Flattening water stones (Not!)

[gazzer]

I have used waterstones for sharpening for years. Up until a year or so ago, when I bought a Norton flattening stone, I used sandpaper on a glass plate for flattening every few sessions. Lately I have been seeing flaky results. I use a Veritas bevel guide, establish the main bevel with the 800 grit and then hone a microbevel with the 4000. The microbevel was not even or square across the main bevel, so I would compensate by putting a bit more pressure on one side of the chisel or iron. This works just fine, but a bit of a pain.

Anyhow, last night on a whim, I put a rule on the stones I had just flattened the day before. They were concave with about a millimeter dish in the middle! Not believing it, I grabbed a better straight edge and confirmed. A check of the Norton flattening stone told the tale - it was indeed convex, no doubt because of the use it had seen over the last year. It makes sense that it would abrade too, and the pattern makes sense, but it seems like it should not have happened this quick.

I have decided to abandon the Norton stone and go back to sand paper on a flat plate. The other option is to flatten the Norton stone, which actually seems redundant.

In any case, another reminder to always check your references

-G

 

[Mike Davis]

I use a large DMT diamond plate. Never had a problem with it being flat.

 

[boxxmaker]

I always use the sandpaper on about a 1/4" piece of glass to square up my chisles with some cuttin oil,then fine tune em on the diamond stone.Sandpapers cheap and the glass will never bend or warp.

 

[zac]

I've had the same problem. The fact is that the flattening stone needs to be flattened on occasion. I flattend it on a piece of marble with sandpaper and water and then its good for a while longer. It depends on how much sharpenning you're doing as to how often it needs to be done. I decided early on that I was going to stick with water stones and master them.

Good Luck

Zac

 

[Travis Porter]

Wow! I wonder if you have actually worn the flattening stone or if it was defective or just became dished?

I have used a DMT diamond for my flattening as well, but nothing says it is accurate either. Something to be sure to check.

 

[Mike Davis]

The DMT machinist plates are flat and accurate.

I wouldn't trust the plastic ones.

 

[DavidF]

I have had DMT bench stones for over 20 years and they are as flat today as the day I bought them. I tried going the Norton water stone route with a combo 1000/4000 and it dished after very few sharpenings. I could easily flatten it with the "black" DMT, but it was another messy job that seemed unnecessary. I stopped using the stone after a kept putting a radius on my chisels with the dished water stone and I stopped using it. I use the "red" fine dmt followed by 2000 g wet/dry paper on granite or glass. I recently bought the "worksharp" and am actually struggling to get as good a result from it as I had hoped. Still out on the final judgement. I don't like the sharpening port at all! but I'll save that for a review in another thread!

 

[Mike Davis]

The Steel plates are the ones I use for plane blades and flattening.

Like this
http://www.amazon.com/DMT-D8F-Dia-S...ref=sr_1_9?ie=UTF8&s=hi&qid=1258387962&sr=1-9

I keep the small plastic one in my pocket for sharpening my pocket knife but it flexes too much for serious work. All the colored ones (blue, red, green so on) are plastic core with a thin metal plate attached. I don't really trust them to stay absolutely flat.



Sorry David, I read again and you said the plastic ones are still flat after 20 years?

 

[DavidF]

The Steel plates are the ones I use for plane blades and flattening.

Like this
http://www.amazon.com/DMT-D8F-Dia-S...ref=sr_1_9?ie=UTF8&s=hi&qid=1258387962&sr=1-9

I keep the small plastic one in my pocket for sharpening my pocket knife but it flexes too much for serious work. All the colored ones (blue, red, green so on) are plastic core with a thin metal plate attached. I don't really trust them to stay absolutely flat.



Sorry David, I read again and you said the plastic ones are still flat after 20 years?

Yep, spot on..

 

[rahimlee54]

The Steel plates are the ones I use for plane blades and flattening.

Like this
http://www.amazon.com/DMT-D8F-Dia-S...ref=sr_1_9?ie=UTF8&s=hi&qid=1258387962&sr=1-9

I keep the small plastic one in my pocket for sharpening my pocket knife but it flexes too much for serious work. All the colored ones (blue, red, green so on) are plastic core with a thin metal plate attached. I don't really trust them to stay absolutely flat.



Sorry David, I read again and you said the plastic ones are still flat after 20 years?

I'd have to second the DMT plates although I go with the XXC, I use it for knives and a pro sharpener that runs a site said he wouldn't use anything else.

Link

I am not sure how the regular version stacks up but I am sure it does well.

 

[gazzer]

Wow! I wonder if you have actually worn the flattening stone or if it was defective or just became dished?

The stone was flat when bought. I usually laid it on a flat surface and then rubbed the water stone back and forth over it. I guess I was not too attentive about pressure when overlapping the edge of the flattening stone and wore down the ends (and probably did the water stone no favors). A better way may have been to hold the 2 stones in either hand and rub them together in a circular pattern without much overlap.

Waterstones work well for me. It is a hassle to soak; however I find myself only using the coarser grits occasionally. Barring any nicks, it is easy to just polish up the secondary bevel with the 4000x stone (which doesn't require soaking.) I've used the scary sharp method in the past, which I find equally good when I don't cut or crimp the sand paper. The darn trouble is that sharpening stones/tools/supplies aren't cheap and you can go broke in a quest for a better method. I reckon I'll wait until the waterstones wear out until I try something different.

-G