Bowl turning technique - grain direction

[Keithie]

Typically when one buys a bowl or a spindle blank from a well established seller the grain is in an expected direction.

If I cross cut a spindle blank and round it up to make a 'bowl blank' (which is mostly what I've been doing) then the grain is the in a different direction to the 'normal' bowl blank. I think this is then termed an 'end grain' bowl blank (as opposed to 'side grain') ...but I may not have the right terms.

My question is whether there's much difference in technique for turning a bowl from either 'end grain' or 'side grain' bowl blanks (obviously a bowl or spindle blank could in theory be cut in any direction vs the grain).

I seem to find it much easier to turn 'normal' (side grain) bowl blanks ...but wondered if thats just me!

 

[Phil Pascoe]

Turning end grain is harder just as planing end grain is. You biggest problems will be distortion and probable splitting. Obviously screws won't hold so well in end grain when mounting, so don't rely on short ones for much.

 

[CHJ]

Typically when one buys a bowl or a spindle blank from a well established seller the grain is in an expected direction.

If I cross cut a spindle blank and round it up to make a 'bowl blank' (which is mostly what I've been doing) then the grain is the in a different direction to the 'normal' bowl blank. .....I seem to find it much easier to turn 'normal' (side grain) bowl blanks ...but wondered if thats just me!

If you must go against well established millennia old best practice and convention for wood harvesting and use strength wise expect to have greater difficulty machining it. A bit like trying to split a log for firewood by chopping across the log.

It's almost tantamount to deciding to deliberately drive everywhere in reverse, it isn't going to be long before a major incident happens to you or the car.

I personally would put the proportions of grain direction change to the unconventional and expect to get away with it in the same proportions as driving direction, and fully expect it to provide extra challenges and risks of needing repairs.

Turn a platter or a tool handle from end grain section (a slice across a log) and you will be able to snap it in half with one hand.
Turn a bowl from the same whole log slice and the chances are it will have a hole or at lest star splits in the middle of the base where the core was.


Sorry if that sounds very condescending, but think about it, and you will answer your own question with your own observations.

 

[Random Orbital Bob]

To put it more basically Keith:

Bowl blanks (also called face or side grain sometimes) have the grain running at 90 degrees to the axis of the lathe.
Spindle blanks (also called end grain sometimes) have the grain running parallel to the lathe beds (axis).

It's all about strength in the final piece. If you hollow into a piece of end grain and leave thin walls, you can imagine cant you that the grain is looking up at you when you look down at it. If you pinched the top of that thin walled vessel with your fingers, you could snap it very easily. If you had hollowed the same project into the blank with its grain side on, now as you look down at it, the straws are stacked on top of each other and you would struggle to snap it with your fingers.

End grain hollowing is a useful technique because it sits hand in hand with part of a spindle which of course means the turner can do other decorative things to it (like turn the detail in the stem of a goblet for instance). Or turn interesting finials in a lidded box in a very tight grained wood like Box or Maple etc.

But if you want a strong bowl that will hold up to long term use AND have a hope of maintaining its shape then you need to scoop out the side of the grain.

In terms of the methods/techniques for cutting the two different blanks....completely different approaches are needed. With bowl blanks, assuming you're using a deep fluted bowl gouge, you can do both push and pull cuts. But the push cut ie where you start at the rim and hollow out to the middle as you go is a very handy cut indeed. it allows the removal of a huge amount of stock (hogging off) and it can leave a very clean "cut" surface as its a bevel rubbing cut. It's very controlled and frankly a joy to do, long ribbons of shavings flying over your shoulder if the work is still green One of my favourite cuts in fact. It also allows you to carefully control where the inner surface of the rim will be.

This cut is impossible in end grain! That's the biggest difference. So with end grain, you're cutting into the ends of the straws and you need to start hollowing in the middle (typically with a spindle gouge) and then sweep round to the rim. It can also go fast but it's definitely a more frisky/catchy procedure than as described above. Also, once you've got to even a moderate depth, as the tool hangs further over the rest, it gets much more tricky and people start employing scrapers or dedicated hollowing tools with very long handles to cope with the tremendous forces of leverage.

In short, if you want to produce end grain hollow forms then I would recommend you stick to shallow hollowed projects while you learn, that means things like goblets, lidded boxes, ring holding dishes, egg cups etc.

For "proper" bowls ie a 12" salad bowl or similar, always always always choose side grain blanks and your life will be full of love, harmony and good luck

 

[Dalboy]

Having read many of your posts I think you tend to over think things and as a beginner I would suggest that you stick to the standard turning until you get more experienced for example keeping bowl blanks with the grain across the the lathe and spindle work with the lathe. Practice your tool work until you are happy using them safely.
I am self taught and started with the Keith Rowley book A Foundation Coarse in woodturning which I found a mine of information.
As you progress you will learn many things that as a beginner you would not even attempt it will slowly come eventually. This does not mean that you should stop asking questions.
Bear in mind what CHJ said. For end grain hollowing it depends on the shape of the bowl whether you have a inward turned lip which would mean cutting in different directions so as to cut with the grain.

 

[Random Orbital Bob]

Keith....not sure what your work schedule is like, but if you want, you're welcome to come to my workshop and we can spend a couple of hours drinking coffee....er I mean working through some of the techniques discussed. There is no substitute for a bit of one on one and it should hopefully demystify some of this stuff.

My fee.....one pack chocolate Hobnobs (must be milk chocolate too).

I can do this in the week also.

 

[Keithie]

Thanks all.

The advice and suggestions are much appreciated...and I obviously do recognise that you know a heck of a lot more about it than I do. Hence me asking so many questions. And continually receiving very helpful replies. I dint feel patronised / condescended to at all... I take the replies to be as I believe they're meant ... helpful & supportive and based on a lot of experience.

I'd agree that its just common sense to go with the flow and accept traditional wisdom in almost all fields ..for any number of reasons. I'm sure woodturning has evolved to what it is today for goid practical reasons and it makes sense for novices to follow a traditional learning curve until skill levels are high enough to recognise and manage the risks safely.

I guess sometimes the grain pattern looks like it might be better one way than the other .. but I havent started slicing diagonally through spindle blanks to try and capture multiple features ..but have thought about it!

You're quite right that I primarily take an intellectual approach ...though it is combined with practice ...I've turned about 60 items in the last 10 weeks (the benefit of being retired!). I guess some folk like me are just more intellectual than practical ...but that's ok...I enjoy both turning & thinking about turning (lol ..I dont think I've started dreaming about turning yet tho!)

At least I understand why I've been struggling with the bowl gouge !

Thanks also for the kind offer Bob...I'll drop you a pm.

cheers

 

[Keithie]

some end grain stuff from this month ... I'll try some side grain for a fair while now!

 

[woodpig]

Nice work Keith.

 

[Keithie]

Nice work Keith.

Thanks .. I know they're by no means great (the 'cups' are primarily for finish testing and will end up glued together as a spice rack type of thing)
..but at least they record where my starting skill level is ...hopefully In years to come they'll be a happy reminder of how much I got improved!

 

[woodpig]

Here's a nice end grain bowl.

https://youtu.be/gGoarTYOqSo

There are plenty more examples on YouTube. I think more people would probably turn end grain bowls but the material doesn't seem to be avalable very often. Carbide tools work quite well on end grain, at least on the small stuff that I've done.

 

[Keithie]

Thanks .. I enjoyed that video ...the hook tool looks fun! lol...he made a right dog's breakfast of that bowl with it ...lol! Makes some of my work look proper professional

 

[Robbo3]

In Chas,s reply, click on Web-site then 'Projects & Aids', then 'Log-Turned Item Growth Ring Patterns'. This shows you the orientation of the growth rings & what happens when you make a bowl from various places within the wood.
It's a PDF file so you can save it to your device.
- http://www.quest42.co.uk/woodwork/html/projects.html

 

[MusicMan]

Many things are spindle turned, mainly (1) when the length of wood required could never be found in a tree and (2) when the wood is stressed in bending; chair legs, banister rails and usually the finals, woodwind musical instruments, broom handles. Some of these have quite intricate shapes, but they rarely have hollowed-out ends other than holes along their lengths. Even the bells of woodwind instruments are usually made in bowl orientation even though the bulk of the instrument is spindle turned. But if you like the end-grain pattern and can manage it, no reason why you shouldn't. I think an end-grain bowl is a bit more likely to split on drying out, if it has been turned somewhat wet.

 

[woodpig]

Here's another good one. End grain bowls in Cherry.

https://youtu.be/-1tmeEOf3b4

 

[andy43]

Hi Keith
Saw your post and thought I would have a go at an end grain bowl as I had a rather large slice of horse chestnut which was destined for the firewood pile and still is, anyway gave it a go and was surprised how different it was to turning a conventional bowl blank, would I do this again? simple answer is no, I will stick to normal bowl blanks as its far easier, I didn't have the pith to contend with either, anyway a couple pics its approx. 11" x 2.5" deep.
cheers
Andy

 

[Phil Pascoe]

Don't forget also that if you use dovetail spigots or recesses the dovetail will be short grained and therefore weak.

 

[selectortone]

Here's another good one. End grain bowls in Cherry.

https://youtu.be/-1tmeEOf3b4

Wow... great video - that guy is GOOD!

Might have a go at that. A bit slower though :mrgreen:

 

[Keithie]

Thanks Woodpig ...again...another top vid ...he's got skills ok! Made me smile how his gouge slaps around inside the bowl...thats what mine does...but he's (in the commentary at least) totally chilled about it...plus his bowls go for a little walk every now and then but its no biggie...lol

Cheers Robbo .. hadnt focussed on those before ...for me the most interesting part is that they examine the two cases whoch are like 90deg part ...but nothing in between.. I've still not figured out why (apart from 'dont be so dumb') I dont see anything on diagonal cuts across the grain.

Nicely cut Andy .. looks, to my not very trained eye, like you didnt mess up at all onthose cuts ...and 11" isnt so small for a bowl set the wrong way round. Is that a CA glue up in the internal bowl 8-9 o'clock area ? (almost mirroring position on the underside). I've not figured out the whole repairing as you go thing so I'd be interested to know how you think about that kinda stuff.

Phil....thanks again...you 've helped me a lot mate ...thats exacty what I found ...it's an interesting balance between overfilling the chuck and getting good grip. I was messing up with pokey little spigots on O'Donnell jaws (even long but narrow spigots ...still cant take the forces) then messing up with badly formed dovetails on Axminster C jaws ...but finally figured that if I get my skew 'scary' sharp (and I know sharp is a thing of debate) and am super careful then even in rough old green fir the dovetail is kinda good enough ...so long as I dont hack too fiercely at the turning!

Musicman.. I hadnt realised that woodwind bells are formed in bowl grain style ...interesting. I'm violin primarily (wife is piano and sax ,. go figure!) ..but I cant be doing withthe whole luthier thing. I dont know much, but I know when proper skills are needed! One of my long term plans is a marimba ...via windchimes (I'm kinda assuming my p/t will be able to 'shape to flat' pieces of wood after my bandsaw has almost got it right!)..but I'm just guessing that it's all spindle endgrain?

thanks all, much appreciated.
cheers
Keith

 

[andy43]

No Keith
its just a mark in the wood
cheers
Andy