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Accuracy and Tolerance

In discussing accuracy, I can’t help myself but to continue pointing out the two distinct differences between handwork and machine work simply because many see machine work as the more progressive and advanced way and handwork as primitively backwards and retro-thinking. My skills with handwork are highly developed, I know that, but many think that handwork takes years if not decades to develop when in actuality we can learn skills in a matter of weeks and then develop speed and efficiency using them over a number of years. So no, it doesn’t take many years at all, what can take years is learning about woodworking, wood, techniques and ideas.

I made this box in under one hour using only hand tools but with my wood planed and cut to size. The dovetails, hinge recesses to box wall and lid and the roundovers came from hand tools only. The tools? A square and knife, pencil, dovetail saw, chisel, chisel hammer, #4 Stanley plane, screwdriver. Oh, it includes three coats of shellac too!

I see nothing wrong with using a machine like a router for recessing a hundred hinge recesses all identically placed in like-kind doors and door stiles at all, but to recess three hinges in a door and stile, it seems to me like a sledgehammer to crack the proverbial nut. So too planing a door to fit within a thou’ without taking off the door to offer it to a power planer or a belt sander and so on. I would guess that the majority of those following my work have no way of setting up a machine shop and also see no reason to because they don’t mass-make anything and see no reason to set up a mass-making system. If they then pursue handwork they must develop many skills, many of which take only minutes to master and understand, but they have no choice but to develop sensitivity which is accuracy which is precision in the multi-dimensional ways I speak of. Instead of pushing the boundaries, they are willing to be constrained by them. They don’t throw off the restraints handwork demands but pull them on. It’s as if they sense the dullness two seconds before sharpening is needed. They know that without sharpness the knifewall will not have a crisp and precise edge but a sorely bruised and rounded one. The chisel will slide away from following the knifewall corner in its crispness and will slope away from it. They soon start self-correction because their demand for quality is governed by their self-awareness in the work and they feel for pressures and then the added pressure needed to work dull tool. You see the difference between the two distinctly different and generally unrelated camps of the machine worker and those using hand tools becomes self-evident to the hand toolist. He, she begins to know the difference between road-grader rigidity and the sensitivity of flex I have written on elsewhere in my blog. As hand toolist, we use mostly a handful of cuts to expedite our work rather than the thousands of cuts per minute the machines all rely on. For this to happen the tools must be sharp. If you are not going to sharpen in time and then sharpen accurately and sensitively you should just use machines. To be a hand toolist, you have to want to be skillful and if you want to be skillful you have to want to sharpen much of the time. This, then, is the paradigm shift we all ultimately make at some point in time in becoming progressive hand tool woodworkers.

Shoulderlines begin with knifewalls that come from a supersharp knife. There can be no compromise!

The knifepoint enters the surface fibres with only the most minimal pressure from either hand. It’s the gentle interaction between both that many forsake, yet to use more excessive force with heavy-handedness often leads to less control and slippage. Negating the use of a more sensitive pass over, into, and through the surface fibres carries with it a lack of self-confidence. What we need and rely on mostly is a multidimensional flex that responds to every rise and dips into the irregularities of density between each of the growth rings if growth rings are indeed present. As we gain sensitivity, we realise that every species we work with is different and no two are similar in any way. Our presence and sensitivity are indeed ever-present as we part the waste from the wanted with the finest and thinnest and straightest of lines I call knifewalls. Because tree growth in every species is different, each of the species produces different densities, different grain textures and we, the worker with hand tools, must define accuracy, sensitivity and sharpness throughout every minute that we work. If we stubbornly refuse to sharpen we refuse sensitivity to our work and we cannot work accurately to separate that part that must be taken away from that which will create the perfect joint line. Having just made 12 tenons, I fit each to its partnered mortise. All 24 shoulder lines rest gapless as the joints seat. Every shoulder square, every shoulder parallel to the opposite side, all frames uncompromised by inaccuracy from the final mallet blow. The frames rest square with no need for checking. For 56 years, this has been my ever-present goal.

To plane adjacent surfaces in oak the plane must be as sharp as possible to level everything within one-thousandth of an inch.

There is of course that spiritual element to craft that no man or woman seems apt to capture with words – it’s because we’re not supposed to. Working to make is a space of total, immersing absorption where words cannot altogether exist because they somehow manage to clutter what we do. It’s why makers, when they are making and when they are done, say nothing that makes much sense. The small smile, a gentle sigh, the settling of the once stiff shoulders, the arms and hands that hang limp and dangled. These manifestations speak of many settled and peaceful things. I think that it is a space, a place, an occasion and an occupation where no words exist. Perhaps the art of working with your hands will one day be erased from most cultures, replaced by artificial intelligence in a way that nothing has replaced craft before. What AI will never replace is the soul of makers who work their material by the sensing of the substance they work. The spiritual element of handwork can never be experienced by or through any machine process because by its very nature, as with the lie, the machine stands in truth’s stead and the machine is designed to both displace and replace the need for feeling and touch by human senses and sensing. Because the machine was developed to replace both man and skill, our hands and arms may well lose the sensitivity craft demands and relies on. The machinist flexes almost nothing to make the cut but stands proudly by as the machine displaces the need of him and of her. Punching the keys delivers the intent and the machine adjusts to the smallest fractions of a millimeter, eliminating any human sensitivity. The whirring begins and the cutterhead passes into the wood. Minimal human energy is spent – no art is made. The end result is that the senses and sensitivity of man lie dormant and unused. And by this, I do not just mean the physical muscle and sinew. The belief in your own ability can be severely impaired too. Eventually, all becomes atrophied and dead, to be lost in any practical way, in the same way, evolutionary changes leave the back wings of beetles fixed and unusable. Accuracy then becomes more relied on as a programmable intent of unfelt energy. We no longer adjust for nor deliver precision by the human effort of planing and sawing, spokeshaving, chiseling as such. Instead, we tap keys that set distances and the mechanism turns the dials and sets the stops. It is nothing but soulless, yet when a human hand uses its energy it is measureless.

The joint lines should come together perfectly without clamping and additional pressures.

My hands have served me for 71 years to date. By serve, I mean they’ve manipulated hand tools and wood to make fine woodworking, furniture, and such on two continents equally and performed all of the other tasks of life. They still work and they are still good. One thing that I’ve come to know is that accuracy does not happen by accident. I am a fortunate man in that my hands have remained always sure and steady with no hand tremors, my eyes are still as good as when I was young and that my hearing, sense of touch, taste and smell seem to me unchanged. Defining exactly what accuracy is, almost defies the written word. Accuracy, in our world of making, marking, measuring, cutting and fitting, is as near as our imperfect humanity allows our hands and eyes to coordinate the placing of cut lines and our ability to cut true to such lines. In the theory of it, perfection disallows any level of what we often refer to as tolerance. Tolerance suggests marginalism. In the world of woodworking, indeed in any craftwork, it’s the intolerance of tolerance that sets the artisan apart from other makers. Creating perfect work from imperfect wood is to merely minimise any and all discrepancies. Our acceptance of margin must be so highly intolerant that the human eye and hand cannot detect any level of imperfection. Imperfection may well still exist, it just cannot be detected by human touch, sight, sound. There is no such thing as perfection as we might but are unlikely to know it.

It’s the knife that minimises need for tools like shoulder planes. My knifewall comes from a sharp knife followed by a sharp chisel. No compromise.

Once we realise the direct interplay of the three words I began with, we realise precisely that a positive codependency exists and our quality of workmanship maximises accordingly. I think this to be a marvelous development in our lives as makers.

38 thoughts on “Accuracy and Tolerance”

  1. Lovely post Paul. One thing I’ve struggled with as I started to learn hand tool woodworking is finding the balance between having high expectations of myself and what I can achieve with hand tools – gapless joints, clean shoulders in mortise and tenon joints, perfectly sharpened and set tools etc. I want to hold myself to this high standard in order to improve.

    However, on the other hand, I’ve needed to temper these expectations with the reality that, as I learn and attempt new things, I will make things that are decidedly imperfect. It’s finding the balance between maintaining these high standards (and in a sense, expecting every joint or piece to reach this standard), and cutting myself some slack when I don’t achieve it, which is key to enjoying the process.

    1. Vidar Fagerjord Harboe

      If possible, I’d suggest that when we make something using methods and / or techniques for the first time – perhaps consider the thing you are making a prototype or a test piece. If it turns out “perfect”, all is good. Any discrepancies above a certain level (let’s be honest, we tend to be overly critical to our own work – better adjust the level of acceptability than strive for absolute perfection), if not we can remake the piece if we want. Of course, this is not always feasible. Expensive wood or big projects would prohibit doing this.

      I recently made a small side table. The oak I used had some internal cracks that did not show until the plane revealed them. I also made a few errors here and there. Most of you would notice if you scrutinize the piece, but non-woodworkers won’t. And to be honest, it is rather well made!
      I am okay with the piece being as it is. Maybe I will remake the table with better wood, and perhaps give the first piece away or sell it at a very modest price. In the meantime, it stands in our living room. Maybe it still does in ten years time. I am fine with it either way.

      Even if I make ten more tables for sale.

      This way of thinking makes me feel good. I strive to do the best I can, but I accept that the pieces I make are placed at a certain set of coordinates on my learning curve. If I remake a piece after 5 years, I suspect the new piece would be better. But that side table will be here long after I’m gone. So will the errors I made. But they stand as witnesses that the piece was made by human hands, not a machine.

      1. Nice experience Vidar…
        perfection is something to strive for, attaining it is an illusion as well as a delusion. The fun is in the journey towards it…

      2. I think it can be summed up as “don’t let the perfect be the enemy of the good”.

        For Mother’s day for my wife I had already bought her gift, but wanted to give her a little something extra so made a knick-knack box similar to Paul’s in this article (since I stole the design from his videos). Took me closer to 4 hours instead of his 1, but I’m still developing.

        I of course knew every little flaw, of which I thought there were many. However my wife’s first comment was simply, “you’ve gotten really good at this stuff”. She didn’t notice the lid was turned about half a degree or the slight gap on one dovetail. And frankly I doubt I would if I wasn’t the one that made it. Even the tiny spot of tear out that I didn’t notice till finishing gives it a bit of character rather than detracts.

    2. As a new born in the woodworking hobby, i would like to thank you for this message.

      I’ve definetly chosen to be a handtoolist over using power machine, still i must admit that my first realisation miss the definition of perfection by quite a lot.

      I’m determined to become better try after try, even using as much as Paul’s techniques as i can, the result is highly improvable. just hope I’ll become better and better.

  2. An admin point about the blog: it appears to repeat the first paragraph toward the end of the blog post. Not sure if it’s easy to edit once uploaded and commented upon.

  3. A lovely post. I was intrigued by the sentence: “Perhaps the art of working with your hands will one day be erased from most cultures, replaced by artificial intelligence in a way that nothing has replaced craft before”. It got me thinking and wondering if there had been anything like it in the past. I don’t mean replacing metal working, or needlework or other hand craft, I mean the complete replacement of human senses or skills which you point out could be coming (if it hasn’t already arrived). I’d compare what we’ll likely see in AI to that of the introduction of agriculture (and most certainly modern farming). For tens of thousands of years, many humans subsisted on the abundance of our [rain-]forested planet, understanding smells, tastes, shapes (of plants), and touch of plants and insects, foraging playfully for meals, rarely constricted or hashed by time. As agriculture became more monotonous, more homogenous, those skills dissipated reducing the natural encyclopedia of plants in our minds to virtually nil today. The modern farmers in my circle of family and friends recognise only a few crops, have zero connection to their soil and see food through the lens of the plastic packaging in the supermarket. They’ve been completely removed from the food cycle in any recogniseable manner, simply following a series of seasonal instructions.
    It’s something I think we should be worried about. There is no fallback, no fail-safe built into this technological reliance.

    1. Vidar Fagerjord Harboe

      This year we made a kitchen garden where we grow taters, carrots, cauliflower, radishes, squash, tomatoes, chives, white onions and some berries. Next year I’ll try corn and possibly wheat or barley.
      The goal and motivation for me, is not only to try to grow different foods for the fun of it – I also want to teach my 3 and 5 year old daughters how to do it. When they become adults, they might not remember everything – but they will have the basic knowledge. I did not have to google anything to grow potatoes; I remembered the general steps from my childhood.

      It is the same thing with my woodworking. I want to teach my kids how to make things from wood, how to use tools and how to maintain them. As with growing food, I don’t know if they will ever use their knowledge – but they will know how!
      I think this is important to do to preserve such knowledge for the future.

      Oh, and buy your food from local farmers and REKO-rings! You won’t regret it. You might pay a little more, but you’ll eat high quality food! The producer gets all the money; you are not filling up the money bin for the big conglomerates who only cares about profit, not quality. The animated movie Wall-E comes to mind. If you haven’t seen it, I highly recommend it. The messages in that movie are food for thought!

  4. My handwork lesson: Measure twice, cut once is OK for carpenters. For joiners, it’s measure twice, cut it a little long (fat), and creep up on it. The quality and amount of creep necessary depends upon your intent, skill, and practice.

    1. My Dad was never a professional woodworker or joiner but when I was young and he was teaching me to saw he always said measure twice, cut once.
      Every time I make a mistake through not being thorough or even if I realise I’m about to make a mistake I say it to myself.
      I still use a saw horse he made when he was 15, well worn but still solid. He died last year at 91 so the saw horse is over 75 years old. I have passed on the mantra to my sons and will pass on the saw horse as well. It will outlive me.

  5. Thank you Paul for your thoughts.
    Just finished a little walnut side table made from wood from a tree in our yard that we had to cut down. If I may be so bold it came out beautiful and elegant (my dear wife’s words actually).
    And although I have spent years designing with computers including lots of 3D CAD, this table was drawn by hand, pencil and paper.
    My experience indicates that machine parts, structures, homes etc. all have become much more complex and harder to build. And more wasteful of materials and resources.
    And I blame a lot of that on the computers. CAD in particular. People are so focused on getting the computer to achieve the end goal that they build in a lot of complexity.
    Paper and pencil drawn designs seem to have a cleanness and elegance missing in CAD drawn designs. One only needs to look at the crazy roof lines on houses now.
    So your thoughts on lack of tolerance for lack of sensitivity and precision resonate very much with my lack of tolerance for the overly complex designs and drawings so prevalent today.
    Keep it up sir! We appreciate reading your thoughts. A man with your experience deserves to be listened to.
    tx, Ed McGugan

  6. Thanks Paul. I can attest to how quickly one learns the skill (and then spends a lifetime refining those skills). At best, I was woodworking in my shop 200 hours a year on weekends. After about two and half years, I was starting to tackle more ambitious projects. They came out pretty good. Certainly there were flaws but not so bad it wasn’t useable and mostly only I would notice them. Two and half years is about 600 hours of work or as if I had taken a 14 week immersion course.

    Even with 2020/21 and much sheltering in place and 5 and half years of woodworking, I doubt I have even 2000 hours of bench time, At this point, I feel confident to try and make anything I want. That is at best as if I have done a one year apprenticeship. Sure, it won’t be perfect but it will be pretty good.

    What really helped me recently feel better about my work was a visit to a consignment shop near where I live that sells hand made (well machine made actually) furniture. Certainly it is nice but my stuff isn’t that far behind in terms of quality.

  7. This post strikes me differently than others you have written. Usually I feel inspired to try something new or build a new skill. After reading this one, I feel the need to sharpen my tools. I feel the need to practice, practice, and practice some more. I feel more keenly aware of my short comings as a woodworker. I don’t say this is a negative context. I mean that I know what my opportunities are to improve. I’m looking forward to it! Maybe, still inspired. Just inspired in a different way. Thank you again for taking time to deepen our understanding of this craft!

  8. Paul, I appreciate the humility by which you describe your work. It is refreshing to see someone comment about their skill, yet allows the work itself to provide the commentary.
    While my “retired” life is as many have said, busier than ever, it is a rare day when I don’t at least get to the woodshop even told it is to sit and smell the smells.
    It is a good life.

    1. I think every woodworker (artisan, maker, beginner, or otherwise) should occasionally do themselves the service of entering the shop without doing any work at all – not even a single layout line. Just exist within your shop and experience ITS existence. Even if for only 5 minutes, acknowledge your shop for what it is: the smells, the colors, the atmosphere, the textures. We work our wood but, our wood, more often, tends to work us.

      Isn’t it really such a beautiful thing?

      1. Vidar Fagerjord Harboe

        I go out into my shop almost every day just to get a few minutes to myself. I almost always have something to do there. Sweeping. A quick sharpen of a chisel. Doing a bit of plane work on parts of a project. Nothing much, just a couple of minutes at the bench, the sharpening stones or tidying up a bit.
        Or just letting my hand glide over a piece of oak to feel the grain.

        It’s therapeutic!

  9. I have been a hobby woodworker for better than 40yrs now. I own a production Delta tablesaw and a host of other machines. I soon realized that while I had a stable of decent machinery there were a lot of tasks they would NOT do. So I still have to resort to hand tools to finish the job. What I learned along the way is that there are specific small techniques that make both learning hand tools and using them much more enjoyable. THAT is what leaves a smile on my face. When I have learned to sharpen my planes and chisels and then how to use them. There is a certain satisfaction that comes from all of this finally coming together that makes the other learning curves much more enjoyable.

  10. While finishing a wood working project is something hopefully to be admired it not about the work but rather the journey to enjoy!

  11. This article made me think of a quote I read by Mahatma Gandhi and it is inspiration for me as a wood worker:

    “It is a tragedy of the first magnitude that millions of people have ceased to use their hands as hands. Nature has bestowed upon us this great gift which is our hands. If the craze for machinery method continues, it is highly likely that a time will come when we shall be so incapacitated and weak that we shall begin to curse ourselves for having forgotten the use of the living machines given to us by God.” Mahatma Gandhi

  12. In 2017 I didn’t know what a bench plane was, then discovered Master Sellers.
    Now, I am making an ambitious station for both tool display and storage, a marriage of form following functions, that is accurate and beautiful.
    I got all the skills I needed from watching Paul’s bookshelf build, then following it scrupulously, building a small one and a large one. They were my first projects, and they came out quite well.
    So what I am saying is yes you can achieve remarkable results as a beginner; there is no mystery to it, only attention and care, and making sure you understand your tools and how to keep them sharp. Those videos are complete, and will teach you almost everything you need to know about joinery. Hand tools only, for me.

  13. Great stuff Paul! Thanks for taking the time to create this newsletter for us. The topic is so appropriate for me. Over the years I have had to let go of perfection without sacrificing accuracy. I love the challenge of creating something using hand tools working within tolerances that tool and die makers might work in. As a former machinist I know what it’s like to work with very close tolerances (0.00005″). I can’t achieve that with wood working. But I still approach each project with that mindset. If I don’t accomplish such tolerances so be it. But at least I can say that my goal is/was to work as accurately as I can.

  14. One of my favourite posts from you, Paul. The entire thing, but especially this:
    “Instead of pushing the boundaries, they are willing to be constrained by them. They don’t throw off the restraints handwork demands but pull them on.”
    Just brilliant.

  15. Scott Swineford

    Well said Paul. I very rarely make multiples anymore. A few things I’ve made for friends of my family members that they asked me to make for others. Even those are either design improvements or have details for a particular person. Recently I made a bunch of things for my daughter’s crochet group of friends and though I cut the primary parts in a batch it was stacked pieces cut by my old disston at a time. A couple layout jigs for joins and hole locations and an indeterminate amount of coffee.

  16. This is one of my favourite posts. As a relatively inexperienced woodworker, I find myself spending a lot of precious time trying to figure out how to use my trim router safely and accurately. Recently, while making a series of small boxes for friends and family, I’ve chosen to use the router for doing simple rabbets, nothing else. Everything else is done with handplanes, chisels and backsaws. It’s quiet, satisfying work that rewards patience and concentration. Having done five different boxes this way, my skills are developing. Having Working Wood as a handy reference has been invaluable. Knife walls and shooting boards are my new best friends.
    Best wishes from Toronto.

  17. Planing adjacent surfaces at the 45 degree corner joint in picture frames proved to be a challenge for me. If one side of the 45 degree joint is high do you register the plane’s toe on the high side and finesse the iron into the step you want to remove?

    I found that I could get one face smooth but the other would have minor tearout or other defects from planing. Perhaps my level of sharpness could be better. Lot to figure out!

  18. “Accuracy is a prerequisite, not an optional extra.” It’s a phrase I wrote many years ago and it hangs over my workbench. At 70 years old having served my apprenticeship and worked as a marine engine fitter, having worked in marine engineering and for over forty years working with wood, as well as many years in stone letter carving, I have come to the conclusion that some are inherently accurate, they seem to be unable and definitely unwilling to be inaccurate. For others, accuracy is not inherent and has to be constantly worked at. As an apprentice I was taught by an old bench fitter that “engineering is the science of exactitude. ” It applies to every discipline. Whilst I totally agree with what Paul says, (and does), I do marvel at the breathtaking accuracy of machinery, made, operated and maintained by men with hands, that can reproduce micro and macro components many millions of times to within tenths of a thousandth of an inch and even more accurate than that. It’s that kind of machine accuracy that guarantees every time I pick a packet of biscuits or a cake up at a particular supermarket, it always tastes the same as it’s predecessor and when I dismantle electronic equipment, I see microscopic accuracy. Accuracy really is a treasure and a pleasure

  19. First our hands relinquished from true purpose, then our minds. We mustn’t forget our organic and simple nature despite the complexities of a world that sells us ‘the easy way’. Nothing could be more inaccurate!
    Great post Paul.

  20. I am enjoying my journey into hand tool work. I was out last night chopping a a couple of mortices for a bottom rail in a door I am making to replace my crawl space door. I could have made it out of a sheet of plywood but I wanted to challenge myself and learn. I had gone about as far in as I thought was possible and decided to shorten my tenons. I woke up at 4:30 AM and thought, that was stupid, Paul would have had me drill out the waste to make it deeper and I have just screwed up. You have a funny way of teaching at times. Keep up the good work. Now on to ponder the best fix if one is needed.

      1. Paul, before i scrolled down to your comment I knew what you would say. I must be reading your words too much.

  21. Paul, I commend you on a wonderful way of thinking. Yes, this is a beautiful journey, and I get to share it with my grandkids, who are more interested than their parents. I am slowly teaching them, slowly because they won’t want to accept it if it’s shoved down their throats.

    I am one who used power tools, almost exclusively. Due to balance issues, which I won’t get into here, I was told I’d have to give up woodworking. My response, I would give up power tools, but would learn hand tool woodworking and practice that instead.

    What I have discovered is a peace of mind I never believed existed, one not available through using power tools. Aside from this, I’ve not compromised perfection, but have realized, and persistently strived toward always improving what I do. I’ll not tell people the shortcomings only I notice. They won’t see them if I don’t point them out. I see each piece of furniture, each box, etc, as evidence of my journey, always improving my execution of skills.

    For a while, the pain is gone, and I concentrate only on the item on which I’m working. For this I thank you. I will continually strive to get my grandkids, and possibly their parents through them, interested in doing things in a more peaceful way.

    1. I think some things do skip a generation and that includes an interest in crafts. I made certain that my boys all partook of crafts for enough years to establish skillfulness in many areas and before they were adversely influenced elsewhere. That meant that their abilities were established before they were 18 years old and what they learned equipped them for life. I certainly did not want anything to steer them away from being competent in using their hands so they did blacksmithing, woodworking, pottery, leatherwork and more over a number of years.

  22. Paul what would you suggest as a good jointer plane for someone who understands the process fairly well but kind of struggles with non electric hand planes.

    1. The largest plane I ever use is a jack plane so I don’t recommend longer planes because there is so much metal they never stay straight as they are always radically affected by temperature changes. I use both the 5 and 5 1/2 types. But that doesn’t mean long planes aren’t any good, if your temperatures in your workshop are reasonably constant you shouldn’t have a problem. I have just got used to flexing both my plane and my attitude in using them as I use them. You can bend planes quite easily albeit by a minute amount, via the handles of the plane. Many do this without even realising this happens. It can easily be proved that this takes place in normal use. That being so, I can create a long and gradual hollow or a long and gradual round with a longer plane.

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