Sharpening and/or flattening - diamond stones.

[Robert WA]

I read an article in a mag. a month or so ago about diamond stones.

Apparently there are two types, and one is better than the other. Of course, I lost the article. Is anyone out there in the know?

I have some serious blade flattening to do. A bundle of old chisels came into my hands. Is a diamond stone or, maybe, 2 or 3 diamond stones of different grits, the way to go?

Cheers

Rob

[lyctus]

Rob,
The two types you probably refer to are the solid face type and the perforated type, one manufacturer, Eselap offers the solid coated steels and the other main player is DMT, this company offers both types. DMT say that they offer both types to counteract folk who feel the need for the solid coat type having to purchase another brand, as DMT have only been making the solid coat type for a few years, the perforated type having been their invention, and exclusive offering for many many years.As you can imagine, the woodworking fraternity is only one of many markets the makers of diamond coated steels make their product for. Two of the main attributes of diamond coated sharpeners is that they remain perfectly flat for the life of the sharpener(many many years) and that they require no lubricant to acheive a fast razor edge. They are available in a number of grades, typically superfine-fine-medium-coarse....there are no "grits" as in alox or silica carbide stones.
The purpose of the perforated type steels is to speed up the sharpening process and as a repository for the metal worn of the blade being sharpened.
Diamond sharpeners work beautifully.
Recently a spate of cheap chinese made diamond steels appeared in the market place which offer an economy entry into the world of diamond sharpening, but may not be as flat as the name brand products.
Diamond hones will sharpen HSS, Carbon Steel, tungsten edges which makes them very handy in the woodworkshop.
Buy the best you can afford. Fine or medium grade would be my first choice.

[IanW]

Recently a spate of cheap chinese made diamond steels appeared in the market place which offer an economy entry into the world of diamond sharpening, but may not be as flat as the name brand products.

Yes, a friend bought one of them last year - cuts well enough, but has a concave surface which doesn't do a lot for the flatness of plane blade and chisel backs.

I've used a diamond plate for years, for initial cleanup off the grinder, and to lap backs. They are the easiest way to keep your backs truly flat. This year I lashed out and bought a big fine/coarse double-sided plate. Now that the pain of parting with all those $$s has all but passed, I'm really pleased with it - gets new blades or old ones being refurbished up to par in no time flat (pun intended!).
However, being the boring, stick-with-what-you-know type, I still use my two Arkansas stones for honing. If I didn't have them, and was starting from scratch (more puns?) I'd almost certainly go with waterstones.
Cheers,

[AlexS]

I bought a set of the el cheapo perforated ones. Not worth a pincha for sharpening, but OK for dressing the wheel of the wet grinder.

[MathewA]

The two types of diamond used are monocrystalline and polycrystalline. The mono is much more wear resistant than poly. And as can be expected the mono is much more expensive. DMT makes a good steel diamond plate, Norton makes a better one. They come in a variety of sizes up to 11" long by 3". The bigger you want the more you'll pay. You can get them with a solid steel bed or a plastic/steel bed. Plastic has flex and may not be perfectly flat; then again the steel bed may not be flat if you buy a cheap diamond stone. I have a 600x which does a good enough job lapping the tools I make. I should get a 1200x to finish up with. Depending on how un-flat your chisels are you might want to look into a coarser stone

[Robert WA]

Thanks everyone.
Next question is, where to buy.
I have recently bought some stuff from Lee Valley in Canada and got a good price, even allowing for freight. I checked there for diamond stones and found one that was more expensive than the Oz equivalent.
Any ideas???