Should a granite lapping/surfacing plate with wet/dry sandpaper be okay for flattening honing stones?
Anyone seeing this use one?
Anyone seeing this use one?
Thanks - I would think that as long as nothing gets between the sheet of abrasive and the granite it won't be an issue. I find the motion of the stones stay completely on the abrasive sheet which mostly covers the plate. A film of water between the plate and abrasive sheet and a couple of fingers on the edge of the abrasive sheet keeps it locked in place.I would be careful when using a granite surfing plate with a stone that is known to shed grit particles. Any loose particles of silica dioxide or aluminum oxide (the main components of natural Jnat stones) will cut steel and or stone. Laying a stone to determine flatness is one thing on a granite plate is one thing, but using a grantie plate as a tool/surface for flatening a third-party stone will create a 3-part abrasive scheme and all you will end up with is a concave part 1 and a convex part 2. The plate surface will usually deform and become undependable.
Honing a razor or knife is an exercise in give and take, stone vs steel, all winning is a compromise.
Alx
Thanks - what are the specifics on the abrasive sheet you're using?It works very well. I use this system and it is much more accurate than most of the diamond plates out there. The only diamond plate that comes close is the DMT diaflat. One thing to bear in mind is that these granite plates are very heavy. It may not be the most practical solution because it is very bulky. It does give a nice big working surface though. It’s also nice for finishing stones and adjusting the surface prep of things like arks since you can fine tune the grit. It’s a great follow up to the DMT diaflat which is fast and rough. I’ve found the two systems to agree within a very tight tolerance.
I use double sided tape to hold the edges down. You do need to be careful to not let slurry spill over the edge of the paper but it’s pretty easy if you’re careful. If you want to be safe you could fully tape the whole side. You can also put loose sic on top of the sandpaper to get more life out of each sheet. Just be mindful not go through the paper. It takes a long time but after a while you will see the paper showing through. This happens faster on the finer grit paper.
If you mop up the slurry up with paper towel before removing the sheet you won’t spill any slurry onto the stone. It’s worth picking up a few rubber blocks at the hardwear store to put the stone onto. It holds the stone in place and will stop it scratching up any surfaces. It also makes it easier to get your fingers underneath when you want to pick it up again. My small-ish stone weighs 10kg.
Wipe any dust off the back of the paper before putting it onto the stone. Stick the paper down with double sided tape to stop it sliding around. Make sure that you don’t get any slurry under the paper. If you do that you will have a very accurate and versatile system.
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3m Silicon Cardide Wet Dry Sandpaper.Thanks - what are the specifics on the abrasive sheet you're using?
Atomas are good quality plates and very user friendly. No agreements there. I have a couple and they are by all means good enough for the job of lapping razor stones. That aside they are far from perfect and you can almost certainly get a stone flatter. For a soft stone that you use with slurry it probably doesn’t matter. For a hard stone like an Ark it might be worth the trouble.I Lap everything with Atoma plates and check flatness with a Starrett straight edge.
Stones are flat, always. They're not going to get flatter lapping them any other way.
At one time, when I had a literal ton of Arks to lap, I considered getting a 6" wide granite reference plate and cutting it down to 9-10" long.
But it would still weigh 13 lb, more than I wanted to deal with. I always lap under running water so the granite's corners would have prob wrecked my sink. I wound up killing the back of a dead 10x3 DMT Diafine instead.
You guys crack me up. As if a piece of sandpaper is even close to flat, if you are measuring to that degree. You could start with the flattest surface in the world, the moment a bit of paper with sand glued to it is put on top, all bets are off.
But it's still close enough.