PDA

View Full Version : Birch vs Oak vs Maple Plywood



Smokestack
27th August 2007, 08:35 AM
I am planning a large, 24-36 inch id decorative vessle made of laminated birch, oak, or maple rings. These are available at my local giant home center. Has anyone had any experience turning these and if so which turns the easiest?

OGYT
27th August 2007, 12:56 PM
I've never turned any plywood myself, but I've seen some and it really looked good... you could tell it was plywood, but it really looked nice.
I would suggest getting cabinet-grade plywood, it'll have fewer voids that have to be filled.
Fast speed and light cuts, I think, would be in order.

Skew ChiDAMN!!
27th August 2007, 03:53 PM
One thing with ply is that the inner layers, which aren't normally seen, tend to be made of the low quality sheets. This means that there are occasionally areas where you'll not only get voids and tear-out but large splinters coming adrift, no matter how sharp your tools are.

The glue is also very, very hard on the tool edge... it usually means a lot of time spent at the sharpening station. Between these two "problems" I really don't think it makes much difference which wood is in the ply when it comes to saying "this is better/easier than that" while turning them. :shrug:

However, as OGYT said, it can be a worthwhile exercise: I've seen large hollow forms built up from laminations of ply and they looked good. Still obviously ply, but nice. :) (Not that I've done any large build-ups myself, but I have used ply laminations as features in smaller vessels.)

joe greiner
27th August 2007, 10:21 PM
I've seen some sculptures made of laminated timber, some several feet high, with the layers horizontal. From the look of them, I'd guess they make their own "plywood" from selected veneers. To reduce waste, you could cut rings in 90-degree segments (for example) with half of them (almost) long grain and the other half (almost) cross grain. When joined into rings, the join should be substantially invisible. The (almost) orientation would allow for a running bond (like brickwork) overlap for stronger construction than having the segment ends of individual layers aligned. And, you could use a more turning-friendly glue.

I could be wrong (of course!), but I think I know where the sculptor's studio is here in Tallahassee. I've wanted to have a chat with them to explore such possibilities as you're considering, but I haven't got a round tuit yet.

Al's suggestion of using cabinet-grade plywood would give fewer (if any) voids, but in some products the outer (face) plies are quite thin and could stand out like a sore thumb in a multi-layer buildup. Select such material carefully.

Another possibility would be to take a chance with ordinary plywood. These would generally have more uniform layer thicknesses. Fill the voids when and if they present themselves; or be prepared to make a few turnings and select the one that comes out without voids. Careful selection of the material would be beneficial here also.

{Google [woodturning plywood] produces many, many hits.}

Joe