Pith wood turning

[Dave Lehnert]

Fine Woodworking video showed the turner using a small 4 or 5" round log turned into a vase. Pith wood and all. turned like a spindle, then chucked to hollow out.
I thought using the pith wood was wrong and would only cause spiting. What is your experience?

[Richard Allen]

The pith will expand. If the pith is off center, which is likely in a piece that small then the pith will usually bulge out on the sidewall. The turning needs to be thin enough that sidewall is flexible (up to 1/4" on some woods as thin as 1/8 for some woods).

Note that different wood react differently to the drying process. Even woods of the same species from different trees or even different parts of the same tree can react differently.

[Dennis Ford]

The only success that I have had with pieces that include the pith have been turned quite thin and allowed to warp. Usually the pith dries faster and cracks, but it shrinks less than the rest of the wood often resulting in cracking the outside. The piece of almond that Kathy posted earlier is an example of a shape that has a good chance of survival as the pith has room to move without cracking. I have friends that turn pieces including the pith that are not thin with some success but this takes carefully controlled drying (and some luck).

[Baxter Smith]

I have turned several end grain vase shapes and boxes that way. If the pith at the bottom of the vase is soaked with CA inside and out and is not too thick, they may have developed tiny cracks but they are not particularly noticeable.

[Bernie Weishapl]

I have used CA with pretty good success and also have mounted the vase in a donut chuck to finish the bottom. If the pith is centered I will cut out and plug with a piece of the same wood.

[Dave Lehnert]

Is Elm better or worse? I have a bunch of Elm trees.

[Dennis Ford]

Elm is better in the sense that the interlocked grain is crack resistant but worse in the sense that it moves more than most other woods. Overall, I like elm for turning (not so much for flat work).

[robert baccus]

I guess i'm the lucky one. i've turned dozens of endgrain vases with no more cracking than usual. my problem with cracking is more with lips but double waxing seems to help. one thing i do that may not be common is that i always glueblock endgrain pieces and this may help. i do this primarily because CA holds so good on green wood whereas screws can be a problem in the soft stuff. this probably holds things together to some degree. on green vases i usually turn, hollow and wax only the inside. i have this wierd theory that it actually pulls the wood together.----------old forester Dennis, are u having jetty fever or allready on the bank???

[Jamie Donaldson]

Turning with the pith "in" is not wrong, but higher risk. Whether end grain or side grain, with most woods the end grain will more likely be high risk, and turning thin is the best solution in both orientations. With the pith oriented horizontally, I have had several Elm pieces pucker out like footballs, and believe it really enhances the "howdhedodat" form.;)