Sharpening advice please - Cosman vs 3M papers

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TJC

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Hi there, new to these forums and hoping for some assistance. Also new to word working generally, just starting out.

I was hoping for advice on sharpening, particularly between the Rob Cosman (and others) stones system or the 3M sharpening papers that are designed to be stuck to a flat block. Any specific pros or cons I should be aware of. Initially will be for chisels and one or 2 planes, I expect the planes will be sharpened flat, nothing special.

Thanks in advance.
 
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Nothing wrong at all with a good old fashioned India oil stone! Cheap, fast, and works very well in conjunction with a leather strop and you won't see much difference between the results compared to the high-end stones as a beginner.

I used to also go "Pfft those are worthless" until a persistent old curmudgeon on here made me think twice and give it a shot.
 
Thanks Trevanion. I think the only major reservation I have over that direction is flatting the stone (or lack thereof). I'm trying to start right with something reasonably silly person proof that I won't throw out and move on from in 6 months, it seems the most fundamental skill going. You think these would be compatible with that?
 
I use a double sided Eeze Lap diamond plate, coarse250 grit, and fine 600 grit, (although they are now finer than that), and a fine slate stone of some sort, and then strop on a piece of leather stuck to a flat piece of ply. Personally, I don't like using wet and dry paper especially with chisels, it's far too easy to rip the paper. In the long run, diamond plates will work out cheaper than paper.

Nigel.
 
Sharpening used to be a topic guaranteed to start a good forum fight, but that problem has.....erm..........gone away. I've used every possible sharpening medium other than waterstones, , and have settled for diamond plates. The lapping paper/ abrasive thing is a faff, because they tear and get wrinkled and wear out, and you spend more time playing with them rather than the tool you're trying to hone. It gets really pricey, too. Get yourself an oil stone or some diamond plates, learn to raise a burr on the back of the blade, and learn the importance of stropping. And don't get too scientific about it, or too fussed with angles. Speed and sharpness are all that count.
 
....the only major reservation I have over that direction is flatting the stone.......

If you buy a new one it will be ten years before you have worn a discernible dish in it, and it is still perfectly good even then. Maybe a newcomer should avoid a second hand one for that reason. Diamond plates probably won't last 10 years, but they will remain flat. If you plan to use a honing guide, then you probably want a larger surface area than an oilstone provides.....but you can make it work.
 
Thanks Trevanion. I think the only major reservation I have over that direction is flatting the stone (or lack thereof). I'm trying to start right with something reasonably silly person proof that I won't throw out and move on from in 6 months, it seems the most fundamental skill going. You think these would be compatible with that?

I've touched the flatness of mine up once or twice on the back of a broken large ceramic tile for proper cheapskatery, bearing in mind that's once or twice in a year or so of very frequent use compared to every sharpening session with a water stone. The India stones (good quality ones anyway) are so hard-wearing that it takes quite a long time before they become dished anyway compared to water stones. Another stone I have is a natural Washita stone, these are excellent finishing stones and are extraordinarily hard wearing but are quite expensive to get a hold of unless you know what you're looking at on unclear eBay listings.

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Diamond plates are also pretty good but I prefer the stones myself, a lot of it is down to personal preference rather than any method being massively better than the other, once you go down that path you get into real pedantry.
 
I bought a set of three outstandingly cheap diamond plates, because I already have a vintage oil stone of unknown provenance, which didn't seem to make things sharp. To begin with the diamond plates also didn't seem to really work, but last time I sharpened my plane blade I tried it on my forearm (because everyone does, it would seem), and one pass took all the hair off. Super - sharp!

I can't remember which ones I bought, but they look like these: https://www.amazon.co.uk/Am-Tech-E2...late&qid=1598387242&sr=8-18&tag=duckduckgo-20

Try them, and if it doesn't work out, you have lost £6. Not the end of the world. I should say I also strop with car polishing compound on an offcut of mdf. I am still learning how it all works, and either the diamond plates need a bit of time to bed in, or I needed a bit of time to get the hang of it. Perseverance pays off either way.
 
I'm seeing universal disdain for the papers, which makes sense really. They may be flavour of the month right now...

Would 3 grades be appropriate to start with? Something coarse for initial setting, and then a fine and very fine for day to day?
 
I plumped for Japanese waterstones, and I find them pretty easy now (after a matter of weeks). Flattening them after use (and sometimes they just don't need flattening) takes minutes so it's not really something I'd use as a negative factor.

I was going to try the sharpening papers but it seemed like an expensive option long-term.
 
Would 3 grades be appropriate to start with? Something coarse for initial setting, and then a fine and very fine for day to day?

The India stone technically has two grades on it but I only ever use the finer side and then go straight to the strop with a bit of compound every now and then, the total outlay would be around £30-35 or so.
 
The coarser side would be enough to set up the backs of new chisels, etc?
 
The coarser side would be enough to set up the backs of new chisels, etc?

The fine side would do it easily, even the 'flatness' of the back of chisels is something that's up for contention. I don't believe it's absolutely critical to have a completely flat back but some do and will preach about it.

I make money with my tools, others don't. 🤷‍♂️ 😂
 
I'd be looking for Ultex hones (if their on that frequent half price sale for a tenner each, that is)
If not, I'd be looking for three similar priced or cheaper diamond hones that are bonded to a heavy nickel coated steel plate.
I don't like double sided hones as it will get contaminated with grit unless you have
a holder suspending them in a device.
You can go even cheaper and get the DMD card type, but you might want to bond them to something heavy.
The diamond hones will get your irons flattened, and by the time you've done a few chisels and plane irons, the finest one should be getting more suitable for a keener edge.

A good idea to condition them first is by lapping, as there is no pointy edge to pick up the fresh loose diamonds and pull up a patch of them.
That's not saying that they can't be stripped by the back of a plane iron or chisel, especially if there is a very concave shape,
but if you are aware that sharp sides can shear diamonds off the edges of the hones, it wont happen, and they will last you if you don't gouge the corners of the irons into them.

All in all, the least amount of faff to be concerned with, but the main pros in my view is...
No danger of them dropping, if you don't have a sharpening station.

Will stay flat, so will take many factors out of the equation, so you can be sure that a certain technique will be repeatable, or figuring out something is not down to a hone that's gone out of flatness.

No maintenance, which kind of goes back to the second point,
being able to just zone into the technique, and not being concerned with covering every centimeter of the whole stone, or lip on an edge of a wearable hone,
This can cause headaches trying to concentrate on, and when you come off the stone wrong and take a chip off the edge, its no fun.

Cheaper than the rest too, diamonds pale in comparison to the price of waterstones, especially the ones what Cosman uses.
Pick up the oil stones at a boot sale sometime.

Tom
 
I’ve been using the 3M sheets for years now & wouldn’t go back to oil, water or diamond stones for sharpening chisels & plane blades, I get mine from Scary Sharpening Abrasive Sheets (Trial Pack)

I use Trend diamond lapping fluid as a lubricant Trend Lapping Fluid 100ml mainly because I had a lot left when I gave up on diamond stones but I’ve found it works well on abrasive sheets.

All the systems work & a lot of it is personal choice but particularly for someone new to sharpening the 3m sheets are a great inexpensive introduction presumably if you read the write up in the first link this is why Peter uses them in his teaching.

Best of f luck with whatever you choose.
 
I’ve been using the 3M sheets for years now & wouldn’t go back to oil, water or diamond stones for sharpening chisels & plane blades, I get mine from Scary Sharpening Abrasive Sheets (Trial Pack)

I use Trend diamond lapping fluid as a lubricant Trend Lapping Fluid 100ml mainly because I had a lot left when I gave up on diamond stones but I’ve found it works well on abrasive sheets.

All the systems work & a lot of it is personal choice but particularly for someone new to sharpening the 3m sheets are a great inexpensive introduction presumably if you read the write up in the first link this is why Peter uses them in his teaching.

Best of f luck with whatever you choose.


I reckon you're the only person I've ever heard of, Doug, who has gone from diamond to abrasive paper. The journey is generally very much in the opposite direction. What was it about diamond plates that made you think "I should give lapping paper a try"?
 
I reckon you're the only person I've ever heard of, Doug, who has gone from diamond to abrasive paper. The journey is generally very much in the opposite direction. What was it about diamond plates that made you think "I should give lapping paper a try"?

I have done the same. The scary sharp system is sooo accessible and simple. If you use the same technique as you use on stones, you will not have any success. Check out
The head of workshop heaven runs through the differences and how it can work so well.
 
No need to explain to me how "scary sharp" works. I used it for a year or so, before giving it up as a faff and moving to diamond plates. You describe it as accessible and simple, and I'll counter that with torn paper, cleaning up the glass, wrinkles, expense, and time wasted changing paper. You get none of that with diamond plates. I'm not trying to persuade you, but there are newcomers who might be sucked in by the hype around "scary sharp" who would definitely benefit from starting with diamond plates.
 
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