Bowl gouge tip shape...any advice please ?

[Keithie]

I have a 3/8 Robert Sorby standard bowl gouge (ie not fingernail) which I'm slowly getting better at using.

Its quite deep fluted compared to some bowl gouges I've seen on youtube videos...but thats how it is.

I've been trying to grind two different shapes at the tip...either pointier or flatter across (as seen from directly above) ..to see which I prefer and what the difference in gouge behaviour is like.

Given that neither my skill with grinding nor my skill with the gouge is either great or consistent (but getting better) it's difficult for me to tell if I'm fooling myself or not.

It seems, so far, like a flatter across, less 'pointy' nose is better in terms of flexibility on the majority of bowl cuts, but far worse (more difficult to maneouvre) at the transitions to the flatter area at the bootom of the interior of curvy bowls.

Is this just me? Or does a differing nose profile make some shapes of cut easier than others?

Any advice / opinions welcome
cheers

 

[CHJ]

Remember the comments Here and the link provided in that post.

 

[Robbo3]

Keith, a day spent having a lesson with a professional turner would work wonders for you & answer all your questions.

When grinding a bowl gouge you need to know what shape you are aiming for, so that you control it by where & how long you grind. At the moment yours looks like the bottom of a funnel ie straight sides which then start to flare out whereas it should really be a 'V' shape with a round bottom.

Bowl gouges
Flute shapes - https://www.peterchild.co.uk/info1/sflute.htm
Grind shapes - http://www.woodcentral.com/newforum/grinds.shtml

If you email me, I'll send you a copy of the Tormek SDV 186 Gouge Jig sharpening (20 pages 6.16 MB) which is probably the bible on how to grind wood turning tools. Seems they have removed the download link since I last looked.

 

[Keithie]

Thanks Chas ...it's exactly that comment...the bit about 'stick to one shape that works for you' that I'm focussing on. Makes complete sense to me. So I'm testing a few shapes (starting with two extremes then expecting to bias the compromise one way or other) to see which I like best ...but aware that I might be fooling myself about which feels/works better.

Cheers Robbo...pm sent with email address.

 

[SVB]

Basic bowl gouge grind, set rest to approx 45 deg, tool in line with wheel and just twist / roll tool to create bevel. Only thing you may wish to do, is grind the heel of the bevel off if your trying deeper bowls.

Worry about swept back / other versions later.

 

[duncanh]

I have a 3/8 Robert Sorby standard bowl gouge (ie not fingernail) which I'm slowly getting better at using.

Is this just me? Or does a differing nose profile make some shapes of cut easier than others?

Yes, that's the point of having different profiles. If they all behaved the same then we'd all be using pretty much the same profiles.
The trickiest areas are usually the transition between the steep walls and base which most beginners automatically seem to go far (feeling that they need to make the most from the wood they have). A blunter profile would normally be better for this but not necessarily as great for the rest of the shape.

If you want to experiment with profiles I'd recommend getting another gouge which matches the profile of the one you have. Keep one with the grind you have and vary the other so you can compare more easily. Otherwise you'll end up grinding your current gouge away to nothing in no time.

 

[CHJ]

For easiest and most effective access to deeper bowls you really need two gouges, one for the sides and a steeper nose for the internal bottom, the decision point as to which you are using depends on the transision curve between side and base and if the tool fouls the side walls of the bowl.

I'll take a couple of shots of my go-to gouges later, not saying they are what you need, everybody has preferred shapes, these will be mine for current tasks.

 

[CHJ]

My main profile.

The one for the internal bottom of bowls on the left.

Note how the heel of the gouge is relieved (double bevel if you like) to prevent it rubbing on the wood as you transition a sharp curve.

The two side by side.

As I say, these are what I work with, they may not be your preferred forms, so much depends on how you hold the tool and approach the cutting process.

 

[Dalboy]

Like Chas I have two bowl gouges one is the standard as brought and the second is a fingernail grind, they both cover anything I want them to do. As stated at the beginning of this thread stick to the standard until you are 100% confident using it and rather than keep changing the shape which will certainly mean grinding it down much quicker than normal buy a second with a different grind like a fingernail.
Once you gain quite a bit of experience then and only then change the shapes as needed.
With the standard grind you should be able to get a complete bowl with no trouble if not then look at your technique and again as stated get help even if it is not from a professional but someone local, have you thought about joining a club as there are many in them that are willing to help new turners. By doing so it is easier to see what is being said.
By all means keep asking questions on here

 

[Random Orbital Bob]

Keith - if you e mail me I can send you a presentation I delivered at our Turning club last month, the topic....sharpening turning tools

Might be quite relevant to your goals at the moment. It also includes slides from the Tormek chart and the Sorby pro edge playbook and in addition discusses the horseshoe method which is unbelievably useful as a technique to get the grinding of the wings in a fingernail grind correct. It majors on elliptical grinding but also covers Skews etc. This piece of work covers all the technical aspects of sharpening turning tools.

 

[woodpig]

Or alternatively Keith.

https://youtu.be/ZM4ak8ygzS4

 

[Keithie]

Thanks all, again.

Nice movie (again) woodpig .. I enjoy Robo Hippy ...he helped me learn about bandsaws too ! ..those tools of his are pretty fhunky in section .. I must have a look at the lower shelf of Sorby stuff at Yandles next time...they look like they may be scarily expensive tho ! One day I might just buy some bar and try shaping it!

Cheers Rob ...sent you a pm ..def would be interested to see your presentation

Thanks Dalboy again too.. I think thats exactly what I'm going to do ..stick with the standard grind with a medium-blunt point...no swept bsck edges or fingernail at this stage. There are a few clubs in Somerset ...but the nearest two are pretty much a 3 hour round trip which is a right hassle on a rainy winter night! My local pro is only a few doors away (literally less than 100 yards) so I def chat with him...he has somegreat kit ..but he works pretty hard pretty much all the time ..so there's only so much time I feel I can reasonably beg fromhim. Plus its great that there are so many folk on here with so much knowledge..I suspect with some stuff there's no hard & fast rules (tho some stuff there is of course) ..so lots of points of view are great..and when most folk do the same then its pretty obvious that its the way to go!

Very helpful pics again Chas ... I've been looking at pics of various profilesonline since ...hasreally helped the penny drop for me as to what the whole grind thing is about. Two (bowl) gouges seems like a very good plan too. Sticking with two sloghtly different profiles and a 'double bevel' is probably the way I'm heading.

Thanks Duncan... yesterday & today was the first time the penny dropped about the differing effects of differing shapes. Your quite right about the 'keeping most of the wood' thing as a beginner ...looking at what I've beenmsking it's definitely that way in hindsight...thinking about it it might also be to do with being prepared to cut more as I get more confident in what I'm doing...on my last little practice bowl I managed to make the underside concave rather than my normal gentle sweep which didnt do much more than take the corners off!

Thanks Simon too ...the 45 degree angle and simple rotation is what I'm aiming for ...to give a slightly blunt looking profile to the nose (which seems great at turning the inside of the bowl into giant tagliatelle lengths!). Having two gougeswith the different profiles seems like a pretty consistent message ..so thats pretty much my plan!

thanks all again
cheers
Keith

 

[Dalboy]

Someone who is a instructor in woodturning is Ed Oliver of Olivers Woodturning supplies down here in Kent he has made a video of using turning tools.

https://youtu.be/vArEv0elLzo There are plans for more.

He is good and I have had the pleasure to have seen his work as he is a club member of the club I belong to

 

[Keithie]

Thanks Dalboy ...thats a really nice video... he explains it really well. Its also quite comforting for me in that it shows that I've managed to put into practice the advice I've been given here correctly and dont seem to be getting anything wrong anymore (well, at least for the stuff he was showing how to do!).

I havent tried a straight ended scraper as a way of tidying theoutside of a bowl ..I must have a go. He seemed to be going from outside to in there (edge to centre) with it on the outside of his bowl. I guess thats against the grain ...is there a good reason do you think why he was going that way for a finishng cut ?...or maybe it was just a demo so he wasnt too worried about how it would look?

either way ...thanks for posting that

 

[CHJ]

When you are scraping to finish on the lathe, grain direction does not come into it, you are taking the merest whisper of material off with the sharpest edge possible in a sheering cut, on a flat scraper you idealy use the burr on the freshly dressed edge as the cutter, as you would in cabinet scraping.
When you get much more confident with tool control you can move to using the very freshly sharpened edge of the bowl gouge on its side, but this is not for the feint hearted and needs good tool control to avoid serious catches.
If you are finish scraping as opposed to just rounding up gouge bounce irregularities then you will get cotton wool fluffy wisps coming off the cutting edge.

 

[Dalboy]

Well the video of Ed Olivers I posted was the first he now has a second and is talking about the bowl turning tools

Bowl turning

 

[Keithie]

thanks again Dalboy .. funnily enough I was just looking for others by him yesterday but didnt find the one you've just posted. I will go watch!

edit : watched it ...its also really good ..thanks indeed and please do tell Ed Oliver his videos are great for beginners like me

ignoring the whole cutting with/against the grain thing..

- I liked the idea of setting your weight at your finishing point then physically rolling back to the start point...makes a lot of sense to me
- I hadnt heard of a superglue accelerator ... any recommended brands ?
- size of the screw for the screwchuck ... my axminster c jaws insert screw chuck has two screws but neither look very big, I'm thinking of turning an 8" round by 4" deep green oak bowl ...wondering if the screw in my axi jawswill be enough ? Is there any rough guidance / rule of thumb on size of screw to size of bowl?
- nice to see he had the same issue as I have when starting the gouge the far side of the bed ...hence the need for rotating headstock. I found Chas' solution (of trying to stay flatter and managing tool rotation more) is the best way in the absence of a rotating headstock
- I'm just starting to get the hang ofthe gliding thing towards final cuts ... nice to see its the right thing!
- so obviousreally ..but I hadnt thought of sharpening the tool just before a final cut !
- sadly he didnt show what to do about removing the chucking point whenthebowl was completed .. on bigger bowls (apart from hot glue & sacrificial chuck or titebond and time) I dont have a goodsolution either!

thanks again!

 

[Keithie]

also, thanks Chas re the direction of tidying with flat scraper (on cinvex and round scraper on concave) .. been practicing that too and the super fine dust and fluffy cotton wool stuff is nice to see ... my 2hp axi extractor & wide mouth funnel doesnt seem to grab it though (and I've stopped using the fan to blow it randomly round the workshop!)...but I guess its not rocket science for me to move the collector nozzle!

 

[Dalboy]

- I hadnt heard of a superglue accelerator ... any recommended brands

- size of the screw for the screwchuck ... my axminster c jaws insert screw chuck has two screws but neither look very big, I'm thinking of turning an 8" round by 4" deep green oak bowl ...wondering if the screw in my axi jawswill be enough ? Is there any rough guidance / rule of thumb on size of screw to size of bowl?

- sadly he didnt show what to do about removing the chucking point whenthebowl was completed .. on bigger bowls (apart from hot glue & sacrificial chuck or titebond and time) I dont have a goodsolution either!

thanks again!

I use Chestnut accelerator but be carful as sometimes it can turn the glue white depending on brand.

The screw chuck ed is using is the same as the one I use and comes with the chuck which needs a 3/8" hole drilled to accept it and not one of those that uses wood screw sizes which are OK for small items such as fruit

Once the bowl is complete you make a block of wood in the jaws into a dome shape to match close to the inside of the bowl place a piece of tissue/router mat over this and place the bowl onto it, bring up the tailstock and tighten up to the bottom of the bowl using the centre hole made with it from when turning as Ed did in the video. You can not turn most of the foot away remove and take the last little bit off with a chisel and sand by hand

 

[Keithie]

Thanks re the accelerator & screw chuck ... I think I might faceplate mount my 8x4" bowl ..at least I have the kit for that!

Havent tried jam chucks yet or indeed what you describe Dalboy ..which sounds similar but not exactly the same ... seems like a good idea that I get going with both of them ...thanks again!