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Randy Heinemann
07-24-2017, 8:57 PM
Is there any rule of thumb concerning which direction grain (growth rings) should run when turning a bowl. I am attaching a picture.

Is it best to have grain run so that the rings are cupped upward; sort of following the outside shape of the bowl?

Or is it better to have rings facing downward or toward the outside of the bowl (like a frown)?

Are there upsides and downsides to both?

Or does it depend on which the turner thinks will look best? (Hope it's not this choice since I have no idea.)

364440

Kyle Iwamoto
07-24-2017, 10:08 PM
Personal choice, when there is no sap wood and heartwood. When you look into the bowl, pith on the bottom will have rings, bark to the bottom (the way your picture is oriented) the grain will be "broken", not in rings. more like )( versus (). IF I remember correctly. I can never remember this answer.
If you have 2 similar blanks turn one each way and label them. At the least you will learn what grain direction while cutting will feel like. Maybe I should do that so I can remember.

Brian Kent
07-25-2017, 12:38 AM
When the top of the bowl faces the pith, you will get peaks coming in from two sides.
When the top of the bowl faces the outside of the log, you will get concentric rings.

Thom Sturgill
07-25-2017, 8:02 AM
I had a billet of butternut large enough to get two 8" bowls 4" tall. It was cut perfectly for bowl turning with the pith having been centered above the billet. I turned one pith up and one pith down to see the difference. While the pith to the bottom gave a pleasing set of concentric rings, the bowl was very plain. The bowl turned with the pith toward the top presented a very dramatic set of cathedals on two sides and the bottom was beautiful with side to side cathedrals.
As with any turning YMMV.

John K Jordan
07-25-2017, 8:04 AM
Is there any rule of thumb concerning which direction grain (growth rings) should run when turning a bowl. I am attaching a picture.
...Or does it depend on which the turner thinks will look best? (Hope it's not this choice since I have no idea.)


Randy,

Green or dry wood? If turned green and allowed to warp there is some difference in the final shape. Also, a bowl turned green with the bottom close to the pith might be more likely to crack at the bottom depending on several factors, such as the thickness of the bottom, how close to the pith/juvenile wood, and the stability of the species or specific block of wood.

The appearance of the rings varies widely and depends not only on whether the pith is at the top or the bottom and how close the pith is to the top or bottom, but on the radius of the bowl and in the case of the bark side down, how closely that radius follows the radius of the rings (smaller, larger, or close to the same). But in general, these pictures might help. I've seen better illustrations but these are the only ones I could locate just now.

364500
https://www.pinterest.com/pin/493144227934039289

364501
https://www.pinterest.com/pin/9710955429449644

JKJ

John K Jordan
07-25-2017, 9:27 AM
... turned one pith up and one pith down to see the difference. While the pith to the bottom gave a pleasing set of concentric rings, the bowl was very plain. The bowl turned with the pith toward the top presented a very dramatic set of cathedals on two sides and the bottom was beautiful with side to side cathedrals.


I have seen that too - some dramatic "hourglass" shapes on the inside of the bowl. The shape and position depends on how even or wild the rings are along the log and whether they are perfectly parallel to the base or if the slab was cut on an angle to the pith.

These two shallow platters (from the same slab of sapele) were turned with the pith toward the top, bark toward the bottom. I didn't photograph with the intent of showing the pattern, but I can still see the hourglass figure on the top one, the bigger one similar but wilder since it was not centered and the figure was not even. The shallow convex shape of the bottom did not, of course, match up with the radius of the rings.

Since the wide rims are convex from the top, it might be possible to see the oval patterns characteristic of what you see in the bottom of a bowl when the pith is towards the base.

364504

(Thanks to Frank Penta for this wood)

In general, because of this I prefer to turn with the barkside down. But for a particular blank, things like any distinctive figure in the wood also need to be considered (x-ray vision would help here!). I chose the pith side down orientation for this one on a guess that the ovals would make a more dramatic and interesting background for the strong fiddleback figure in the maple:

364505

BTW, the slight angle of the ovals axes to the squarish edges was on purpose in an attempt to keep the piece from looking too "static". Jury is out on how well that worked...
(Thanks to Ellis Walentine for the piece of wood.)

JKJ

Randy Heinemann
07-25-2017, 10:09 AM
Thanks to those who replied. Very helpful. Mainly I just wanted to be sure there were no reasons I wouldn't want to turn either way. The wood is dry. I haven't attempted any turnings with green wood. I am new to turning and find that there are a lot of things I don't know about wood when it comes to turning. Although I've been a woodworker for many years, I didn't start turning till about 8 months ago. So far, I'm sorry I didn't try it sooner.

Richard Dooling
07-25-2017, 12:38 PM
Nice explanation and supporting graphics John!

John K Jordan
07-25-2017, 3:47 PM
The wood is dry. I haven't attempted any turnings with green wood. I am new to turning and find that there are a lot of things I don't know about wood when it comes to turning. Although I've been a woodworker for many years, I didn't start turning till about 8 months ago.

Don't get in too big a hurry to turn green wood bowls! I have read and heard from several turning experts that if you want to build expertise, start with spindle turning. (From Richard Raffan, Jimmy Clewes, Mike Darlow, Keith Rowley, Frank Penta...) It turns out that spindle turning will teach you the fine tool control that will let you turn anything. It apparently doesn't work the other way. Compared to spindle turning, I find turning bowls pretty easy.

Frank said in the "trades", traditional turning apprenticeship in Europe, a turner had to spend maybe a year or so and become an expert in spindle turning before he was allowed to to start learning face/bowl turning.

When I start beginners the first tool in their hands is a skew chisel. We learn how to make planing cuts with the skew in less than 30 minutes. Since the skew is the simplest and most basic edge, it's the best way to really understand the relationship of the bevel to the cut. After the skew, we work on the roughing gouge and then the spindle gouge. Since with spindle turning the grain is longways on the lathe, it also provides a more uniform wood for the beginner instead of the alternating side and end grain of a face turning.

I have seen the opposite over and over - someone starts on the lathe and is seduced by the joys of turning green wood - easy cuts, big shavings flying - and never learns the fine tool control to make very light, controlled cuts that need minimal sanding, or turn thin and delicate things. But I know some people who only turn bowls and couldn't turn a spindle if they had to. Don't misunderstand - I'm not saying there is anything at all wrong with this - as long as the person is having fun and happy to turn bowls more power to them.

If you want to learn more about wood and how it behaves and read, the book "Understanding Wood: A Craftsman's Guide to Wood Technology by R.Bruce Hoadley" https://www.amazon.com/Understanding-Wood-Craftsmans-Technology-Hardcover/dp/B011SJ8HCO
I read this when I started turning (along with a few others) and it helped me a lot. I still refer to it often along with Hoadley's other book, "Identifying Wood"

JKJ

Randy Heinemann
07-25-2017, 4:39 PM
John, Thanks for the advice. I started turning now because my wife is a polymer clay jewelry artist and got the idea to inlay polymer clay in turned wood bowls. Because of this starting point, my main interest for now, is bowls. I don't find spindles very interesting. I have no doubt you are right; namely that turning spindles develops a wider range of skills. I really enjoy woodworking of all kinds and never turned until now because, frankly, I was intimidated by it and really like making other pieces a lot. I find now that I enjoy turning very much and like the fact that, to some degree, the final design of a bowl may not be exactly what I envisioned to start with meaning I am sort of creating as I go. That isn't an experience I get when I make furniture or cabinets or even a cutting board (or the custom cribbage board I made for my daughter recently). So, while I like turning a lot, it, so far, hasn't become something I do exclusively. I'm very satisfied with my improving skills with small bowls and am taking my time moving to larger ones. I bought a midi lathe that will handle 12" diameter bowls and sort of sorry I didn't buy a larger one because I can see that, at some point, I will want to turn something larger than that. However, I'm a long way from having the confidence to do that, so I'm very satisfied moving at the gradual pace I am. I do always appreciate the great advice I've gotten from turners on this forum. Every time I've asked a question, I've gotten a solid, useful answer in a helpful way. Thanks again.

Thomas Canfield
07-25-2017, 9:22 PM
Randy, I am a big advocate of practicing your bowl turning by using 2x6 construction lumber. It helps you read the grain and shows the difference of pith up or down, and the extreme difference between soft/hard grain will make you a better sharpener. Sharp tools are the key to satisfaction with your turning. I find scraps at building sites when rafters are installed, and end up with a wide selection of grain pattern in the 2x6 material. You are not creating any masterpiece, but after about 6 of same shape, you can definitely see improvement in both quality and also confidence. Lots of different shapes and techniques can be practiced in that manner. My normal preference is to have pith down if the pith is centered to get the grain rings. If it is off-center, then the grain pattern is not uniform and then best use of wood.

Randy Heinemann
07-25-2017, 11:34 PM
Thomas,

I appreciate the suggestions. I find, however, that I lose interest very quickly when I do something repetitively. It just doesn't hold the same interest and value for me. I have found that, after turning 9 bowls and 2 classes with an instructor who was very helpful, I have been improving steadily. Each bowl is a different shape so far and, for me, that's what kind of keeps it interesting. I haven't found anything yet that really has challenged me enough to just take some scrap and practice, practice, practice. About half my bowls have been made of scrap I would have shown away anyway so, if they would have self-destructed, it would have been no real loss.

Frank Drew
07-29-2017, 11:20 AM
Something else to consider, you can almost always get a larger diameter bowl if you orient the pith at the top, with the bowl shape mirroring the log shape.

Prashun Patel
07-29-2017, 2:08 PM
I learned bowls first and continue to struggle with fine cuts that don't require sanding. So there is some wisdom in Johns words.

Bill Jobe
07-29-2017, 3:47 PM
Is it best to start with one species of wood and stick with that for a while before moving on to the next?

John K Jordan
07-29-2017, 5:06 PM
Is it best to start with one species of wood and stick with that for a while before moving on to the next?

I think the basic control issues are the same for all species, from basswood to ebony. I prefer to experience as many different types of wood and situations as possible - I think it all builds expertise. (I keep well over 100 species on hand.) When I encounter issues with a new wood, extra hard, soft, punky, splintery, etc., I spend time trying different tools and techniques to help discover what works. One bowl, for example, should offer enough

I think the way get from start to finish makes a difference. I make almost every cut a practice cut - instead of getting in a rush hogging away wood maybe I'll see how perfect a surface I can get with the skew, then with skews ground differently. I discovered expert turner and friend John Lucas and I work very much the same way. Like me, John says as he starts on a piece he will often try different tools and cuts just to see how they behave. In the middle of hollowing he might try several different bowl gouge grinds. If tapering a 2" round down to 1/2", for example, he might turn beads and coves with skew, turn them away with a skew, turn more with a Hunter tool or spindle gouge, turn those away, etc. When hollowing the inside of a large bowl, pretend it is a small bowl at first and practice cuts and shapes with different tools.

When I start to approach the target dimension/shape on either spindle or face turning I make sure every cut is a finish cut, as controlled and smooth as I can manage. I might do 10 or 20 of these while reaching my final shape but by the time I do that FINAL final cut, my stance, hands, and motion are well practiced!

Of course, all this takes extra time. But hey, I'm retired! And have zero interest in cranking out things for sale.

JKJ

Thomas Canfield
07-30-2017, 1:59 PM
Thomas,

I appreciate the suggestions. I find, however, that I lose interest very quickly when I do something repetitively. It just doesn't hold the same interest and value for me. I have found that, after turning 9 bowls and 2 classes with an instructor who was very helpful, I have been improving steadily. Each bowl is a different shape so far and, for me, that's what kind of keeps it interesting. I haven't found anything yet that really has challenged me enough to just take some scrap and practice, practice, practice. About half my bowls have been made of scrap I would have shown away anyway so, if they would have self-destructed, it would have been no real loss.

Randy - Challenge yourself to do a better job with your practice using some square 2x6 sections of wood and then cutting the bowls to see the actual thickness and details. Just like playing golf is just going around 18 holes, turning a bowl is just making a round piece with hollow section until you put your touches and skill to work. Here is a photo of some of the scrap pieces made preparing for demo on learning to turn bowls using 2x6 lumber: 364992

Randy Heinemann
07-30-2017, 2:28 PM
I have found that, since I am still in the early learning stages of bowl turning, I put forth the most effort in trying to refine my cuts so that less sanding is needed at the end. I definitely have made progress on that and find that I have many less rough spots at the end; sometimes nothing serious at all. It gets better with every bowl I turn.

I get the most satisfaction and learn the most by trying to turn a somewhat different shape with each blank. While there are limits to the number of basic styles and shapes, each blank turns out slightly different whether the same wood or not (at least I convince myself of that), so each bowl makes me think about how to get from beginning to end and make adjustments along the way.

In fact, the differences in the end result and the variety of shapes I can make is what, for the most part, really interests me. It's so different than other woodworking like cabinets, drawers, furniture in that, for the most part, the design is there before you make it. With bowl turning, while you might have an idea of what you want the bowl to look like, that might shift during turning so that it ends up looking different for one reason or another. At least that has been my experience so far.

Rich Colvin
07-30-2017, 5:56 PM
John is right. There is a great book : Talent is Overrated: What Really Separates World-Class Performers from Everybody Else by Geoff Colvin (no relation). Geoff outlines how we must practice the things we do badly until we master them. It could be something simple like a pull cut with a bowl gouge, or starting to carve out the inside of a bowl. But it is the way that expertise is developed. That worked for me in shooting trap, and with turning it continues to work.

Good luck,
Rich

John K Jordan
07-30-2017, 11:11 PM
...There is a great book : Talent is Overrated: What Really Separates World-Class Performers from Everybody Else by Geoff Colvin (no relation). Geoff outlines how we must practice the things we do badly until we master them.


Rich, thanks very much for the book recommendation - I just ordered a copy from Amazon and can't wait to read it. (I am a certified card-carrying book maniac!)

I learned the practice/practice/practice regimen from music. I love piano but long, slow, boring, repetitive and painful practice is the only thing that works for me. For example I've played my favorite composition, Liebestraum by Franz Liszt, in recitals and my sister's wedding. But it literally took me well over a year of practicing every day to get to that level, sometimes for several hours at a time. I envy those who can master a piece like that in a few weeks but the effort I need is still worth it.

My piano teacher often said "everything's easy, once you know how." Yeah, right. Except for piano! :)

JKJ

Bill Jobe
07-31-2017, 12:30 AM
For example I've played my favorite composition, Liebestraum by Franz Liszt, in recitals and my sister's wedding.
JKJ

I love that piece.

Harold Balzonia
07-31-2017, 12:43 AM
This thread that started out with a relatively simple technical question has quickly become a philosophical gem of a thread! This thread represents exactly what I love about turning. It's the way experienced turners learn to go with what the wood gives you and not try to force a shape that the piece of wood is unwilling to give.

every time I turn something, I use it as an opportunity to learn something. Exactly as JKJ described. "What would happen if I....?" Is a constant refrain going around in my head. The "rules" of woodturning need to be fully understood before you can break the rules for a specific cut. Accomplished teachers like Lyle Jamieson might punch my in the head, but I find there are times when I don't ride the bevel, for example! On purpose! Egads, man!

For me, EVERY piece is a practice piece.

like so many areas of life, people want recipes to follow in order to get similar results. Woodworkers want cut lists, exact dimensions, step-by-step directions, and lists of exactly what kind of tool to use for every cut.... (and what angle the cutting edge should be sharpened to, and the best way to sharpen the tool, and how to get a secondary bevel, and then how to add a tertiary bevel, and each bevel needs to be cut with a different stone, oil stone? Wet stone? Diamond stone?........ Dear God! Make it stop!). In my experience, woodturning doesn't lend itself to that kind of thinking.

i can give you all the weightlifting workouts Arnold Schwarzenegger did, and you could follow every single one of them.... but you wouldn't look like him.

i can give you Gordon Ramsey's recipe for Beef Wellington, but yours won't taste the same as when he makes it.

there is nuance and subtlety and artistic sensibility in every wood turning. Finding your own path and your own way of traveling that path is the surest way to enjoy this endeavor for the long term.

The journey is much more important than the destination.

welcome to the vortex, Randy!

Randy Heinemann
07-31-2017, 2:17 AM
Well, many of us woodworkers "don't want cut lists, exact dimensions, step-by-step directions, and lists of exactly what kind of tool to use for every cut". Sometimes it is, however, a great experience to take a piece and try to copy it just the way it is as a test of your skills and whether your up to doing something new. Mostly I just love working with wood, whether it's making furniture, making a cabinet, just a piece of furniture or a storage piece for my shop; as I said, anything that is wood. I agree that turning is interesting because the final piece is sometimes a surprise to me and changes during turning either because I made a mistake, turned something too thin, or just because it didn't look right. However, the same thing happens with non-turned pieces. Many times I've changed something in the middle of making it because it just didn't fit the way it needed to or didn't look right the way I had thought it should be originally. For me, turning is just like all other woodworking I do in that it allows me to create something that I enjoy (and hopefully others). It's just me creating it whether it's something that started out as something I was trying to duplicate or something new I was trying to make. Anyway, I'm not taking offense. I just feel that turning isn't much different than all other woodworking. It's a way to create something from individual boards chunk of wood. I always find it amazing that, in the end, these boards or hunks of wood, turn into something useful, artistic, or just something to enjoy.

Rich Colvin
07-31-2017, 8:08 PM
I envy those who can master a piece like that in a few weeks ...
John, you'll like the book. I can't remember if it was this book, or Malcolm Gladwell's Tipping Point that outlines how there are no natural experts. Those who make it look easy have spent at least ten thousand hours getting that good !

Rich

John K Jordan
07-31-2017, 10:05 PM
John, you'll like the book. I can't remember if it was this book, or Malcolm Gladwell's Tipping Point that outlines how there are no natural experts. Those who make it look easy have spent at least ten thousand hours getting that good !


My favorite definition of an expert: Someone who makes all his mistakes in private....

I'm not an expert at anything. I make my mistakes right out in public.

JKJ