Hi:
I was flatenning the back of a chisel this weekend. Using sandpaper up to 2000 grit, I had a nice shine going on the back with all the fine scratch marks running parallel to the chisel. I pulled out my 6000 grit waterstone, flatenned it, and rubbed it with the nagura stone. After using the stone, the chisel wasn’t as shiny as before but looked gray. I’ve had this problem before. Any ideas on the cause? The solution? Does it matter?
Thanks in advance.
Replies
I'm not sure about this, but the 2,000 grit sandpaper might be a finer grit than the 6,000 waterstone. If so, you're actually creating deeper scratches with the waterstone, thus dulling it or causing it to lose luster.
In any case, the 2,000 grit sandpaper and the 6,000 waterstone are NOT the same measuring scale.
Mark, how do I find more information and a concordance for the different scales? Should I stop at the 2000 grit sandpaper?
Thanks.
I once saw an equivalence scale but can't remember where. I bet someone posts one here. My rough sense is to agree with the post that says 2,000 grit sandpaper is about the same as an 8,000 grit waterstone.
You can definitely stop at the 2,000 grit sandpaper. Then, as BG says, put some of that green compound on a flat piece of wood (I just use a scrap of plywood clamped to the bench) for the final honing. You'll get an extremely sharp edge.
Here's a grading comparison, sourced from Leonard Lee's The Complete Guide to Sharpening Taunton 1995, Appendix 2.
60 micons = 220 (US Industrial mesh) = P240 (European) = 240 (Japanese JIS Grade) 50 = 240 = (?) = 280 40 = 280 = (?) = 320(?) = 320 = P360 = 360(?) = 360 = P500 = 400 30 = 400 = (?) = 500 20 = 500 = P1000 = 600 15 = 600 = (?) = 1000 (?) = 800 = P1200 = 1200 12 = (?) = (?) = 1500 9 = (?) = (?) = 2000 5 = (?) = (?) = 2500 4 = (?) = (?) = 3000 3 = (?) = (?) = 4000 2 = (?) = (?) = 6000 1 = (?) = (?) = 80000.3 = (?) = (?) = 10000 (?) means there is no equivalent listed.
Unfortunately it is really take a guess as to what 2000 paper is equivalent to. The first question is: are we talking US or EU standards? FWIW, my guess is that 2000 paper is graded in accordance with the EU standard, and its grit size is about 5 micron equivalent to a 2500 water stone
I knew someone would provide a list! Thanks.
I'm pretty sure that 2000 grit sandpaper is higher than 2500 waterstones, in fact I'm pretty sure it's above 6000, just because I've used both pretty regularly. I'd say around 8000, but my impression is purely non-scientific and I wouldn't bet anything on it. When I used sandpaper for sharpening I went from 2000 to the green compound and now that I use waterstones I go from 8000 to the green compound, and my impression is that they're about the same.
I'll admit I don't know. I've a 6000 water stone and an Ultra Fine ceramic whet stone made by Spyderco. My impression is that the ceramic stone is finer than the water stone but that may be more related to the difficulty of raising a slurry on the 6000 stone.
However, the Japan Woodworker catalogue suggests that a 10 micron 3M diamond stone is equivalent to 1800 grit5 micron Microfinishing film is equivalent to #2500 0.5 micron is equivalent to #9000
Who do you believe? at least the last one is the same as Leonard's equivilancies.
Those numbers look about right to me, with .5 micron equal to a 9000 grit waterstone, if I'm reading it accurately. Do you know the micron size of 2000 grit sandpaper?
Sorry I don't. However, I've got a couple of sheets of 10, 5 and 0.5 micro finishing film and some 2000 wet and dry. I'm don't know if the wet and dry is US or EU standard. My impression is that the wet and dry is, to touch, about equivalent to the 10 micron film.
How does it perform?
That is the only important question...
Mark..
Did you work up a slurry on the stone with the naguna before polishing?? It's the slurry that does the cutting. I'm guessing that the blade went gray because the scratches have been randomised... Either way, it should have left the steel with much finer scratches than the 2000 grit paper left.
Mike Wallace
Stay safe....Have fun
Mike - so you don't think that the scales are different, as Mark does? Why would the scratches have been randomized? I used the same technique for both. I did get some slurry going, perhaps not enough.
Thanks.
I can't say for sure if the scales are on a par.. but if they're not, they're very similar; I can feel a texture on 2000grit paper... I can't feel a texture in 6000 grit slurry...by definition it has to be finer...
I wouldn't worry too much about it, but if you're determined to get that mirror polish back, try again with a heavier slurry, remembering to keep it wet. The backs of my blades aren't anywhere near mirror polished, but they get progressivly finer with every sharpening; after re-honing the secondry bevel I give the backs a wee tickle while the stones are on the bench. I get shavings I couldn't dream about while using my old oil stone... Just for the record, my secondry bevels have a mirror polish... I figure it's related to the area you're working... the backs will get there in time. Mike Wallace
Stay safe....Have fun
Bake sale,
If you want shine....strop with some green rouge...wow!...and a great edge.
I have experienced this phenomenon. The 2000 grit paper is more equivalent to an 8000 grit waterstone. Both of which are down to a micron or two. That's fine enough. What matters most now is honing your technique in using the chisel.
Have fun!
Rick
waterstones leave a matte, uniform appearance early in the polishing process. When you progress through the grits and get to 6000 grit that matte grey usually progresses nicely to a mirror polish. When you back isn't fully flat, generally what you see is small areas that are polished (high spots) while nothing really happens with the low spots (dull grey). I think your high polish you obtained with the 2000 grit sandpaper is a bit of an illusion. It might look good but for some reason (I think it has to do with overall flatness and honing out all the previous scratch patterns) you're not quite at your goal. How did you prepare the back of the chisel prior to the 2000 grit paper?
I used the method described by David Chattsworth in a recent FWW for waterstones. Starting with 600 grit paper and worked up through 800, 1000, to 2000. At each point I worked until the earlier scratches were replaced.
I'm wondering if starting with 600grit paper may have been premature. What brand of chisel was it. Often times I'm working with garage sale socket chisels that need a fair amount of coarse flattening first. By using the sandpaper method you might need to start with 100 or 120 grit silicon carbide auto body paper and go from there. Also, just curioius: what are you backing the paper up with? I switched to a granite surface plate and I no longer use adhesive because the paper wears out too fast and peeling off the residue is too time consuming. Sometimes I use plain water, other times just dry. Also, be careful around the edges, if they curl up slightly, the will take slightly more off on the edge of your tool. I found that using polishing waterstones: 4000, 6000 & 8000 is more finicky but I like being able to rinse it with water at the kitchen sink and I don't have to worry about wearing out the sandpaper.
Good Luck Bake Sale.
6000 grit water stone is roughly equivalent to 1500 grit paper. Here's a chart showing grit size comparisons:
http://www.ameritech.net/users/knives/grits.htm
Michael R.
Knots is amazing. Someone always comes up with the answer.
If I'm reading it right, this seems to show that 1500 grit sandpaper is about equivalent a 6000 grit waterstone, and 2000 grit sandpaper is about equivalent to an 8000 grit waterstone. That's just about what I would have expected based on my personal use. As I said earlier, I formerly used 2000 grit sandpaper and now use an 8000 grit waterstone, and they seem about the same.
Of course, all that matters is that the darn things sharpen metal. But this might explain why the original poster experienced a dulling of the tool when we went from 2000 grit sandpaper to a 6000 grit stone.
It's not exactly equivalent, because the slurry on a waterstone continues to break down depending on technique, but for initial particle size it's a good comparison, I think.
Michael R
Mark
I agree with you from my experience with both. By taking an already worked chisel from 2000 grit s/p to 6000 grit water you are traveling in reverse. I stop at 1200 grit s/p and go to 8000 grit w/s and then strop with green jewelers rouge.
Before I figured this all out, I would go to 6000 grit stone and get the graying. The greying is not a problem as the only thing doing the cutting is the very fine point where back meets front bevel. If that is as it should be it is sharp.
I sometimes still get the grey. I suspect it may have to do with the reaction of the water and the steel. Don't know and doesn't matter to me as long as the tip doesn't reflect light. I look at it as "if you arrived, you arrived". ha.. ha...
Regards...
sarge..jtProud member of the : "I Rocked With ToolDoc Club" .... :>)
So you're one of those bi-sharpeners, eh? I've given up with the sandpaper for the time being because I got tired of replacing old sheets with new sheets, but now I have to worry about keeping the stones flat. Pick your evil, I guess.
Mark
Yep, burn both ends of the candle. I get flatttening quickly by laying one of those sheet-rock sanding screens down on the same piece of flat tempered glass I use for sandpaper. I have used 120 grit s/p and have done it with a concrete block. I find all to be simple and quick.
sarge..jtProud member of the : "I Rocked With ToolDoc Club" .... :>)
Just wanted to say thanks to everyone for their replies. I went back and stayed with the sandpaper. Nice shine.
"By taking an already worked chisel from 2000 grit s/p to 6000 grit water you are traveling in reverse"
Hello Sarge,
I have to disagree with you on this: a 4000 grit japanese water stone and a 2000 grit sandpaper have roughly equivalent sized abrasive particles at 6 micron size (see http://www.nortonconsumer.com/pdfs/GenInfo2004.pdf for a better comparison).
A 6000 grit Japanese stone lies somewhere between the 4000 and 8000 grit has particles sized around 4 or 5 microns. This of course is still an apples to oranges comparison in that sand paper cuts differently than a Japanese waterstone which has a different feel than a ceramic binder waterstone etc.
I think the original poster's problem is that he is mixing two different techniques and is probably using an uneven waterstone.
I do like stropping after using waterstones because it lets me get oil back on my precious metal tools ASAP!
I took care to flatten the stone with sandpaper adhered to glass prior to sharpening. If the 6000 grit water stone is truly smoother than the 2000 grit paper, I wonder if my problem was too much pressure?
My experience using both says otherwise, as does the chart that was posted earlier. But whatever works for you.
Hello Mark,
I got my data from Norton, look at the second page of the linked page. I would also point to Leonard Lee's book on sharpening and the electron microscope photographs of the stones and his comments about the effectiveness of waterstones. I do not know where the other site got their data from.
Busto
I along with Mark have seen different data submitted here. It leads me to believe that there may be some confusion created by printed charts of grit comparison by various sources. Before I saw the first chart, I assumed 6000 grit meant 6000 grit. I don't assume that anymore from experimenting with higher grade s/p. I have seen three different charts at this point and all have varied with their conclusion.
I replaced my 6000 stone with a 8000 and can detect a difference. What I still don't know and may never, is what the true comparison is. I posted a thread when I first joined Knots aboout two years ago concerning 220V versus 110V. Over a hundred posts (many EE, electricians, etc.) and none agreed totally. The Medical field is not an exact science. Three opinions may vary.
My conclusion here: Try the different grits of sandpaper and stones and make comparisons based on what you find. Whatever looks, feels and works best for you should be the logical direction to take with mixing the grits. The bottom line will still be the sharpness of the junction between back and bevel.
I base that decision on variance in printed charts. Is the Norton chart the same as King, etc. on the stones? Does a 3M s/p chart compatible with other brands? I personally don't know and have my serious doubts. Henceforth I could be decieved in my conclusion. But it is hard to conceal final results and that is where the checkered flag gets waved.
Regards...
sarge..jtProud member of the : "I Rocked With ToolDoc Club" .... :>)
Hi Sarge,
I am not trying to pick a fight, but rather to try to correct what I believe to be a factual mis-statement about various abrasive comparisons. Note that I never said that any method was better or worse than the other.
As you pointed out comparing "grit size" does not mean much as there are multiple grading schemes in different countries. But a micron (1/1000000 of a meter) is an absolute measurement so it makes more sense to use that as a comparison metric. What the Norton chart shows is the abrasive size of 2000 grit US spec sandpaper is the same size as the abrasives in a 4000 grit waterstone. A 6000 grit waterstone has smaller particles yet. With all due respect to the knife maker's site, I bet he was consolidating information he got elsewhere, Norton, a manufacturer of abrasives, actually went out and did quantitative analysis of abrasives.
And there is a lot more going on with how sharp an edge is than how shiny the surface is or what size abrasives you used in sharpening it are. Consider a circus mirror that is curved every which way but still reflects light perfectly. I wouldn't want the back of my chisels to be that kind of shiny!
Busto
I know you weren't picking.. It's just a discussion of views.
I have the cheaper stones King makes. Are they truly the same grit as Norton if placed side by side? Is 3-M paper the same as Norton, Klingspor, etc.? Do all the manufacturers follow strict tolerance guide-lines regardless of which 3 grading systems they use?
These are just a few questions that draw me to a conclusion that I should experiment with the product I have on hand and draw my own conclusions from the results that occur. I just have a feeling that like HP ratings on hand tools, there is a lot of gray area in there. I think the manufactures don't always use the same recipe and the results can vary. ha.. ha..
Have a good day... :>)
sarge..jtProud member of the : "I Rocked With ToolDoc Club" .... :>)
Pick a system. You don't need a sandpaper system and water stones too.
Hi,
Using Norton waterstones of 1000, 4000 and 8000, I get a matte grey finish on the 4000 which quickly turns to a chome type mirror finish on the 8000 stone.
Ken
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