard steel part on those was the thin layer of hardened steel,and it still took forever.

This isn't meant to be a rant,though it seems to read like one. I guess I just like to save my energy for useful work before I run out of steam(which is getting easier to run out of.)

[Shaun Mahood]

George, thanks for all your help and input with this. It's sometimes tough to tell where advice is coming from - it's great to get advice that is time tested and I really appreciate it.

[george wilson]

If I am only making a theory,I say so. What I say is usually based upon actual experiences. I'll be the first to admit that I am as bad as anyone to use out dated methods and do everything the hard way. Being in a museum situation from 1970 to 1986,I was forced to use old methods. Most of the time,I didn't mind,as I used them anyway. The 2 things about using 18th.C. tools I liked least were methods of drilling holes(except I like using a pump drill),and grinding. Had no problem with wooden planes and still use them. No problem with hide glue. It is the best thing in many cases,and is time proven,and reversible. No problem with chisels and gouges. They haven't changed that much. Nor has sawing. A lot of hand tool work hasn't changed that much.

[Larry Williams]

Many thousands of woodworkers use diamond stones on steel. I have since the 70's. What's the problem? An Arkansas stone is much softer than a ceramic stone. I have easily ground damaged Arkansas slip stones to special shapes on my belt grinder with ceramic belts. You can't cut a ceramic stone like that,though. It won't need flattening,ever. India stones are good stones,but pretty out dated. I used them many years ago.

If you mean don't use a coarse diamond stone on your steel,I use a 325 and a 600 grit diamond stone on steel.

George,

I've written about this a number of times. This is from one of my more recent posts about it:

"I once had a number of plane irons to do that needed accurate clearance angles ground to their sides. I decided to use the diamond grinder and ordered in a new set of grinding wheels for it. In a very few minutes and with little progress I had worn out a pretty expensive grinding wheel. I called the manufacturer and spoke to their tech rep.

He explained that diamond grinding wheels shouldn't be used to grind ferrous metals. They're designed for things that generate a granular grinding swarf like carbide, stone or glass. The diamonds are mounted in a nickel matrix that's intended to slowly wear away as the layered structure of the diamonds fail. Each diamond is a series of brittle layers and, as their cutting edges wear, they fracture and spall away exposing another layer with fresh edges. Steel and other ferrous metals have a stringy shaving-like swarf that quickly wears the nickel, undermining and releasing the diamonds. I believe some of the diamond stones available use a resin matrix but I doubt these are more resistant to the metal shavings in the swarf of ferrous metals.


This is why all the texts on machine shop practice say to grind away the steel backing on carbide tipped tool bits with a regular grinder before grinding the carbide with a diamond grinder. It also explains why I wore out the first extra coarse diamond stone I bought so quickly. However, the extra coarse stones we use for dressing oil stones seem to last and last."


A link to the osculating diamond grinder we use:
http://tinyurl.com/26pgkud (http://tinyurl.com/26pgkudWheels)
Wheels for this grinder run about $160 each.

[george wilson]

I have written also: grinders with diamond wheels for use on steel run at about 200 RPM. I had one at work(which was over $2000.00),and was lucky to find a used one for home very cheap,and it is a floor model. Wheels are about $275.00,so you can bet I'm not abusing it!!

The rep did not steer you in the right direction. What he said was true for a fast grinder only.

I understood you were speaking of the diamond bench stones,though. There is no harm in using them on steel. That is what they are primarily made for. Google diamond bench stones for steel. What kills diamond on wheels is speed,where the diamond builds up enough friction that the carbon migrates into the steel. They are,as you said,for carbide.

I also have a high speed carbide grinder that runs 3450 RPM,and is ONLY for carbide in my shop.

It is easy to Google that it is true that the carbon in diamonds goes into steel if used at high speeds.. I showed that to Pam last month. There are diamond wheel manufacturer's statements you can read on the internet.

I have had my diamond stones at home for several years,at least 12,maybe longer. At the shop,we had one of the very early diamond bench stones,which,unlike today's stones,was mounted on a solid block of acrylic,instead of on a cheaper cast plastic base we were given the stone in the 1970's by a donor. That's how old it is,and we were still using it when I retired,on steel tools. These are,of course,the common nickel matrix stones now also available with a steel plate.

Please google it for yourself if in doubt. You are denying yourself a quick and easier way to start an edge,or get rid of small nicks if you don't use a diamond bench stone.

Google accu-finish. It is a low speed horizontal/vertical diamond grinder. It mentions HSS (machinists don't usually use plain carbon steel),as well as ceramics and carbide to be sharpened on it. Mine is a Sunnen.

I know you have had disagreements with Ron about carbon migration. It is not necessary to debate this subject,as anyone who cares to can google around and see that diamond carbon does migrate into steel(at high speed),and slow speed grinders with diamond wheels can grind steel. Your rep did not supply you with complete enough info about your diamond options.

[Chris Vandiver]

Larry, Would you please expand on this;



All the oil stones require is appropriate dressing before each use to stay flat and fast cutting.

Thanks

[george wilson]

I have not found it necessary to flatten or dress an India stone before each use. Maybe after months of use.They are aluminum oxide,and a pretty dense,hard stone. I used them all the time in the 60's,and still have some in my bench . You can clean them if they get full of crud,but that can be done with a stiff brush and powdered cleanser and water without wearing them out by frequent flattening.

[Larry Williams]

Chris,
Oil stones, both novaculite (Arkansas) and aluminum oxide (India), dull with use. In that regard they're like grinding wheels. Light dressing with a diamond stone refreshes the cutting surface, just like dressing a grinding wheel. Careful application of the diamond stone when dressing oil stones will maintain a flat face on the stone. It doesn't take a lot of dressing and leave the slurry on the stone for use. Try it, you'll be amazed at how fast India and Arkansas stones cut.

[Larry Williams]

The rep did not steer you in the right direction. What he said was true for a fast grinder only.

... What kills diamond on wheels is speed,where the diamond builds up enough friction that the carbon migrates into the steel....

George,
The grinder we have is very low speed, maybe even less than 200 rpm.

Diamonds migrating into steel is a wives' tale. Diamonds, like coal, are pure carbon and they'll burn just like coal. Yes carbon does migrate through steel but only above critical temperature which is is in the 1400°+ F range. Diamonds auto ignite at 700° C or 1295° F, long before steel reaches critical temperature. Those who think they're observing diamonds migrating into steel don't seem to realize the diamonds burned up and turned to CO and CO2. The diamonds go away but they go into the air, not the steel.

[george wilson]

True,I would dress an India stone to sharpen it,but not to flatten it. Scrubbing out the crud helps,too.

There are manufacturers of diamond wheels that specifically state that the carbon migrates into steel. I urge you to do some more research if you think this is a wive's tale. When I was discussing this with Pam,I googled diamond dissolving into hss. I got an article put out by SP3 Diamond Tool Makers. It specifically stated that microscopic examination proved that diamond carbon does migrate into steel. Now,of course I can't find that article. You have my word that this is exactly what was said,though.

The Accufinish grinder also mentions that it is for HSS as well as carbide,ceramics,etc.. That CAN be found.

This is all I can tell you.The subject has also been discussed at great length on the Practical Machinist's Forum,where there is an agreement that diamond carbon does go into steel. I will continue to get the ease and benefits of using diamonds on steel. You will just keep over working yourself doing it the hard way,and that is fine,too. To each his own. I haven't worn out my diamond bench stones yet after many years.

Technique might have some bearing on wearing out diamonds. You must not bear down too hard on them.

[Larry Williams]

Some how I messed up the link to the grinder. Here's the right one:
http://tinyurl.com/26pgkud

If diamonds migrate into steel, it would absolutely have to be on the atomic level. The one distinct feature of a diamond is its crystalline structure. Remove a carbon atom from a diamond and it's just a carbon atom. Are you saying, George, that someone can tell if a carbon atom came from a diamond? How do they do that? It's no longer crystalline, as a single atom it can't be.

HSS grinds much like carbide. Surely you've noticed the difference between the spark patterns when grinding HSS vs. high carbon steel. I'd be comfortable grinding HSS with our diamond grinder but I know what happens when one grinds high carbon steel with it. Want to buy an expensive diamond grinding wheel with few diamonds and little nickel left? I have one I can spare.

Trust simple physics, George. Diamonds burn up before steel reaches critical temperature. Those that think diamonds migrate into steel inhale a lot more diamond than migrates into the steel.

[Salem Ganzhorn]

I am happy with the following for speed, lack of mess and relative expense:
1) Grinder with frillable wheels and nice platform like the Wolverine jig. I have the woodcraft 8". I use it for both turning tools and chisel's/panes. I would prefer a separate 6" grinder to give more of a hollow grind for chisels etc but that will have to wait.
2) Medium Sypderco ceramic stone: I use this to remove light nicks and to flatten the backs of irons. I also sometimes use 100 grit sandpaper on MDF clamped to my jointer for flattening the backs of irons.
3) Fine Sypderco ceramic stone (the bigger one): I use this for honing.

I have a Veritas MkII honing jig but I rarely use it. The hollow grind makes it pretty easy to free hand hone. And very often I can go from the wheel straight to the Spyderco fine stone with nothing in between.

I started out with sandpaper on granite using a jig. This works but was painfully slow. I have no desire to go back to a flat bevel. It is just too much metal to work.

From there I went to Oil Stones to move away from the sandpaper and to learn to free hand sharpen. At first they seemed to cut pretty well but after a while they became too slow. But this experience did teach me that not all of my tools need to be atom splitting sharp and it is a waste of time to try. It is better to have all your tools pretty sharp all the time then to have a couple that are amazingly sharp sometimes.

Eventually I started turning and picked up a grinder for lathe tools. I tried it out on my plane irons and chisels and then all of a sudden sharpening was much, much easier. Having a hollow grind is great!

Finally I added the Sypderco stones. They cut fast, haven't clogged/slowed down on me yet and they are not messy.

Good luck with your quest but don't rule out a grinder!
Salem

[Jim Koepke]

I wonder if this is the paragraph George was referring to in his post…


Diamond is unaffected by almost every other chemical or compound in nature. One exception is hot iron. The carbon atoms in diamond will dissolve into the iron, quickly eroding the diamond surface. Iron wheels are used for polishing natural diamond.

http://www.sp3inc.com/FAQ.htm

jtk

[george wilson]

Invariably,it seems, when someone mentions the laws of physics,they do not understand these laws well enough. Jim's article above mentions diamonds dissolving into hot iron. With the tiny bearing points that the diamonds on a FAST rotating wheel have upon iron,it would be perfectly feasible for localized heat from friction to be generated against the microscopic diamond contact points and the steel,and cause carbon migration. apparently SP3 has observed the migration of carbon through microscopic examination of control samples. You can even see individual atoms with an electron microscope.

When tapping steel with a hand tap,sometimes a popping sound and sticking when trying to reverse the tap is noticed. This is a common experience to anyone who has tapped threads in steel. What has happened is the tiny cutting contact points on the tap have pressure welded to the steel. I have even had trouble convincing blacksmiths that this is what happens,but it is well known to professional machinists who have scientific knowledge of their work,and not just home brewed ideas. The gunsmiths in Williamsburg always have trouble with iron pressure welding to their rifling cutter,which has a single tooth. They know pressure welding very well. These phenomena illustrate the incredible pressure and heat that can be generated upon tiny areas of contact,even at hand tool speeds. Gentleness is the needed rule. Gentleness and slow speed are the factors to success.

I have a friend at NASA who is now specializing in welding sheets of metal by friction of a rotating rod of steel. There are some advantages to the technique that they are investigating.

I have already mentioned that gentle pressure only should be applied to a diamond stone. This is both to avoid dislodging the diamonds,and to prevent migration. This is why MY stones have not worn right out,not even stones from the 1970's.

Experienced(experienced is the word here) machinists all agree that even HSS should never be ground on a fast wheel. Regardless of other additives,HSS still has an IRON MATRIX.

I have been machining since 1959,and reading studying,and conversing with professional machinists regularly since. Professional machinists on The Practical Machinist's Forum have discussed this issue to great length. They agree that carbon migration is a fact. Do you follow this group? I do not know how long you have been machining,or what the extent of your experience is.

[Larry Williams]

Think about it, Jim. One of the challenges of heat treating in a normal atmosphere is keeping the carbon in the steel when one reaches critical temperature. Even the carbon in the steel wants to migrate to the surface and oxidize. Are the carbon atoms in a diamond different in some way to where they want to ignore the tendency to oxidize and go the opposite direction and into the steel? Carbon fuels most of this planet and diamonds are just another form of carbon fuel. Get 'em hot and they oxidize, just like any other carbon.

[george wilson]

Since you seem to just ignore what I have written,I think I will stop debating with you,Larry. You are already convinced that you have encompassed all knowledge about machining,so I wish you well. Keep on making your nice planes. The woodworking community needs them.

[John Coloccia]

The correct answer is that nobody is sure exactly what the mechanism is, and it's still an active area of study. If someone wants to spend a little money, you can look up some current research on the subject, like here for instance:

http://www.informaworld.com/smpp/content~db=ai~content=a793156279~frm=abslink

My understanding is that there is more than one mechanism that results in diamond wearing on iron, but it's also my understanding that as George says, diamond tools chemically interacting with iron to form carbide is an established phenomena, though the precise mechanism is not fully understood. No need to argue this. There's a number of papers written on the subject that anyone can buy and read if they feel it's important enough.

[george wilson]

It does me no good to encourage googling about this subject,apparently. When diamond points are in intimate contact with iron,being rubbed against it at speed and under pressure,I cannot see it as much of a leap that carbon would smear into the metal. It is only a surface phenomena,and can be seen by microscopic examination,especially by those who make and study diamond tooling. Extra carbon deposition on the surface can be seen.

Thank you for putting that article up. I read it. Not sure if certain others may take the trouble. Personally,I am always curious,and wanting to learn. If you don't,you make no progress. There was a Master Blacksmith who just refused to learn anything that he did not stumble across on his own. For years he made plane irons that were severely dubbed over on their front faces."Every one I ever saw is like that",he said(always the same answer.) It took DECADES before he finally found some 18th.C. blades that were not
USED TO DEATH,and then he finally began to make them correctly. Those old irons were either dubbed by the users to increase their cutting angles,or they were carelessly flipped over on the stone to wipe the burrs off after sharpening until they got dubbed. After all,they were 200 years old,and that is a long,long time to be using them.

He refused to believe that taps got pressure welded,too. This is a very commonly known fact among those who have better educations in technology. The blacksmith's knowledge was only empirical. The gunsmith shop certainly dealt with it every time they rifled a barrel. They did not use any kind of modern,properly formulated cutting oil,which would have helped. That was their office,though,to work in the old style. They managed.

[Shaun Mahood]

I have already mentioned that gentle pressure only should be applied to a diamond stone. This is both to avoid dislodging the diamonds,and to prevent migration. This is why MY stones have not worn right out,not even stones from the 1970's.


George, is there an obvious way to know if you are putting too much pressure on a diamond stone?

[george wilson]

I can't really answer that,just use enough pressure to make it cut,but don't bear down hard. It is a skill development sort of thing. Think about not dislodging the diamonds.

[Terry Beadle]

You can buy a 200 grit stone from Highland Hardware for about $50. This stone will take the primary bevel down very quickly. You can also use a single cut file to remove steel more quickly. That said, if you are working A2 you may need to stick with just using the stone. If you are using O1 exclusively, then the stone or file will remove metal quickly for establishing a primary bevel. I recommend the 200 grit stone, flattened via 220 grit wet/dry on a flat surface ( I use granite but that's not a requirement. ).


A DMT xtracoarse/coarse is very valuable. I'd use the coarse to establish the primary bevel unless you have a good sized chip then the x-coarse will make short work of it. I also wouldn't worry too much about the diamond corseness leaving too deep a gouge pattern on the tool. These marks quickly come off and aren't very deep when using the coarse side of the DMT.

The extra-fine white ceramic recommended will take care of most polishing requirements excellently. Green rouge stropping will do the rest and is really optional for most wood working requirements.

I use water stones, which I leave in a big tupperware container soaking in water ( protected in winter ). There's no waiting for use. The higher grit stones, like the IceBear 10,000 grit just needs a quick spritz of water and about 20 seconds to soak, then it's away we go. Really puts a fine edge on a paring chisel but not required on a plane blade unless you have some very stubborn figured hardwood. Then it's worth while to give the plane blade a bit of extra edge prep.

It's not rocket science and it only takes one thing....practice. The effort to learn will pay off bit time on the finished products reflective surface and ease of finishing.

Enjoy the savings !