How NOT to Turn a Bowl
and the Aftermath
by Roger Dunn
Here is how I got my mask (enclosed photos taken 48 hours later) ready for Halloween.
I enjoy turning large bowls. In October I roughed out a blank of Horse Chestnut 15 inches diameter by 8 inches tall and left the walls 1 1/2 inches thick. I noticed a thin bark inclusion running through the blank almost on dead center, up one side, through the tendon for my chuck and up the other side. It appeared the same width inside and outside.
I soaked the inclusion with thin CA glue several times and was careful not to use accelerator. Then I soaked the blank in alcohol overnight, wrapped them per Dave Smith's recommendations, and let them dry three weeks. When I remounted the blank I was amazed that it ran nearly true. Since there was almost no wobble, I didn't bring up the tailstock. My tendon was 3/4 inch deep and 4 1/2 inches wide. I was using a Nova 5" chuck. The chuck was opened to the maximum and had a good bite. I put on a face shield and dust mask under it because the wood had grown a crop of penicillin in storage.
I took light shearing cuts (fingernail grind bowl gouge) on the outside to clean up the surface. My lathe was at 300 rpm. When I got through I noticed I still had a small amount of tear out. So I reached through the "throw zone" to turn the speed control up to 400 mph. As I was straightening up, I got whacked "upside the head". I went down to both knees but didn't lose consciousness. I got the lathe turned off and noticed my head felt bigger than I remember so putting my left hand to my left temple I felt 1/2 of a softball on my head and went inside to a mirror to assess the damage.
I drove myself to Group Death in Silverdale and an ambulance took me to Harrison for a CT scan. Luckily, it was a glancing blow and the shattering face shield absorbed enough of the impact that I wasn't made into a carrot or a corpse. No skull fracture, no concussion, no loss of consciousness, no vomiting, and only a small loss of blood from the 'road rash' kind of wound.
The photos were taken 48 hours later. They don't show my softball sized knot as big as it was. The bruising and settling of the blood closed my eye for two days, my face, and neck took on the look of post mortem lividity. Unless you want to have a mask like this, here are some of the things I did wrong due to impatience, cockiness and stupidity. Please learn from my foolishness.
- The bark inclusion separated neatly because the CA that I thought had saturated it and made it as sound as new, had only seeped in about 1/4 inch both inside and outside.
- The denatured alcohol soak may have weakened the bond but I've used CA glue blocks and soaked in denatured alcohol for a year without any joint failures so I tend to discount this as a major goof. I cut away a lot of the CA glue joint when I was truing up the outside, thereby weakening the joint. It is kinda' like sitting on the limb you are sawing off.
- I didn't have the tailstock in place inside the bowl for safety. The tenon for my chuck should have been longer and narrower, where there could have been more surface to grab.
- I shouldn't have reached into the "throw zone" with the piece spinning and turn up the speed.
- The acetate face shield was too light. I've replaced it with a polycarbonate one but even that isn't sufficient to stop a dismounting blank if to get smacked in the center or square into the side of your face.
- I shouldn't have been turning something that big with a bark inclusion running all the way through it. I disregarded Dave Schweitzer's admonishment to never turn large pieces of unstable wood.
- The speed was too high.
- I was in a hurry to get another bowl ready for a craft show the following week.
With a chagrinned look that has taken on a peculiar greenish, yellow pallor,
Roger Dunn
© 2005 Roger Dunn, All Rights Reserved