Graham's Guide to Selecting and Using Power Carving Tools

 

INTRODUCTION

The ready availability of good quality power tools at low prices over recent years has opened up a whole host of creative possibilities to the bonsai hobbyist. When I started carving over 25 years ago we were not so lucky or spoilt for choice. Put simply power carving uses high speed rotary tools and a variety of cutters to allow us to easily shape wood in a creative way. More traditional methods of carving using hand tools certainly have their place but within the context of a live tree and particularly where it is necessary to remove large volumes of wood they are unsuitable for a large number of reasons. Within this article I intend to introduce what I have found to be the best and most versatile tools and techniques currently available and based on my own experience using these tools almost daily.

The choice of wood carving tools and cutters available today is vast. Before spending money it is important to ascertain which tools are right for the job you need to do. There are some unique facets to carving bonsai that are not of concern to conventional wood carvers and these largely dictate how we work. Therefore not all wood carving tools are suitable for use in bonsai tree carving work. Consider that often the wood we are carving can still be green and alive. Also we have to carve types of wood not well suited to regular wood carving when still containing sap, like pine and larch that are soft resinous woods. Sometimes the wood can be degraded by decay and fungal activity; we also have to deal with stripping bark, either alive or dead. So, I would like to differentiate the types of carving tool bits into two main groups……

ABRASIVE ACTION TOOLS

abrasive action tools

I.e. Structured tooth tools, flap wheels, rasps and wire brushes.
These are great tools for finishing work, smoothing, graining and texturing and working with harder woods not containing excessive resin.

 

CHIP CARVING TOOLS.

chip carving tools

I.e. Tools with a small number of large cutting ‘teeth’ which remove coarse chips of wood rather than fine dust like abrasives do.
These tools remove lots of wood quickly and are used for shaping and hollowing in many forms.

 

CHOOSING POWER CARVING MACHINES FOR BONSAI

Because we are considering power carving we are going to need a machine to ‘power’ the cutters we choose. Our choice of machine is largely dependent upon the size of work to be completed. For instance it would be possible to create a huge hollow in a massive trunked bonsai with a small hobby machine using a micro burr but you might be very old before the work is complete! Whilst there are a number of alternative format machines available like long neck angle grinders, flexibel shaft machines and belt drive grinder attachements here i will be focusing on more conventional die grinder/Dremel style machines which are readily available at good prices and offer extensive versatility for completing a wide variety of tasks.

It is important to bear in mind the running speeds of our tools. Most chip cutting tools have an optimal running speed of between 10-18,000 RPM. So things like electric drills are woefully inadequate. Smaller cutters and abrasives will on average run better at 15-25,000 RPM. Tiny abrasives like diamond points are best at 30-45,000 RPM. Always follow the guidance supplied with the cutting bit you are using.

Power carving machines can be divided into two main categories for our purposes.

 

1 - Larger machines (Die grinders) will run cutters having a ¼” or 6mm shaft to mount them.

Makita Gd0600
Die grinder for large shaft tools

 

 

2 - Smaller machines (Multi/hobby tools, Dremel) will run cutters having a 1/8” or 3mm shaft to mount them into the business end.
 

small power tool

Hobby machine for small shaft tools

 

Obviously this is not an absolute distinction but it serves our purpose. For instance a machine that can handle a ¼” shaft bit can be adapted easily to run a 1/8” shaft bit. However a small machine like a hobby tool does not have the capacity or the power to run the large cutters.

A flexible shaft machine like the Foredom SR is capable of handling tools with shaft sizes from 3\32” to ¼”. However due to the considerable cost of this excellent unit I assume that by the time you are considering buying one you will be well versed in the subject.

If you are new to bonsai carving work I would recommend starting out with a small machine like our Hobby Tool or GMC Multi-tool. With the right attachments this will allow you to complete some fair sized projects on small to medium sized bonsai. You will have the chance to gain experience with power carving and the benefits it can bring to your bonsai without spending a fortune. Also consider that your money will not be wasted because, even if you choose to move to a larger machine in the future, your small machine will still be needed for detailing and finishing once the large unit has done it’s work. A flexible shaft can also be purchased to add to these smaller machines. Once you gain confidence with using this attachment I wager it will become a permanent fixture of your bonsai workshop.

Small machines do have their limitations in terms of the size of cutters they can run, small motors simply do not produce the torque required to drive larger cutting bits. Also their ‘duty cycle’ i.e. how long they can run without a cooling off period, many small machines offer a speed of rotation considerably higher than we require. Any machine running flat out all the time will have a limited life span.

For large projects on big bonsai trees you are going to have to invest in a more powerful machine designed for the job. Something like the Makita GD0600 die grinder may seem expensive but consider these are full cycle industrial machines designed to run day in day out for years with very little maintenance. The Makita die grinder has become a perennial favourite with bonsai carving experts across the world. The rotation speed is just right as is the torque produced and the machine is quiet and smooth and given some respect can easily return thirty years of service. The machines relatively light weight, slim design and operating speed make it our most popular “entry level” large power tool. In comparison with other brands of die grinders and other models within the Makita range the GD0600 currently offers the best value for money on the market.

So as a rule of thumb, large machines for large work and the small machines for small projects, detailing and finishing work.

 

 

CHOOSING WOOD CARVING CUTTERS – SHAFT DIAMETERS

Our choice of cutting bits is dictated by what power tool we have as detailed above. The shaft is the part of the cutting bit that actually mounts into the power tool. There is a limit to the size of head that can be mounted onto a shaft of a given size, high speed rotation develops considerable stresses and the bigger the size of head and speed of rotation the greater these will be. Over the years I have seen many poorly designed (often expensive) tools where the head to shaft ratio is wrong and many of those tools have failed withing minutes. Only buy well known, tried and tested brands of tools from reputable suppliers. There are a lot of folk knocking up a few tools in their lunch time at work and selling them cheaply. Where cutting tools are concerned reputation is everything. The cost of a well designed and tested tool is forgotten long before it reaches the end of it's life. However you can get plenty of time to consider the folly of using poor tools as you sit waiting for medical attention in A&E or the ER.  (It is very important to make sure the bit is well secured into the machine for safety. Cutting bits move at very high velocity and can come out of a machine at high speed if not mounted correctly, obviously if this happens the risk of personal injury can be severe and the results very serious indeed. Also if a bit is not mounted properly in the machine it can vibrate badly, this can cause damage to the machine, the cutter and the work. Collets are rarely cheap but using the wrong one could end with a visit to the hospital so don’t try to ‘make do’. Buy the right part for the tool you are using, keep them clean, lightly greased and replace if broken. BE SMART!

Cutters usually mount in high-speed power tools by virtue of a collet and nut system that clamps powerfully around the entire circumference of the mounting shaft. Never use any kind of screw chuck system as sometimes supplied fitted to Dremel machines. With anything other than tiny cutters, stones and diamond points this method of mounting is simply dangerous. A collet is a small precision part with a bore that should exactly match the shaft of the cutter being used. With the shaft of the tool inserted into the collet it will clamp itself tight onto the bit when the securing nut is tightened. Most small power tools use a collet of 1/8” or 3.2mm this is by far the most popular shaft size and the bulk of good carving tool bits available use this size. This is a safe and strong enough shaft to run smaller chip cutting bits and abrasives. There are often a variety of collet sizes supplied with small power tools however for wood carving these are of little interest to us and best suited to mounting small abrasives and micro cutters.

collet and nut mounting
A standard collet & nut system

 

3 jaw chuck

Don't use a 3 jaw chuck for high speed work 

 

Larger power tools within Europe generally come with a 6mm collet (1/4" in the USA and Australia). This will mount European tools with a 6mm shaft, however it is NOT suitable for securing ¼” tools. Any larger power tool manufacturer will have alternative size mounting collets available for it's machines. For alternative collets to suit the Makita GD0600 Click here. It is a common miss-conception that ¼” and 6mm tools are interchangeable. However ¼” is in fact 6.35mm and a 6mm collet will not accommodate that extra fraction of a millimetre. It may be possible to force the larger shaft a little way into the collet but this can damage the collet and is VERY DANGEROUS. Conversely it is possible to mount a 6mm bit into a ¼” collet and generally the collet will take up the slack when tightened. However the cutter will have excessive run out (will not run true) and this WILL cause damage to the bearings in your machine in time and possibly bend the shaft of the cutter you are using.

shaft and collet fitment
Collet too small

correct fitment
Correct fitment, fully inserted 

 incorrect fitment
Result of incorrect fitment

IT IS VERY IMPORTANT TO UNDERSTAND THIS ISSUE SEE -  Important Information on Mounting Cutters in Power Tools

 

CHOOSING CUTTERS - THE BASICS

Any wood carving project is invariably going to require a number of tools to complete it. Sadly it's just not possible to buy a power tool or cutter combination that will allow us to 'do everything'. Every project is different and everyone likes to work in their own unique way and so invariably a number of tools will be needed and everyone will like something different. Later on I explain what's in my own personal toolbox and why but in time yours will likely evolve in a different way. In the past I have acquired tools I initially thought to be useless only to later add them to my 'MUST HAVE' list. It's a proven fact we do not learn by hearing or even seeing but by DOING. The more work you do the better your work becomes as we hone our skills so never be tempted to pass swift judgement on any new tool until you have spent a year using it as a part of your tool kit. A skilled craftsman always gets more out of his tools than the inexperienced novice.

Most carving projects have two distinct phases. Assuming you are dealing with material that has large cuts, big branch stubs and, or a trunk chop to deal with or large areas of deadwood this will need 'BLOCK CARVING' or roughing out in more conventional parlance. This work normally requires the removal of large amounts of material, hollowing and external shaping and is best done with chip carving tools.

The second phase of carving involves refining the shape of our roughed out work, adding fine details like graining and cracks and smoothing out tool marks to create a very natural final appearance. This phase can also include cleaning away dead bark or degraded wood where yamadori is concerned. This second stage work normally employs finer cutting tools, abrasives and brushes of various kinds.

 

BLOCK CARVING TOOLS FOR SMALL SHAFT MACHINES

Until recently there really was not any tools I could put in this category. I have seen some offerings from European retailers but having bought and used them I was not even close to being happy with the tools performance, most had a cut rate that was simply too aggressive making the tools unsafe and several failed on me in the first hour. The result was that I had to design and manufacture my own cutter and even though I say so myself the results were pretty impressive.... enter the latest addition to the Terrier™ kennel....

The Little Terrier™ DH This innovative carving tool overcomes the largest single drawback of using small power tools, the small shaft. The Little Terrier DH is a large shaft cutter that mounts onto a small hobby tool or Dremel in a unique way. The head geometry allows the powertool to drive an incredibly effective cutter without damaging or overloading the motor or suffering the considerable flexing of the small shaft that would normally be the case with such a powerful performance cutter. What this new Terrier effectively does is convert your little rotary tool into a formidable die grinder with the cutting capacity of a much larger machine. The combination allows a small machine to tackle jobs that were previously unthinkable. The Little Terrier DH has tungsten carbide cutting teeth that can be easily rotated to present a fresh cutting edge once they become dull and are replaceable entirely once they are completely worn out. However this is not going to happen very often. In development we ran the same set of cutting tips for a 12 hour non stop period cutting seasoned oak and olive wood without any loss of cut rate performance. At the end the cutting teeth were still good and it was still possible to rotate them TWICE before the end of their life. Assuming you do not cut into stones, old screws or other detritus and in normal hobby use we think the Little Terrier DH cutting tips will last indefinitely and even then are cheap to replace. There really isn't much this tool won't get to grips with. Cut ANY wood no matter how hard, how old, or how full of sap. Use for external shaping, hollowing, dressing cuts or stripping bark. We know it's a bit expensive but this tool is MADE IN THE UK by skilled British engineers, it's safe, effective and does exactly what we say it will. Buy right, buy once!

Little Terrier DH

The Little Terrier™ DH Turns a hobby tool into a wood eating monster

 

BLOCK CARVING TOOLS FOR LARGE SHAFT MACHINES

Unlike smaller power tools, we are spoilt for choice when it comes to good cutters for larger shaft machines. However exactly as with the smaller tools there are some very poor and even dangerous tools on the market. Again your only defense is buying tools that have a proven track record and an established reputation backed by a good company. If you buy cheap carving tools you get just that, cheap carving tools and you may well have plenty of time to rue the day you decided to be frugal whilst you are laid up recovering. Then again I have bought many expensive tools that have failed on the first use out of the box only to have the supplier blame me and walk away. A few years ago I was in NYC conducting a workshop and was handed a power tool within which was mounted a 4" long cutter from a well known European seller. I was told "Use this, I just got it and haven't fired it up yet". I duly fired up the machine and instantly the cutter folded through ninety degrees leaving be barely able to hold onto a viciously thrashing 25,000 RMP windmill capable of gutting a man in a millisecond. Fortunately someone had the presence of mind to pull the plug and we all fell to our knees thanking God nobody had been disembowelled, this was probably the worst power tool incident I have experienced and I started using power tools before I was ten years old. I have seen several tools from the same seller fail in the hands of many students with considerable carving skills. These tools are often sold as conforming to all European standards and in terms of the cutting head geometry (which is what the regulations apply to) they may well do but there are more significant issues to be concerned about. I have also seen a lot of very cheap cutters and burrs available from places like Ebay which come from places like China which are often poorly made, badly assembled or of inferior materials. NOWHERE is it truer than in carving tools that YOU GET WHAT YOU PAY FOR.

In light of the above the only tools I can recommend are those I have personal experience of and know them to be safe and effective over the long term. These are the tools we choose to sell rather than persuing a quick and easy buck selling junk.

THE TERRIER™ – Available for close on ten years now this unique cutter was specifically designed by us for bonsai carving work. Since it's introduction the Terrier has made it's way to every country in the world and is in regular use by some of the worlds best wood carvers, chainsaw carvers and wood turners not to mention several of the most skilled bonsai artists like Kevin Willson. Tried and tested by several respected wood carving magazines. The Terrier has a superb pedigree second to none. Manufactured in the UK by highly skilled engineers with up to the minute CNC machinery and proven across many thousands sold worldwide. Three replaceable tungsten carbide cutting inserts on the small versatile head simply vaporise wood without effort. You can create shapes curves, sweeps and hollows almost effortlessly as wood vanishes in front of the tool. A very refined and easy going tool without any hint of aggression in it’s cutting performance. The long shaft makes this one of the most versatile power carving tools in the world. Guaranteed to be a revelation this tool has become the standard by which all others are judged. Only available direct from Kaizen Bonsai for worldwide distribution. If you go to buy one of these and don't hear our name then it isn't ours and is a rip off copy which could just rip off more than your wallet.

THE LITTLE TERRIER™ - Following on from the success of our Terrier™ it quickly became apparent that we needed a longer shaft tool for confined spaces. The result was out Little Terrier™ introduced in 2009. this ground breaking tool has again spread around the world with quite remarkable success and not a single one has EVER been returned to us despite having sold many thousands. The Little Terrier™ has a 15mm head with two tungsten carbide cutting inserts. The shaft is longer than the Terrier™ allowing much improved access when working in a confined spot. The long shaft and small cutting head make the Little Terrier™ the best tool for creating and opening up hollows and cutting holes. A chip limiter prevents the tool from 'digging in' to the work. A light action produces a fast delicate cut but with a little more pressure the tool bites harder without fear of it 'grabbing' or kicking back. A formidable British made tool with all the attitude of it's namesake, The Little Terrier Grrrrrr.

4” BALL NOSE CARBIDE CUTTER – DO NOT let the benign appearance of this tool lull you into a false sense of it's innate ability. This is No3 on my list of MUST HAVE bonsai carving tools. A simply formidable tool that will simply TEAR through any wood it comes into contact with. It cuts forwards and sideways and opens up deep holes faster than you can think. Definitely not for the feint hearted. Made in the USA from 100% fine grained carbide.

THE ROUGHING CUTTER - If you are a little on the timid side the above 4" tool might not be for you. However this slightly smaller but similar tool just might fit the bill. A spectacular cut rate and ability to open up holes as fast as a bullet. Also our preferred tool for ripping through very soft or wet woods like green pine, larch and elm. Made in the USA from 100% fine grained carbide.

PROTEUS - A nice tool that bridges the gap between chip cutting bits and abrasives. The end of the tool consists of two teeth that open up hollows very quickly. The side of the tool is a very coarse rasp that allows it to move sideways through wood in a very controlled manner. A formidable tool and a very popular one with our customers.

Whilst only listing five tools in this section I have completed every large project I have done in the last ten years with these tools and whilst I do have other cutters in my toolbox most never see the light of day. If you can't do the job with these tools you just might need something with an engine attached! 

 

See some of our carving tools in action

ABRASIVE CUTTING AND FINISHING TOOLS

Once you have completed block carving work it’s time to create some detail and texture before burnishing the final result. However just because abrasive tools do not have the rapid cut rate of chip carving tools do not be fooled into thinking they are any less effective or important in the process of producing a beautiful end result. Most mainstream power woodcaving tools are abrasives in some form or other. Some are good and some are not so good, over the years i think I have probably used everything on the market and have wasted a lot of money. However a few tools have proven to be exceptional and remain firm personal favourites.

A well structured and designed abrasive tool can be a joy to use. They offer a very smooth and controlled cut rate with great manners. Large tools in coarser grades can be a good alternative to chip cutting tools for those who do not have the constitution to deal with their aggressive nature or the strength to hang on and take control. It's a bit like comparing a pit bull terrier with a golden retriever, both have their place and both have their supporters and whos' to say who's wrong? Abrasive tools can be a very versatile force in carving but need a firm hand since they do have a tendancy to leave your work looking smooth and soft not unlike the Pillsbury Doughboy. 

SABURRTOOTH® WOOD CARVING TOOLS – Until the advent of these very special tools I had very few abrasives in my own toolbox. However since the release of the Saburrtooth range I have a great many more. I was sent a sample several years ago that sat in my desk drawer for about eighteen months before I found I needed it. Since then I have been using these tools for every project I complete. Saburrtooth offer an extensive range of tools from tiny small shaft versions for hobby tools through 1/4" or 6mm shaft versions up to 2" diameter and going to larger disks and buckets right up to 4" diameter and all in a variety of abrasive grades. Saburrtooth tools have a unique tungsten carbide tooth structure with an open format that resists the loading (clogging up) normally associated with abrasive tools in wood carving. Whilst some degree of build up may occur in certain materials the tool continues to cut regardless. As a general rule use finer grades for harder material and the coarsest grades for soft materials. Saburrtooth offers one of the best ranges of wood carving tools available to the hobbyist. Buy one and find out for yourself.

SABURRTOOTH® SMALL SHAFT BURRS, FINE GRADE & COARSE GRADE

SABURRTOOTH® LARGE SHAFT BURRS

SABURRTOOTH® 4" CARVING DISKS

SMALL CARBIDE TOOLS - Over the years I have gathered up a selection of very special little carbide carving tools for bonsai work. Obviously being carbide these tools offer great value for money by virtue of lasting a really long time. Whilst this type of cutter looks quite unassuming don't be fooled into thinking they are a bit naff. The versatility and cut rate offered are quite exceptional, the work we have managed to produce with these tools is quite remarkable...

SPIRAL WOOD CARVING TOOL - One of the most impressive small tools we have been able to find. The two cutting flutes cut upwards thus pulling chips out of the hole, this prevents clogging and overheating of the cutter. Without doubt this little cutter removes wood faster than anything in it's class. Great for ripping out large holes or carving detail. A very strong little wood cutter with a nice refined character that is very controllable and cuts very cleanly without effort. Also available in an EXTRA LENGTH version.

CARBIDE DETAIL CUTTER - One of the most useful all round carving tools to use in your Dremel or small hobby tool. Not only will it drill holes but it cuts grooves and makes small hollows when sideways pressure is applied. Using a little water for lubrication these twist bits will also drill holes in stoneware pots and rocks for attaching anchor wires. Very hard and very strong but can still be sharpened using our Diamond Pen.

OTHER SMALL DETAIL CARVING TOOLS - Another couple of tools I have to mention for detailing are our Pinnacle and little rotosaw. Whilst not carbide these are USA made quality high speed steel which is pretty impressive when it comes to wood cutting and do have the advantage of not being quite so brittle as carbide.

PINNACLE DETAIL CARVING TOOLThis innovative little carving bit made of high tempered carbon steel has 2 tapered flutes that draw chips out of the work cleanly so that you can see where you are cutting. Great for deep internal work and precise detailing in wet or dry wood and plastics.

ROTOSAW GROOVING TOOLMaking grooves and texturing the surface of previously shaped wood is one of the most important parts of carving bonsai trees. Blending in newly cut wood with raised grain detail is vital. This versatile rotosaw is perfect for the job. If run into the surface it makes a slim groove or brushed delicately at a precise angle it makes a nice V groove. Used in conjunction with the Pinnacle this is a versatile combo that will produce some impressive work.

WOOD CARVING BURR SET - Don't let the low price fool you. These are superb HSS tools that are perfect for cleaning old deadwood, adding details, shape and texture. This little set should be in everyones tool box, they're certainly in mine.

SANDING DRUMS & FLAP WHEELS – Before using these I tend to run over the work with a small gas torch to dry the surface of the wood and remove wood fibres. Good tools for smoothing and taking out cutting tool marks an essential stage in any carving project.

ROTARY WIRE BRUSHES – Finding quality rotary wire brushes is tough. You will either be paying crazy money for branded itens or next to nothing for something that looks good but only lasts a minute or two. Over ten years ago I found a manufacturer of top quality small shaft brushes in the USA. Since then we have sold thousands and continue to do so. These little brushes are extremely impressive and absolutely invaluable for any bonsai project you might be contemplating.

As well as the above list we offer a huge variety of tools for every conceivable bonsai carving job. All of these tools have their place but the list above is what I would consider the absolute bare minimum you will need for completing most projects involving power tools.



EXTRA LARGE POWER CARVING TOOLS

On occasions it can be either desirable or necessary to use something a little larger than the tools I have detailed above in order to complete a big project or one with some unusual characteristics. The next realistic step up from all of the above listed rotary tools is the move to 2" diameter tools. Some of these, like the SABURRTOOTH BUZZ OUT, can either be mounted onto shafts or directly onto some specialised machines. Others like the SABURRTOOTH 2" DISK will bolt directly to Arbotech's Mini Carver. 2" tools offer a small step up but in reality do not offer increased cut rates that are exactly worth the investment in the power tools required. I have used the Arbotech Mini quite a bit and it does offer some scope for easily making shapes that die grinders can't but I have not used it now for a few years and rarely feel the need to dust it off. Some folk will love this format but then everyone likes something different.

The next step up we can make is to 4" 100mm disk type tools designed to run in the common or garden angle grinder, a much maligned and overlooked power tool. 4" angle grinders are one of the cheapest power tools commonly available and with a little skill can be used to GREAT effect. If you are buying one do not go for the fastest rotation speed, 10 to 11,000 RPM is plenty. We put together an ANGLE GRINDER PACKAGE that's an absolute steal to get you going with these larger units. Personally I would remove any side handles, they just get in the way most of the time. However DO NOT remove the blade guard, EVER. Sure it will get in the way but it's there for a reason. Firstly your hands tend to move forward as you work and sooner or later will make contact with the cutting disk. Secondly, should a disk fail, explode or simply come undone whilst not using a guard and your hands are close by there is going to be carnage. I have seen a finger removed in less than the blink of an eye by an exploding grinding disk. Our steel disks are a lot safer than those composite materials but why take the risk? A 4" grinder will run our SABURRTOOTH 4" POWER CARVING WHEELS one of the most effective yet safe power carving set ups I have had the priveledge to use. See one in action in the video below. Another SERIOUS disk you can add to a 4" grinder is Arbotech's Industrial Woodcarver, at close to a hundred quid I think it's good value for what it does. I use this a lot but always with trepidation. In all seriousness I can't recommend this tool unless you are A. Very experienced or B. Have some big nackers.

 

See the big Saburrtooth disk in action

 

Last of all in this section I have to mention chainsaws. Years ago a few silly buggers got themselves a reputation for being butchers by using chainsaws on bonsai in public. That was in the days when, in order to become of weight in the bonsai community all you needed was a big tree and a gimmick. Nobody really grasped the idea of quality back then, big was beautiful, it was the 1980s after all. There are some well documented examples of the carnage a chainsaw can wreak on an unsuspecting bonsai tree but unless you are extremely well versed in the use and mechanics of these tools PLEASE don't use one. I recently bought a stunning little 10" 25cc topping saw for less than £80. I have no idea how, or why, anyone would do such a superb piece of kit for such a low price but i'll make good use of it but take my advice and keep chainsaws away from live trees.

 

TUNGSTEN CARBIDE OR HIGH SPEED STEEL?

Over the years I have used hundreds of different tools for bonsai power carving work. I categorically recommend using tungsten carbide tools. They cost a lot more than their high speed steel equivalents but will last indefinitely if used with care and consideration. The primary downside to using carbide tools in freehand work is the fact that the metal is more brittle and unless good control is maintained breakages can occur. However with a little skill and experience breakages quickly become a distant memory.

High-speed steel is an impressive material and is quite capable of cutting mild steel so wood really does not present it with much of a challenge, it also has the advantage of being a little more ductile than carbide. Always keep in mind that a high speed steel tool should not be allowed to get extremely hot, once it becomes blue with heat the hardness of the material will be compromised and YES I have seen folk run these tools to that extreme temperature. Use HSS tools at a slower speed, use less pressure, don't allow the tools to run in a hole filled with compacted dust and chippings and clean if they become clogged. This will all help the tool to run cooler, maintain it's cutting performance and ultimately extend the tools life.

Because of the intricate nature of most of the tools detailed here sharpening is rarely successful. Blunt tools tend to need more applied pressure to cut and that’s when accidents happen. Where a tool presents a nice straight cutting edge sharpening may be possible but only if you are skilled at such things. I have found the best tool to use is a very fine abrasive diamond hone that should be well lubricated with WD40 before gringing commences. Our Diamond Sharpening Steel is the tool I will generally reach for first.

HOW TO AVOID BREAKING CARVING TOOLS

High quality carving tools are made of high quality materials. This means they are strong enough to survive the rigours of what they are designed to do. Good tools are not made by muppets but people who know what they are doing. Tools are designed by highly skilled engineers who know how to specify the correct materials and how to use those materials in the correct way. The reason why tools fail is not because they are faulty, though some from amateur sources can be through poor design, manufacture or specification of materials, but because of mis-use.

DO NOT ABUSE CARVING TOOLS - A BROKEN CARVING TOOL IS NOT FAULTY IT'S BEEN ABUSED

Everyone is going to break some tools once in a while, it goes with the job. However a lack of understanding about how to use these things is ALWAYS at the root of a failure. Mine and previous generations grew up in a different world to that of today, we grew up with DIY and having to be ingenious in order to get what we wanted. In the world in which I was raised being able to do things like make and repair stuff was considered a badge of pride. If we did something and it failed it was OUR fault. Sadly today everyone wants to blame somebody else and consequently be compensated. Sadly in todays compensation culture folk are getting paid for accidents and other issues which are entirely their own fault. If you fall over on a slippery surface it's your own fault, you should be more carefull, it's your responsibility to see after yourself. The fact that somebody didn't put up a sign should not be reason enough for a slimy lawyer to get you paid whilst ruining somebody elses life.

Carving tools are CUTTING TOOLS. That means they have to be sharp and sharp things cut which makes them dangerous in the wrong hands. I have lost count of the times I have seen somone using a beautifully engineered and executed cutter like it was a rock. Just because power carving is powerful and noisy does not mean you have to act like a neanderthal every time you fire up. In the wrong hands carving tools can be devestating all around. I will never condone, or compensate clumsiness, ignorance or stupidity so please follow these steps in order to be safe and keep your tools alive.

1. Always mount a tool correctly and securely in the machine you are using, not doing so often causes instant failure.

2. Always respect the speed paramaters suggested by the manufacturer, if in doubt go SLOWLY. Like they always say 'speed kills'. In wood carving faster is NOT better. The slowest speed possible is always the best speed. Most people do not have the processing ability to work with formidable cutters at very high speeds.

3. New tools can be more aggressive than well used ones. Approach your work gingerly, do not apply pressure and do not put rotating tools inside small holes. HAVE SOME RESPECT.

4. If you have not used a tool before acclimatize yourself to it's unique character by using it, rotating slowly, on the OUTSIDE of some well secured scrap material. Cut that material in different ways with different strokes and in different grain directions. Once you are confident move on.

5. Never push hard or lean on a carving tool or put a poorly controled tool inside a hole 99% of breakages happen in these cases. If a tool refuses to cut a piece of wood do not just apply more pressure, this will heat up the tool and cause invisible damage and weakening, the answer is to approach the grain of the wood from a different direction. Often tools struggle to cut down into end grain, approaching from the side in a cross cutting manner will always work.

6. Hold your power tool close to you with bent elbows, never at arms length. Place one hand around the front of the machine with a very firm grip. Place the other hand at the rear of the machine. With the machine running rest the back of your hand, wrist or thumb on the work you are cutting in order to provide a secure pivot for the machine then, using the hand at the rear of the machine, tilt it gently so the cutter approaches the work in a controlled manner. I don't care who you are you cannot hold a rotating machine securely with arms outstreched, the cutter will snatch, run up your work and most probably break or cause damage.

7. Tungsten carbide is by it's very nature hard which also makes it brittle. This is not a fault it's the whole reason the material exists. Any carbide tool that is allowed to kick back, spit, jump or rattle around inside a hole is going to break. A broken tool is not faulty, it's been abused, faulty solid carbide does not exist especially from American or Japanese manufacturers where all of our tools are sourced.

8. High speed steel tools should not be allowed to get too hot. As soon as any discolouration occurs the tool is scrap. High speed steel will not usually break like carbide tools but will typically bend. A bent or broken tool is not faulty it's been abused.

9. All tools should be kept clean at all times. Tools that are clogged or no longer sharp loose their efficiency, this requires more pressure to get them to cut which ALWAYS causes failures.

10. Never use other peoples tools unless you are confident they are good and always mount them in the machine yourself. As i mentioned earlier you need to know what you are using is good and safe or you just might end up gutting yourself or worse, someone else.

 

CLEANING CARVING TOOLS

Bonsai carving work creates some unique problems for power carvers. One of these is the tendency for cutting bits to clog or ‘load up’ due to their working temperature and the often sappy or resinous nature of green wood. Keeping tools clean means they cut more easily without you having to apply excess pressure, this helps avoid accidents and breakages. Clean tools also run cooler which extends their life and reduces the load on your power unit.
Because tools have intricate cutting edges we cannot recommend using any type of abrasive cleaners such as wire brushes. It is certainly NOT a good idea to burn deposits from the tools. Our detergent TOOL CLEANER is a highly efficient solution that will remove the most stubborn deposits. Simply pour a little cleaner into a tiny container and soak tools overnight. Contamination can simply be wiped away with an adsorbent cloth and your tools will be as good as new.

SO WHAT’S IN YOUR TOOLS BOX?

My own collection of tools is a rag tag assortment of bits collected over a number of years.
For power I use one of our GMC tools and a Hobby Tool with a flexible shaft permanently attached and an old Makita 906. I also use a Metabo G700

Bits for the small machine include…

The Little Terrier™ DH

Weasel 100A 101B and 101C, sorry no longer available

Spiral wood carving tools in 2 sizes

Carbide detail cutter

Saburrtooth  Burrs in coarse grade in a variety of patterns,

Pinnacle, small wire brushes, sanding drum kit and sanding flap wheels.

 

For the larger machines I have…

The Terrier™

The Little Terrier™

Weasel 102B and 103 A & B sorry no longer available

4" Ball nose

The Proteus

Several 1/4" shaft Saburrtooth burrs

 

Graham Potter's bonsai carving tool box

As you can see from this picture there are a lot of other odds and sods I have gathered up over the last twenty five years. Most of these rarely get a run out but I know what they do and at some point I will need to just tha which is why I keep everything.

 

SAFETY PRECAUTIONS

Over the years I have done every stupid thing it's possible to do in a workshop. I have been to hospital more times than I can recall and have a good collection of scars. That sounds cool in retrospect but a few moments after you get battered it's not cool at all so be smart, use your head and work with tools sensibly because EVERY time you cut corners, make do or 'chance your arm' you are VERY likely to start parting company with lumps of yourself. If you are unsure about what you are doing get advice before starting out, preferably get yourself onto a supervised workshop with an expert if you can find one. 
Never take risks with any form of power tools.
Ensure cutting bits are mounted safely in your machine.
Never use a broken or ill-fitting collet.
Always wear eye or full-face and hand protection.
Take precautions against breathing dust.
Never exceed manufacturers recommended operating speed with any cutting bits.
Do not use excess force to drive a cutter.
Ensure power tools and cutters are well maintained and store safely when not in use.
Keep power tools and cutting bits away from children.
Always be mindful of bystanders when using power tools.

 

Graham Potter.
© Kaizen Bonsai Ltd 12/2016