Tag Archives: shop safety

What I Screwed Up Back Then – Carving Injury

It’s Shop Safety Week again, when we focus on a subject that should be near and dear to our hearts all the time.  Nevertheless, a few timely reminders are never out of place.  This cautionary tale, drawn from my own experience, shows how even a small shop-related injury can have a big impact.

The Problem:

Some years back, I was making a small carving of a mule in ponderosa pine.  By small, I mean about 3″ long – small enough to be held comfortably in the non-tool hand (experienced carvers, don’t spoil the drama for everyone else).  I was working slowly, cutting with a standard drop-point carving knife with a 1 1/2″ blade that I had just stropped.  I had the knife under (I thought) good control, using opposing pressure from the thumb to keep it from flying off into space as I refined one of the mule’s legs.

Carving Injury 1

Suddenly, the soft pine leg snapped, allowing the freshly-stropped knife point to plunge downward and into my hand.  The photo above shows the approximate hand positions and arc of the blade.  (The hound dog graciously agreed to stand in for the mule, and was not harmed in the filming of this article.)  There was no pain and little blood – the cut wasn’t that deep.  However, I immediately knew something was wrong – my fingers weren’t moving right.

Carving Injury 3

Suspecting what was wrong, I was careful with the hand until I could see a plastic surgeon the next day.  This, by the way, was the same plastic surgeon that fixed my previous screw-up. My fears were confirmed – I had severed two tendons in my palm.  This required surgery, and eight weeks in a brace that held my hand flexed inwards at a 90 degree angle.  Even after healing and physical therapy, the hand has some issues.  For example, as you can see above, extending three fingers doesn’t go quite as it should.

The Solution:

Hands are fragile.  There are a lot of operating parts crammed into a small amount of space.  Grip the palm of one hand between the thumb and fingers of the other and wiggle its fingers.  Feel all that movement?  Those are the tendons that control your fingers, right below the surface of the skin.  It doesn’t take a lot for a sharp tool to go through the skin and effortlessly slice one or two.  Even if you don’t cut something off, the long-term effects can be life-altering.

The solution is deceptively simple:  Always wear a cut-resistant glove whenever the situation requires that you hold the item being carved in your hand.  I say “deceptively” because “cut-resistant” covers a lot of very confusing ground.  Products range from simple woven fabric “cut gloves” all the way up to chain mail, with proportional ranges in price.  While mail probably offers the best protection, I have worn mail gloves in the past, and the weight and discomfort disqualify them for me.  Kevlar is popular but, while bulletproof, isn’t overly resistant to puncture.

National Safety Inc. has a pamphlet that will help you make sense of the different types of glove materials, so that you can make your own informed decision about the level of protection you need.  It’s a bit technical, but has a good chart on fabric types.

Carving Injury 2

For me, the choice was a glove made of a fiber-stainless steel blend fabric.  True, it’s a bit stiff and scratchy, but the cut-resistance is outstanding, while not being too heavy or restrictive.

Whatever your choice, the important thing is to chose something.  ANY time you’re forced to perform an operation where your hand might have to be in front of a blade, hand protection is a MUST.

Learn from my mistake, rather than making your own.

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What I Screwed Up This Week – November 28, 2010

Well, I hope everyone in the States had a very happy Thanksgiving.  As usual, I ate too much and had to work the weekend.  However, I still managed to get in some shop time.  That, of course, leads us to this edition of What I Screwed Up This Week.  This one actually happened a few days ago, but I just now worked it in to the lineup.  It actually relates to stock preparation that I did for the frame of the Wing Chun dummy.

The Problem:

As I was ripping 2×10 stock into 4” widths for the frame components, reaction wood caused one of the 8’ pieces to bow inwards.  This is always a prime cause of kickback, but fortunately, my SawStop has a very good riving knife, so I was in no immediate danger.

The Solution:

Wing Chun Dummy - Prepping the Stand Stock 1Interestingly, the piece was only bowing on the left-hand side, away from the fence.  The fence-side part of the wood remained perfectly straight.  Such things can occur as a result of varying stresses on different sides of the log caused by unequal growth.  Due to the fact that I still had a solid fence reference, I decided to continue with the cut, but remained well out of the way.  The cut went just fine until the last inch, when the built-up stress of the curving piece pressing against the far end straight piece caused the two parts to separate rather violently, sending the left-hand piece almost a foot across the table.  You can see the result in the photo to the left.

Lesson Learned:

Always be alert for reaction wood.  A piece such as the one above that spans the pith of the tree is a prime candidate for this.  If you notice bowing in a piece as you cut, stop immediately and asses the situation.  If you don’t have a riving knife, DO NOT CONTINUE THE CUT.  Even if you have one, don’t continue if the wood is warping away from the fence.  In retrospect, I underestimated the force of the bowing action of the wood, and had an unexpected occurrence at the end.  I probably should not have continued the cut either.  Remember that if wood shows signs of movement, it’s not going to stop until the energy is expended.  Also, never forget that tablesaws don’t have a very forgiving nature.  When in doubt, shut it down.