Sharpenining woes . . .

[spwiz5578]

So, I finally got my hands on some nice Shapton Glass stones, the 1K and 4K. Up to this point, my irons and chisels had seen nothing better than 600 grit wet/dry sandpaper. Eventually I'll get the 8K stone, but that's not the point of this post.

The stones looked great right out of the box. I drew a grid in pencil on them and flattened them over a sheet of 400 grit wet/dry on a granite surfacing plate. They weren't perfect, but not far off. Once I was satisfied with their flatness, I starting in on using them. I took out my Stanley 92 shoulder plane and disassembled it. The iron is only 3/4" wide and barely that long at the tip, so I figured it would be a good iron to start on given the fairly minimal surface area. I started on the 1K stone. The swarf began to build. Not long thereafter, the metal "filings" began to streak under the iron as I moved back and forth. I periodically sprayed more water on the stone and wiped off the blade. The streaking continued. I could see progress being made, but, instead of a fine scratch pattern, I saw an even haze on the worked area.

So here's my question(s). Am I pressing down too hard, or not hard enough? The shaptons are very dense, so I don't think they' be clogging. Does anyone have any experience like this? Admittedly, I am fairly new to had sharpening, but I didn't expect these results. FYI, the cloudy surface didn't discourage me any. I continues onto the 4K stone and got a similarly hazy, yet a bit shinier surface. The results of the sharpening session left a little less hair on my arm, and some cross grain cherry shavings on the floor, but I can't help think a mirror polished finish would produce even better results.

Surely there are some sharpening gurus out there that can help me out.

Thanks for looking, and thanks in advance for any help you may provide.

Sean

[wilburpan]

Despite popular belief, mirror finish is not a requirement for a tool being sharp. Having two flat surfaces intersecting is. You can have a flat surface with a mirror finish, a hazy finish like you are seeing, or even a matte finish. Japanese woodworkers actually prize a hazy finish more than a mirror finish for their tools.

It sounds like you have a sharp tool, and any limitation on your edge isn't due to the hazy finish, but due to stopping at 4000 grit. Not that stopping there is necessarily bad if you are satisfied with the results, but you'll get better results going up to an 8000 grit waterstone, or a strop.

If you have lots of time to waste, I have an uber-geeky explanation of this on a post on my blog.

[mlingenfelter]

I agree, you really need to go to 8000 or better before you will see a real "mirror" finish. Also, the type of metal you have may also make a difference. I find A2 steel doesn't produce a "mirror like" finish, as other high-carbon steels do. I have the Shaptons and I go up to 8000 with my sharpening. You get a very polished finish with A2, but it's not what I would call "mirror like" at least at 8000. If you hold it up to the some print, you can see a clear reflection. Some people claim you can extend your working time by going above 8000, but the stones start to get really expensive above 8000. I get very good results stopping at 8000.

Mike

[jlloydparks]

I agree with Wilbur here. Mirror does not mean sharp. I can polish a piece of steel that looks like a roller coaster and couldn't cut warm butter up to a mirror easily enough. Nowhere, is this more evident than if you use oilstones. The finish that comes off an oilstone is matte in my opinion. However, I can shave with the finish and it cuts hard maple as if it is warm butter.

I agree stopping at 4000 will produce a good edge, but not a great edge. Going the extra distance and using an 8,000 grit stone will show benefits in both sharpness and edge durability. You could also use a leather or mdf strop with the green polishing compound as well.

You can see what the master Ron Hock says about Matte finishes over at his blog - Matte Surface Mystery.

[Onboard]

I saw a video on hand tools by Frank Klausz. He did his initial sharpening, to set the angle, on a low speed grinder. He then went to a 1000 grit water stone and then moved to a 6,000 grit stone. That is as high as he went. I don't remember if he used a strop after that or not.

[Torch02]

The key is not to look for a shine on each grit of paper/stone, but rather to see consistent scratch marks across the whole area you are sharpening. When the blade is dull and you go to the 600 grit paper (or whatever your coarse level is), you want to see 600-grit scratches consistently on the surface. Once you've gotten there, you move to the next grit. As you start working on the 1000-grit stone, you want to see the 100-grit scratches replace the 600-grit scratches - consistently across the surface.

Wash, rinse, repeat - per grit.

[spwiz5578]

Thanks for all the replies. I'm aware that mirror doesn't equal sharp. I was put off a bit when looking for the 1000 grit scratch pattern to see not so much scratches, but a dull looking surface. I still worked until a consistent burr formed and moved up to 4000. Trust me, the 8000 is on my shopping list, but I don't know when I'll pull the trigger. Lots of other things to get for the shop and projects, it's hard to know where to start.

Again, thank you for all your input.

Sean