THIS CRACKED ME UP

[mike calabrese]

Recently the owner of a gallery I have items placed for sale called to advise me one of my vases suffered damage. The pictures here show the failure in the form of two cracks in the cherry and resin feature ring. The construction is maple, cherry and epoxy resin and took about 6 weeks of off and on attention. The staves were built from blanks that included the center 3 stripe feature where the cracks generated. Using a fixture / jig the 5 piece blanks were carefully cut to create the required staves for the upper and lower sections. As you can see the upper section of the vase failed miserably producing two major stress cracks in the cherry wood components of the center stripe. I suspect there are at least two reasons for this failure. The gallery environment while a very fine operation is located in the basement of a 175 year old stone mill. The climate there as you can imagine is a bit unique over the seasons. Coupled with this I believe, the design on the upper section that I guess can be called an inverted hyperbolic shape greatly contributed to uneven stress and the failure. As you will see the failure was quite wide at the top tapering down to the resin feature ring and even caused progression into the solid resin casting. The finish was 4-5 coats inside and out of wipe on poly and given the gallery environment I assumed this would offer a reasonable barrier to moisture entry. I have at least 6 other pieces there many of which have been on display for months and are holding up well. I have cut the entire upper section from the base and will set the lower vase aside while i think of any further commitment of time and effort to the piece. As we all know gravity, rust and wood movement never sleeps.......... stuff happens.........lessons learned.

 

[Ryan Mooney]

Long vertical segments like that seem challenging. Finish slows down moisture movement but never really stops it so there’s that. The other thing I’d look at is the grain orientation, I think if I was going to brave trying to make on like this I’d make sure that at least the wider white wood segments were quarter sawn to minimize radial movement.

 

[mike calabrese]

Long vertical segments like that seem challenging. Finish slows down moisture movement but never really stops it so there’s that. The other thing I’d look at is the grain orientation, I think if I was going to brave trying to make on like this I’d make sure that at least the wider white wood segments were quarter sawn to minimize radial movement.

Yes there are soooooooooo many thinks you can incorporate but I feel at the end of the day it is a dice roll. So farI am lucky to be ahead of the game with 13 vases good and 1 bad vase result. Like it is a dice roll and sometines the dice are just loaded against you

 

[Vaughn McMillan]

On the plus side, at least you know your glue joints held up.

 

[Mike Stafford]

Back in the day when I was doing segmented work I learned what I knew from Don Russell. He was a master of using compound sawn staves mixed with traditional brick layers. His method was to cut staves from cross grain rather than ripping along the long grain.

One of the things I remember him saying is that when building a segmented blank you should never use a solid layer. The walnut layer that is at the base of the staves where one split appears to be solid. The staves expand left to right and right to left. The solid ring works to keep them from expanding and that can cause a split.

I turned quite a few segmented semi-enclosed hollow forms using Don's method and over 20 years later none have split. Cross grain staves expand vertically and are not affected nearly as much by the seasonal expansion of long grain pieces of wood. Here is a picture of one I turned in 2003.

 

[Ted Calver]

Sorry to see all that work and effort end in disappointment.

 

[David Johnson]

You guys are well above my pay grade. I wqouldn't even know where to begin. But I'm old so I don't care.
David

 

[Les Elm]

That's a bummer!!