Internal shaping?

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Munty Scruntfundle

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Hi folks.

So yesterday was the first real go at getting back into things, it's been a few years. This first block was a load of crumby old pallet wood glued up, cross grained and clamped overnight. I was actually quite surprised how the relatively cheapo tools started cutting and I was happily throwing shavings all over the place. I have to admit my plans for an elegant bowl with sweeping lines fairly quickly turned into Pooh Bear's honey pot, but I achieved what I intended, scrap wood into something nice looking and useful.

The only area where I struggled a little was the internal cutting, I just couldn't get a really clean cut. I should explain my left arm was mashed a few years ago, it's half metal and my elbow is weak, also damned painful. It's difficult to closely analyse what's going on while you're shoving a sharp thing up a hole, but my theory is I'm not able to steady the tool enough on the rest on a deep pulling cut, I had better results reversing the tool and working on the back side, maybe not ideal but I found I had more control.

While I've turned many years ago I wouldn't by any means say I got particularly good at it, and I put myself firmly into the "***** with a new toy." category.

Well, this turned into a waffle!

I know this is a pretty general question, and without listing every tool, the problems with an unconventional wheelchair sitting position, a table made of scrap wood, gaffer tape and bent screws -which would be tedious- any advice?

Many thanks. :eek:)
 
I would suggest you investigate using carbide tipped tools in boring mode simulating more of a Metal lathe approach to removing internal material until you have removed enough to use a round or rounded nose scraper to smooth the internals.

With the latter, a heavy thick, not necessarily wide tool located firmly on the tool rest means most of the loads are taken by the rest and you are not trying to maintain optimum bevel contact as you would with a gouge.

90% of my internals are machined this way.
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Including this one.
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If you use a Round Carbide cutter (on a tool such as shown above) for the internal Scraper function to blend curves make sure it is Flat Topped, not cupped, the latter can be very aggressive and need using with considerable circumspect if used without specialist shielded boring tools that prevent them diving into the wood.

I've been using such cutters since 2008 for roughing out and truing up awkward pieces, at that time the availability and sources was limited but they are plentiful now from numerous sources.
 
The key to a smooth surface, with the minimum of sanding, is "riding the bevel". I had the same problem as you (still do to a lesser extent...). I had some lessons and my teacher could turn the inside and outside of a bowl to virtually finished with just a bowl gouge. Practice, practice, practice....

https://turnawoodbowl.com/riding-the-be ... explained/
 
selectortone":3bjrqwu1 said:
... I had some lessons and my teacher could turn the inside and outside of a bowl to virtually finished with just a bowl gouge. ...

Not so easy if you have limited use of your limbs and body movement and deep hollowing to a high finish can be virtually impossible or very risky trying to use bevel contact methods if you can't lean right over the lathe/have a swivel headstock or can't turn left handed with lathe in reverse.

I personally think it's more satisfying for someone just starting to complete items to a reasonable standard regardless of how it's achieved (nobody is any the wiser when seeing the finished item) whilst they learn techniques and so called 'best practice' rather than get frustrated and disillusioned with failures.
 
I am working on a vase type piece of turning at the moment using Oak which is reasonably hard the tool I use without too many problems is the Revolution tool as shown HERE by Mark Sanger who also sells them.
You can get a good finish straight off of the tool but it still will need finishing as you would after using any other tool.
 
Thanks for the feedback guys.

I did indeed use the more metal work approach, as if moving the carriage towards the chuck, and with carbide too, square to dive down and round to finish.

Yes if you're purist the carbide is cheating, and I'm sure a better finish can be achieved with a good quality tool and the perfect technique, and I really do respect that. But, I want to enjoy making things, not so much learning how to learn to make the things. If that makes sense!

I think practice is the key, and learning my limitations. I don't think my sitting position at the lathe and arm strength (weakened further by position) are going to allow me a lot of depth.

And yes, practice. Lots of it.
Thanks again. :eek:)
 
Given that this is more about ergonomics than turning per se, (and I'm not a turner, so wouldn't know), would changing the height you work at make a difference? It struck me that, from a sitting position, the workpiece may be higher than if you were standing. I appreciate that lowering the lathe, or highering you would be problematic in its own right, and there would be issues with legs getting in the way.

Just a thought from outside the box, as it were.
 
Many turners in a similar postion use captive rigs to hold the tool. These are similar to how the cutter in metal turning is held and take away the requirement for pressure down on the tool rest.
 
Munty,
Have a look on the internet for Tony Wilson, he is a ‘wheelchair woodturner’ and may have some articles wrt tool holding, presentation and home made jigs.

Dave
 
Expensive, but Simon Hope's hollowing jig would mean you could work using very little pressure. Really easy to control and nearly all pressure taken by the rest and the jig.
 
I can thoroughly recommend Lyle JAMIESON`s hollowing rog, have a look on You Tube for his videos, you can hollow internally literally using a finger to guide it, not counter pressure need from able bodied or those less able - so would be emminently suitable for your situation - I have had mine for a few years now and have yet to find anything even close. It could be fabricated by a reasonable engineering workshop, but when I looked into that the cost saving was minimal to purchasing direct from Lyle. If your ever in darkest Norfolk you are welcome to have a play on the VB36 and the rig, the coffee isnt bad either. :)
 
Dave Brookes":2s8c1w1o said:
Munty,
Have a look on the internet for Tony Wilson, he is a ‘wheelchair woodturner’ and may have some articles wrt tool holding, presentation and home made jigs.

Dave
+1

I've seen and talked to Tony a number of times, he's a skilled turner, regular demonstrator and nice guy to boot.
i can't see where you live but if within reach or the Harrogate show next month he's usually there.
 
Just thought I'd put up a quick reply on this topic.

The idea came from Mr Waldt on the Tube. Kudos Mr Waldt, love your stuff.

I don't know if he's covered it, but I was him using a very swept back scraper for some internal work, a goblet I think, he likes a goblet! So I took a scraper gave it some reshaping, pointy-er tip and swept back around an inch. You have to be careful with it, it wants to cut, but it's made getting to the bottom of pots and goblets really easy. It's big and flat, I can keep it from bouncing. I just have to finish up the corners of pots.

I know some people aren't so keen on scrapers, but with some playing about I've found if you just touch the top side with a stone after sharpening (the opposite of what you should do) you remove some of the grab, cutting is slightly harder but the results are more predictable. It's also reduced the amount of sanding I'm having to do. A lot!

Just thought I'd share what I'd found. Do let me know if you agree or think I'm going in the wrong direction.
 
You are not doing it wrong at all, just remember if you have the scraper FLAT on the rest for support to keep the cutting edge ABOVE the centre line on internals, then if it grabs the tool will be driven into space not deeper into the wood.

Converse on the outside, on or below centre.

Scrapers were in use long before anyone used a Bowl Gouge.
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