New turner seeking advice

[Jason Slutsky]

I'm proud to say that I just recently became an addict and do not plan a recovery any time soon.

One of my early projects was to turn a bowl out of a blank of tulipwood that I bought at a local store in upstate NY. I was told that these blanks should be treated as dry wood and not green. As I was turning, the wood did not seem wet at all but a week after I finished it, a very small crack developed in the base.

Was the wood that I felt (and was told) was dry possibly not? I'm guessing that experience will allow me to better judge dryness of wood.

Also, I have so far done most of my learning using Keith Rowley's book Woodturning - A Foundation Course. In this it says that when turning bowls to turn with the heartside at the top because any shrinkage will result in hollowing of the base which will not affect stability. I did this with the tulipwood bowl and the opposite (however so slightly) seems to have occurred. Can anyone explain this to me?

I now know that these supposed "dry" blanks are not all dry because I also bought a tasmanian burl blank that I plan to use for a goblet. While I roughed it down last night, there was definately moisture on the gouge. No doubt about the lack of "dryness" in this one.

I've read plenty about turning green bowls and the fact that you must dry them after roughing them out but what about other objects? Is the same precaution necessary?

Thank you in advance for your help!

Jason

[Ken Fitzgerald]

Jason...First .....Welcome to the Creek! Welcome to the Abyss! I've been turning about a year and am a Spin Crack Addict too! Sorry about your bowl cracking....it's possible that it wasn't dry...it's also possible that by turning it you allowed it to release some stress that was there. It's hard to say....most likely it wasn't completely dry....but you'll find that isn't too unusual!

I'm sure some of the more experience turners will jump in and give some good advice...I'm a relative newby myself!

[Neal Addy]

Hi Jason. Welcome to the turning vortex and SMC!

You are not alone. If you bought that Tulipwood in a store it was more than likely waxed and green. Unless their supplier kiln dried their wood (many don't) those types of blanks are almost always green no matter what the sales guy tells you.

Tulipwood does have a tendency to move as it dries when turned green. Whether it cracks or not is totally up to the piece itself. It is difficult to predict. There are various drying methods you can research until the cows come home but most folks (including myself) do exactly what you did: turn to finish in one session, try to get consistently thick walls (to make the drying even), and hope for the best.

The Tulipwood vessel in the link below was turned from a green, waxed blank. I turned it to finish in one session then let it sit for just over two weeks before doing anything else with it. Over that time it shrank on one axis (parallel to the grain) by about 1/4"! Looking down on it from above you can tell that it is no longer perfectly round. Luckily for me no cracking occurred. I'm not always that lucky.

http://www.sawmillcreek.org/showthread.php?t=49710

[Bernie Weishapl]

Welcome to SMC Jason. Yep I bet the wood wasn't dry. I had a piece do the same thing and was told it was a dry piece of wood. Mine wasn't finished yet so used CA and sanded a little for some sawdust. Looks pretty good.

[John Hart]

Welcome to the world of spinning beauty Jason!...and welcome to the Creek! Unfortunately...cracking is just one of those things that you bear the disappointment, maybe try to fix...and revel in the joy when it doesn't happen.;) Over time, you'll get the feel for it....these first cracks are learning experiences.

[Steve Schlumpf]

Jason, Welcome to the Creek! Looks like you already got all the info as to your tulipwood bowl. Any chance you can fix it?

[Jason Slutsky]

Thank you all for your fast replies and words of wisdom. I've attached some pictures of the bowl I spoke of in my previous post. That was my second project. The first was the wand. I got the lathe as a christmas present and previous to these things, I had just worked on tool use...making nothing in particular. Both are finished with a Beale buff. The spots on the bowl where the finish looks thin has since been fixed.

The wand has a mahogany handle and an olivewood body. The body is my second try. I broke the first one in half just as I was finishing it by moving the toolrest and starting up without checking clearance. Don't plan on doing that again. :-)

55525

55526

55527

[Jason Slutsky]

I'm not sure I want to try fixing it. It's a very small crack and doesn't structurally harm the bowl. Only visible from the bottom. Also, I don't have any technique for fixing things like this yet. In my non-turning projects I may use some gorilla glue, sand, and refinish. Bernie said he's used CA and sanding dust on an unfinished piece of his. Wonder if that might work for me?

[John Hart]

I'm curious Jason....Did you hollow out the bottom? If not, that may be the source of your crack. Those are two very fine looking projects! Mine were an embarrassment....yours are showable.;)

[Rick Levine]

Jason,

You might want to try some cyanoacrylate (CA) instead to Gorilla Glue, but the stuff meant for woodworking, not Super Glue. You can find it at alot of the woodworking stores or online. David Marks uses it for various repairs like keeping knots from falling out of some of his projects. Gorilla Glue is great for some things but the foam produced might not be the easiest to remove from your piece.

[Bill Boehme]

Jason, welcome to the big gulch, aka Creek. I agree with John about the reason for the crack. You should aim for uniform thickness throughout the bowl. If the sides are thin and the bottom is thick that is the ideal situation for stress cracks during drying because of the difference in shrinkage in the thin and thick parts.

It takes years for a thick turning blank to completely dry especially if it is waxed. The way around this problem is to partially turn it (called roughing) and then let it air dry for a few weeks or months before finish turning. There are different techniques involved that you need to read about.

Bill

[Bob Hallowell]

Jason,
I shop at west penn hardwoods in Olean, Ny. They are one of the major importers of exotic wood. They prolly sell to your store too and the tell me no turning stock is dry- except pen blanks. it's just waxed no kiln.

Bob

[Tom Sherman]

Nice turnings Jason, welcome to the Creek. I can't add to what has already been offered so will leave it at that.

[Jason Slutsky]

John,
I did cut a mortise into the bottom of the bowl so I could spread my chuck into it. I wanted the base of the bowl to be wider so I did this instead of cutting a tenon. Between the mortise and the bottom edge of the bowl is about .75-1"...that's where the crack formed.

[George Tokarev]

Go here and grab chapter three. Nice diagram shows the direction of warp characteristic to the grain orientation. http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/fplgtr113.htm You'll also enjoy reading about how wood dries, and learning how to avoid some of the pitfalls. For intance, vertical walls and a broad base are not a great combination. The warpage is a percentage of the contiguous board, meaning tapered sides will take a bit less diameter away overall, because there will be air in the middle rather than wood to pull against.

It's probably even money that you had a preexisting radial check which had closed again visually, only to open when the surface dried ahead of the ability of the water to move out of the face grain. That type would normally close with contraction across the grain. Did your mortise go oval along the grain? With the color pattern its a bit difficult for me to interpret the orientation of the annual rings. It's also my habit to store roughs on their bottoms so that the top can shrink and compress while the bottom stays expanded longer. Keeps some of those surprises at bay.