[OP]
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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.Originally Posted by john brenton
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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.
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Larry, Would you please expand on this;
Thanks
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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.
Last edited by george wilson; 05-12-2011 at 8:56 PM.
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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.
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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.
Last edited by george wilson; 05-12-2011 at 10:42 PM.
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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.
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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.
Last edited by george wilson; 05-12-2011 at 4:14 PM.
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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
Wheels for this grinder run about $160 each.
Member
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.
Last edited by george wilson; 05-12-2011 at 9:04 PM.
Member
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.
Last edited by Larry Williams; 05-12-2011 at 10:08 PM. Reason: clairity
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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 !
Member
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
Last edited by Salem Ganzhorn; 05-13-2011 at 12:41 AM.
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