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Thomas Colson
02-11-2021, 8:34 AM
As I type this, I can barely press the keys on the keyboard. After carpal tunnel surgery, which was rated as "20" on a pain scale of 1-10 (pre-surgery), the carpal tunnel issue is gone, at the expense of loss of wrist strength (I had a choice, suffer all day long, or suffer when I hold a power tool for 1 minute). I digress....so back to sharpening, this really affects taking a planer blade back to a primary bevel on a water stone. I can maybe get 30 strokes before I have to stop for a few minutes. 3 hours last night on a #5 blade on 150 grit, and I'm still no where near ready to move up to higher grits. I am using a honing guide to hold at proper angle and 6" water stones. I have a PC 6" bench grinder, but the wheels are pretty coarse and I feel like I'd turn my blades into lawnmower blades pretty quickly. Are there wheels I can put on that where I could "maybe" get a good hollow grind without melting the blade? Thanks in advance for any well-intentioned advice about changing how I hold my hands on the stones, but I'm done with hand-grinding, not open to trying other ways. I need to make this work with the assist of a powered grinder then I can take my final honing by hand on the higher grit stones. The wrist pain lasts for days after doing something like this. Or am I going to need to get something like a https://www.amazon.com/Work-Sharp-WS3000-Wood-Sharpener?

Patrick Whitehorn
02-11-2021, 9:38 AM
I use a setup modified from Derek Cohen's setup here: http://inthewoodshop.com/WoodworkTechniques/UltimateGrindingSharpeningSetUp.html with the difference that I use a full-speed 6" grinder with a CBN wheel from LV. It is a little fussy to set up - each chisel and plane blade has to be checked for angle every time you change - but it is super fast.

I hope your wrists heal quickly - my mother had that when I was a child and I can still remember helping her with everyday activities while she was recovering.

Patrick

Tim Best
02-11-2021, 12:55 PM
Hi Thomas,

Glad the operation went well. The thought of resetting a primary bevel on a water stone is an unpleasant one without any added factors.

Honestly, I use the 46 grit blue/grey wheel that came with the grinder. The 46 grit is so aggressive that metal does not have to touch the wheel for very long, reducing the chances of overheating. When I started grinding irons and chisels, I had no experience but I have yet to burn/blue a chisel or plane iron. A good tool rest, light touch, and a slow/variable speed grinder are essential. I have an older Delta variable speed and I leave it at +/- 2000 rpm. It was probably set a little slower in the very beginning. David Weaver has recently done some testing on various wheels. His thoughts/results are posted on Woodcentral. Not to put words in his mouth, but the gist is that the stock wheels are normally pretty good for establishing hollow grind primary bevels. CBN wheels seem to be more fool proof, but also more costly. I grind with my fingers pretty close to the edge of the blade so I can feel the heat build up. I do not even keep a cup of water near the grinder any more.

Tim

Robert Engel
02-11-2021, 1:17 PM
Use the Norton white wheels and grind a hollow bevel the. Yourself to go right to stones a d secondary bevel.

Don’t use a fine grit produces too much heat

Scott Winners
02-11-2021, 1:30 PM
I guess I will go ahead and play. I use the 120 grit wheel that came with my variable speed 6" grinder. The finer point is to make a wooden block to set up the (factory) rest on the grinder. Just a piece of good straight stock, 3/4 inch thick is plenty, plane one edge flat, mark the angle you want carefully and then rermove that little triangle and dress to the line. Now use the wooden guide on the tool rest to get the angle of the tool rest correct, which is fiddly.

Once the angle is correct I freehand the blade back and forth across the wheel on the tool rest. Keep a square handy to make sure you are keeping the grind perpendicular to the long axis of the blade, and I do use water quenching every pass. Accorss the wheel, quench (slow count to five) check for square, across the whee the other way, quench, slow count to five, check for square, continue.

I do get blue bits with some regularity and have to grind off some more, but _usually_ they are superficial blue bits that didnt burn all the way through. As i get closer and closer to the final angle the wheel face gets closere and closer to the edge of the blade and the extra metal available to carry away heat gets less and less so the risk of a carbon burn gooes up and up. may want to start with a cheap tool, remember the closer you are to finished the higher your risk of losing temper/ burning out carbon.

if I come into big dollars someday I would go to an 8 inch grinder and a CBN, but I have more pressing challenges to handle with the money I do have.

Andrew Seemann
02-11-2021, 1:36 PM
I've got a Tormek that I picked up for a steal on clearance years ago. It is definitely faster and less work than hand sharpening, although it does take some pressure from your hands and fingers to use. Most systems where you need to hold a blade against a wheel will be like that though.

I can't imagine doing a primary bevel by hand anymore; that is just painful to think about. I think that would give me carpal tunnel alone.


As an aside, Hand Tool woodworkers often get caught up in Romantic ideas of what "Hand Tool Woodworking" should be. These ideas don't always match our actual circumstances, time availability, and (let's be honest) current physical capabilities. Don't let other people's ideals make your woodworking miserable. There is no shame or disgrace in using electricity for what it was meant for: taking the drudgery out of life. I can't hand plane for as long as I could in my 30s, so I have embraced abrasives again. My body is much happier for it, and I can actually get things done on my wife's schedule.

Don Dorn
02-11-2021, 2:32 PM
I have a short read book called sharpening with water stones by Ian Kirby. While I use diamond stones, there is a section on how to use inexpensive items to make a standard grinder a great tool for bevel grinding with very cheap items (less than $5). I've been using it for about 10 years now and have no interest in changing because it works so well - and fast. Then, it's hand honing on via Paul Sellers. Sometimes we go full circle with things to find the easiest method normally works the best.

Gary Focht
02-11-2021, 3:02 PM
How long ago was the surgery? My carpal tunnel was gone immediately following surgery, but it did take a few months to return to normal. A year or two later I got De Quervain Syndrome in the same wrist. That was much more painful for me. I was close to surgery for that, but the second shot in the wrist cleared it up and no issues since.

I use a CBN wheel on a half-speed grinder. Works well for me, but I still need to be a bit careful. I prefer it over the blue wheel I had previously tried.

Thomas Wilson
02-11-2021, 3:28 PM
I use an old fashioned solution. I have a Makita Wet Grinder 98202 also known as the mud slinger. I have a special holder from Highland Woodworking for chisels and plane blades. The grinder is designed for and I bought it for jointer and planer blades. I have replaced my straight knives with segmented helical heads so the grinder is not needed for that anymore. I keep the Makita for regrinding bevels. The tool rest is really steady and all you have to do to get a square bevel is square the blade to the special holder. I works great. You just have to wear a rubber apron.

https://www.amazon.com/Makita-98202-Horizontal-Wheel-Sharpener/dp/B0000223JC/ref=asc_df_B0000223JC/?tag=hyprod-20&linkCode=df0&hvadid=309763890402&hvpos=&hvnetw=g&hvrand=8189551594238072870&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010926&hvtargid=pla-569811470328&psc=1

ken hatch
02-11-2021, 4:07 PM
I've got a Tormek that I picked up for a steal on clearance years ago. It is definitely faster and less work than hand sharpening, although it does take some pressure from your hands and fingers to use. Most systems where you need to hold a blade against a wheel will be like that though.

I can't imagine doing a primary bevel by hand anymore; that is just painful to think about. I think that would give me carpal tunnel alone.


As an aside, Hand Tool woodworkers often get caught up in Romantic ideas of what "Hand Tool Woodworking" should be. These ideas don't always match our actual circumstances, time availability, and (let's be honest) current physical capabilities. Don't let other people's ideals make your woodworking miserable. There is no shame or disgrace in using electricity for what it was meant for: taking the drudgery out of life. I can't hand plane for as long as I could in my 30s, so I have embraced abrasives again. My body is much happier for it, and I can actually get things done on my wife's schedule.


+1 on the Tormek. I have both a Tormek and a low speed 8" grinder with a CBN wheel and the Tormek tool rest. While the Tormek is slower, time to finish is faster because with water cooling there is no need to stop to cool the cutter. BTW, I like the original Tormek stone wheel better than either a CBN or diamond wheel. Kinda the same story, the diamond/CBN may be faster grinding but the time is made up with time saved on the honing/polishing stones.

ken

ken

Jim Koepke
02-11-2021, 5:05 PM
This has worked well for me for many years > https://www.leevalley.com/en-us/shop/tools/sharpening/power-systems/48435-veritas-mk-ii-power-sharpening-system?item=05M3101

For a few years multiple blades were worked at a time. This required extra holders.

The finest abrasive is 9µ. For many jobs this may be sharp enough. For others a bit more honing on a finish stone might be prefered.

jtk

Phil Gaudio
02-11-2021, 5:08 PM
I think a Tormek might go a long way to solving your problem. It seemed like an expensive gimmick before I used one. Having lived with it for a number of years, I would never be without it.

Thomas Colson
02-11-2021, 5:22 PM
How long ago was the surgery? My carpal tunnel was gone immediately following surgery, but it did take a few months to return to normal. A year or two later I got De Quervain Syndrome in the same wrist. That was much more painful for me. I was close to surgery for that, but the second shot in the wrist cleared it up and no issues since.

I use a CBN wheel on a half-speed grinder. Works well for me, but I still need to be a bit careful. I prefer it over the blue wheel I had previously tried.

4-5 years ago. I can now hold onto the steering wheel (had the worst CT the doc said he's ever seen), but lost most of my wrist strength in my dominant hand, about 25% in other. I've adapted my other woodworking techniques, blade sharpening is next. To be honest, I really want to be a neanderthal, but every time I put an iron to stone and suffer the next day, the pair of old Sargeants I got for a steal go back in the cabinet for another 6 months and my neighbors get to hear my jet 15" all day. The practical reason I want to be a neanderthal is I have a pile of reclaimed barn oak that I want to turn into cabinets, and after having worked with it enough already, it's going to be quicker, easier, and waste less wood for me to joint it by hand.

So with the grinder, how are you a)holding it square to the wheel and b)at the desired angle?

Thomas Colson
02-11-2021, 5:31 PM
I use an old fashioned solution. I have a Makita Wet Grinder 98202 also known as the mud slinger. I have a special holder from Highland Woodworking for chisels and plane blades. The grinder is designed for and I bought it for jointer and planer blades. I have replaced my straight knives with segmented helical heads so the grinder is not needed for that anymore. I keep the Makita for regrinding bevels. The tool rest is really steady and all you have to do to get a square bevel is square the blade to the special holder. I works great. You just have to wear a rubber apron.

https://www.amazon.com/Makita-98202-Horizontal-Wheel-Sharpener/dp/B0000223JC/ref=asc_df_B0000223JC/?tag=hyprod-20&linkCode=df0&hvadid=309763890402&hvpos=&hvnetw=g&hvrand=8189551594238072870&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010926&hvtargid=pla-569811470328&psc=1


IS this the special holder?
https://www.highlandwoodworking.com/dual-usehandtooljig.aspx

Thomas Wilson
02-11-2021, 5:58 PM
IS this the special holder?
https://www.highlandwoodworking.com/dual-usehandtooljig.aspx
Yes, it is.

Gary Focht
02-11-2021, 6:06 PM
I have the Lee Valley rest for my grinder and the jig it uses, but I really don’t like the jig much and am free-handing it with regular checks with a square. I’m still fairly new to this all, but it isn’t that hard to free-hand the grind. I’m not that picky about the angle - as long as it is close to 25 degrees, I figure that is good enough.

Gary Focht
02-11-2021, 6:11 PM
Unfortunate you can’t get all your strength back. I read if carpal tunnel goes on too long, the damage could be permanent, so I got surgery in a relatively timely manner.

I swear I gave myself the carpal tunnel in one day installing crown molding. My fingertips were numb at the end of the day and it never really came back. No issues before that.

Curt Putnam
02-11-2021, 8:47 PM
Based on David Weaver's Unicorn method and the recommendation of Derek Cohen, I am slowly migrating from a Worksharp 3000 to a Rikon 8" 1725 rpm grinder with a CBN wheel and a Tormek rest. I say slowly because learning how to grind efficiently takes some effort. I bought a couple of Tormek jigs and that takes care of the square part of grinding. I also bought 2 angle setting jigs - but I do not yet fully trust that I am using them correctly, and therefore, the results are suspect.

As far as your coarse grinder wheels go, the general advice I've read is to use the coarsest wheels you can get. The most useful advice I've gotten is that all one is trying to do with a grinder is to get metal out of the way so you can hone at the angle you want.

William Fretwell
02-11-2021, 10:25 PM
I have a generic ‘Tormek’, far less money. A lot of plane blades nowadays are much thicker, this has some benefits with stiffness but sharpening at the primary 25 degree bevel is a lot of metal area. On water stones this is huge work.
I simply grind with the ‘Tormek’ to produce a concave grind between the blade edge and the inside edge. This retains the two reference edges to rest on but at least halves the metal contact on the water stones. The full support is still there as the concave is slight.
Two important points, the quality of the ‘Tormek’ grind matters not a damn as it does nothing, just gets steel out of the way! You have at least halved the work to restore the primary bevel, yes at least half the time!
The other huge benefit is it keeps you away from secondary bevels, I feel the appeal of a secondary bevel is just to get back to wood work however as the secondary bevel grows you have to re-grind the primary bevel so no time is really saved.
The only secondary bevel on my blades is from the leather strop.

Yes it’s an added expense but a huge time saver and the cheapest water wheel will do the job. Use the grinding support, keep it even and that ‘middle concave area’ will last quite some time.

Andrew Seemann
02-12-2021, 2:00 AM
I have a generic ‘Tormek’, far less money. A lot of plane blades nowadays are much thicker, this has some benefits with stiffness but sharpening at the primary 25 degree bevel is a lot of metal area. On water stones this is huge work.
I simply grind with the ‘Tormek’ to produce a concave grind between the blade edge and the inside edge. This retains the two reference edges to rest on but at least halves the metal contact on the water stones. The full support is still there as the concave is slight.
Two important points, the quality of the ‘Tormek’ grind matters not a damn as it does nothing, just gets steel out of the way! You have at least halved the work to restore the primary bevel, yes at least half the time!
The other huge benefit is it keeps you away from secondary bevels, I feel the appeal of a secondary bevel is just to get back to wood work however as the secondary bevel grows you have to re-grind the primary bevel so no time is really saved.
The only secondary bevel on my blades is from the leather strop.

Yes it’s an added expense but a huge time saver and the cheapest water wheel will do the job. Use the grinding support, keep it even and that ‘middle concave area’ will last quite some time.

Actually in this system (which is basically what I use) the hollow grind from the grinding wheel is the primary bevel, and the water stone puts on a secondary bevel. It is very slight, but it is just a little bit steeper than the primary bevel of the hollow grind, which makes it a secondary bevel.

Secondary bevels are great for most things. They do reduce the amount of metal you need to remove which makes for many quick touch ups before you need to regrind the primary bevel. Because they are steeper, they make the actual cutting edge a little stronger, yet because they are so small, they don't appreciably make the tool harder to drive like a steeper primary bevel would. Kind of the best of both worlds, stronger edge yet easy to drive, all while being quicker to sharpen.

William Fretwell
02-12-2021, 7:37 AM
So Andrew you take the concave grind all the way to the edge then the very small real edge you add at the normal flat angle you call secondary. The only problem is restoring the primary bevel consistently on a grind wheel is very difficult. That is why, on the thick blades I keep some primary bevel either side of the grind, I only think of it as removing work.
Yes small secondary bevels get you back to work faster but the typical 1 or 2 degrees dialled in on the honing jig will make little to no difference in edge strength.
I have used small secondary bevels in the past but they just grow bigger as the job progresses, now you have a primary bevel 2 degrees less than before and have to grind back. With my method now I can keep the primary bevel easily all the time, no need to remember which blade needs more work down the road.
The little knob on my Lee Valley honing guide stays put!
The wear bevel on the back of the blade needs monitoring as you try and keep it flat, that can encourage grinding back the primary bevel even sooner!

Jim Matthews
02-12-2021, 8:26 AM
I have an appreciation for hand pain and how it can afflict your daily life in unexpected ways. First and foremost - do the physical therapy.


*****


For me the difficulty is securely holding things for extended periods. I built the "swing arm" grinding set up as designed by JSK Koubou.


Really rough blades or regrinding bevels are done on a handcranked grinder with a Norton White wheel.
https://i.imgur.com/n41K7aP.jpg

Jim Koepke
02-12-2021, 10:55 AM
That looks like it would put a camber on every blade whether you want to or not.

jtk

Jim Matthews
02-12-2021, 1:29 PM
That looks like it would put a camber on every blade whether you want to or not.

jtk

It puts an even flat on blades from 1/4" to 2 1/2". The fixed point of rotation and positive registration between the blade and the "swing arm" means the blade stays flat through the arc it travels.

If the plate (or stone) is flat, the steel always maintains the same angle.

You *could* get a camber by twisting the swing arm, but I can do that free hand.https://i.imgur.com/w5w77bJ.jpg

Don Parker
02-12-2021, 3:22 PM
Robert Sorby ProEdge. Expensive, but to me, worth every penny.

Kevin Adams
02-12-2021, 5:15 PM
Robert Sorby ProEdge. Expensive, but to me, worth every penny.

I also like the Proedge. You can use jigs or freehand, just rough grind or go up to 3000 grit. I typically like a flat bevel and this makes it easy to repeat and then move to a guide on stones or even freehand on stones.

Thanks.
Kevin

Dan Grano
02-15-2021, 9:14 AM
First, I'm sorry to hear about the ongoing limits with your hand, Thomas. This thread is interesting timing for me personally. I am having carpal tunnel and cubital tunnel surgeries today (both on the right side, though I am also having trouble on my left side). And, I spent some time on the grinder yesterday repairing a damaged plane blade.

I have a Rikon 80-805 grinder and I've been pretty happy with it. It goes on sale somewhat frequently, and isn't too costly. I also got a Wolverine tool rest (just the plain rest, without the attachments for turning tools). That combination has worked pretty well for me. The wolverine rest is big enough that it helps with stability and serves as a good heat sink.

The Rikon comes with a 60 grit white friable wheel on one side and that's the one I've been using. It's the main thing I am going to look at changing, either for a CBN wheel or maybe a Norton 46 grit (blue super-cool wheel), something that will speed the process. With numbness and pain plus loss of dexterity I think that speed is at a premium, as things start to fall apart (both accuracy and patience) the longer I am working at the wheel.

James Pallas
02-15-2021, 10:04 AM
I have always used a standard 6” grinder with a 46 grit wheel. Unless you have unusual damage little metal is being removed. A light touch, the baby bird thing, is plenty. Water to dip in, just in case. I did purchase a CBN wheel last year. It’s nice because less work on the stones. I use it more for metal cutting tools than woodwork tools. I guess practice is good. I have to intentionally do it in order to blue a tool nowadays. Keep the wheel dressed, coarse wheels better than fine for heat. Accuracy to me is not a problem. I can tell the difference between 20 and 25 degrees in use but not 20 and 22 degrees for instance.

Bill White
02-17-2021, 2:21 PM
Thomas, glad to hear about your use of the Makita. I have it, and use it often. I kinda think that it is the unsung hero of the sharpening world.

Thomas Wilson
02-17-2021, 2:50 PM
Thomas, glad to hear about your use of the Makita. I have it, and use it often. I kinda think that it is the unsung hero of the sharpening world.

Yes. it is, Bill. I have used it for years. I bought mine before the Tormek came out and never felt the need to upgrade. I am on my second green wheel. I sharpen everything on it. I use the tool rest and holders for plane blades and chisels. I sharpen kitchen knives and lathe lathe tools freehand. I think my only objection is the mud that comes off sometimes.

Thomas Colson
03-08-2021, 10:06 AM
So the makita is now on sale half price, and I ordered one. However, I'm curious as to how https://www.highlandwoodworking.com/dual-usehandtooljig.aspx is set up on this machine? Anyone know of any videos, or pictures, of using https://www.highlandwoodworking.com/dual-usehandtooljig.aspx to sharpen plane irons on the makita?