Monday 9 July 2018
Having problems with your sharpening? Not always getting the edges you think you should? Are your results hit and miss? Confused about the various tools and systems available? Then read on! Over the next three articles, my aim is to demystify sharpening for you.
This article is a review of the basics you must master and consistently execute every time you sharpen a tool. In future issues, we'll deal with some technical stuff to help you select a good sharpening system.
Perhaps the best starting point is to ask “why, amid all the information available, do people fail to become consistently good sharpeners?” Why are so many seemingly put off by something that is easier to learn than many other woodworking techniques?
My early sharpening experience was notable for a lot of frustration and confusion. Based on student feedback, the experience of many beginners is similar. Many have not used a truly sharp blade, experienced what it can do or watched an expert at work. Moreover, it seems beginners are good at getting in their own way, throwing up mental blocks that further confound matters.
As a result, I changed the way I teach. I overcame my own frustrations by refocusing on fundamentals, things I now refer to as 'sharpening essentials'. I was striving to make my sharpening better, faster and more consistent. These 'essentials' are now the core of my approach. A good tip is to have someone you know who is a really good sharpener show you a truly sharp blade and what it can do with wood. This small exercise will establish the goal posts for you – it's enlightening.
Attitude trumps equipment
This is the critical starting point. Sharpening is the gateway skill to fine woodworking; it's the single best thing you can do for your woodworking in terms of skill development. Sharp enables the skilful and precise use of hand tools, but you have to want it. You have to bear down and put in the time – the tools won't sharpen themselves.
Despite the resurgence of interest in hand tools recently and the proliferation of new products, nothing new has really happened. Serious woodworkers, whether professional or amateur, have always used available technology to maximum advantage. Think for a moment about the fantastic furniture made through the centuries before electricity and power tools – these folks could sharpen!
The so called 90/10 approach, or the fancy new moniker, 'hybrid woodworking', is not new either. Smart woodworkers have been using machines for years to do the grunt work previously done by apprentices. Adding finesse and personalisation to the job was the most skilled work done with the best tools. Having committed yourself to the journey and with sufficient time at the bench, magic will happen and a new world will open up.
Sharpening is not difficult
Sharpening has been made to appear complicated and therefore difficult. The cause, for the most part, is because it hasn't been taught or written about correctly. Very often, basic principles have been glossed over and people looking for guidance without the benefit of an experienced master/teacher are left wanting. Sharpening should be fast, effective and repeatable; it can even be enjoyable but that might be a stretch!
If it achieves all those things, then it will be efficient. If your approach to sharpening is not all of these things, then it will be a frustrating chore you'll want to avoid. If you avoid sharpening, then you won't be any good at it.
The right order
We will become better sharpeners, and better woodworkers, when we sharpen our tools when we know we can make them better, not when they are dull and useless. Stop when the tool no longer does what you need it to do, touch it up and go back to work. Don't risk a dull blade slipping or causing tear-out.
The corollary to the sharpen-often-approach is that you should sharpen to the degree required by your work. Just because one person sharpens to a supremely high level and can take a shaving .0005in thick doesn't mean you need to do that all of the time. Make your tools sharp for the work you do and and don't set yourself up for disappointment – and extra work – by looking for perfection from every tool.
Keep it simple
In my opinion, the equipment is more or less irrelevant. In a world driven by retail consumption, this is of course heresy. Ignore those people who would make sharpening complicated. There are numerous equipment options and methodologies; pick one that suits your preferences and circumstances. All the well-known methods work. Do a little research, seek advice and recommendations; wade in and give it a go. Stay committed to the one method long enough to achieve a comfort level and consistent success. Don't worry, you'll likely try something new as your experience and woodworking needs change.
While there are many good honing guides on the market, I never use one and I consistently achieve high level results very quickly. I respect honing guides but they must be put in perspective. None of them are perfect. Honing guides are slower, more fiddly and fail to cover the required range of sharpening situations, e.g. short or narrow blades. Our forebears never had honing guides and they managed just fine: it's more important that a tool be sharp than look pretty, that you sharpen it when it stops performing and that you can get a fresh edge quickly.
Having said that, I do believe that beginners should consider using a honing guide because it's more important for them to achieve success during their first efforts and not be put off. I do also encourage more advanced sharpeners to lay aside the training wheels at some point. Freehand honing is quicker and, I believe, makes for more adaptable sharpeners. Let's not forget that many of the tools we use simply cannot be sharpened with a honing guide because of their shape or size. Sharpening will simply stop being an issue allowing you to get on with the important business of making tools dull!
Use a grinder
I struggled for years without a motorised grinder, actually, without any sort of grinder. One of the frustrations I experienced in the early days was the amount of time I spent shaping primary bevels and repairing damaged edges. Now I own three grinders, each set up for different work. It took quite a bit of practice to acquire 'the touch', but now a nicked edge takes 30-60 seconds to repair. Touch up a hollow ground primary bevel in around 1-2 minutes. I've also made scrub plane blades for old No.4s in less time than it takes to describe and even made a nice matched pair of 6mm skew chisels for dovetailing. Jobs like these have become relatively pleasurable without consuming enormous amounts of precious workshop time.
Any kind of grinder will do but those designed or modified specifically for sharpening will serve you best. Don't want to cope with the sparks, heat and dust of a regular grinder? Water cooled units like the Tormek are popular in pro shops – there are hand cranked units in the antique world. A coarse diamond stone is a good alternative for those with minimal requirements or who need portability.
Develop good habits
If you are using waterstones, lap them accurately and often – every 5-10 minutes of use. Not lapping is the single biggest cause of frustration for those who are otherwise trying hard. Lapping when you should means your stones will never be seriously out of true. Our sharpening will be faster, more precise and more consistent.
There are lots of methods for lapping – I think those special grooved stones are overrated. If you already have a coarse diamond stone, then you're set. Sandpaper on float glass is popular and effective but personally, I use an abrasive mesh used for sanding drywall, also on glass or granite.
Lap tool backs properly
I'm not a fan of the so-called 'ruler trick' as I'm not convinced it saves any time. If plane blades are so badly out of flat, perhaps it's best to get a new blade. New blades from good makers are usually already lapped flat to a high spec and can be polished up quickly. In my opinion, the ruler trick is only beneficial for old blades that are thin and difficult to get absolutely flat but can be made serviceable. Chisels, of course, must always be lapped flat – see benchmarking accuracy article in F&C 221.
You must get a consistent burr at each stage of the honing process and remove it before moving to the next step. That burr, or wire edge, is your indication that the two sides of the soon to be sharp edge have met. A thin bit of metal folds over, felt as a bit of wire. Often it can be seen as well as felt; this is the sign that the tool is as sharp as possible with that particular grade of abrasive. Make sure it's consistent: more strokes will create a bigger burr but will not actually make the tool sharper. Chase – polish – the burr with a couple of strokes on the back of the blade on the fine stone.
If you are using waterstones, then hone in a pattern that equalises wear on the stone as much as possible. Figure-of-eights and racetracks work. Moving the blade on and off the long edge when chasing burrs works. There is no need to aim for perfection, however, because you will be lapping the stone frequently anyway.
Honing wide tools
Hone wide tools before narrow ones; this will allow you to minimise wear. If possible, use the edges of the stones for narrow tools.
Sharpening more often actually means you will sharpen less! Think about it. If you stop when the tool is not performing the way you want, the dulled edge can usually be picked up on the fine stone in a matter of a couple of strokes. Don't bounce around between various sharpening media and methods without mastering any of them – this can take years. Stick with one thing long enough to make it work for you. Be patient, practice and persevere.
Don't get hung up about the exact numeric value of the bevel angle. Some people are obsessed about this and it's been a serious disservice to woodworking in general and beginner sharpeners in particular. For most tools, a primary bevel of between 25-30° is appropriate; add a secondary bevel of 3-5°. The primary bevel requires no work off the grinder or coarse stone, so go straight to the secondary bevel. There are no in between or so-called tertiary angles. This is really simple.
Efficient sharpening system
Create an efficient sharpening system and, ideally, a dedicated place to work. You will be more encouraged to sharpen when you know you should if your gear is already set up or can be made so very quickly. In other words, becoming a better sharpener is mostly about attitude and technique, considerably less about the equipment.
Remember – a sharpening medium or methodology is just that – a medium. Whether it's sandpaper on glass, waterstones or diamond paste on MDF, the blade doesn't really care. What you should care about is the fact that all of the available sharpening media have their pros and cons. Some are more effective under given circumstances than others; some are more efficient than others. At the end of the day, the wood is going to see a sharp blade and it isnâ€™t going to care how it got that way.
If you aren't getting the results you expect but you are using a 'recommended' method, it doesn't mean you should try something else. You don't necessarily need to buy those new stones or that new gadget. Quite possibly you need to back up a step or two before you can go forward. Refocus on the fundamentals and try harder. At the very least, ask a friend who is a good sharpener to evaluate what you are doing.