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Rick E
02-09-2016, 08:31 PM
Looking for some guidence and opinions on the best ways to sharpen wood cutting tools chisels draw knifes etc. oil stone vs wet stone? What do you like?

Thanks
Rick

GregH
02-09-2016, 09:03 PM
I've pretty much abandoned my oil & wet stones on favor of diamond "stones". A drop or two of WD-40 keeps them from clogging.

Gerarddm
02-09-2016, 09:21 PM
If I could afford diamond plates I would switch from 'scary sharp' sandpaper-on-glass.

htom
02-09-2016, 09:22 PM
Diamond stones. Lansky system. Wet/Dry sandpaper on 1/2" plate glass square.

Draketail
02-09-2016, 09:23 PM
DMT diamond stones through 1200 grit (green) followed by a leather strop charged with green stropping compound. Good enough I can shave when done. Others may swear they get better results with Japanese water stones. They may well, but the diamond stone/strop system works for me.

Get Leonard Lee's (of Lee Valley Tools) aptly named book "Sharpening" for the best explanation of the hows and whys of sharpening I have found.

Rob540
02-09-2016, 09:43 PM
I believe the material used in the cutting surface is probably less important than the method (or skill) you use to present the most suitable angle. Different stones/plates suit different folk and different tasks, but no matter which you use, getting the back of the blade flat and clean (preferably shiny) is a good start.

For the secondary bevel I have several ways of holding the blade true on the stone, and for some blades I like to hold 'freehand', but for most planes and chisels I still recommend one of those guides with a roller and adjustable positioning.

The diamond and the paper on glass methods are easier to keep really flat, but I still love Japanese waterstones because it feels good. The flatness of the secondary bevel is more important to me than it's angle (within limits; steeper for tougher work or harder timber, a bit lower for fine work etc), and the roller allows me to take the same exact bevel angle through different grades to the finish I want.
Having said all that, I always start a radical renovation with the back of the blade with W&D on glass just to get the big grit done and dusted.

http://middlething.blogspot.com

Tom Hoffman
02-10-2016, 01:23 AM
Once I get the edge close, I use an 8" X 1" wide soft loose cotton wheel on one side of my grinder. I use "White" Rouge on the wheel and polish away the wire edge and polish the bevel and part or all of the blade to a mirror finish if I am feeling fussy.

Doing it this way it is very hard to over heat the steel, just check your progress often. The wheel should not have any radial stitching around it except at the hole. It is very soft. At speed, it presents a firm surface that can be depressed as much as you want.

Peerie Maa
02-10-2016, 04:03 AM
I use diamond stones, with soapy water to avoid clogging. For stropping I use this system http://www.amazon.co.uk/Flexcut-PWS-Powerstrop-Leather-Wheels/dp/B000ZRW9SO.

When sharpening my draw knifes I clamp them to a block that goes in the vice. The top of the block is sloped at the bevel angle so that the knifes bevel is level when on the block and so is easy to sharpen with the stone.

Paul Pless
02-10-2016, 08:49 AM
If I could afford diamond plates I would switch from 'scary sharp' sandpaper-on-glass.in the long run. . .

Paul Pless
02-10-2016, 08:53 AM
The diamond and the paper on glass methods are easier to keep really flat, but I still love Japanese waterstones because it feels good. for hand sharpening, there is no faster stone than a japanese waterstone

BOI
02-10-2016, 09:51 AM
Agree with whoever said that holding your bevel angle and honing at the end are more important than what grinding surface/stone you use. For a tool with really big nicks in the cutting surface a power grinder speeds the removal of a large amount of metal. I'm a frugal person and will stick with something I have even if it is a bit suboptimal as long as it gets the job done.

I used to do a lot of woodcarving, and if anything needed presharpening because of nicks I used a power grinder (which was not mine and is half a continent away now), then a German artificial stone with a coarse and fine side that I inherited from my dad. The package gave no indication whether it was a water or oil stone. I used to use oil, now use hardware store honing fluid. The stone is getting a dimple in the middle, and once the edges are no longer flat either I need to use lapping grit to flatten it or invest in a new system. This is a disadvantage to stones, especially rather soft ones; you don't get that with sandpaper.

Before learning about Lee Valley Tools I had no idea that there are holders to keep the blade at the correct angle and have always held the tool by hand. As a result some of my bevels aren't totally flat, but slightly rounded. Still, by going from the coarse side of the stone to the fine side and a then a leather strop with hardware store green honing compound I got my chisels and Swiss army knives sharp enough to shave hair off my arm. I always kept around a piece of white pine wood and when the tool cleanly cut across the end grain without tearing I'd go to the strop. If it didn't I went back a step.

Jay Greer
02-10-2016, 11:07 AM
Different woods need to be cut with tools that are beveled to match the grain density of their structure. Soft woods such as pine or spruce require a flatter bevel than do harder woods. Mahogany is a medium density wood as is teak and need a steeper angle of attack from the edge of the tool. Where diamond plates are good for preliminary sharpening or restoration of a nicked blade, Japanese Water Stones are my preference for middle and final finishing stages of putting a keen edge on a tool. There are many forms of Japanese water stones, both synthetic and natural. Synthetic stones are best for softer steel and natural stones work well for harder or hand forged metals that are found in good quality Japanese chisels and plane blades. Natural stones come in a bewildering variety of textures and it is best to become aquainted with the synthetic water stones before switching over to natural ones as they can be very expensive. A final finish natural stone can approach 40,000 grit and will have a very high price as well. All finishing stones need to be scubbed with water and what is known as a "nagura stone" prior to final polishing. The nagura stone creates a slurry on the surface of the stone that cushions the blade in the final stages of sharpening. The last stroke on the stone is a pull stroke and the blade is tipped slightly upward as it comes off the stone which creates a fine micro bevel. The wire edge is then removed by laying the blade on its back on the same stone and a few light strokes are then made to remove it. There is no need for leather stropping as the process blunts the fine edge of a well made tool. It requires many years of practice to be able to hold a blade on its bevel accurately free handed and so it is better to use a sharpening jig to hold the tool to the correct bevel as there is a tendency to create a belly in a blade that is not accurately held on the stone. A belly on a blade reduces its efficiency. Hand holding a blade is kind of like how to get to Carnegie Hall, Practice, Practice, Practice.
Jay

Hugh MacD
02-10-2016, 11:40 AM
I've experimented around a lot and haven't really settled on any one system. What I do depends on the need at hand, whether it's just a quick "touch up" or a major flattening and re-bevel. DEFINITELY pickup Leonard Lee's book, keep in mind the fact that there are two components to "sharp": Bevel angle and "keenness", the flatness of the intersecting planes that define your bevel. One of my favorite tools in my sharpening kit is a small, lighted magnifier from Radio Shack. It's helped me correct a lot of newbie errors by letting me actually see what I'm doing...up close and personal...much better than the ol' "thumbnail" test. Have fun and practice, practice, practice! All of my friends have nice sharp tools and I reaped the benefit:)

Helder0906
02-10-2016, 04:50 PM
I use a cheap gauge like in the movie from lee nielsen and adjusted it correspondingly (you tube). As Stones I use both a DMT diamond stone (course) and Japanese water stones (fine and extra fine. The diamond stone I use for the first part when a or plane iron is very dull. I use it too to flatten the water stones. To set the gauge quickly and consistently I have prepared a mold as is pictured in the LN movie.

I used a electric grinder. And gave this up. The consistent bevel was my issue there.

Regards, Christiaan

Stiletto
02-10-2016, 07:28 PM
I use inexpensive Diamond plates. For the final polish, a well used fine diamond plate is very good as it doesnt have the extra cut that they usually offer.

SMARTINSEN
02-10-2016, 07:59 PM
Ron Hock's book on sharpening is very good.

http://www.hocktools.com/

i guess I am Neanderthalish, still using an oilstone. They have the advantage that they stay flatter much longer, and they need no special care in sub-freezing temps. Light oil cut back with kerosene and usually a veritas MK II jig, though I will often touch up freehand.

I will get close to the edge, being very careful not to burn it, on the grinding wheel. Then, starting with medium, and fine India stone. Finally a third finishing stone, I do not know what it is, from a junk sale long ago, about comparable to a hard black Arkansas stone.

Scary sharp method is very expensive in consumables.

Has anyone used Shapton?

http://www.bestsharpeningstones.com/catalog/Shapton-Glass-Stones.htm?gclid=CI_r25nB7soCFcoWHwodkFoE9A

Oldad
02-10-2016, 08:25 PM
If the edge needs more than honing I go to my permanently upside down mounted belt sander, well worn fine grit and touch up the edge, then go to 300 grit wet dry paper on a hard wood block, glass would probably be better, and hone the edge. Works pretty well for chisels and plane irons..

Pitsligo
02-11-2016, 12:02 AM
Another Neanderthal, here: I like oil stones. Waschita (I tried to spell it correctly, but it got bleeped!), then soft Arkansas, then black Arkansas, then a leather strop with green compound.

If I really need to work a blade, to take out a small nick, I'll use wet/dry paper on a glass plate. Start with something brutally coarse, like 300 grit, and work it up the grits until it's time to go back to the Waschita.

With both of those (except for the stropping) I use the Veritas Mk2 guide.

A big nick, or to re-true a blade, I'll use the slow-grinder with a soft (white) wheel, with one of Lee Valley's grinder rests to make sure the blade stays square to the wheel.

But as much as I practice, practice, practice, I'm still a long way from Carnegie Hall. Even with Leonard Lee's book well-thumbed and close at hand, sharpening isn't my forte. It takes me a long time to get an edge I'm happy with. And it's a poor craftsman that blames his tools...

Alex

Lew Barrett
02-11-2016, 01:48 AM
I use a graduated set of Japanese water stones because that's what I bought years ago. My polishing stone is 10000 grit and quite soft so requires care in use. I keep them in a full five gallon bucket so they're always good and add a few drops of clorox to the water to keep it from going off. I also have 2 relatively coarser Norton water stones I use for flattening the backs and starting the process on tools that have taken a hit or gone dull. I use wet/dry sandpaper too and find it is a very efficient system, but most often use my water stones. What I reach for depends more on my working situation and what is convenient, but if I'm going to really renew an edge, it's the stones. I bought a simple (and cheap) roller guide years ago at Hardwicks and use it religiously. That's the key to my system and any success I have at the task.

I enjoy sharpening, but maybe not as much as I used to.

wizbang 13
02-11-2016, 02:41 AM
Boats , we are building boats right?
We hit glue, plywood, metal fastenings, crazy grain.
Grinder and belt sander.

Rick E
02-11-2016, 11:40 AM
Thanks to all for the many responsese. Much more information than I anticipated:)

Great stuff Y>

Thanks

Rick

Jay Greer
02-11-2016, 04:18 PM
One extra comment from a guy who started out using oil stones; if I didn't care about the staining of my work and dirty hands from the oil, I would still use them. Water stones as once I got used to them, I found they were much more efficient to use and, they don't hold on to the swarf and rinse clean in fresh water.
No stropping is needed either.
Jay

Paul Pless
02-11-2016, 04:26 PM
Thanks to all for the many responsese. Much more information than I anticipated:)

Great stuff Y>

Thanks

Rickthis is a drop in the bucket, i assure you. . .

phil_mclean
02-11-2016, 07:15 PM
As a heretic, I go with the WorkSharp system (http://www.woodcraft.com/Product/149512/WS-3000-Wide-Blade-Attachment.aspx?gclid=CjwKEAiA__C1BRDqyJOQ8_Tq230S JABWBSxnp4KyYmzkrjWn_CiA_nH8T6U4CDWdw-9aJ46SmvNofBoC-FXw_wcB). I use a guide to slide the chisel/blade on and off the , sometimes quick touch from below. It is quick, easy, reliable, and permanently mounted on a secondary table right next to the shop sink. I can use it without really interrupting my work... therefore am more likely to use it often. I agree with wizbang, in that it's gotta meet the standard required. I am not building a work of art, but want to use a sharp tool. It's much, much better than I'd get with similar time expenditure and investment using any other system.

Jay Greer
02-12-2016, 11:31 AM
I always wanted to invest in one of those fancy horizontal sharpening grinders that were first invented for use in the butcher trade and produce a keen edge that is not hollow ground but rather, to a correct pre-set bevel. Most of them are rather expensive, costing several hundred dollars, and so I always shied away from them.
If the bevel set and blade grip are ridged enough to not allow a blade to have more material removed from one side of a blade than the other, I should think such a tool would be a great aid. However, with the advent of diamond plates and water stones, I found sharpening to be not all that much a problem and so have settled in with that system as it is really fast once you get the hang of it. I do avoid stropping plane and chisel blades as it slightly rolls over the back side of the tool making it less effective than if finished on an ultra fine finish water stone. I do strop my carving gouges though as the tool will then ride up on the slightly polished bevel and leave a cleaner cut when carving is done.
Jay

J.Madison
02-12-2016, 06:31 PM
I use wet/dry sandpaper on my cast iron table saw surface. It costs almost nothing. I lube with WD-40.

You can find up to 3000 grit for polishing at auto body shops.

Hugh MacD
02-12-2016, 06:59 PM
I use wet/dry sandpaper on my cast iron table saw surface. It costs almost nothing. I lube with WD-40.

You can find up to 3000 grit for polishing at auto body shops.

Cool! The finest I'd found around here was 2000 (plenty fine for my purposes...I ain't that good :) but I was going through it at an alarming rate sharpening tools for our Archery guild. I was getting it at hardware stores and it was a bit expensive so I used the expenditure as rationale to buy myself a Jet wet wheel and, of course, I still use sandpaper, waterstones, oilstones and diamond plates for various nefarious purposes, just a little less. Where'd you find it the cheapest?

Stiletto
02-12-2016, 07:31 PM
One extra comment from a guy who started out using oil stones; if I didn't care about the staining of my work and dirty hands from the oil, I would still use them.
Jay

That is a very good point.

Lugalong
02-12-2016, 09:17 PM
Since the following methods have not been suggested, I'll toss them in -- thin grinding discs (down to 1mm) on a 4 inch grinder, will take off metal without producing much heat at the contact area, and are easily portable for work almost anywhere.

Discs worn down to a smaller diameter can be used to create a nicely hollow edge if they are run carefully up and down the tool edge being sharpened........I make knives from broken bits of mechanical hacksaw blades, getting a hollow edge cut into about a 6 inch length of blade quicker than any other basic shop machine.

For chisels, sharpen the edge to a burr, then thump it onto a block of wood across the grain. This will bend and break off the burr, so that finishing with a stone or sandpaper starts with a cleaner edge.

Hugh MacD
02-12-2016, 10:47 PM
One extra comment from a guy who started out using oil stones; if I didn't care about the staining of my work and dirty hands from the oil, I would still use them. Water stones as once I got used to them, I found they were much more efficient to use and, they don't hold on to the swarf and rinse clean in fresh water.
No stropping is needed either.
Jay
I still have a set of 3 Norton oilstones that I use if I have to do a lot of reshaping on a blade. I've salvaged several great old drawknives from oblivion when people sharpened the curved blades into a straight line. Yeah...they're messy, but it clans up and nothing I've found cuts faster.

Jay Greer
02-13-2016, 01:08 PM
Hugh, I agree with you on this one. In fact I do the same thing when sharpening my tools that require a stone to be worked free hand on the blade. Here, an oil stone holds its lube better than a water stone will. I still have my Washeta and black Arkansaw Stones I use for that purpose.

Another point to note here is that so far as hollow grind is concerned, I must say that a hollow ground blade is not as effective as one that has a flat bevel all the way up the ramp of the cutting edge angle. This is why I mentioned here that the flat surface grinders that do not produce a hollow ground edge are superior to a round wheel that grinds a hollow. A case in point was shown to me at an industrial woodworking machinery show I attended several years ago; a Japanese manufacturer was demonstrating a veneer cutting machine that used a single rigid blade that was set on an angle to the direction of the cut that was made from stock held in a hydraulic ram powered carriage. That blade was nearly an inch thick and was sharpened to a single flat bevel. As the log was forced against the blade in one smooth motion, a veneer less than a mm in thickness was smoothly shaved off in one continuous sheet. It was amazing to watch. I note here that all Japanese cutting tools for wood are sharpened to a flat bevel which experiance has taught me is much more effective than a hollow bevel is. If I do have a blade that gets so badly damaged that I must resort to a grinder over a diamond plate, I find that the tool does not really work well until the hollow grind is finally honed out of the tool blade.
Jay

Hugh MacD
02-13-2016, 04:28 PM
I agree, Jay:)
fer several years of using the Jet I'm finding the hollow grind doesn't support the edge as well, but for most of the light stuff I'm using it for it works "OK". If the Jet finally kicks the bucket (it's been nauseatingly reliable) I'll switch to a flat stone, but I can't rationalize the switch for now. It's also better for drawknives, which I don't think I could sharpen on a flat wheel. Although the best drawknife tool I found is a "T" of 2x6 set into my vise with a plate of glass w/sandpaper (ScarySharp) glued to the top. Leaves plenty of room for the handles. I kinda like the hollow grind on my paring chisels, too. Makes 'em really easy to touch up. But on anything I'm using a mallet on or that gets heavy force applied (plane irons) I keep a flat bevel.

Tomcat
02-13-2016, 05:48 PM
The best system is a belt sander combined with diamond paste on leather or Iron. Boatbuilding tools are varied and rarely to some exquisite finish, hair popping should be fine. For axes, drawknives, slicks, and so forth, you might find yourself wanting a convex edge. For chisels, and handplanes a concave edge; For scrapers ad 90 degree edge, etc... The belt grinder will make all that possible to any finish you want, the diamonds restore an edge faster than anything I have tried, just buy some 14K off ebay.

With a belt sander you can use a platen or wheel to engineer whatever diameter of concavity you want, which pretty much eliminates problems of edge weakening while retaining whatever advantages of concavity you desire.

Tomcat
02-13-2016, 05:55 PM
Hugh, I agree with you on this one. In fact I do the same thing when sharpening my tools that require a stone to be worked free hand on the blade. Here, an oil stone holds its lube better than a water stone will. I still have my Washeta and black Arkansaw Stones I use for that purpose.

Another point to note here is that so far as hollow grind is concerned, I must say that a hollow ground blade is not as effective as one that has a flat bevel all the way up the ramp of the cutting edge angle. This is why I mentioned here that the flat surface grinders that do not produce a hollow ground edge are superior to a round wheel that grinds a hollow. A case in point was shown to me at an industrial woodworking machinery show I attended several years ago; a Japanese manufacturer was demonstrating a veneer cutting machine that used a single rigid blade that was set on an angle to the direction of the cut that was made from stock held in a hydraulic ram powered carriage. That blade was nearly an inch thick and was sharpened to a single flat bevel. As the log was forced against the blade in one smooth motion, a veneer less than a mm in thickness was smoothly shaved off in one continuous sheet. It was amazing to watch. I note here that all Japanese cutting tools for wood are sharpened to a flat bevel which experiance has taught me is much more effective than a hollow bevel is. If I do have a blade that gets so badly damaged that I must resort to a grinder over a diamond plate, I find that the tool does not really work well until the hollow grind is finally honed out of the tool blade.
Jay

I learned from the Japanese system starting in the 70s, and flat is still my preferred default, but there is rarely much real difference. What is different is if you hollow grind the edge at the same angle as you otherwise would have flat ground it. Then the actual edge angle is much lower than on a straight bevel, which may be good or bad depending on the geometry you were after, but it is certainly different. There is also a kick, almost like a chip breaker. The diameter of your contact wheel is critical. The larger the diameter, the more like a flat bevel it will be, but it will always have two points of contact only when you move onto the honing stone (if you do) and that makes honing faster.

Dave Hadfield
02-13-2016, 06:28 PM
Lee Valley rules.

I tried all sorts of things. Then I tried something which was so simple and quick and deadly sharp I've never been tempted to do anything else.

I first use a LV wheeled jig on a waterstone to establish the correct bevel on the blade.

Then I put it to a hard felt wheel on a bench grinder dressed with the LV green honing compound. That produces a mirror-finish that is scary sharp -- and it does it in seconds. Further touch up can be done by a simple swipe across the wheel.

It's amazing, that particular compound on the wheel. For one job I was turning sheaves of jotoba on a lathe. That wood is hard as aluminum. Only the sharpest lathe tool cut it. But a quick pass across the felt wheel every couple of minutes was perfect.

No gimmick. It works.

Dave

Jay Greer
02-13-2016, 08:16 PM
Sharpening has a weird learning curve which, is really evident from the varied opinions voiced here. I was a well seasoned boat builder when I had my first encounter with Japanese tools and water stones. One of my employees was a fully qualified temple builder who was on a visit to California and ended up working on a fifty foot catamaran we were building for Jim Dutcher the wildlife photographer. Tad was fast and extremely accurate in his work and was a very quiet kind of guy. Out of curiosity I asked him to teach me a bit about his tools and way of working. He was gracious enough to allow me to try one of his planes and a chisel. The chisel was sharper than any Western too I had ever used. I was amazed after I tried some of his gear. I then invested in a few tools which included a block plane and a long smoother plus a saw and a couple of chisels and water stones. It didn't take long till I was hooked on Japanese tools and especially their water stones. I won't go into much more here other than to explain that the non hollow ground blade produces less resistance, has less tendency to tear out the grain and also adds to the polish of the cut often, making sanding hardly necessary. I am not bragging but I once entered of planing contest and placed third with a flat chip that was sixteen feet long and so thin as to be nearly transparent. The wood was VG Port Ordford Cedar.
Most Japanese workers don't use a jig to hold the blades when sharpening them. This is due to the fact that the bevel portion of most of the blades is thick enough to obviate the need of a jig. And, the back side of their blades are set up with a gentle hollow grind that allows the worker to place the down force of his fingers directly over the blade edge without having them slip off and leave bloody finger prints on the stone. It takes a while to get used to the process but once learned it is much faster than the regular "Gaijin" round eye way! I hardly ever use Western hand tools any more.
Jay

Canoeyawl
02-13-2016, 11:38 PM
In the woodworking learning curve, I remember exactly when I learned how to sharpen my tools. (My experience was much like Jay's, where an unassuming man that I worked with suggested, "here try my chisel"... Everything changed right then, like switching on a light)

One advantage of Japanese edged tools is they are a laminate of a soft iron core with a very hard steel envelope. Generally the hard steel is shaped like a "U" with softer wrought iron in the center or "top" This malleable core or layer allows for a harder edge than most western tools while the soft core sharpens away in much less time. A western chisel or plane iron would be too brittle and fragile if it was through hardened to the same degree as the Japanese version. Another advantage is the softer back of a plane iron can be beaten (tapped) with a little hammer just away from the edge and the back will actually bend a bit making it a simple matter to "flatten" (we are talking slightly here, very slightly). I have some laminated Japanese plane irons that fit my Stanley/Bailey planes - lovely things.
(I use a homemade wooden treadle to power an ancient 24" grindstone that I found abandoned in a field, for gross stock removal to repair a damaged edge. It does leave a slight hollow grind but that goes away very quickly leaving a "flat" edge. I finish with waterstones to about 5000)

Gerarddm
02-13-2016, 11:53 PM
With the Veritas jig I get consistent results. But the only thing that continues to elude me is properly sharpening a cabinet scraper. Just can't get that consistent fine curled edge. Aargh!

Rob540
02-14-2016, 01:15 AM
With the Veritas jig I get consistent results. But the only thing that continues to elude me is properly sharpening a cabinet scraper. Just can't get that consistent fine curled edge. Aargh!
There is a tool for that with a wooden handle and a steel round bar set across a rebate in the end....I've had one for years but don't remember where I found it. Here, scrapers are traditionally made by squaring the edge and rounding over on both sides, but in my violin making training I was taught to make (especially curvy shaped) scrapers with a single edge, just like a really thin, flat, wide chisel, (thin flexible Swedish steel generally) and just round over one way. So for a square scraper I'd bevel opposing edges (2 out of 4 sides maybe) and have one set aggressively and one set fine. With shaped scrapers on compound surfaces I'd bevel all round the piece and be able to use different sized curves in different places to get into hollows. Now that isn't generally necessary on a boat, but you get my drift I hope.

Canoeyawl
02-14-2016, 02:11 PM
For burnishing scraper blades I use a 5/8" high speed or carbide drill blank.
The surface finish and hardness of the burnisher are important as they will transmit any surface irregularities to the scraper.
Readily available on ebay

Christine DeMerchant
02-16-2016, 05:44 PM
It depends on what I'm doing. For my plane if I'm cutting into something that might have epoxy and knots I just use the grinder with a fairly fine grit, and clean up the burr with 1200 sandpaper. Fast and ok for roughing in. Thickened epoxy is hard on the iron and can damage the edge so the grinder works.
If I'm doing fine work I use wet/dry sandpaper on plate glass. That's also how I do the chisels and the block planes.