I owe a debt of gratitude to Craig Vandall Stevens for his consultation on the Hock Tools Carving Knives. Linda interviewed Craig about carving knives over a few e-mails to include in Sharp & to The Point, the Hock Tools’ Newsletter. She couldn’t fit the interview into the newsletter, so I’m publishing it here. Thank you Craig for all your help with the knives!
Craig Stevens at College of the Redwoods Marquetry Class, July 2011
Linda: What do you like in a carving tool?
Craig: The shape of the blade, high carbon steel, comfortable cutting angle, a comfortable fit in the hand.
I love the Hock Tools’ Chip Carving Knife. The shape is a winner. It has great balance of handle and blade and it feels like an extension of my own hand. I know there are good knives out there and I have bought them, but I was always on the search. I truly think there is no improvement that Ron could make with this Chip Carver and I don’t know when I have been able to say that.
I’ve pushed carving so hard for myself over the years. I handle these things every day; they need to become part of you. This knife gives me that confidence; it is like my own finger. Ron got it right.
Linda:Which tool do you find yourself using the most, and why?
Linda:Which sharpening method do you favor for quick, in-between sharpenings and which method do you use the most.
Craig: I don’t use a strop on carving knives, as I feel it rounds the bevel shape and steepens the cutting angle. I’ve found that having a straighter bevel makes it easier to accurately maneuver the blade through the wood. I use ceramic water stones for sharpening as well as touching up the edge. These are the same stones (Shapton brand ceramic waterstones) I use for sharpening my plane and chisel blades. Small ceramic hand-held stones are also helpful or touching up the blade. When the blade needs touching up, I use a polishing stone (rather than a strop) to re-attain a sharp edge. After touching up the blade a number of times, I return to the coarse stones to re-establish the geometry of the blade angle.
Linda:How many carving knives do you have? How many do you use?
Craig: I have two knives for chip carving (the chip carver and the stab knife). For general carving at the work bench, I use several Hock knives as well as many knives I’ve made myself using a small gas forge.
Using the Stab Knife (#CKS125)
Linda:What is your favorite thing about Hock Tools carving knives?
Craig: The high quality of the steel used in the knife blades is very important to me. I want the blade to have the ability to be taken to a very fine edge, and I need that edge to hold up well in use. Also, the angle of the blade (in relation to the handle) is very important in chip carving. The Hock Chip Carver not only has the high quality steel that I need, but it also feels very elegant and comfortable in the hand. In use, the knife feels like an extension of my hand, allowing me to draw the blade through the wood accurately and very intuitively.
Linda:Do you make your own handles?
Craig: For the two chip carving knives, I use the Hock handles. For nearly all my other knives, I make my own handles.
Linda:Which woodworkers do you appreciate/admire?
Craig: I appreciate the work of Wharton Esherick, Hans Wegner, Finn Juhl, my teacher Jim Krenov. I also admire the quiet work of many Japanese woodworkers. It’s difficult to say – I guess my appreciation for woodworkers changes and evolves with time. Some I admire for their beautiful sense of proportion, others for the simple, clean lines in their work and others for their command at creating challenging pieces that don’t shout about the complexity. There’s been a lot of beautiful, memorable work that’s been created, both in the past as well as a lot of current work.
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Feel free to e-mail subscribe to Sharp & to The Point or check us out on Facebook for the interview. One question-and-answer Linda did not include in the newsletter was the question about which woodworker would Craig most like to have a conversation with today. Here is that snippet from the cutting room floor: And, just to show the breadth of Craig’s knowledge and how deep his view of furniture design — not to mention how eclectic his aesthetic is — when asked which woodworker in history he would most like to converse with today? Craig Vandall Stevens’ answer came quickly to his lips, Louis Majorelle.
A mahogany bed, known as the Nénuphar bed for its water lily motifs, designed and manufactured by Louis Majorelle around 1902-3, on display at the Musée d'Orsay, Paris.
Louis Majorelle! I have to admit, considering the Japanese and Krenovian influences that persist in Craig’s portfolio, Majorelle, the renown late 19th and early 20th Century French Art Nouveau furniture designer, was a surprise and further illustrates what an elegant and expanded thinker Craig Vandall Stevens truly is.
Hock Carving KnivesAlso available without handles for the DIYer
Last time we looked at the various methods and products that can be used to prevent rust on our tools. This time we’ll look at how to remove it when it’s already there.
I’m using an aquarium for visibility while de-rusting a #5 plane body. I have it only partially in the water/baking soda bath to best illustrate what’s going on. Notice the negative (black) lead from the battery charger is connected to the plane body (the cathode) and the positive (red) lead connects to a piece of stainless steel (the anode) roughly bent to the shape of the tank to provide maximal exposure of the cathode to the anode.
Rust removal
Once rust has occurred, the evil forces of oxidation have stolen some of your iron and you can never have it back — the iron atoms that have been oxidized are no longer available to you — you cannot undo the rust and put the iron atoms back into the tool’s surface from whence they came. So there will be a pit, at the very least, in the surface. If that pit is at or near a cutting edge, you’ll need to abrade the surrounding surface down to the level of the bottom of the pit and just a molecule beyond because you want to be sure to remove all of the rust or it may continue to eat your steel. Anytime you expose fresh metal, it too will need to be protected from further rusting.
Some oxidation is really not material. The blue-gray patina that develops on carbon-steel kitchen knives does little damage, and is just a fact of having and using fine knives (I think carbon-steel knives are vastly superior to so-called “stainless-steel” ones). Sometimes they get a little too motley for my taste and I’ll gently and carefully scrub them back to uniform gray with steel wool. But aggressive red rust is nasty and must be dealt with before too much damage is done. Light sanding and oiling will suffice for some tools — a hammer head or wrench — but cutting edges should be cared for preventatively by one or more of the methods described above.
It is possible to remove rust by chemical or electrolytic action. Citric acid is acclaimed for its ability to dissolve rust much faster than it dissolves the underlying steel and is often used to de-rust tools. Recipes or mixture recommendations vary from one to two ounces of citric acid crystals to 32 ounces of water. Disassemble the tool and immerse the rusty steel parts only. Check on the progress and brush off the loosened rust every few minutes. Treatment with fresh solution can take as little as twenty minutes depending on solution concentration, temperature and agitation. You should experiment to find the technique that works best for you. The acid will eventually attack the steel so don’t leave it in longer than necessary to dissolve the rust. Be sure to rinse the treated parts thoroughly and immediately apply new rust protection.
The electrolytic method is quite simple and if done properly will not harm the iron substrate at all. Here’s what works for me: start with a 5-gallon (20 liter) plastic bucket or similar container almost filled with water into which you’ve added a handful (1.2 metric handfuls) of baking soda to make the electrolyte. For the anode, I prefer something stainless steel — a vegetable steamer or cheese grater. Some stainless steel wires in the bottom of the container will suffice. Stainless lasts longer as an anode — you can use any iron or steel as an anode but it will be consumed by the process. Disassemble as much as you can (some “impossible” screws may loosen in the process) and remove anything that isn’t steel. Suspend the rusty thing, the workpiece, in the solution being very careful that it does not touch the anode at all. The action is “line-of-sight” between the rusty thing and the anode, so you may need to reposition the workpiece or wrap the anode in order to surround it for complete coverage.
The rust has been converted to a chalky black surface coating that should now be wire brushed or sanded off. The clean and rust-free surface will begin to oxidize immediately; don’t delay in applying rust prevention measures.
Connect a battery charger’s positive lead to the anode and the negative lead to the rusty workpiece. Let me say this again: Positive to Anode, Negative to Workpiece. Don’t mix them up because the anode is sacrificed in this reaction and you only want to dissolve the rust, not your rusty thing. You’ll see bubbles rising in the solution as soon as the battery charger is switched on. Through the magic of chemistry the iron oxide that you want to remove is converted back into metallic iron and falls to the bottom of the bucket. It will not re-deposit itself where it came from. The rust will be removed; however, the pitted surface will still be pitted. De-rusting can take a few minutes or a few days depending on the amount of
rust, the amperage available from the charger, etc. Be patient and check the piece occasionally. Bubbles will continue to rise from the piece even after all the rust is gone but don’t worry; at that point you’re just splitting the water into its component oxygen and hydrogen. The resulting de-rusted surface will have a black layer on it that you’ll probably want to wash/wipe off. Dry it thoroughly in an oven, with compressed air or a hair dryer. Rust prevention measures should be applied immediately upon drying the piece or it will rust again in minutes.
That’s it for this excerpt. I hope you’ve learned something about the enemy and how to vanquish it from your shop.
This special “see-through” paint pot allows you to see the canning jar inside that has a blade in it. By evacuating the paint pot, you remove the air from the canning jar as well and the lid seals via atmospheric pressure when the vacuum is removed from the pot. No air in the jar means no water to start rust.
Rust Prevention
What are we to do? Well, there are two basic approaches to rust prevention: prevent water and oxygen from coming in contact with the iron or convert the iron into another compound that is better able to resist oxygen’s efforts.
Desiccation
The simplest way to keep rust from eating your tools is to keep them in a place that is too dry to allow the rust reaction to get started. Woodworkers living in dry climates expend far less time and effort defeating rust than those of us in a moisture enhanced environment. You can keep your tools in a vacuum or a sealed container purged with nitrogen or containing a desiccant of some kind to absorb all the moisture. Okay, not too practical, but here at Hock Tools, less than two miles from the Pacific Ocean, we often store small parts in canning jars that we’ve pulled a vacuum on. Parts are placed into a canning jar with the lid screwed on securely but not too tight. The jar is then placed into a paint pot that’s attached to an old refrigerator compressor via the intake tube and the air is pumped out of the paint pot. The canning jar lids allow the air inside to escape but seal tightly when atmosphere is restored to the paint pot and the small blades or screws are stored in a near-total vacuum that, in one test, has held for over eight years. Not bad. Some people use a low wattage heater or a small light bulb or moisture-absorbing products in their tool box to keep it warm and/or dry.
This piece of steel was half polished and half sand-blasted then placed in and removed from the freezer several times. The moisture that condenses during the exposure of cold metal to warm air is a sure way to create rust. The sand-blasted side provided the texture that corrosion needs to get started.
A common rust-promoting condition that we often see is the condensation that forms when metal parts are moved from a cold place to a warm one. Warm air often holds more moisture than cold air. That moisture can condense on the surface of the cold steel forming myriad beads of “sweat” as you see on you glass of iced tea in the warm air of summer. Each of those beads is a new electrolytic cell corroding the steel beneath. Condensation can even occur when the atmosphere warms up faster than the steel parts. A chilly spring morning can warm up quickly enough to cause metal in the shop to sweat. Circulating the air can help avoid condensation but a moisture resistant coating may be necessary.
Similar to simply keeping tools away from moisture, keeping them polished can help prevent rust by eliminating surface imperfections that can trap a droplet of water, which allows rust to get started. Polished steel is not rust-proof — it still needs rust avoidance and protection measures — but shiny, polished steel tends to stay that way longer than the rough stuff.
These are just a few of the readily available products for preventing and converting rust. There are dozens more: waxes, greases, oils, phosphating compounds and vapor-phase inhibitors.
Occlusion
Other methods used to prevent rust include the various things we do all the time to keep oxygen from attacking anything we care about. We apply barrier films including plating steel with other, less reactive metals such as brass, zinc or chromium or the barrier can be the paint film which protects our cars from damaging oxidization. These measures work well but as we know from experience, the slightest breach in the integrity of the film will allow rust to get started and once it starts it spreads quickly under the chrome or the paint until the coating flakes off and you have nothing left but rust.
With edged tools, we can’t tolerate a film on the cutting edge, yet that’s the part we most care about protecting: a bit of a conundrum.
A film that’s blocking the air and moisture from the steel, however, can be made from things other than paint or plating. Wax, grease, oil, etc. can all become part of the armory we enlist in the defense of our tools. The market has many products to offer and most work well, keeping in mind that some are better suited than others to one application or another.
Generally and with little effort, an edged tool can be oiled after and wiped off before each use. A protective wax coating on a machine table can also perform the double duty of keeping out moisture and allowing things to slide easily over it. The downside for these specific applications is that wax and oil require frequent maintenance and recoating. In neither of these situations would we want a coating of heavy grease, even though grease may be indicated for certain longterm storage needs. The market also offers certain oil-type products, that do a good job of displacing water on a metal surface — a real plus because rust may continue its attack if you simply coat oil over water. Water-displacing oils are formulated to drive away any moisture that may be on the surface they are coating, thus improving the protective effect.
I do not recommend silicone-based products. They work well for rust-prevention and general lubrication but can be vexing in the woodshop. Silicone seems to find its way onto everything in the shop either by contact with fingers or other carriers, or by atomization when sprayed. And, because nothing likes to stick to silicone, it will interfere with glue adhesion and finish application when and where you least expect it (so called “fisheyes” in a paint or varnish surface can be caused by a number of contaminants. Chief among them? Silicone droplets). The safest solution is
strict avoidance: do not allow silicone in your shop in the first place. Ever. Period.
Conversion
The conversion defense against rust is not as simple as rust-preventative coatings; however, there are a number of rust conversion chemicals that can be applied to iron or steel that convert any iron oxide present (and it’s there even if you can’t see it) into a stable, firmly adhering layer of iron phosphate or iron tannate. These chemical converters can be painted or wiped on, some form a film that acts as a primer for additional coats of paint. It is important to note that any chemical converters that create a film are usually disqualified from edged-tool protection tasks because any coating would coat the sharp parts of our tools.
Gun bluing and Parkerizing are surface treatments that are used to rust-proof firearms. Bluing is a controlled oxidation of the iron on the surface, converting iron to a black form of iron oxide, which is a more stable molecule that occupies the same volume as the un-oxidized iron, forming a protective coating on the steel surface. Parkerizing was a brand-name electrochemical phosphate conversion coating popular until the 1940s that has been replaced by other phosphate conversion processes. Blued and Parkerized surfaces are still somewhat porous, however, and will only prevent rust if the surfaces are kept oiled, consequently, we’d best call these conversion defense methods “rust-resistant”.
In addition to chemical solutions that coat and convert a surface, there are a number of vapor phase inhibitors or volatile corrosion inhibitors (VCI) that are dry chemicals that vaporize very slowly. These chemical vapors neutralize the available ions on the steel’s surface, which prevents the interaction of oxygen with the metal, which then inhibits rust formation. VCIs are commonly available in rust preventative
wrapping papers or small containers that can be placed inside tool chests, etc. The protection is only a molecule or two thick but that’s enough to help prevent rust in enclosed, storage-type situations. When the tool-box is opened, the vapors escape of course, but they refill the space as soon as they’re closed back up again. Volatile corrosion inhibitors will eventually evaporate, so it is important to follow the manufacturer’s recommendations for periodic replacement to insure ongoing protection.
Enclosed spaces such as tool-boxes have historically been rust proofed by the addition of camphor blocks or naphthalene moth-balls. These are oilbased, solid products that sublimate (vaporize without going through the liquid phase) at low temperatures and permeate the enclosed space depositing a thin layer on the tools, which in turn protects the tools from contact with air and moisture (if you can stand the odor.)
Basically, rust prevention is achieved by either keeping your steel dry, preventing water and oxygen from contacting the tool you wish to preserve or by changing the iron to something that reacts less readily with oxygen. You can turn the iron into iron phosphate, or coat it with plating, paint, grease, wax or oil. Or, knowing that rust never sleeps — you can maintain the vigilance required too keep your tools scrupulously dry, avoiding the frustrating and time-consuming problem with rust and corrosion. Your rust-prevention efforts are part of an age-old continuum of defense against oxygen’s evil efforts to ruin our stuff — you are a member of an ancient battalion for the forces of good.
Next week: Counter-attack using chemical and electrolytic action!
Linda: Do you make your own handles?
The Sharpening Blog 