Lay down Sally! Or the dust goes boom..

Put the plane down on its side, or you’ll risk damaging the edge! Or so it is often taught. Don’t you dare to question ye olde wisdom!
Also, dust collector systems can blow up. Apparently.
It’s mythbusting time!

This is a "rant" - an article where I give my opinions on things. Usually, the rants are triggered by something I read or see online. In the rants, I do not try too hard to be unbiased although I try to be accurate and do think things through. I lean on other opinions as well, from well established folks that has proven themselves. At the front of that line, you'll find Paul Sellers and Richard Maguire (the English woodworker). Read this article as it is intended - informative, provokative and with a large amount of humor. Then draw your own conclusions.

I’ve seen it too many times. Woodworking myths and misconceptions perpetuated by people who means well, but don’t know what they are talking about. Such as “lay the plane on its side, or you risk damaging the edge”. Hogwash! If placing the plane sole down causes your plane iron do ding or dull, you should probably clean up and tidy up. The only way you can cause damage putting your plane(s) sole down, is if you put them on a chisel or some other stuff that is hard enough to do the deed.


Now, by stating this I do presume your work bench is a wooden one. If you do woodwork on anything else than a wooden work bench, you should reconsider. A wooden surface, with an oil finish, provides friction. Friction is good. Helps with work holding and stops things from sliding around too much.

I came across one of these comments, and it was like driving by an accident without slowing down and look. I could not resist. I pointed out that this was wrong, and this is the reply I got:

not a myth. I’m a former woodworking teacher with an advanced degree in Industrial Technology. When a cutting blade is sharpened properly, the final sharpening on the cutting side leaves a small curl toward the opposite side. This is straightened out by stropping the other side with a fine stone or leather strap. This final edge is microns thick and is what gives the long curling strips of wood which are a source of satisfaction using a hand plane. When you set the plane blade down on your work surface (I never said workbench) you bend this micron thick edge thus dulling your blade. This is why you should start your cut with the toe on the wood and the blade off the wood pushing smoothly until the blade leaves the wood before picking it up.

-a plane sidelayer

This was a trifecta of wrong or irrelevant claims. First: lay the plane on it side. See paragraph one.

How is this practical??? I get cuts just lookin’ at it!

Second: the notion that this “microns thick” final edge somehow will be bent upwards by the weight of the plane, but will suffer little ill effect as soon as it makes contact with the wood. Won’t it be bent backwards? What if I got a bevel up plane in stead – would that fix the problem? I mean, since the geometry in effect is like a bevel down plane iron where the bevel backs up the edge like when a bevel down plane is planing. It should not matter which side of the bevel is sharp. If you’re picking up what I’m puttin’ down.

Third: starting a cut with the blade outside the wood. You don’t do that unless the piece is shorter than a plane stroke. If you are planing a 2 metre (about 6.5 feet) board, you start at the left end and work your way backwards (being right handed, of course – no lefty work here :-P).

In the image above: my patented edge retention device MKIII.
The manual states that it works even better if the plane iron is removed.

Mr. Sidelayer did eventually agree that the bending of this micron thick “final edge” really was not very essential: “the lost of the micron thick cutting edge makes little difference but that doesn’t mean it’s not happening on some level“. Mr. Sidelayer, who told me to call him Dr. Sidelayer if I wanted to be formal (since he was a doctor in something or other, I don’t know what or the relevance of the title), clearly did not want to concede. I provided references and “peer reviewed” content – or a good substitute for peer review; Paul Sellers has a very strong online presence, and he has not been proven wrong. Which if it happened, would create quite some turbulence. I regard that as a decent substitute for forma peer review.

Paul Sellers has a very good article about this topic, where he says ” I never saw any of the men who trained me lay their planes on their sides, only insistent school teachers.”

Behind the scenes. Thor props up the planes.

I think this is the perfect place for me to put a QED. “Only insistent school teachers”. When I attended the university, we were told that QED should NOT be used unless what we claimed was proven, was indeed correct. Putting “QED” on a paper that was wrong, was considered worse than the same erroneous paper without those three letters. I used them once, and my answer ended up in the solution proposals. Guess I indeed used QED correctly.

I’ll round off this part with Mr. Sidelayer’s final words to the comment: “it’s under less pressure sitting on the bench than it would while working with it plus it protects the blade from getting chipped.” To which our resident doctor replied:

actually when working the blade forces are linear to the edge…when sitting on the blade the force is tangential to the cutting edge and tends to bend it up

-Dr. Sidelayer

Which in and of it self is absolutely true, but as relevant as determining the drag coefficient on the tassels on flying carpets. There are other elements in play that affect that edge vastly more.

Oh, well – you can’t win them all.

Dust explosion – do you know what’s lurking in your shop?

…and the dangers of PVC pipe which you cannot possibly ground!

No photoshop used! (…I used Gimp.)

EVERY single time someone ask if PVC drainage / plumbing pipes can be used for a dust collection system, without fail someone will warn about the dangers of dust explosion due to buildup of static electricity which may create a spark that ignites the airborne dust. I’ve even seen someone claiming that the static electricity will eventually build up enough so that the dust settles like sand dunes in the pipes.

Where do they get this type of “information” from? Even after ten years of Mythbusters, people still believes in such nonsense. Of course, I am assuming that eeeveryone has seen Mythbusters. Because they should!

Anyway, back to the dust explosion thing. It has never ever happened in a hobby shop. No records of any occurrences exist. It has never happened. Besides, you remedy the problem by wrapping a piece of copper wire around the PVC pipe which you then ground. Problem gone. Which problem? The fact that static electricity WILL build up on the surface of a PVC pipe with lots of dry dust wooshing through it – if certain conditions are met. As soon as you touch the pipe, you’ll get a blue reminder that thousands of volts are painful.

Just think about it – central vacuum systems uses PVC pipe. At least here in Norway it is common. We have that in our house. No explosion reported or experienced so far. Not even static buildup, and we have a long haired cat named Molly…

But – you cannot ground PVC pipe! John McGrath made a real nice clickbait video on the topic. Technically he is right in his claims, but oh does he fail on the conclusion. And the premises for that matter.

Dust collector ducts – or cannon barrels?

The thing is – with a copper wire wrapped around the non-groundable PVC pipe (no issues there, PVC is a very good insulator), the static electricity is dissipated enough so that it won’t build up to levels exceeding the breakdown voltage of air (which in fact is not a real thing nor a given value, but this is a woodworking blog and not a physics blog. I’ll leave the googling to you). In the video, he spends a few seconds rubbin’ the end of the pipe without wire to charge it until it can pick up a few small pieces of paper. He does the same thing on the end with the copper wire wrapped around it – but here is the problem: He rubs the pipe for a very long time, and he has to get really close to the paper pieces before they stick – and it takes some time. Which to me proves my point: the copper wire dissipates the buildup so that it won’t be as strong. Aside from that, he clearly does not know how to conduct an experiment in a manner which can be used to form a conclusion – or at least he does not do that in the video. Don’t get me wrong – it is a great video, it is just that it does not provide proof to his claims.

In short (!) – wrapping a copper wire on the outside of your PVC ducting (and of course run it to electrical ground) ensures that, in descending order of botherability and concern:

  • You won’t get zapped. Which is the only reason why you would do it.
  • The ducts will gather slightly less dust
  • The ducts will increase in value (copper is valuable)
  • Something about planet alignment
  • The chances for a dust explosion is greatly reduced. From near nil to even closer to nil – asymptotically.

To conclude the topic of grounding PVC ducting: If you have a problem where your PVC dust collection grid zaps you because it becomes loaded with static electricity, wrap a copper wire around it which you run to ground. Problem goes bye-bye. No zap, no wrap.

This is in line with the experiences from several people that did this to their PVC dust collection duct systems. I have seen the comment several times on Facebook and in a few forums. I cannot for the life of me find them again just no, so no links.

You might think this is to joke about a hazard, but it’s not. This topic has come up a lot, and over the 15+ years I’ve been active on woodwork forums, facebook, Youtube and so on – NOBODY has given ANY account of this actually happening. EVER!

If a dust collector system blew up, we would know about it. Trust. Me.

The Wood Whisperer, Stumpy Nubs, WWFMM (too much to type), Matt Estlea, Matthew Cremona and just about every single Facebook group remotely connected to woodworking, would go completely, utterly, totally, leftright, unconditionally, outright, rightright and downright bat s**t crazy over it. John would blow a fuse. As would I.

It has not, almost guaranteed never will and highly probably cannot happen*.

*Liability clause, because if an unlimited number of woodnumbnuts sand an unlimited number of end grain cutting boards, one dust collection system will blow up. Mathematically speaking.

Grain bins are a completely different beast, and they blow up regularly it seems. But the stoichiometric factors is a bit different there. Dumbed down: you can’t produce enough dust, finer enough, in a short enough time and get it mixed correctly with air to be a problem. No boom for you!!!

In theory: yes, you can make that much dust that fast. But that is like sharing a donut with 359 other people. Mathematically, you cut the donut into 1° slices and serve. Not even the best Japanese toilet paper producing plane can pull that one off.
Theory 0, real life 1.

By the way, the shavings you take with those going against the grain is great for a low-fibre diet. Just sayin’..

As for physics, I’ll leave the topic with this fact: A plane will take off if it is placed on a conveyor belt that matches the plane’s speed, but in the opposite direction. I.e. if the plane goes to the left at 20 mph, the conveyor belt spins to the right / clockwise at 20 mph. Aaaaaand kumite!

By the way: Mythbusters did an episode where they sandblasted a PVC pipe – the “static cannon myth”. They found that the static buildup dissipated through the jack stands and into the ground. The stands were placed about 8′ (about 240cm) apart. I rest my case. On metal jack stands.


Hand planes can safely be placed sole down. This is the best practice since we remove an exposed, sharp edge and the plane will be optimally placed for retrieval. Just grab and go. This is of course provided that you work on a normal, wooden surface without a handful of nails scattered about. DO NOT perpetuate the myth any more, even if you still choose to place your planes on their side. That is your choice and it’s fine – but it has nothing to do with damaging the edge nor the dulling of it.

A PVC pipe based dust collector system will not blow up due to static electricity. Wrapping the PVC pipe with a metal wire (copper is excellent) connected to ground will dissipate the buildup of static electricity so that you won’t get zapped badly, but that’s it. You can’t ground PVC pipe, so there will be some buildup of static electricity.

You SHOULD however be concerned about tiny metal filings or pieces entering your dust collection system, where it may create a spark which can start a smoldering fire.

Dang it, Steve! I told you to buy Festool!!!

You know what? Combine the info in this article and start using smoothing planes in stead of sanders! It is faster, less noisy, gives you a bit of a workout and produces shavings which is great for starting a bonfire.

It is plane simple!

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