Established edges on my tools all get sharpened & honed by hand with a Veritas jig, diamond plates and/or micro-grit papers on float glass. But I seem to have acquired a lot of spare blades, many of which need radical re-shaping really. I can do this on rough diamond plates by hand but it can take an age to grind back some of the wider plane blades. ……So I’m considering a sharpening machine. My question:
Is a grinding wheel or a grinding belt machine preferable?
Or to put it another way:
Is a re-shaped bevel made ready for sharpening/honing better as a flat or a concave shape ?
Another question:
Does anyone have experience of the Robert Sorby proedge machine ?
Thanks in anticipation for any advice or useful comments you can make.
Lataxe
Replies
I would avoid belts because they can mush around corners a bit in use, rounding off the edge even used against a platen. I have a 10" slow speed wet grinding wheel for re-making edges. I like the concave because I can hand work a primary bevel on my diamond stones balancing on the tips of the hollow before switching to a jig for the Shaptons and final polish.
I switched from a grinding wheel to the Veritas Mark ii. With the coarse paper it will establish a primary bevel quickly and you can continue to finish hone with the system, using different grit and platen. It works great but I changed to Shaptons for secondary and tertiary bevels as the finer grit discs are pricy and wear quickly. With the stones you can do a quick hone many times quickly before going back to the primary bevel / re grind
I grind with a Baldor 7" low speed grinder, then hone with Shapton sharpening stones. I was taught to hollow grind, then free hand the honing, so this combo works well for me. I also have a WorkSharp grinder, but I only use that to flatten the back of blades.
Tormek T-8 has served me well for my sharpening needs. It was difficult to justify at first because the cost is quite high. But with the versatility and different jigs I can sharpen nearly all my own tools. About the only things I don’t sharpen are my sawblades and router bits.
Thanks all for the replies so far.
I did have a Tormek for many years although I ceased to use it for the straight blades as it seemed to take too long to reshape them, was rather messy and weighed a ton. (I had to put it away and take it out again because of lack of bench space or floor space for a dedicated station). It certainly works , especially for gouges and other non-straight blades I found difficult to sharpen by hand. They've gone up a lot in price and are now very expensive. I sold mine for substantially more than I paid for it after having it for 10/11 years.
I have re-shaped a plane blade or two with coarse 3M papers on float glass using the Veritas MkII jig. It's OK for "mild" reshaping such as re-doing the same bevel angle already there to take it back beyond the accumulated secondary bevel sharpenings of a degree or two .... but I calculate it'll take a long, long time hand grinding to, say, make a 25 degree main bevel on a 2 1/4 wide blade with a rather large 40 degree secondary bevel on it. In fact, I know it will as I started one and gave up after 40 minutes and not much progress!
Making a hollow bevel on a grinder wheel would allow me to hand-hone the thin cutting bevel on the main bevel .... but I prefer the Veritas jig to establish very small secondary bevels of +1 degree or so on the main bevel. I'm sometimes cack handed and it wouldn't take much for me to hand-hone something clumsily such that the main bevel would need re-establishing.
A slow speed wheel grinder with a coarse grit CBT wheel is tempting. But most of these grinders seem not well made. In particular they seem to come with tool rests that don't really offer much except a wobbly or slipping flat platform. So you have to factor in the cost of something like that Veritas or a Tormek version - add another £70 - £100. In addition, CBT wheels are very expensive - £99 - £130 here in Britain.
That Sorby proedge attracted my eye as its sanding belts come in numerous grits of numerous grades and are inexpensive - around £10 each +/- a couple of quid - except for the diamond versions which I won't be wanting. The machine comes with proper tool rests to which inexpensive additions can be mounted to sharpen all sorts a la Tormek. It also comes with two rough grade belts that remove steel rapidly - which is what I basically want my sharpening machine to do.
But I'm still open alternatives, if anyone can make a good case for their solution. I'm not in a hurry to buy anything. :-)
Lataxe
CBT wheel?
If you meant CBN then no to that. Bad idea. Very bad.
CBN is great for sharpening HSS tools but countless stories (and manufacturer advice) suggest it will fill with crud if used on tool steel such as chisels. I have two grinders - a small white soft stone for most tools and a large CBN set up with a Kodiak jig for turning tools. (shout to Woodturners Wonders who even post to NZ!)
I have never used a ProEdge but Sorby tools are all well considered. It will undoubtedly work pretty well, though TBH, I would not buy it.
I have lapped a whole bunch of old chisels given to me by a relative on a series of diamond stones and then sharpened with the small grinder and veritas jig, like you.
TBH, I don't think it makes the slightest different how you grind because in the end the cutting edge is always refined on stones.
Given that grinders are cheap, versatile and easy to set up, I'd personally not see any value in change.
Rob,
Yes, CBN wheel - a slip o' the typing finger.
I did read that CBN wheels are meant primarily for very hard steels such as HSS but the seller blurb warnings about clogging mentioned only soft metals such as aluminium or copper. Here's their full blurb on the subject:
"CBN wheels are at their best when grinding HSS steels as well as powdered metal and hardened carbon steels. This makes them invaluable for maintaining the edges of woodturning tools and other hand tools. Whether it is bevel edge chisels, screwdrivers or drill bits, CBN is the best material for grinding hardened steels. Attempting to grind unhardened steel or soft metal such as aluminium, copper etc is detrimental to performance and results in a clogged wheel".
My chisels and plane blades are all around the 60 hardness +/- a little bit. Scrapers are softer .... and perhaps some Marples blue-handled chisels. ......
Do you have any url pointers to cases of the CBN clog? I'd be very interested in reading real world experiences rather than advertising blurb. :-)
I do intend, like you, to refine my edges on (diamond) stones; also on scary-sharp papers on float glass, as I do now. And a leather strop. But there is a long list of items needing a serious re-shaping via significant grind so the method I use will make a difference - but only to the amount of time it takes.
I've already bored myself silly hand grinding an A2 plane blade in an attempt to bring it back to a full 25 degree primary bevel from its present condition with around 3 mm of 40 degree secondary bevel at the cutting end. Still not done after ages and ages of to & fro in the sharpening jig on the roughest diamond I have (a savage 140 grit).
Lataxe
Clarification, when I mentioned the Mk ii, it was the power sharpening system. I too used the scary sharp before going to this. As noted, I prefer the stones for quick secondary, and secondary tune up. I just found the 3M 9micron of late does not last. Likely you have looked at it, but in case you thought I was masochistic enough to flatten and bevel using the roller jig on paper.
I have been using a 360 CBN wheel for a couple years and it’s my go to wheel 90 % of the time for carbon, hss and powdered metal tools. No sign of cloging and still as agressive and Clean as day one.
I use a slow speed Rikon grinder with the stock white wheels for setting up a hollow. It's an 8" wheel so getting a hollow is almost a trick of the eye - one would think a 1" wheel would make a better hollow. But it's possible to do. It's a little rough (the hollow) but I don't really care about the texture of the hollow, as it's the bevel I set later that counts.
I use the Veritas deluxe sharpening jig and a variable set of coarse diamond stones (300 and 600), then oil (Arkansas 1200) and water stones (up to 8000) to get a nice edge. Some like to go to 12000 grit but I find that not necessary. I then strop on leather with three grades of strop grit and it's easy enough to accidentally cut myself just by moving my hand too quickly near the business end of the chisel/tool. Edges seem to last a goodly amount of time depending on the quality of the steel.
For a quick re-sharpening I just whip out the water stones - I keep them in a lidded plastic container filled with water so I don't have to re-soak them which is time-consuming when using water stones.
I've looked dreamily at the Tormek setup and other setups but this works well for me and I can hear angels sing when I start to use my freshly-sharpened hand tools. :)
Clogging on grinder wheels is a hazard for soft metals such as brass, no matter what the wheel is made of. But CBN is great for tool steel, no matter what alloy.
Update.
A Sorby Proedge was my choice for grinding plane and chisel blades, after looking at loadsa other machines, mostly wheel-based bench grinders. The Sorby is also doing some drawbore pins (making pointy ends on 3 diameters of bar stock rod-pairs for fitting to shop-made handles). Before too long, the ladywife will be sharpening up her many kitchen knives on it, when the jig comes.
There's a thread in the Robert Sorby forums in which I'm relating my experiences with the machine, including the glitches - should any other actual or potential Proedge owner care to look or participate.
https://robert-sorby.freeforums.net/thread/232/proedge-techniques-cabinetmakers
Lataxe
I'll provide another thought here; though, I'm the first to say that I do not have a system to get ultra-sharp edges.
My primary approach is that I refresh my sharp edges, rather than wait until they're down-right dull. The difference here is that for dull tools, you need to re-shape both primary and secondary bevels (significant material) as well as re-flatten the bottom of the chisel. This is too much material, and related effort, for manual (scary-sharp) sharpening. For refreshing chisels, I use sandpaper to 2,000 grit (with a Veritas Mark 2 jig); then, DMT diamond thereafter (with a sharpening compound).
I've owned the Tormek (the machine was excellent, the stones not so much) and the Work Sharp (sent it back); and decided to sharpen more frequently with sandpaper and Veritas.
I don't like sharpening stones, mine never seem to remain flat, and I don't want to compound the process by having to flatten stones to sharpen chisels.
Use of a leather strop with some honing compound can bring back a slightly dulled scary-sharp edge to usable sharpness as long as the edge is just skimmed over the leather rather than pressed into it, which can dub the edge. I typically get 3 leather hand-stropped revitalisations of an edge before the micro bevel needs re-establishing.
Re-establishing the micro bevel takes about 5 minutes - to load the tool into the Veritas MkII jig and get out then put away the glass plate with the scary sharp papers on it. RUbbing the bevel on the papers takes about 10 strokes per piece of three different grades of 3M paper. I have the necessary angles recorded for every tool blade in a small black book. :-)
A micro bevel can be maintained like this for some months, if one is a hobbyist rather than applying the tools eight hours a day every day. Eventually it gets too large and re-doing it takes too long. This is the time for re-establishing the primary bevel then a new teeny micro bevel. A grinder speeds up the making of a new primary bevel, I've found with the Sorby. About 5 minutes including three belt changes from coarse to fine; then another five minutes to make the new micro bevel on the scary sharp glass sheet.
I never need to re-flatten or re-polish the back of the blade as this stays flat/polished after doing it the first time when I first get the tool. The wire edge needs removing after re-sharpening the bevel .... and sometimes a chisel back will get a scratch from something that can be polished out if it goes as far as the edge.
****
I had a Tormek for years, for carving tools and even planer blades. I do very little carving, though; and the planer blade jig worked but took ages to sharpen two ten inch blades of HSS. I sold it because it was so slow at taking significant metal, no good for the finest of edges without an additional very expensive wheel, wet-messy and weighed a ton. It was also a pain having to re-flatten the wheel edge after using it on a gouge or other non-flat blade.
Waterstones get a good rep but its too much mess and mucking about re-flattening them every time they're used.
I like the Sorby as it's very quick at re-forming bevels and seems very well made, unlike most wheel grinders. The tool rest isn't a perfect design but it can be tweaked to work very well so you don't need to buy another expensive one. The spare parts (such as bearings, wear plate and so forth) are very inexpensive compared to the spares sold for most machines, which can often be a rip-off of the captive customer. The belts are inexpensive - about £5 or $8 for ceramic or zirconium, which are said to last a long time and never need re-flattening
Lataxe
8 inch coarse (80 grit) grinding wheel with a crowned profile will help get you good quick results. The crowned surface helps prevent overheating and gets fast results. Set up your profile angle and once the surface is profiled it's off to the stones. This whole process of refurbishing new cutting edges is easy and quick. Check out a couple of Cosman's video's for guidance.
I’ve used a lot of systems but have always come back to (1) hollow grind on an 8” white stone high speed grinder, using a Veritas tool rest; (2) refine on Japanese water stones, 600 then 2000 grit; and finally (3) strop on a good flat piece of leather with alumina powder then rotten stone. As far as the backs are concerned, I flatten them on the water stone. The flattening takes a while but only has to be done once, when you first get the tool.
BTW, I lusted after the Tormek system for years. I finally forked over the money (and its a LOT) for the grinder and a bunch of jigs, and really tried to make it work for me. After about a year, I finally gave up — it’s just soooooo slow, and doesn’t give as good an edge as the above. You live, you learn.
This forum post is now archived. Commenting has been disabled