Diamond Paste

[Metod Alif]

I had a junked piece of cast iron for some 20 years. It looked similar to the extension wings on my table saw but smaller, about 18"x10". Few days ago I cut it up with a hacksaw into 5 pieces, about 3"x10" each. There is some rust and visible dishing, almost 1/16" at the middle. I did not check for the flatness before cutting but suspect that some tension was released because of cutting through the ribs.
Now I have two questions, the first is how to flatten the surfaces (not looking around for a machine shop yet). I would be willing to get a 16" bastard cut file, and plane the surfaces flat. Of course, this is just an idea on the paper. Should I have any hope to succeed?
The second question is, how to best use the plates - what grit(s) diamond paste would be most appropriate. I looked at Derek Cohen's site (Derek, I hope you chime in), which got me to cut the piece instead of tossing it away. Derek has (at the latest count) three plates from old planes with .5, 10 and 40 microns paste, but little about their actual use.
I would be thankful for any suggestions. I am not overly enthusiastic with the flattening issue - but if the payoff is worthy, I would pursue it, even possibly through a machine shop.

Metod

[Stanley Covington]

Metod:

Try some of the information available on this site.

http://www.circuitousroot.com/artifi...ing/index.html

[Chris Fournier]

Why go to the trouble and expense? Get yourself a granite inspection plate and some wet dry paper. Less trouble, less cost and very effective. I simply don't understand the hoops that folks are jumping through in order to "properly" sharpen woodworking tools.

An A grade 12" X18" granite inspection plate will set you back less than the 16" file that you mentioned.

[Jim Matthews]

As a recent convert to diamond plated sharpening stones, I think the appeal of the method is both speed and the final degree of polish that can be achieved.

With wet/dry carbide paper, I can only pull the blade - which works.
Using either a diamond plated stone or diamond paste, the steel is cut in both directions.

Did I mention it was really fast?

[Metod Alif]

Stanley,
Thanks for the site. I just glanced at it -it calls for repeated visits. Aside from making a few metal planes, I have hardly any metalworking experience. I enjoy learning new stuff to complement my hobby woodworking.
Best wishes,
Metod

[Metod Alif]

Chris,
"I simply don't understand the hoops that folks are jumping through in order to "properly" sharpen woodworking tools."
Some folks look for new sharpening media (and will probably keep doing so) because they can't get competent with what they have. I use water stones (all from Japan Woodworker) and strops for my Japanese chisels and O1/A2 plane irons. I do not need new media as I am competent enough (my criteria) with them. I also like to explore other means, if that does not call for substantial outlay. The cast iron piece did not cost me other than the 'effort' to bringing it home. I am willing to spend some money and effort to make it work, for the learning experience itself. I do not expect to achieve better sharpness results than I already do. And if I like the plates better, I won't cry over it.
For honing, I can hold sandpaper with one hand on any flat surface (a block of wood, table saw, jointer bed, piece of granite) and a chisel or iron with the other hand - and get the same sharpness as otherwise. I see 'jumping through the hoops' fine for circus animals and similarly conditioned humans.
Best wishes,

Metod

[Jessica Pierce-LaRose]

Does one need machinists precision flatness for this task? That seems like a lot of work, but I wonder if it's needed. Certainly if waterstones lapped with a diamond plate are flat enough, or sandpaper on a granite tile is flat enough for sharpening plane blades, I don't know if the plates need to be super-precision flat. I could be totally off, of course, but I'd be tempted to use a file or a belt sander or whatever to get close-ish to flat if there's obviously visible problem areas, and then lap the plates on sandpaper on a granite tile or my table saw or whatever.

I have no idea - I could be totally off, but it seems like that would be "flat enough". I also tend to sharpen freehand, so I can probably get away with less flat than maybe like a jig would require.

[Jessica Pierce-LaRose]

Some folks look for new sharpening media (and will probably keep doing so) because they can't get competent with what they have.

I desperately wanted to be one of those people when I was younger, convinced that new system X was going to get me better edges. Fortunately, I was poor, and part of me had better sense. I think it's a terrible way to learn to sharpen; having other variables constantly changing on you. When I was learning to drive, they didn't keep putting behind the wheel of a totally different vehicle every time before I even learned the basics.

I still want some better waterstones, because I'm not thrilled with what I have. But I finally understand what I don't like about the stones I have now, and it's not that I can't get sharp, it's how I get there.

[Derek Cohen]

I had a junked piece of cast iron for some 20 years. It looked similar to the extension wings on my table saw but smaller, about 18"x10". Few days ago I cut it up with a hacksaw into 5 pieces, about 3"x10" each. There is some rust and visible dishing, almost 1/16" at the middle. I did not check for the flatness before cutting but suspect that some tension was released because of cutting through the ribs.
Now I have two questions, the first is how to flatten the surfaces (not looking around for a machine shop yet). I would be willing to get a 16" bastard cut file, and plane the surfaces flat. Of course, this is just an idea on the paper. Should I have any hope to succeed?
The second question is, how to best use the plates - what grit(s) diamond paste would be most appropriate. I looked at Derek Cohen's site (Derek, I hope you chime in), which got me to cut the piece instead of tossing it away. Derek has (at the latest count) three plates from old planes with .5, 10 and 40 microns paste, but little about their actual use.
I would be thankful for any suggestions. I am not overly enthusiastic with the flattening issue - but if the payoff is worthy, I would pursue it, even possibly through a machine shop.

Metod

Hi Metod

Diamond paste is good, but I cannot recommend the path you are travelling to get there. Too much work to flatten the cast iron plates you have. Far simpler and far less effort to convert a few old plane bodies (as I did).

For the reference of others: http://www.inthewoodshop.com/Woodwor...mondpaste.html

Regards from Perth

Derek

[Chris Fournier]

Does one need machinists precision flatness for this task? That seems like a lot of work, but I wonder if it's needed. Certainly if waterstones lapped with a diamond plate are flat enough, or sandpaper on a granite tile is flat enough for sharpening plane blades, I don't know if the plates need to be super-precision flat. I could be totally off, of course, but I'd be tempted to use a file or a belt sander or whatever to get close-ish to flat if there's obviously visible problem areas, and then lap the plates on sandpaper on a granite tile or my table saw or whatever.

I have no idea - I could be totally off, but it seems like that would be "flat enough". I also tend to sharpen freehand, so I can probably get away with less flat than maybe like a jig would require.

Price out a granite inspection plate Joshua, they're dirt cheap and they are incredibly flat with a generous working surface. Once you have one you will find other uses for it I can assure you. I made a stand for mine and use it as my waterstone bench for example. I also have an inscription ready for it when I kick off, there's the $$$ savings!

[Gary Hodgin]

If interested, Enco has a web special on a 12x18x3 granite surface plate accurate within .0002 on web special for $45.95 with free UPS shipping. I paid nearly that amount for my 9X12x2, around $35 as I recall.

http://www.use-enco.com/1/1/1256-bla...-640-0120.html

P.S. The enco plate is a grade B.

[Jim Koepke]

Why go to the trouble and expense? Get yourself a granite inspection plate and some wet dry paper. Less trouble, less cost and very effective. I simply don't understand the hoops that folks are jumping through in order to "properly" sharpen woodworking tools.

It may not be so much "jumping through hoops" as it is the quest for knowledge or the anticipation of traveling unfamiliar territory.

So far, this bug hasn't bitten me too hard. However, after following the link to Derek's chronicle of using broken plane soles to make diamond lapping plates it looks like it may be a project when a few more broken soles find their way into my shop.

For many folks, one sharpening system will be enough. For others, we do not want to leave any stone unturned or unused.

Like me, Metod may prefer first hand experience with such methods and is willing to pay the price to for the privilege.

In my case, oil stones didn't seem to work. After experimenting with scary sharp and then water stones and learning more about the "art of sharpening" my success improved on oil stones.

For some of my needs, oil stones are the best. For other needs, the water stones beat all.

jtk

[David Weaver]

It will be hard to draw file or even belt sand (to remove most of the dip) from a plate that large. The closer it all gets to coplanar, the slower it will go.

Even hand plane bottoms are a pain, as are mild steel laps if they get ouf of flat and don't start flat.

If I were going to go the route of diamonds, I would save the loose diamonds for 1 micron and smaller and use an eze lap or something similar for the 1k grit work. Stretch its life out by maximizing the use of the grinder to minimize the use of the diamonds.

[Kees Heiden]

And how about the backs of vintage chisels and plane blades? I am very fond of old stuff, and I am not a fan of the "ruler trick". Don't know why, it just doesn't feel like a good long term solution.

Vintage irons usually are troublesome. Pitting, convexities, drooping corners that never seem to come coplaner with the rest. I am certainly not looking to flatten the complete iron, but just flattening 3/4" or so is tedious work. At the moment the fastest way for me is the Sigma 120 brick, then a 400, a 1000 etc waterstone. I tried DMT diamond plates, great when new, not so great to downright slow when used for a while. I tried sandpaper on glas. No idea what I am doing wrong, but my sandpapered irons never conform to the flatness of my waterstones, meaning much work on a coarse waterstone again.

So, any new ideas? Something rediculous fast, with a long life, and preferably not too expensive, and not too laborious in itself?

[David Weaver]

a mild steel kanaban, an iron holder device (to allow you to put unlimited pressure on the iron) and loose diamonds of the 80-120 grit range. Make the device out of anything free you have around. A 2x4 and scrap bolts works fine. The virtue being that the kanaban always seems the same, it would be almost sinfully wasteful if you even used a carat of diamonds on a single very pitted iron (Which is about $1 of diamonds), and there is no steel hard enough that it can't be abraded.

You will be able to revive several dozen old pitted irons before flatness becomes an issue, and you will have toned triceps when you're done. WD 40 or something like that for a lubricant (something thin).

Aluminum oxide paper fresh on a long roll might be a little faster when fresh, but it seems to me that the diamonds are about as fast as any once you have a setup, and you have no limitation whatsoever on the amount of pressure you use.

The ruler trick isn't intended to bypass pitting, it's intended to be used on an iron that is flat and fresh, but perhaps just not polished. It's intended to remove the wear from use only, and works extremely well if it's used appropriately, especially in a situation where you have a very hard iron that planes a lot of feet before it's sharpened, and is a bear to polish on the back.

If it is chasing more than wear, though, it can get out of control.