Had a nice catch / dig in earlier this week

[graduate_owner]

Hi everyone,
Just a short comment about the gripping qualities of Axminster jaws. I had a piece of unknown wood from the firewood pile and was having a go at bowl turning. Now it is usually the inside that gives me trouble but this time the outside was rough as anything. The wood was a bit tatty in places but I was quite determined to try for a decent finish. I decided to see what my Crown ring tool would do - what a mistake to make!! Within a few seconds it dug in, there was a load bang, and the ring just broke away, totally trashed. The bowl ( didn't look a lot like a bowl now) had a huge chunk out of it, but the thing is, those Axminster jaws didn't let it shift at all. Rock solid. To be honest I would have preferred the bowl to come away and perhaps not end up destroying my ring tool. Anyway, impressed with the gripper jaws, the ones with grooves on the inside, not the dovetail type.
Does anyone know why this might have happened - is the ring tool only for inside bowls, or was it just my usual ham fisted self?

K

 

[Phil Pascoe]

I'd have thought so. Did you have the tailstock done up?

 

[finneyb]

Designed for inside hollowing in end grain http://www.robert-sorby.co.uk/b845133-ring-tool
As you now know !!!

Brian

 

[graduate_owner]

No, it was just held in the jaws because I had been doing a bit of hollowing out. Scary event though, I don't usually get a fright from dig ins because, unfortunately, they are not such rare events in my shed, especially when hollowing out end grain. Outside of bowl though, I thought I was reasonably competent. Not so it seems.

And yes, now I know, so if I buy another ring tool I will keep it for the insides of my bowls. Expensive lesson learnt, but no personal injury, that's the main thing.
K

 

[graduate_owner]

I suppose without my ring tool I will have even more hassle when hollowing end grain now. Great. I might just invest in some large saw tooth bits and drill the insides away, or is that cheating?

K

 

[Robbo3]

Well you certainly found out the hard way that a ring tool is really meant for end grain hollowing.

Two other tools that shouldn't be used on cross grain work ie bowls & platters are the spindle roughing gouge & the skew chisel. The clue is in the name & is why it should have spindle in it's title.
The skew can be used on it's edge to incise a small vee or on it's side as a (negative rake) scraper.

Saw tooth bits are regularly used by some pro's for speed, especially when the depth exceeds 50mm.
Remember, when your masterpiece is on display, nobody will know how you hollowed it out or (in my case) that sanding started at 40 grit. All people will see is the finished article.

 

[Phil Pascoe]

The experienced turners I know drill a hole to near the finished depth then pull the waste out with a 3/8" spindle gouge.

 

[Dalboy]

I only ever use a ring type tool on the inside for the outside I use spindle or bowl gouges, and as you know presentation of the tools is also very important.

Nothing wrong with drilling a hole to near the depth of the vessel it just makes it easier to hollow out I certainly drill and it is a great way to give you a guide to the depth you require to go to if you drill down to just short of the final depth not forgetting any centre tang on the bit.

 

[CHJ]

I regularly speed up internals removal on Bowls by drilling to near finished depth taking due care about the centre spur depth as Derek mentioned.
I also take the liberty of removing the bulk of the material by boring it Metal Turning style with a rigid Carbide tipped tool if it's a large quantity or there are irregular features that could make bevel contact problematic.

I treat the outside of rough blanks, especially ones with knots or branch protrusions similarly until they are a reasonable curved form to allow easier Bevel contact with a Bowl gouge.

Not a Bowl in progress but an example of how I use the Carbide tool in straight-on Bore Mode, kept sharp the Carbide cutters can leave a pretty good finish and are not influenced by dissimilar wood hardness etc.

(Note:- Tool Rest should be closer to reduce overhang and leverage, a bit of photographic licence at play trying to balance tool and click the shutter.)

 

[graduate_owner]

Thanks for the responses guys. I have been thinking about buying some HSS blanks for making my own turning tools, well I have a handle and steel stem ready now. I might try the carbide approach. Expensive way of doing it though, that ring tool wasn't cheap.

Regarding hollowing out end grain by drilling, I think I will give that a go, just to see how things turn (!!) out. It has always been problematic for me. The largest saw tooth bit I have is nearly 3" diameter, but I think that will need some more punch than my 1HP wood lathe motor can deliver. Perhaps I will put it on the colchester, that lathe has a 3 HP motor so should be enough guts. Worth trying anyway.

CHJ - are those carbide tips specially made for woodturning, or do you just use metal turning tips?

K

 

[CHJ]

CHJ - are those carbide tips specially made for woodturning, or do you just use metal turning tips?

Yes they are a different spec. carry a much sharper edge neared to Brass or Ali, inserts.
Mine are the Ci1 inserts but there are other brands available in the UK now.

Just a rub across the flat top every few weeks on a diamond stone or card keeps them in good order. (finger slicing sharp!)

 

[Dalboy]

Regarding hollowing out end grain by drilling, I think I will give that a go, just to see how things turn (!!) out. It has always been problematic for me. The largest saw tooth bit I have is nearly 3" diameter, but I think that will need some more punch than my 1HP wood lathe motor can deliver. Perhaps I will put it on the colchester, that lathe has a 3 HP motor so should be enough guts. Worth trying anyway.

K

You don't need to use a large diameter bit the main reason I drill is to give ease of turning out the bulk by working from the drilled hole to the outside and working down the form, This is easier than trying to make a centre hole with the tool. Also I drill to give a depth guide.

 

[CHJ]

... The largest saw tooth bit I have is nearly 3" diameter, but I think that will need some more punch than my 1HP wood lathe motor can deliver. ...

You can open up the bore in steps using the bits.

If accuracy of final hole is not important you can just put a cone in the face of the turning and this will help centralise the bits that don't have a centre location. Can be seen in this old WIP

Alternate if finished hole size and location is critical you can go a bit more laborious route and open up reducing diameter shallow steps, then when you take out the next size up the step acts as a location for the bit.

 

[Robbo3]

Try Glenn Teagle for carbide bits. Free postage if you buy 2 or more.
- http://www.ukwoodcraftandcarbidechisels.co.uk/

 

[TFrench]

I've just bought a set of the glen teagle tips. I milled a flat in the centre of a bit of 12mm bar and cut it in half, giving me 2 tool blanks. Drilled and tapped for M4 screw (comes with the tips) and relieved the back with a grinder. Made a handle today and put it together - hey presto! carbide tipped tools for £7.
https://drive.google.com/file/d/1f45k1c ... sp=sharing