Do you prefer rainbows, or horseshoes?

[Odie]

I'm talking about grain orientation when looking at the end grain view of the bowl block.....😀

For me, most always a horseshoe grain orientation works best........but there are times when a rainbow orientation works better.

It's easy to get stuck in a pattern, but I accidentally roughed out a spalted maple bowl yesterday in a rainbow orientation. This reminded me to pay a little more attention. There were three bowl blanks, all from the same tree, that were being roughed. The one that I accidentally roughed in a rainbow orientation is the best looking of the three.......that is, artistically/aesthetically speaking.

There are other times when I will choose the rainbow, because of flaws. Sometimes, it's to take advantage of an interesting aspect of the wood that otherwise would be lost near the foot. Once in awhile, I'd rather have some figure in the rim, rather than down below..........

But, the great majority of bowls have the best overall appearance with a horseshoe grain orientation. This is pretty much the rule, because a rainbow orientation will generally produce a finish grain pattern that resemble "circles within circles".......which is less appealing than the alternative.

ooc



(Just in case anyone is confused, horseshoe end-grain orientation is like this....U

Rainbow would be the opposite, by flipping that U upside down.)

.

 

[Gretch Flo]

rainbow vs horse shoe

Pics??? Gretch

 

[hockenbery]

Odie,

Do you mean rim to bark edge versus rim to log center?

For most twice turned bowls I choose rim to log center. With the grain balanced I get the hyperbola grain pattern in the bottom and I can get a larger bowl from the log. Also on this orientation the rim will have two peaks when dry which I don't like in finished piece and the turning when dry takes this away.

The warp is also quite symmetrical making return easy.

When I find a log with a flat side, I will often turn a bowl with the rim on the bark side. This produces a grain pattern of concentric ovals in the bottom of the bowl. I usually turn these once. The rims on these bowls tends to warp in a pleasing wave. Design of rounded edges of these rims works better for me with the wave than a sharp edge rim. The warp is not as symmetrical with the rim to bark edge so they are are more trouble to line up for returning. This is also obviously the orientation for natural edge bowls which I like a lot.

Crtoches lend themselves well to bark rim bowls. You get the crotch figure in the bottom and the bark side of a crotch is often sort of flat.

The bark up/down is always a conundrum In turning platters.

Al

 

[Odie]

Pics??? Gretch

Mornin' Gretch..........

The Oak bowl blank on the left is rainbow, and the Bubinga bowl blank on the right is horseshoe.

ooc

 

[hockenbery]

Odie,

I would call the oak bark up and the bubinga bark down.

The annual rings tend to grow in circles although in a blanks from really big trees there are occasions when a a valley forms on the outside of the log.

Al

 

[Odie]

Odie,

Do you mean rim to bark edge versus rim to log center?

For most twice turned bowls I choose rim to log center. With the grain balanced I get the hyperbola grain pattern in the bottom and I can get a larger bowl from the log. Also on this orientation the rim will have two peaks when dry which I don't like in finished piece and the turning when dry takes this away.

The warp is also quite symmetrical making return easy.

When I find a log with a flat side, I will often turn a bowl with the rim on the bark side. This produces a grain pattern of concentric ovals in the bottom of the bowl. I usually turn these once. The rims on these bowls tends to warp in a pleasing wave. Design of rounded edges of these rims works better for me with the wave than a sharp edge rim. The warp is not as symmetrical with the rim to bark edge so they are are more trouble to line up for returning. This is also obviously the orientation for natural edge bowls which I like a lot.

Crtoches lend themselves well to bark rim bowls. You get the crotch figure in the bottom and the bark side of a crotch is often sort of flat.

The bark up/down is always a conundrum In turning platters.

Al

Hello Al.......

I guess that would be an "iffy" question, and there are many things that may influence a decision. For quarter-sawn (where the grain is vertical) it wouldn't make a whole lot of difference, but I still prefer the horseshoe orientation depending on my gut feeling about the possibilities. This may differ with different turners, and I'm not saying one way over the other would be best for everyone.....it is, after all, a choice, and a preference.

Your choices, and my choices are influenced by different things, since I seldom have the opportunity to work directly from the log. There are few hardwoods available to me in my part of the country, so most of the wood I use is processed to some degree.......anywhere from very wet, to kiln dried.

ooc

 

[Odie]

Odie,

I would call the oak bark up and the bubinga bark down.

The annual rings tend to grow in circles although in a blanks from really big trees there are occasions when a a valley forms on the outside of the log.

Al

I can see we are using different terminology to describe the same thing.

ooc

 

[Gretch Flo]

rainbow/horseshoe

Thanks Odie -Now I see-was confused as I work from self harvested/cut logs. I like the bark up , as I like the concentric circles, and the natural edge and not turning away the crotch figure. Get a bigger bowl from bark down, which seems to be against what Al said. Rarely have planks unless I make them, Gretch

 

[john lucas]

Sorry, couldn't help myself
http://www.youtube.com/watch?v=kaxoaKwx8tU

 

[hockenbery]

Get a bigger bowl from bark down, which seems to be against what Al said. Gretch

Not sure what I said but you do get a bigger bowl with the bottom toward the bark and rim to the center of the log.
The bowl follows the shape of the log in rough sense.

It sometimes gets confusing. 🙂

Al

 

[Odie]

Not sure what I said but you do get a bigger bowl with the bottom toward the bark and rim to the center of the log.
The bowl follows the shape of the log in rough sense.

It sometimes gets confusing. 🙂

Al

Yep, right, Al.......

It does get confusing, considering everyone has their own priorities, and visions for a finished bowl. You are right that you will get a bigger bowl with bark down, rim facing the pith, or horseshoe orientation........and, that only is true for those intending to eliminate the bark and sapwood. I think from Gretch's point of view, she intends to leave the bark and sapwood with a natural edge left on. When seeing it from her perspective, she very well may get a bigger bowl, considering her own individual priorities.

I never intended for my observations to encompass everyone else's ideas of what is desirable.......I was speaking for myself, and the few who are turning bowls in a similar fashion, and may have similar goals as I do.

So far, I think this has been a good discussion, and it just goes to show very succinctly that there are many ways of applying individuality to our turnings. What one does, and desires, may be entirely different than other turners. It may include others as a distinct group, but not all others as a matter of applied theory to THE entire group of woodturners.

ooc

 

[Gretch Flo]

Bark up/down

Al/Odie and I see eye to eye,, just not communicating properly. I AGREE bigger bowl when rim is at the pith. Gretch