Sharpening with sandpaper vs. other systems
If you’ve upgraded to bench stones or some other sharpening system, in what ways is it better than using sandpaper on glass?
I started out using honing film on glass, which worked wonderfully. When that got used up, I looked for something that wouldn’t have to be mail-ordered, and switched to wet-or-dry sandpaper, using spray adhesive to glue it to the glass.
The honing film was better in that the abrasive lasted a long time, the film was tough, and the pressure-sensitive adhesive was much more convenient than spray adhesive. (Although, spray adhesive is no longer a disadvantage of sandpaper. I finally realized that wet sandpaper doesn’t require glue!—the water holds it to the glass. Duh.)
I’ve pretty much ruled out brittle stones (sooner or later, I would drop a tool on it or knock it over onto the concrete floor). Are diamond stones shatter-resistant? And why do some diamond stones have a polka dot pattern, while others are homogeneous?
Janet
Replies
I still use sandpaper on phenolic sheets. I buy the rolls from McFeely's. I final hone with diamond paste on mdf. I do this so I can have a fairly long wide surface to work with. I own the largest diamond plates DMT makes and they are too short and marginally wide enough for me to comfortably sharpen the blade for a number 8 plane on. I use a Veritas jig for plane blades to assure a consistent angle, and I like the long setups so I can do long strokes.
They make (maybe its made now), a special sanding disk adhesive that you apply to the surface and then you can install sandpaper and remove it five or six times before a new application is required.
The honing film is still available, look for it online at knife making supply sites.
The diamond plates are metal (at least all I've seen), and are pretty much indistructable. Some have the dot pattern to minimize the amound of nickel and diamond required to coat the metal. They seem to work just as well as the solid surfaced plates.
Diamond stones and polka dots
Sorry, I forgot the part on polka dot/non polka dots. Being Swedish I am biased towards anything related to polkas:)
Seriously though, the polka dots are there to help clear the swarth (the yucky stuff that forms from grinding the edge) while you are sharpening. They are particularly helpful when you have something long or wide in contact with the stone, like a chisel or plane back or a wide chisel/plane edge. They are unhelpful when you have something narrow lke a mortice chisel or pocket knife in contact with the stone and you keep catching on the edges of the holes. Most polka dot stones have a section with no dots where you can do the narrow stuff on for that reason.
I would avoid dropping diamond stones. They are mostly flat enough (though not perfect) as is, dropping them could knock them out of kilter a bit. Actually not many things in the shop are improved by dropping them:)
re: Dropping
I've tried dropping hints to friends and relatives about tools they could buy me as gifts. That hasn't been overly successful, either. ;-)
Too true. Another Christmas has come and gone and nobody picked up dropped hint #1: "Any tool from Lie-Nielsen."
Although I was pleased to receive a pound of bismuth.
Janet
Too true. Another Christmas has come and gone and nobody picked up dropped hint #1: "Any tool from Lie-Nielsen."
Although I was pleased to receive a pound of bismuth.
Janet
Other systems
I confess, I have used about every method there is to sharpen, all the normal ones (sandpaper, oil stones, water stones, diamond stones, belt sander, fast grinder, slow grinder, hand powered grinder, water cooled grinder, leather wheel, abrasive on block of wood) to some "field" ones (concrete floor, rocks on the beach, toothpaste on wood).
I tried the sandpaper and flat surface method after seeing it in the magazine a few years back. I must say I didn't particularly care for it; "despise" might be a better word actually. I was always gouging and tearing the sandpaper, it wore out quickly, it was hard to ease the corners of smoothing plane blades, it was messy, and other things I care not to remember. I am not saying it is a bad system necessarily; there are those who love it. I just found it a pain in the tailfeathers compared to other methods of sharpening. It is a easy and cheap way to start out, although I don't know that most people stay with it once they have other options.
I personally use a combination of a Tormek (got an unbelievably good deal on it), diamond and water stones. I set the primary bevel with the water stone on the Tormek. For the initial back flattening for chisels, I sometimes do use sandpaper, if the back is way out of flat or pitted, otherwise I use a fine/extra fine diamond combo stone; plane blades blade backs I just do on the diamond stone since only the last 1/8th inch needs to be shiny flat. I set the secondary bevel on a 4000 grit water stone, and then do a quick hone with the leather wheel on the Tormek and the honing paste. When the secondary bevel dulls I clean it up with the waterstone or the diamond stone and then water stone if the edge is really worn or chipped, and then hit the honing wheel again. I use the guide for the Tormek stone, everything else is done freehand.
That said, I wouldn't necessarily recommend the above method to everyone due to cost; I just happened to pick up all the equipment on the cheap.
To upgrade from sandpaper, I would say start with a combo waterstone 1000/4000 or something similar. They aren't too spendy and they last a long time. Don't worry about dropping the stone, just find a safe place to sharpen and keep the stone there. I actually did drop my waterstone on cement; the two sides just broke apart and I am still using it. I would keep using the sandpaper to set the primary bevel rather than using coarse waterstones. They wear quickly and you don't need to set primary bevels all that often. Save your money there for a slow speed 8" grinder. I would say use a honing guide on the sandpaper or grinder; I still do, as it is difficult to keep that wide of an angle flat. Do the backs with sandpaper and maybe touch up the edge end with the 4000 side of the stone. (One more confession, I just keep the stone on the bench butted up against the Tormek and dump some water on it before I use it, not surprising I knocked it off the bench. There are smarter ways of doing this:).
Use the stone to set the secondary bevel, really just a matter of setting the blade on the stone on the primary bevel and lifting the back a little bit so that only the edge touches. Hold the blade at a diagonal to the stone (easier to keep it steady) and do some figure 8s. Turn the blade over and rub the back at the edge a few strokes to remove the any burr on the edge. If it is a smoothing plane blade; drag the edges on the stone a bit to keep the blade corners from digging in the wood. It takes a little practice, but once you learn to freehand sharpen, you will never go back. You should only be on the stone for 30-60 seconds for a simple sharpen after you get good. Any longer and you are just wearing your blade and stone. If the edge gets nicked, you can clean it up on the coarse side of the combo stone, otherwise just clean up the secondary bevel as it wears using the above method. When it takes too long to hone quickly (or if the tool is dropped or the edge gets mangled) reset the primary bevel on the sandpaper or grinder.
The stone will get a little dished eventually (no matter how careful you are about your figure 8s and using the whole stone) it is easy to flatten with coarse sandpaper on a flat surface.
4000 grit is good enough for most things. If you need sharper, you can hone with compound on glass/wood/mdf, whatever works. You sound like you have that well in hand already though.
Diamond stones are by no means necessary but they are handy for things like flattening backs, cleaning up nicks, and especially honing scraper edges.
In short, don't be scared of waterstones; they are great! That and electricity can take some of the tedium out of sharpening:)
Diamonds are Forever....
Hi Janet,
I've tried waterstones, sandpaper and now diamond stones. I have 4 "stones" where two of them are double sided for a total of 6 grits. After that I use the leather strop loaded with compound.
I used the sandpaper for a long while and discarded it because it kept ripping.
Waterstones needed more maintenance than the diamond stones.
Diamond stones are expensive but I expect them to last a long time and also save me a lot of time not having to flatten them. I'm thinking I want to get another grit or two between the last two grits I have.
But electricity is easier and faster
For the cost of two decent diamond stones, you can get a 1725 rpm grinder. Just something to think about.
I use diamond stones to touch up edges also, since they don't dish like waterstones, but they are still fast . I do hit the waterstone briefly after the extra fine diamond stone because diamond stones don't go fine enough, though. Since the waterstone is just used to clean up the diamond stone scratches, it stays flat a long time.
I do primary bevels on a grinder, as it suits my patience level better:)
Consult with Professionals
Look for professionals advice. If you are in Austin, TX then, Austin Furniture Repair is the leading one company there. They might help you with good information and expertise.
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