I have just recently sharpened my chisel’s with sandpaper on a glass. It seems to be fairly sharp, but I was wondering if either diamond or a stone would work better or faster than sandpaper. It was wet or dry and I used 220 and 400 grit which gave good results but I dont know how they would compare with the earlier mentioned mediums because I dont have diamond or stone.
Thanks for the advice.
Replies
I sharpen my chisels with sandpaper also but I go to 3000 grit Mequiar's wet or dry sandpaper. Mequiar's grit is very uniform and seems to do a better job that others I have tried. Dimond stones will perform the task more quickly up to the finest grit available. I cannot help you with other stones because I quit using them long ago.
Garry
WoodWorks by Garry
I don't think one method is necessarily better than another. I have water sones,oil stones,diamond,and ceramic. Sharp is sharp and the grit determines the quality of edge. A stone in 220 grit will remove steel just as fast as sandpaper of equal grit. You might want to use sandpaper in finer grits also. a leather strop charged with abrasive paste will put the final "whammy" on the edge.
You can get also sandpaper in incredibly fine grits.
>> A stone in 220 grit will remove steel just as fast as sandpaper of equal grit.Only if the stone manufacturer and the sandpaper manufacturer used the same grit size standard. And even then, new, clean sandpaper will cut quite a bit faster than a stone for the first 20 or 30 strokes. New silicon carbide cuts like fury until it starts wearing a little.
Sounds like you're doing the scary sharp approach (http://www.shavings.net/SCARY.HTM#chisels). Many favor this, but I'm not sure that 400 is fine enough to finish with- you should really have a near mirror fiish when done. You might try adding a finer grit (auto parts stores have papers for metal finishing that are very fine), or, you could just end with a fine waterstone (~8000). This is also a good way to set your secondary bevel.
On the other hand, if you are able to "shave" softwood end grain (or the hair on your forearm, whatever) with the edge you are currently achieving, you might not need anything else.
Glaucon
Yes I have heard that if you can shave with a sharpened edge, It's good. But the super fine grit of 8000? That seems rediculus, but I am going to try it, along with honing the chisel, because my method is not sharp enough for what I think and the problem is tearing the wood, and making a mess, so the best thinf is to spend time before instead of time after trying to fix the mistake.
Another thing I am trying is sharpening my hand plane in this way. Since I am not satisfied with the results, I need a sharper edge, so do you sharpen your planes the same way you sharpen your chisels?
B Near
8000 is if you are using a waterstone. I usually do 1000, 4000 then 8000. If you are using sandpaper, it's usually 220, 400, 600, 1000 then 2000 (I'm not really sure about the conversion factor between waterstones and abrasive papers). It takes less time for each grit of sandpaper (20 or 30 seconds) than using stones. You do need to brush away the grit with a brush or compressed air between each grit. You can do plane irons this way as well- I think of a handplane as a mounted chisel. Where you start depends on the condition of the tool. If I were tuning up a plane iron from a flea market, I'd start low, ~100 on paper (this is one job that a coarse diamond stone does particularly well). If you are touching up an iron or chisel that you've previously tuned (and haven't abused) you will probably only need to do the last 2 or 3 paper grits. If you do use paper, make sure that your surface is true and flat. Lee Valley sells optical glass for this purpose- you can use granite or a similar stone as long as you are sure that it has been ground flat.
Glaucon
As DONC4 said, honing with a leather strop is a must. No matter what grit you end with, honing will make the edge just that much sharper and last much longer. I constantly hone my chisels while chopping and rarely have to sharpen.
I used to just go to 4000 grit Norton water stone, but until I saw someone else hone (Jed Dixon at the Northeast Homebuilding Show) I never knew what a difference it would make.
With that said, I also agree with Glaucon, that you should at least go up to with automotive paper if you want a really honed finish. I used to use this method, using WD40 as a lubricant, I now use Norton Water Stones. Personally, I plan to switch to diamond stones with a final hone. Water stones require you to constantly flatten and soak the stones which is a messy process.
You'll find all kinds of opinions here on sharpening, but no mater what method you choose, I'd say that a final honing is the most important step.
Jim
Coventry Woodworking
Knaughty,
There is no right or wrong answer here, I have tried the whole spectrum and some times I still change my ways from one to the other. My latest preference is starting off with a heavy grey grinding wheel to get the initial chisel shape (not very often), then follow up with a wet grinder to smooth the bevel, then go to 1000 water stone, then a 6000 water stone. I also use a 4000 water slip stone, to put a micro bevel on the inside.
Once this is done, I stay with a buffing wheel installed on a grinder, using a medium compound, for a long time, before I have to go back to the 1000 stone. Fifteen seconds on the buffer, and I can shave hairs without the chisel touching my skin.
Again, it's all about personal preference.
What do you mean by a buffer? Are those wheels that go on bench grinders like grinding wheels? If that is so, I will try to find me one and get the best edge I can. I always value advice from ones with the experience.
B Near
That is correct, I use a 8" spiral sewn buffing wheel on my normal bench grinder, with a medium compound. I notice Lowes now also sell buffing wheels and compounds. My investment was about $12.00.
You have to use light pressure, so as to not round the bevel and hold the chisel with the cutting edge pointing down close to the bottom end of the wheel, keeping only the bevel in contact. About 15 seconds is all you need on a properly shaped bevel.
Ok, thanks for the input and I hope to have a sharp edge soon.
I think the bootom of the chisels need flattenning and I also need to put the sharp edge at a 90 degree angle, which it isn't tight now.
B Near
When you flatten the bottom of the chisel, stick and hold on to a strong magnet placed on the chisel. This will give you a "handhold" while you are moving the chisel across the stone/sandpaper. I got my magnet from an old speaker for free.
Knaughty,Mayhap I'm imagining this, but I believe there is an "unintended benefit" of sandpaper-on-glass, where the paper backing of the sandpaper slightly compresses during the sharpening process, causing a very slight radius to the blade, or at least, the corners get worked back a little more than the middle. Anyone else notice this, or have I been sniffin' da varnish? I've acquired DMT diamond stones, and for much of the basic work, they do just fine. I use the medium DMT to dress the water stones, so I'm able to keep relative flatness of the water stones.I bought a finishing stone from Japan Woodworker (Product ID: 02.098.10, Green Bamboo polish Water stone- no, there is neither green bamboo nor pandas included in the kit), which puts an amazing finish on irons and chisels. A nagura stone is included with it, used with great effect on the green stone and the Norton 4000 and 8000 I also own.The Norton 8000 seems to be fairly hard, and it just doesn't make a lot of slurry as you work it; nagura-stoning it is a must. The green stone feels a bit softer, and tends to get a slurry going much faster than the Norton.Cheers
Knaughty,
I sharpen with only sandpaper and glass and I am very satisfied with the results I get. With something new, I go 220, 400, 800, 1000, 2000. For subsequent re-honings I skip the 220. The point I'm trying to make is that 400 isn't enough. The good news is that once you're at 400 it just takes about a minute on the next three grits to get you where you need to be. You should be able to pick up an assortment with most of these at any auto parts store for about three bucks. Look up scary sharp for more info on this.
So far as spending money on a buffing wheel, leather strop, diamond stone... etc. I'd spend the six bucks on this, see how far you get and decide from there. Stones might speed things up, and a strop might get things a little sharper, but this is money that's probably better spend elsewhere in your shop. At least for now....
I'd pretty much echo BepperB's comments. 400 isn't enough. If you can still see any scratches at all on the back or bevel, it isn't sharp enough. Lee Valley has some really fine stuff that works great with the scary sharp method for the final honing and polishing
http://www.leevalley.com/wood/page.aspx?c=2&p=33004&cat=1,43072
I'd also agree with him about skipping the lower grits most of the time. IMO you can probably skip the 400 grit most times too. If you just need to re-hone and polish you can probably start at 600 or 800, then 1200, then the micro fine LV type stuff.
Where the scary sharp method loses it's appeal is in the initial sharpening that you've just gone through. The good news is, it's not often you need to repeat the whole process. Scary sharp IS incredibly tedious for doing the back flattening and removing any nicks. Coarser sandpaper (60/80/100/150), water/oilstones, or diamond plates can speed it up but it's still all handmotion, so there's only so fast it will ever be. Sanding screen that's used by drywallers is about the fastest thing I've found so far short of a grinder.If you build it - he will come.
Everyone has different ideas, but for me, if it's sharp enough to shave with, it's sharp enough to work wood with.
YMMV.
I was just watching a video of Tage Frid cutting dovetails. He showed how he sharpened his chisels using 220 grit sandpaper on his belt sander. I have to wonder if so much of our sharpening is really overkill. If a great master like Frid does it in such a simple fashion....
Dick Durbin
With all due respect to those who can get a great edge by hand sharpening,I have the same quetion. Is it really necesary to go to 5000 grit? How can Tage get an edge with 250 grit?
I dont claim to know the answer, but I have always wondered. If you go to 5000 grit, doesnt one or two cuts with the chisel dull the edge back to something akin to the higher grit edge.I have gotten very sharp edges on knives by grinding with 220 till I get a burr. I then buff with a medium grit and the blade easily shaves hair. Takes only a few minutes max. I would like to replicate this by hand but hate to waste a lot of time if not necessary. Can someone please explain.
Thanks,
Zuge
zuge,
If you look at the cutting edge under a microscope, the 250 grit will produce a toothed edge. When you go to higher grit, say 8000, the cutting edge will have a much more even or smooth cutting edge.
When you cut wood with the toothed edge, you distribute high pressure over a small area (the point of each tooth) and the wear is accelerated compared to the smooth edge, where pressure is distributed over the entire edge.
In conclusion, the finer grit will give you longer usage, before needing the next sharpening.
You talk about a buffer, which will give you the same finish as a very fine stone, eg. 8000, or even better. It will be much quicker on the buffer, but the disadvantage is that you lose the exact shape of the cutting edge.
By the way, I have tried one of those paper wheels in the link below and the results are superb.
http://www.grizzly.com/products/item.cfm?itemnumber=G5939&
Thanks for the response. To clarify, if I use the 220 belt and then buff, do I overcome the ragged edge disadvantage of only going to 220?
Thanks,
Zuge and get the
You probably want to go a bit finer, at least 400 with paper, or 750 on a diamond stone, or 1000 on a water stone. (There are different standards for grit, these will give you the same finish approximately) Then you should be able to stay on the buffing wheel for a long time, before you have to reshape the bevel.
Zuge,
For my money, your correct. It really doesn't make sense to sharpen/hone a hand chisel to 5000 grit and then pound away with a mallet. What all blades, knives and chisels do is roll their edge under use...honing removes the rolled edge. Trying to cut/chop with a rolled edge worse than trying to cut/chop with a less sharp tool with no rolled edge. The point being, you need to strike a balance between sharpness and intended use. A plane blade is handled more gently (or should be) and feather cuts are desirable...therefor sharper is better but even then it depends if your in the finishing phase or leveling stock. So to a paring chisel, generally sharper is better.
BG. Not all edges roll under use. Some edges fracture in use as they are not soft enough to roll [some Japanese chisels etc.] When you hone on a fine stone you are polishing the edge same as going from your first grit of sandpaper to your second. Its all just an issue of level of polish. How sharp is sharp enough. Better steel holds it's edge longer. I have personally been told by Chris Becksvoort that he sharpens his Barr Quarton chisels about every 3 months. So if honing removes a rolled edge, the previous grit must have created the rolled edge or the use of the chisel created the rolled edge.
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