At the dawn of time, when man first picked up a piece of wood and thought what can I make with this? His answer almost certainly was, not much, because I’m never going to produce a decent cross-grain housing or dado with these bits of flint and threw the wood on the fire in disgust. This sad situation continued until the introduction of the skewed dado plane which may well have been in the mid eighteenth century, quite a wait and a quite a lot of fires.
With more a slightly self-conscious look-at-us-we’re-spoilt-for-choice-now glance towards our ancestors than to actually make something, I dug out some wooden dado planes from the tool cupboard. One criticism levelled at them concerns their natural desire to warp, back in the days of wooden tennis bats we used to use a kind of spring loaded clamp to stop their own twisted tendencies, maybe something similar could be used or even those old Rickets splints if you haven‘t thrown them out.
These planes come in various widths and really do work quite well once they’re adjusted correctly and sharp and straight, you’ll notice the metal spurs sometimes called slitters or snickers or even nickers.
Which conveniently reminds me of a tall, sylphish goddess named Sonja, could have been Sonya but not Sandra. I suppose the elastic gave way and they just slid to her ankles, we were walking along a long corridor at work. In one fluid movement, she stooped, removed them and tucked them in her pocket, hardly breaking stride, smiled and continued walking. She was so cool and as graceful as a ballerina, a wonderful person who I admired big time, obviously not just for her ability to disrobe on the move.
If it had been me and I don’t know how it could have been, but if it had been I would have spent five minutes wriggling around on my back like an upturned tortoise pulling helplessly at my underwear firmly knotted round my shoes as my pants gradually stretched like chewing gum to the length of my leg. Probably muttering “sod it” over and over again, as a circle of colleagues formed around me offering advice and encouragement, “no, no, no look they’re still caught on your heel, pull upwards then to the left, no, no, your left.”
The spurs don’t need to gouge to any great depth, more just scratch the surface as I‘m doing here. I’m not an authority on any of this so if you want to set them to cut deeply that’s absolutely okay, but they really just need to slice the wood fibres a fraction deeper than the depth of cut of the blade, cutter or iron. From here on in, I’m going to call it a blade. So adjusting the cutter, usual procedure, step 1- remove cutter and wedge, step 2- replace cutter just less than desired depth, replace wedge and tap gently, step 4-try to plane some wood, step5, repeat steps 1 to 5. Until you are satisfied or have grown too old to remember or even care what you are doing holding this plane in one hand and a small hammer in the other and you keep looking from one to other whilst slowly shaking your head. The shed door opens throwing a shaft of sunlight on your bemused, tear stained and wrinkled face, you look up squinting against the glare to make out an elderly woman you vaguely recognise from years ago holding a cup of tea and with a faltering, barely audible voice you ask, “is it all over? Can I use it now…can I? “ It’s actually not too bad after a bit of practise.
Just how important is it to be skewed? Well, that’s a big question, but in the present context for all sorts of technical reasons it really is helpful for cutting trans-grain. The somewhat esoteric technicalities mean in effect the pitch of the blade is lowered without changing the actual pitch. Picture yourself walking carefree and laughing up a hill in a zig-zag or series of inclined planes as opposed to struggling wretchedly in a straight line. The thing you should constantly bear in mind is the sine of the physical pitch and the cosine of the skew angle will give you the sine of the effective pitch.
I suppose the ancient plane makers arrived at the perfect angle of skew empirically, you may ask do they vary between makers? I don’t believe they do, perhaps it was the blade makers who dictated the angle and the plane-maker had to conform or be derided and ostracised when they all met down the pie shop at lunchtime. “How’s that thirty-seven degree skew Isaac hahaha?”
“Yeah, yeah, very funny, careful you don’t split your cod-piece Moseley, you git.”
We will need a straight edge to guide us, no need to kneel in the desert looking upwards, as any firmly clamped small piece of scrap wood will do, set the depth stop, draw the plane towards you a couple of times so the spurs start to do their thing and that’s it, plane away until your depth stop stops you.
If you are by nature a person who eschews safety and is prepared to live on the edge no matter what the consequences, and says things such as, “I’m like Hemmingway man, watch me”, you can remove the guide after a few passes and the cut is started. Are you are overly fond of porridge and cold weather? If yes, then none of this will make any sense until you substitute the word raglet for every time you see dado, some viewers may trenchantly disagree with the word dado and raglet. I have also always refused point blank the optional e in ‘dados‘. If offered, just say no.
Welcome, I am Nactus Stimp.
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