End Grain Koa Crotch Vase

[Emiliano Achaval]

This customer brought over a nice Koa crotch, very large and long. Not a problem... I tried to show him how many bowls I could do, but... He wants a large end grain vase, with the crotch as a natural edge... Does anybody has any pictures of one that they have done? Any sketches? Thank in advance. Aloha

 

[hockenbery]

If you google "crotch bowls warren carpenter" you will see examples of his work.
i did not see any in his current gallery.
Warren demoed his crotch bowls at the AAW symposium in Tampa.
Here is what you might find with Google above Carolina - demo
http://www.carolinamountainwoodturners.org/articles/452

Todd Hoyer did a lot of these along time ago.

End grain produces wings that follow the the curve of the tree.
The wings can be really long.
So you need to start with a crotch that has nice looking curves on the two leaders,
These bowl can be dramatic and sculptural an usually Very tipsy.

I personally much prefer the face grain crotch bowls which are useable like the bowl below.

 

[Emiliano Achaval]

Very good information! Thank you.

 

[hockenbery]

@Emiliano Achaval
Working with a customer who "wants" a particular thing can be a challenge within itself.

The endgrain crotch bowls are are challenging to turn and it is sort of like turning close to an airplane propeller.
The end grain does not show the crotch figure so wood with a strong sap ring Is often used.
The curves of the blank are also import since the outside profile will be followed somewhat.

I would strongly suggest trying a small crotch to work through the process.
Todd Hoyer used a flat board with notches in each end pressed between the two crotches to allow tailstock support.

The face grain will show the feathers figure found in crotches between the two piths.
Have fun and work safely.

 

[olaf Vogel]

You said the crotch was wide but not long.

I've done a few such bowls and the propeller analogy is a good one.
This one was scary since its 28" across using a 4" jaws on a Stronghold (biggest I have...).

Make sure you are "in the zone" when stepping up. 🙂

Buts its very do-able:
1 - cut the foot and bottom shape to loose some mass
2 - flip it around so you can use a chuck.
3 - Drive in the tailstock and hollow most of the top, leaving a centre support

When you finally pull out the tailstock support, most of the weight is gone and the piece is fairly balanced.
(this one still wasn't...)

I didn't take enough pics when cutting that one, but part of the process is here.

I absolutely LOVE this one from Warren Carpenter

I think its in the book "500 Wood Bowls" which is a great reference for when I get stuck on design.
But oh so humbling...

Olaf

 

[Emiliano Achaval]

Did I mention that it needs to be a crotch vase, at least 14 inches high? Lol. I know, I hate custom orders... I also hate when they pick a dry rough turned bowl and have to finish it... thanks foro all the help!

 

[Bill Boehme]

Your customer did all the hard work for you. 😀 They found the piece of wood and figured out what to turn. Your job is simple ... just remove the wood that isn't part of the customer's vision. 😛