Thread: Favourite coarse stones?

Hello,

I'm just mor reader than user. So now I'm only plan to buy coarse stone in a few months, but it will be Shapton for coarse stone.
Very often I read a Russian woodworker forum - Ìàñòåðîâîé - Ãëàâíàÿ ñòðàíèöà
So here is a thread

ßïîíñêèå âîäíûå çàòî÷íûå êàìíè — òåïåðü è â Ðîññèè

I understand that you not speak Russian but the last message of 'Zmey' - person who conduct sharpening master-class among hobbyist woodworkers speaks the following:
I've fully moved to a Shapton abrasives. During the year of use Shapton stone 220 grit passed away only 0,2 millimeters. This means that 1 millimeter will pass in the 5 years. Thickness of abrasive is 5 mm, so I have near 20 years of work life for this stone.

'Zmey' speaks about Shapton stones on the glass or steel plate, as it seems to me.

Regards .
Sergey.

By the way - as regarding for me I've choosed for beginning more modest solution and cheaper - Sigma POwer Select II 1000/6000 combined stone was ordered. Let's try and after will see.

The Shapton #120 is similar to the King you have, soft and very friable. Works well enough, but it won't last long.

The Shapton #220 is too hard to be effective with anything hard unless you raise a slurry first. Even then, I'm not a fan. It just doesn't work.

Shapton GS #120 is again, too hard. It's the right stuff, but too hard and won't cut properly on anything really hard. Normal steel, it'll probably be ok but I've not got the temperament to deal with stones that need excessive attention. It'll be ok for knives, maybe.

Shapton GS #320 isn't bad, but it's thin and won't last long.

Shapton GS #500 is pretty good, but it's also thin and won't last long.

Suehiro Cerax #300 is very fast, good dish resistance, cheap and BIG.

Suehiro Gokumyo-Ryu #300 is dual density. One side is a softer version of the other, hard side. Very fast, works with everything well. The hard side doesn't dish and works very well to clean up after the soft side. Because it covers both bases, it's not compromised but it's seriously expensive.

Sigma #120 is a monster, but it's also very coarse and not ideal for blade backs. Grinding bevels, it's good.

Sigma Select II #240 is rather soft, very fast but it's slightly harder than most in this grit range and much better for it.

Sigma #400 works very well for both bevel and blade backs. Doesn't dish very much, isn't the fastest but can be made to work faster if needed and easily.

Beston #500 isn't bad but it's a very 'dry' feeling stone. It's not bad, but I'm not a fan.

Naniwa Superstone #220 is too slow and soft. Just not good enough, but if you got stuck with one it'll work. Not recommended.

Naniwa Chosera #400 is very smooth, works well enough but is outclassed by half the other stones mentioned.

King #300 is very hard, but with slurry on it (need to create it) it works well and isn't too expensive. Good for blade backs, less so for bevels and rehabbing.

Anything else I have is either not commercially available and good or really substandard and I won't give them a mention.

What's I've written there is a list of what I have and have used, and is written about because it's been mentioned or because they're good.

Sergey, good luck with that stone.

Stu.

Thanks Stu for that comprehensive run down. I also gathered some useful info from your post on Chris Hall's blog. It sounds like the Sigma 120 and 400 would fit my needs and budget.

I found some other discussions of diamond lapping, and the take home point is that loose diamonds will cross-contaminate across grits via embedding in softer steel, which helps explain why fixed diamond plates are typically used in the course grits, while loose diamond (usually in paste form) is more acceptable for finer grits. A good diamond powder for lapping would be the friable type, which eases the transition between grits.

Further to Stu's comprehensive post above....

I only had a King #300, plus various coarser SiC stones for a long time. I have never liked SiC for rehabbing blades, and the King got the job done too slowly.

So I looked for a coarser more aggressive waterstone, and decided on the Sigma Select II #240. Yes, soft, but it gets the job done quickly, you just have to keep it flat. No big deal, and at the current rate of wear it will outlast me, anyway.

If the #240 has too much work to do, I will begin with a diamond plate or if really major amounts of metal removal are required I will start with the diamond or CBN wheel on the bench grinder. These wheels cut cool (therefore safe) and eat metal so quickly that they are not for the faint hearted!

I do use a Bester #700 as an interim stone between the Sig Sel II #240 and #1000, more to get to see if the #240 has done the job before losing any of the #1000 finding that out.

I am hesitant about using diamond grit/paste. You only have to get the odd loose particle in the wrong place and it will undo all of your good work on a fine grit stone, or even worse embed itself in one of your good natural waterstones.... Good diamond plates and wheels rarely shed grit and with waterstones you wash everything clean before moving to the next finer grit.

Stu, thank you for such wide and detailed explanation.

Sergey