Cast-Iron or Glass for Stone Flatten from WoodCentral

This discussion began with a post from a woodworker who was looking for an effective – yet inexpensive – way to flatten his oilstones, without purchasing a diamond stone. He began by sharing his first attempt – which hadn't worked out so well. - Editor

"I tried and failed to flatten my oilstones by rubbing them on the side of a large grinding wheel, and I'm reluctant to shell out the dough for a diamond stone. At this point, I'm considering rubbing the stones on a cast-iron or glass plate charged with a water-based grinding paste. I guess my first question is: does this stand a chance of working at all? (I don't pretend to know what I'm talking about.) Remember, all I'm looking to do (at this point) is true up oilstones using a coarse grinding paste." - Nathan

At first, it seemed a bit as if Nathan was talking to himself, since the next two posts in the discussion came from him as well, citing information he had found when searching the archives of the messageboard. - Editor

"Using the new search function here on WoodCentral, I came up with this 2003 message from Russel Seaton. The gist of it is that the grinding particles will roll around on the glass plate and abrade it, whereas on cast-iron they become embedded and stay in one place....In a message Bill Tindall posted in 2008; I quote: 'The cast iron works best with the small grits. Acrylic (Plexiglas) works best for coarse grits as they embed better.' So I'm off to get a piece of acrylic."- Nathan

At this point, the Bill Tindall cited in Nathan's response to himself jumped into the discussion for some clarification. - Editor

"The acrylic worked well when abrading a piece of steel. I am not certain that this will be a good choice for flattening a stone. Do let us know how it works out. The principle is clear, though. You want the softer material to be what the diamond goes on so it stays fixed in place and the harder material, that which is moved across the abrasive, to be abraded. If the stone is porous, you will trap a lot of diamond particles in the stone. This result could be beneficial or not. Definitely not if a coarse diamond particle gets trapped in a fine particle stone. If the stone has a soft bond, then these trapped diamonds will quickly wash away with the grinding gunge, but on a hard oil stone [they] are there forever." - Bill Tindall

Other woodworkers then began participating in the discussion, with their own suggestions. - Editor

"About every two or three years, I flatten my stones en masse. I go to a local plate glass store and have them cut me a section that fits into a rectangular baking pan. I have a supply of #60 grit abrasive that will last forever. Using water and the abrasive I make a slurry, and then it's grinding using a figure 8 pattern until the stones are flat. I've got 8 or 10 stones, but it doesn't take very long. I think the guy charged me $5 last time for the glass. Even the hard Arkansas don't take long."- Ron Bauman

"Using diamonds to flatten oilstones is far and away the fastest, most efficient way of doing it. DMT makes a flat strop, using monocrystalline diamonds bonded to a nickel backing and fixed to a steel plate. They also make diamond paste for really fine honing. Don't make things woodworking harder then they need to be." - Fred D.

The original poster then had a follow-up question to this idea. - Editor

"I'm cheap by nature, so I'd rather spend days or weeks searching than just buy a ready-made product. But in the end, I will probably break down and get the DMT strop. Do you recommend coarse or extra coarse for flattening oilstones? I read somewhere that coarser grits might score the finer oilstones, which might cause a temporary performance loss." - Nathan

And got this response.

"Sometimes I get the feeling that flattening oilstones is being overthought. If you buy a good grade of Arrkansas or or man-made like Norton and pay attention to the way you use it, resurfacing it should not be a constant thing you need to do. I have, among other stones, a three-stone combination in a rotating case by Norton, and I have never used the medium and coarse grit stones. I go directly from the grinder to the fine stone and, using figure eight lapping patterns, I have yet to need to flatten it, and I do sharpening and honing often.

"In a shop teaching environment where many use the oilstone, I certainly can see the need for more frequent surfacing of the stones. My habit is touching up the plane irons and chisels before any extensive use, and I hollow grind those edges, which makes keeping them sharp longer between grindings easier and faster to hone the edge. This is a subject of much debate, so you may want to experiment between hollow grind and factory ground bezels." - Fred D.

Wood from Crooked Tree from WoodCentral

This discussion began with a woodworker eyeing a tree in his woods, thinking about turning it into lumber. The challenge he faces is that the tree has a significant curve, and he's wondering how that will impact both the lumber and the cutting. - Editor

"I have my eye on a cherry tree that is growing in the edge of the woods. It's tall for a cherry, probably over 40 feet and maybe 20 to 24" at the stump. It is leaning out of the woods and lying on another tree. It's probably leaning three or four feet and has a curve in the log. My question is, what affect the curve would have on the lumber if I have the tree cut and sawed? Would there be internal stress/reaction wood whatever?" - Barry

The first responses focused on the likelihood of reaction wood, which responders agreed was high. - Editor

"There will be a lot of reaction wood. So you'll just have to be careful in sawing it and drying it. You can't take the curve out, but you may be able to use it."- J.L.

"Per Wikipedia and others, the reaction wood will form above the pith in a hardwood, as the tree tries to pull itself upright again. So wood below the pith might be more OK than wood above. If the price is right, of course it's worth trying; at the worst case, you'll get some wood and plenty of high-grade firewood." - Bill H.

"Do you know how long the tree has been leaning? If it had been standing straight for most of its life, that wood should be normal. As for leaning against another tree, this may take the strain out of the equation. As for seeing the reaction wood in cherry, it isn't hard to see and avoid including in your work. When you cut the tree, finding the pith off-center might be an indication of grown stress, while centered would probably give more likely good results."- Keith

A respondent then chimed in with concern about the process of actually cutting a leaning tree. - Editor

"If you don't know how to cut a leaning tree, find someone that does. They are easy to split, and that will ruin a lot of wood, and ruin your day if they split inconveniently. I don't deny the concept of reaction wood and the like, but I suspect that it is less an issue than some make of it. Of the thousands of board feet of lumber I have planed and a lesser amount worked, I have never encountered a piece of wood that was not usable except for obvious defects like knots, rot, etc." - Bill T.

The original poster then asked for more advice on the cutting – and presented a further complication. - Editor

"I have been thinking about cutting it. It's on the family farm so I can get it free. But free stuff is rarely free and sometimes not even cheap. One of the the things holding me back on this one is it is overtaken with poison ivy. Major vines growing on the tree. I'm scratching thinking about it.

How would you saw it? I know a guy nearby with a band mill." - Barry

Not surprisingly, the discussion then veered off in the direction of poison ivy. - Editor

"I've been told that poison ivy is a real pretty purple color if you care to work it. Same source told me that it will take 4- plus years for the oils that are responsible for the allergic reaction to diminish to the point it can be worked." - R.P.

"Most of the time the active oil stays with the leaves and vines. If you get rid off them (soon), you may be able to cut it with relative safety." - J.L.

"I'll get a rash if I touch poison ivy, but I've cut many hundreds of vines here at the farm, some up to 4" in diameter, and I've never had a problem. Some of the trees looked like poison ivy trees with long horizontal poison ivy branches extending up to the canopy!

"I usually work when there are no leaves. If you cut in the winter , you are naturally covered with more clothing which helps. If I do work without gloves or touch something, I simply wash up within 15 minutes or so. I generally sever the vine near the ground and let it die and rot in the tree - if I get a log for my sawmill that is covered with vines, I'll wear gloves to pull it off and put the vines in the woods somewhere to rot. Be careful about burning poison ivy vines. I've heard stories of people who were so sensitive that the smoke would give them an allergic reaction. I'd hate to send a neighbor to the hospital." John K. J.

Some respondents, however, also had much to say about cutting the tree. - Editor

"As for cutting into lumber, your sawyer will probably take care of that. You obviously wouldn't want to put it on a horizontal mill with the curve up or down. That would make the grain run-out up and down through the face.

"Sawing with the curve flat to the bed, through and through, will allow the curve to the thickness of the plank, unless there is some spiraling grain, which is not unusual in edge or yard trees, in which case, you will be wasting your time on it. Don't ask how I might know these things.

"My suggestion, is to take your framing hammer out to it, Strike it across the grain at about 45º to knock some bark off. You can then see how the grain runs just under the bark. It is not unusual for cherry to start growing a block model figure on the inside of a crook, which can be kinda nice.

"But if it has a lot of spiral grain due to lopsided canopy causing twisting action when the wind blows, the grain may resemble a bia-ply tire, which makes for some really twisted lumber that will be hard to use if you need strength, as in chair legs, etc. where the grain follows the grown curve. Stacking and stickering grown curved lumber is not pretty."- Keith

"The ivy part is easy. Cut it now, and soon the vines will be dead and, when they dry out, relatively harmless. I am exceptionally allergic to poison ivy, but I find it benign after it has been cut and dried out.

"Let me reemphasize the risks of cutting a leaning tree. While it might seem trivial, it's going to reliably fall the direction it is leaning; the risk is that it will fall at an unpredictable time due to the stress caused by its leaning. The result can be that the center of the tree will split out or the whole tree may split. The resulting pieces can travel in unexpected directions at a rate of speed that will exceed your reaction time. There are techniques for dealing with this situation that will be known to a timber cutter. Best to let the person doing the band sawing cut it, presuming he is experienced cutting timber."- Bill T.