What do you use to "grind" primary bevel on plane blades?

[Mike Allen1010]

Like many of the Nenders here on the creek, I consider sharpening edge tools to be an important shop skill. I'd like to think I'm not obsessive about it, but I have an approach that works for me and keeps most fairly planes and chisels fairly sharp most of the time.

I rely primarily on Waterstone's and typically use a 25 degree primary bevel and a 30 secondary bevel. I'm comfortable achieving a sharp edge by working the blade back and secondary bevel.

I recently started a bench build that involved laminating 8/4 maple into an 22" x 8' x 3" thick bench top. Three solid days of planeing for the glue up and flattening of the bench top have me questioning my sharpening process.

After multiple sharpenings, I typically restore the primary bevel w/ a horizontal electric waterstone "grinder" I've had for 25 years. Problem is it's messy and slow. I've also used a MK II honing guide And a 200 grit "Dragon" waterstone. It cuts much faster but "dishes" quickly.

My question is do I need to Aquire and learn to use an electric bench grinder? Are the results, including learning curve and risk of burned edges worth it? Could I go with an aggressive (120 -220 grit) diamond stone?

Any recommendations About both techniques and tools would be very much appreciated!

Thanks, Mike

[Chris Griggs]

My question is do I need to Aquire and learn to use an electric bench grinder? Are the results, including learning curve and risk of burned edges worth it? Could I go with an aggressive (120 -220 grit) diamond stone?

Any recommendations About both techniques and tools would be very much appreciated!

Thanks, Mike

Do you need one? no. Is it worth having and learning to use one. YES!!!!! I can't believe I went so long w/o a grinder. You don't need a fancy one. Just a standard 6" grinder. If the tools rests are fully adjustable, then you don't even need to make or buy a new rest and you most certainly don't need to immediately replace the gray wheels. Yes better rests and friable wheels are nice, but not a requirement of good grinding. Honestly, in my experience edges don't burn all that suddenly unless you are using a lot of pressure, not dressing you wheels, or just not paying attention to the temperature of the steel. Keep your hand near the cutting edge and you almost always will feel the heat well before it burns. Pay attention and error on the side of using too light of pressure. As you've likely read many times before, the hollow grind is also nice to have as it mean there is less metal to hone on your stones (like a mirco bevel) and if you so desire it also make freehand honing easier. And yes, I find a grinder to be preferable (read: much quicker) to a course stone (diamond or water) when it comes to reestablishing bevels.

[Jerome Hanby]

I thik Woodcraft has had their slow speed 8" grinder on sale. Slow speed will help keep the heat down and 8" reduces the hollow in the grind a bit.

[Jim Koepke]

There are many ways to accomplish this task. None of them are more right than any other.

I use two methods and will eventually have a third. The third will be a foot powered grinding wheel.

The electric system now used in my shop is a Veritas Mk II Power Sharpening System. It is a very good set up for a wide variety of blades.

My human powered set up is a 4 foot chunk of granite on a stand with adhesive backed 80 grit abrasive strip. I have gotten blades hot on this, but not hot enough to hurt the metal or burn my fingers.

My main reason for wanting a grinder is I have blades that are difficult to work on my other two set ups. They are scythe blades and other non-woodworking tools.

jtk

[Jim Koepke]

I forgot to mention, the hollow grind, mentioned by others, has an advantage when hand sharpening.

It actually helps one to feel the blade on the stone. It just "clicks" when the blade is on the stone properly.

You will notice it the first time you go to free hand a hollow ground blade.

jtk

[Jessica Pierce-LaRose]

I agree with Chris, and Jim.

There's a lot of different ways to do this, and really, whatever makes you and your tools happy is good enough. I recently got a 6" variable speed grinder for christmas, and having one in my shop is a godsend - I'd struggled with my fathers terrible grinder when I needed to remove a nick, but this one is so much nicer it makes the progress easier. Now that I have one and don't need to make a special trip to use one, I use it and it makes things nicer for me. Like Jim said, it makes free hand grinding a lot easier, having two bearing points, finding the bevel is a lot easier. I can free hand grind a flat bevel, but a lot of times if the bevel is narrow (like a plane iron) I end up slowly increasing the angle inadvertently - particularly if I try to microbevel (so I don't need to hone the whole bevel) - the hollow grind just make things easier. Not having to pull out a jig, and removing less metal when I free hand grind makes the whole process faster, so I do it more often.

The only time I have issues with burning the edges of my blades is if I try to go all the way to a burr on the grinder on narrow/thin blades - with less metal to absorb the heat on something like a thing 1/4" chisel makes them more susceptible to overheating - so having the variable speed is nice here. But these blades also have less metal to remove, so grinding back by hand with a coarse stone or paper or whatever is not that hard. On a plane iron (I've been using LV replacement blades for my Stanley planes - so a bit thicker, but not that thick) I can keep running at full speed right to the edge - as it gets close, I quench a little more frequently, but it's not too bad. Make sure my wheel is slightly crowned helps keep from burning the corners. On something thick like my Lie Nielsen LA jack plane iron, I think I'd have to try to burn it before I could accidently.

These past few days I just did a lot of sharpening, and finally got freehand technique down to where I feel like I've really got it down perfect compared to where I had been. It's been kind of eye opening. Getting better at setting my planes up makes the process quicker too. I haven't even been using my 1000 grit stone lately; as I've been honing more often, and the whole process is more enjoyable.

[Zahid Naqvi]

I am probably a small minority here, but I acquired the HF slow wet grinder (http://images.harborfreight.com/manuals/95000-95999/95236.pdf) at one of their sales. I don't think they carry this model anymore. It took a while to get everything aligned and straightened, but once it's done the grinder is a huge time saver. I think like others have mentioned having a "system" in place is very important. For example I establish the primary bevel on the HF grinder, follow that up with honing on Shapton glass stones and strop at the end. I tend of have dedicated sharpening sessions where I sharpen everything, I lay out everything and then go from one stations to the other sharpening blades/chisels step by step. While in the middle of a big job I only have to hone and or touch up the secondary bevel every now and then, no need to go back to the grinder. As I said having a slow or wet grinder saves a lot of time, but on the other hand if you frequently touch up your cutting edges you don't go to the grinder that often. For me going back to the grinder means I dropped the tool and damaged the edge or have done so much honing that the hollow grind is almost worn flat.

[Jason Coen]

The $67 6" Porter-Cable grinder that Lowes has right now is tough to beat. With a Norton 46-grit 3X wheel you honestly have make a concerted effort to burn the edge. If you're sensible about it and quench the tool whenever it starts to feel hot then burning just isn't an issue.

I grind all my plane blades with this setup at 25 degrees. I then hone/polish at 30 degrees with an Eclipse (or whatever the knock-off is) honing guide. Once the microbevel gets too large for speedy honing, it goes back to the grinder at 25 degrees to shrink it just shy of the edge. Rinse, repeat.

For chisels, I grind on the Tormek at 33 degrees (or so) for anything that will be beat with a mallet, and 25 degrees (or so) for paring chisels. I then hone/polish freehand using the hollow grind to register the chisel on the stone. A neat trick I've found with the Tormek (and I'm sure I'm not the first to discover this) is to use the turning tool setting jig to establish the angles for anything that I freehand sharpen. I have an extra universal support that I keep installed in the horizontal base and grind from this position instead of the vertical position. In the vertical position I leave the truing/dressing tool installed. To grind a chisel, I set its extension from the square edge jig using the guides on the back of the turning tool setting jig and then also set the extension for the universal support from the the turning tool setting jig. Doing this versus grinding from the vertical position eliminates a lot of fiddling and fussing to get the angle just right and is much quicker.

[David Weaver]

That lowes grinder looked pretty good. If I recall, it was less than the cost of a diamond hone in most cases.

I use a 6" grinder with a two-piece rest. I've used two different grinders, a cheap one and an expensive one. They both do a fine job, I only got the expensive one because I wanted to support a US industry instead of tweaking or diagnosing a balance issue with the cheap one (which may have just been the wheels anyway).

[James Owen]

I use an extra-coarse or an extra-extra-coarse diamond stone for quick removal of lots of metal, such as removing chips or initial flattening of the backs and bevels of vintage chisels, etc. It's reasonably fast and leaves a "utility" edge on your tool that's quick and easy to sharpen/hone up to a furniture-making quality edge.

FWIW, I use an 8" electric grinder only for my HSS turning tools; everything else gets sharpened by hand.

[Jim Matthews]

I've taken three classes that involved extensive grinding to establish primary bevels and put a camber on some plane blades.

I think sandpaper stuck to a granite slab is nearly as fast, offers considerably better control (which may just be tactile feedback), less mess and lower cost.
I don't have a dedicated place to put a grinder, so the utility of something that needs it's own space is questionable in my shop.

I do have a 1" belt sander from Lee Valley that I use when the blade in question is chipped. For getting rid of metal, nothing beats a motor.
To get things sharp, I feel the less I need to do (or re-do), the better.

[Zach England]

Hand-held belt sander turned to its lowest speed and clamped upside down into my face vise. Crude, I know, but it works for me. I only use that if I have to remove a lot of metal. Otherwise I use a big green water stone--I think it was labeled at 200 grit.

[Carl Beckett]

If I really wreck something I resurface it on a friable wheel I put on my table saw arbor.

But for smaller jobs (plane irons), I use a scary sharp method (sandpaper) stuck on a wheel of a Lap-Sharp 200. I like that I can set it up and just let it go (sit something on the foot switch and walk away..... )

Then the Lap-Sharp does all my finishing and honing (occasionally I will hone a small chisel on an Arkansas oil stone, but the lap sharp has become my go to)

Perhaps unconventional method combinations. But as most anyone here has stated at one time or another re:sharpening - whatever works for you.

[Christopher Charles]

I've got one of the woodcraft slow speed grinders and can definitely recommend it. Figured out how to freehand grind with a crowned wheel (some practice on an old blade goes a long way). That said, a sheet of floor sander sand paper on a table saw would probably do too (i've used 12"x18" sheets), but I don't regret the purchase.

Good luck.

C

[Mike Brady]

Norton India coarse. Nothing I have found cuts as fast for primary bevels. I use Arky's for O-1 steel and water stones for A2 after that. All with and Eclipse jig.

[Zach Dillinger]

High speed Baldor electric grinder I inherited from my dad. I used to use a hand-cranked grinder, but I prefer being able to grind with both hands. I use a very coarse wheel that cuts very quickly and I almost never blue the tool.

[Zach England]

I want one of these:
http://treadleit.info/sites/default/files/mainsite/images/02holtztreadlegrinder-w.jpg

[James Owen]

That's NICE!!!

[Gary Curtis]

A Veritas MK II powered sharpener. It is messy, but fast. I'm trolling around for a big motor to power a 10" wheel so I can create some hollow grinds.

[Charlie MacGregor]

So is the hollow created by a 6" wheel easier to register on a waterstone than say an 8" or 10" wheel, or is the geometry insignificant in this regard?
Thanks

[John Dykes]

Certainly a good question, and a thread that I'll continue closely.

Some years ago, I started on Scary Sharp and a granite plate. Seemed to cut fast enough, but the cost of the sandpaper added up quickly.

Next step: I "splurged" and went to a coarse \ x-tra coarse Duo-sharp that I used to flatten backs, flatten plane soles, establish primary bevels, and even flatten my Shaptons. And yes, it seemed to wear out quickly (no wonder!) - and as I increased my knowledge base - I wasn't fully confident of the flattness.

Further down the road, I moved to a Woodcraft slow speed grinder and a LV rest; it was quite a boon. Not a big fan of the hollow grind it produces, but the speed and flexibility that offers was worth it.

If I had my druthers, I'd go for the Derek Cohen approach using a belt sander inverted... But that'll have to wait.

Fast forward a year or three more, and I'm preparing to ship out to Afghanistan with my Platoon of Combat Engineers. I'm trying to assemble the most bare bones woodworking toolkit I can manage. I think about the best I can do downrange is to try the Dia-Sharp plates they have now (perhaps the x-tra, x-tra coarse).

- jbd in Bamberg

[David Weaver]

So is the hollow created by a 6" wheel easier to register on a waterstone than say an 8" or 10" wheel, or is the geometry insignificant in this regard?
Thanks


When they're fresh (the grinds, that is), it makes no difference. The hollow is just deeper coming off of a 6" grinder than it is on a tormek or some 10" wheel grinder kind of thing.

The advantage to that being that you might get an extra hone out of a given grind vs. a tormek (it's been too long since I used my tormek to hollow grind something on a regular basis, I can't remember how many times I'd hone a chisel before it had to go back to it).

For the amount of metal you remove (not a lot each time you re-establish the hollow) and the total time spent sharpening, I can't imagine that there is anything faster than a 6" grinder. A belt grinder will certainly remove material faster for the same level of temperature, but you don't get the hollow, and it's not quite as precise (which doesn't make much difference if you don't work all the way to the edge with a grinder).

The number of times anyone will burn something with a grinder will be too minimal for it to matter working with tools. My chisels and plane irons on a re-do of the bevel don't get hot enough that I can't cool them off just with my hand (instead of a dip cup).

[Bryan Schwerer]

To establish a primary bevel, I use a basic high speed Grizzly 6" grinder. I have removed the stock tool rests and wheel guards and use Ian Kirby's tool rest here.
http://books.google.com/books?id=tvYDAAAAMBAJ&lpg=PA71&dq=ian%20kirby%20grinding%20tool%20rest&pg=PA71#v=onepage&q=ian%20kirby%20grinding%20tool%20rest&f=false

You can make a set of jigs to hold your blade and if you experiment a bit you can make a line on a scrap board for all of the bevel angles to show you how far to extend the blade from the jig. Most of the time I just eyeball it.

It takes a bit of practice, but I keep getting better and better results.

[Michael Peet]

I use a 6" grinder with a homemade tool rest similar to the one referenced just above. It is far and away faster than my old method of coarse sandpaper on plate glass. Be careful not to catch a corner...

Mike

[john brenton]

You'll want a grinder, especially if you're going to be refurbishing any old tools. It's one thing to do some light shaping and maintenance, but if your refurbing old tools you'll eat your stones up.

[Mike Allen1010]

Thanks Lot guys. Your experience and feedback is very helpful. A couple clarifying (I hope) questions:

1) electric grinder- seems like the fastest way to go. Part of my hesitation is I have bad memories of using the grinder growing up and ending up with bevels not even close to 90 degrees; do I need a jig? How hard is it to learn to grind a straight edge (or intnetkonL camber)?

2) I have limited space in my shop for grinder- for the granite/sandpaper guys- how long does it take to put primary bevel on 2" wide plane blade? ( are we talking 10' or half hour?). Do you use regular silcon carbide sheet paper, belt sander paper or some of the more specialized 3M abrasive films?

Thanks a lot. I really appreciate the time/$ your collective experience is saving me.

All the best, Mike

[Mike Allen1010]

"I acquired the HF slow wet grinder (http://images.harborfreight.com/manuals/95000-95999/95236.pdf) at one of their sales. I don't think they carry this model anymore.

Zahid, I have a wet wheel horizontal "grinder" too. It's by Makita and about 25 years old. So have Ny suggestions bout where I could get a coarse wheel? What grit is your wheel and how long does it take you to grind a primary bevel on a 2" plane blade? I must be doing some thing wrong b/c it takes me 30".

Thanks, Mike

BTW- I really enjoy the interviews and FAQ info you out together- thanks!

[David Weaver]

1) you only have to rough grind close to square one time. the rest of the time, you're just grinding to an edge that's already in use. Same goes for camber - if you want to do coarse camber on a grinder, scribe the line into the back of the iron after you color it with dykem or magic marker or something and just grind to it.

If you have a very bad iron and you just want to get to a good starting line, then scribe the square line on the iron/chisel back from the edge just a tad and grind to your scribed line.

After that, maintenance grinding really doesn't involve a lot of that- your squareness will be determined by honing, so it can only get out little bits.

Very easy to check with a small square, even a shop made one out of wood since it's not critical measurement.

[Jessica Pierce-LaRose]

I haven't had too much of a problem grinding out of the shape that I want, be it square, skewed or cambered. Using the electric grinder, if something is out of whack enough, (like a filletster plane that's honed at the wrong skew angle, or I want to make a different amount of camber on my jack plane iron) I'll scribe the back of the iron with the line of the desired edge using a marker or layout fluid with a line scribed, and then grind the blade square to that shape. That line gets set just a hair back from the current edge - I'm not grinding off all the bevel that's there or anything - just blunting off the tip a bit. Then I set the toolrest to whatever angle I'm grinding at, get things set well and start working at it. As I start grinding, once the grind marks begin to eat into the squared off portion of the bevel, I can start looking at that glint of light from where I squared it off first, and see how things look - is that squared off edge still thicker on the left hand side than the right? Maybe the middle's a little thicker. If the squared off edge is perfectly the profile I want, then if I can make the whole thing dissapear perfectly, and at the same time in the grinding, then I've kept whatever shape I wanted. Hopefully this makes sense....

[Jessica Pierce-LaRose]

FWIW, for anyone interested in grinding w/an electric dry grinder who has a bit of trepidation on the subject - besides just suggesting jumping in, (after crowning your wheels) it's not that scary, two sources that might be helpful are by Joel Moskowitz's (of Tools For Working Wood) article from FWW 198, and Chris Schwarz's recent "Grind, Hone, get back to work" Video from popular woodworking.