Apprenticeship Day 22
Wood. What a wonderful material to work with. Twists in the grain, hidden knots, bark inclusions, and the hot topic of the day - funky punky heartwood. Still, the stuff does grow on trees. Well, in them.
So we lost a couple more bowls to checking. The really dark heartwood, closest to the centre, cracked. Jarrod voiced his doubts about that material from the very beginning. We had a whole series of bowls with a similar looking heartwood dry without issue. This tree is a little different. Some of the bowls survived, but they had a minimal amount of that wood in them. So we're just going to have to be diligent in our removal of that part.
Zoom and enhance!
Which was an issue with the first blank I started on today. I grabbed it from the pile, axed off the corners and mounted it on the lathe. Yesterday Jarrod suggested I work a little harder at making sure the mandrel is spinning completely level. A couple of my bowls were spinning with a bit of a wobble. Within tolerance, but still something to improve.
So I took my time making sure the bowl was mounted right. Slowly rotating the bowl shows where the high and low spots of the wobble are. Rotate it to the lowest point then remount it with the mandrel below the spot it's currently in. It usually takes me several attempts. I find it helps to pick something behind the mandrel to focus on, how much the mandrel obscures that distant object shows how much off centre it is.
So I got this blank as close to perfect as I could. Happy days. Imagine my disappointment when, after a bit of rough shaping, the damn thing had developed a wobble. Somehow the mandrel had widened its hole into an oblong. Either I didn't smack it in hard enough, or during a particularly deep cut it might have jumped out of the hole and drilled a new one that joined up with the original. However it happened, it had to be fixed. So off the lathe and to the chopping block. I axed away the mandrel hole. I then realised that I hadn't axed down the top surface of the bowl to remove the funky punky wood. So that happened. Which revealed a knot, near the rim of the bowl. Sigh. Rather than monkey around with it further, I set it aside until I could get Jarrod's opinion on whether it was worth the effort.
Fortunately the next blank went much smoother. I managed to rough out three bowls in total, making sure none of that heartwood was in there. Jarrod had a bit of a tougher time of it today. He put up some new shelving in the workshop, opposite where the current drying shelves are. Those shelves are under some heating pipes. Hopefully moving away from them will help reduce cracking. It's not a great feel to have spent hours on something, only to have it fall apart. I think it was especially frustrating for him as he had his doubts about that heartwood from the beginning.
To make matters worse, one of the bowls he was turning sprouted a crack while on the lathe, and a goblet, which was almost finished, developed a kinked mandrel that kept getting worse and worse, eventually ruining the piece.
Like I said; wood, what a wonderful material to work with.