Hollowing tools - which?

[rtyuiop]

Hi folks,

Think the time has come to finally buy a hollowing tool - looking for opinions, what's good?

Sounds like the rolly munro and vermec tools both come pretty highly recommended, and I do like buying from small local companies - well, NZ is close enough!

I do love very hard timber and also do a bit of work in epoxy, so something suitable or adaptable to match would be preferable to something that's mainly aimed at softer stuff.

Cheers,

Danny

[NeilS]

After trying few different ones, my preference is for the Woodcut power head.

See if you can try a few before you buy to see what works for you. If you lived a bit closer you could borrow some of mine to try.

Other than Woodcut's Irons Toolgate, which I really like for reaching into hollow forms, I'm not a fan of other hollowing tool capture support systems. My thoughts on that: if you are unable to control a hollowing tool freehand you are probably not yet ready for hollow forms...:o

[rtyuiop]

Thanks Neil - I've been trying to wrap my head around the woodcut toolgate... Does it just hold the tool in one spot above the bed, and then you control the tool by swivelling around the gate, and extending/retracting 'through' the gate?

[NeilS]

the woodcut toolgate... Does it just hold the tool in one spot above the bed, and then you control the tool by swiveling around the gate, and extending/retracting 'through' the gate?

Exactly.

And, as the post is held in the tool rest banjo, you can also manoeuvre that around to preposition the gate. As you can see from the image, there are also a number of holes along the bar to re-position the gate.

If I'm working on a hollow form that has a large enough opening to accommodate the bar, I insert that right into the form to give the give maximum support while hogging out the inside.

[rtyuiop]

Got it - thanks!

[tony_A]

Im not hugely experienced with hollow forms, probably done 20 or 30 so nowhere near in Neil's league. Most have been turned from old dry blackwood with knots, holes and voids. I love the look of this type of wood but turning it is hard work but by the time I have finished I generally feel like I have been worked over by Jeff Fenech.
I use a Rolly Munro hollower and find it is generally OK but blackwood chips tend jam between the cutter and the shield to the point where I don't use the shield. This makes the tool a little harder to handle and prone to digging in, particularly in any areas where it's cutting against the grain or if there is a void in the wood. These problems are accentuated with greater overhang from the tool rest. None the less I like the slicing action of this cutter. Up to about 200 mm of overhang it works pretty well.
I am keen to make some form of captured / articulating arm simply to ease the strain on an ageing body, and make some deeper vase's, but that's still in the design phase.

Tony

[turnerted]

The fact that there are so many hollowing tools on the market is indicative that no one has found the perfect tool yet . I usually use a system based on the woodcut powerhed as described by Neil for deep hollowing . For more shallow work , I often use the Leady hollowing tools .
Ted

[DAL1957]

I've been using the large Robert Sorby Swan Neck Hollowing Tool with reasonable success. Though it can be a bit of a wrestling match to keep it from rotating - need to keep your wits about you.

[NeilS]

..... can be a bit of a wrestling match to keep it from rotating

I added a bicycle handlebar side extensions (like this (https://www.google.com/shopping/product/483588282540789093?q=bicycle+handlebar+extensions&prds=paur:ClkAsKraX9izmLyQYOeEHks2RRgAhMPBpj1SMUJ2gTfyLr2O_YNdOYdzy5uG52iyKm-vb63FWTYKyHUw41Fl-wyl6e6Jb-dXb_B06ICkeV9B8WpLF86lb-eZPhIZAFPVH72xdcPv0MbxYq7St0IUYfoVM7XDFw&sa=X&ved=0ahUKEwia9KvFheDiAhXFL48KHS3sArsQ8wIIwwM)) to one of my first hollowers and that helped to control any tendency to rotate. Something like that could be added to any freehand hollower.

[NeilS]

.... I like the slicing action of this cutter.



I also prefer hollowers that slice (like Woodcut and Munro) for the bulk of the hollowing task. Many other makes use scraper tips of one sort or another. That's OK if you like to turn that way, it's just not my preferred way of turning. Some use a cup tip that does produce a 'cut', but many of them don't have the guard that can be adjusted for depth of cut. The Sorby Sovereign heads do have the adjustable guard, but not having used one I cannot comment on how well they work.

Of course, I do finish off with a fine scraping cut and for that my preference is for the Woodcut scraper head that can rotate in the shaft to the desired shear scraping angle... this one (http://www.timberlywoodturning.co.nz/products/Pro-Form-Hollower--Scraper-head-%28with-2-cutters%29-PSCR-.html). There are plenty of scraping tip designs that present the scraper tip horizontal to the wood, but as far as I know this particular scraper head is the only one that allows for variable shear scraping angles. Munro does have a shear scraping tip, but it is preset at 45deg. There appears to be a newer/another Woodcut scraper head design (this one (https://www.cwsonline.com.au/shop/item/woodcut-pro-forme-flexi-scraper-with-2-cutters)) but I've not used it, so can't say if it also allows for shear scraping angles, but it looks like it may.

My experience of the Woodcut and Munro heads (I have both) is that the Woodcut with its open sided cutter is less prone to clog, but all designs with an adjustable cutting guard will do so to some extent, depending on the condition of the wood.

Last point: You only need to bring the inside of a hollow form up to a touch finish as far as fingers can reach. The inside surface beyond that only needs to be finished to the level that an eye can appreciate peering into the dark interior of the form, which really doesn't happen all that often.

[Lyle]

This thread is a great example for a club to do a day of 'testing" of the hollowers the club members use. Get to see and try different systems. Not a put down of whichever you reckon is better/worse, but a good chance to see what is out there and have a go to see if brand x is for you...
Lyle.

[DAL1957]

I added a bicycle handlebar side extensions (like this (https://www.google.com/shopping/product/483588282540789093?q=bicycle+handlebar+extensions&prds=paur:ClkAsKraX9izmLyQYOeEHks2RRgAhMPBpj1SMUJ2gTfyLr2O_YNdOYdzy5uG52iyKm-vb63FWTYKyHUw41Fl-wyl6e6Jb-dXb_B06ICkeV9B8WpLF86lb-eZPhIZAFPVH72xdcPv0MbxYq7St0IUYfoVM7XDFw&sa=X&ved=0ahUKEwia9KvFheDiAhXFL48KHS3sArsQ8wIIwwM)) to one of my first hollowers and that helped to control any tendency to rotate. Something like that could be added to any freehand hollower.

Seems like a good idea. I have just ordered a set of eBay, now just have to wait for it to arrive, annoying really as tonight’s project is hollowing a potpourri urn.

[DAL1957]

I added a bicycle handlebar side extensions (like this (https://www.google.com/shopping/product/483588282540789093?q=bicycle+handlebar+extensions&prds=paur:ClkAsKraX9izmLyQYOeEHks2RRgAhMPBpj1SMUJ2gTfyLr2O_YNdOYdzy5uG52iyKm-vb63FWTYKyHUw41Fl-wyl6e6Jb-dXb_B06ICkeV9B8WpLF86lb-eZPhIZAFPVH72xdcPv0MbxYq7St0IUYfoVM7XDFw&sa=X&ved=0ahUKEwia9KvFheDiAhXFL48KHS3sArsQ8wIIwwM)) to one of my first hollowers and that helped to control any tendency to rotate. Something like that could be added to any freehand hollower.

Seems like a good idea. I have just ordered a set of eBay, now just have to wait for it to arrive, annoying really as tonight’s project is hollowing a potpourri urn.

[Old Croc]

Im not hugely experienced with hollow forms, probably done 20 or 30 so nowhere near in Neil's league. Most have been turned from old dry blackwood with knots, holes and voids. I love the look of this type of wood but turning it is hard work but by the time I have finished I generally feel like I have been worked over by Jeff Fenech.
I am keen to make some form of captured / articulating arm simply to ease the strain on an ageing body, and make some deeper vase's, but that's still in the design phase.

Tony


Hi folks,

Think the time has come to finally buy a hollowing tool - looking for opinions, what's good?

I do love very hard timber and also do a bit of work in epoxy, so something suitable or adaptable to match would be preferable to something that's mainly aimed at softer stuff.

Cheers,

Danny
Guys as someone said, there is no one size fits all. Over the last 30 odd years I have tried a lot, bought too many and then I decided to do deep hollowing and I don't have the strength to control them. So I searched the world, found several articulated setups but before I could buy one they disappeared off the market. I reckoned Trent Bosch made the best TC tipped tools, so I bought them and made the rest. This photo shows my rig with its adjustable handle and it eats harder wood easily.
Rgds,
Crocy.

[NeilS]

...then I decided to do deep hollowing and I don't have the strength to control them.



Fair comment Old Croc.

I guess that is what awaits all of us if we go the distance...:rolleyes:

[tony_A]

Guys as someone said, there is no one size fits all. Over the last 30 odd years I have tried a lot, bought too many and then I decided to do deep hollowing and I don't have the strength to control them. So I searched the world, found several articulated setups but before I could buy one they disappeared off the market. I reckoned Trent Bosch made the best TC tipped tools, so I bought them and made the rest. This photo shows my rig with its adjustable handle and it eats harder wood easily.
Rgds,
Crocy.

G'day Crock, I read somewhere that the commercially available articulated systems aren't as good for deep hollowing as a heavy captive bar due to vibration. Presumably this relates to the stiffness of the build as some of the articulated systems look a bit light. I find that once I get beyond about 200 mm overhang from the tool rest I start getting vibration. How deep can you go with yours in hardwood before you start running into problems. The design I have in mind would look something like yours but based on the "Kobra Hollowing System" using 2 knuckles built with something like 50 or 75 mm RHS and a 32 mm hollow bar that will hold a 16 mm hollowing tool. The 16 mm hollowing tool can be slipped inside the 32 mm hollow bar with about 100 mm stickout and the heavier bar run on the tool rest.

Tony

Tony

[Old Croc]

G'day Crock, I read somewhere that the commercially available articulated systems aren't as good for deep hollowing as a heavy captive bar due to vibration. Presumably this relates to the stiffness of the build as some of the articulated systems look a bit light. I find that once I get beyond about 200 mm overhang from the tool rest I start getting vibration. How deep can you go with yours in hardwood before you start running into problems. The design I have in mind would look something like yours but based on the "Kobra Hollowing System" using 2 knuckles built with something like 50 or 75 mm RHS and a 32 mm hollow bar that will hold a 16 mm hollowing tool. The 16 mm hollowing tool can be slipped inside the 32 mm hollow bar with about 100 mm stickout and the heavier bar run on the tool rest.

Tony

Tony
Tony, here is a photo of Trent's 20mm/ 3/4" total access tools including the new scraper I bought last trip and the extension bar I made. Yes they do sometimes chatter, but I made a micro adjuster for the height at the origin pivot post and by dropping the cutter height the base of the tool rubs and limits the cut. I have to admit to a very sphincter tightening moment on the 1st Camphor Laurel hollow form as it just hogged the wood out and was self feeding. It takes a bit of adjusting the speed of the lathe as well as the cutter height, but it works fine for me. Trent recommends using the straight tool, 2nd from the bottom to do 90% of the hogging out.
I can do 400mm/16" with it as in the original photo I posted and deeper with the extension in this photo, only limited by my bed length.
Why did I chose these tools?
The local woodturning competition limits the entry hole to 20% of the diameter of the piece and these worked the best. Not sure of the total weight of it all, but it's heavy and all the mass takes up the transfered forces. I saw a Simon Hope rig demonstrated at the Prossie Turnout and liked it and the Monster from the US, both good bits of gear.
As to your Kobra tool, I have not seen one in real life so not sure how it will handle our harder woods?
Rgds,
Crocy.

[woodtryer]

I too have gone down the Trent Bosch path. I don't use any support jig just yet but that's not to say i won't in the future. I find the 6mm carbide tip very easy to control and I would definitely recommend it to anyone wanting to get into hollow form turning.

Peter

[hughie]

I have a mix of free hand and captured systems 90% of which I have made my self. Mainly due to the fact I have found the bars are of a minimal thickness ... well from my perspective :U

So my main head type for hollowing is the Proforme from Woodcut. I have two heads one for roughing and the other set for a fine cut for finishing. Both of them are used on 20mm dia hardened steel shaft for maximum stiffness. They are ex linear bearing shafts and generally surfaced hardened and so can be worked quite readily.
I use the same dia on both hand held and captured rig is a type of Kobra with 3 or 4 knuckles, with either system I can get in around 400 if required as I am not much interested in going any deeper.
In order to minimise vibration over 250-300 I have a toolrest with a swiveling Irons Gate attachment set up, on the larger hollow vessel this gets shoved in about 3/4 of the way in to support the boring bar.

Sorry no images at the moment, the shed is out the back and it raining and darn cold. But I did post images up way back as I made this tools.

[Woodcrafts_UK]

Having tried many of the so called hollowing tools, I fully endorse the earlier comment about the Woodcut hollowers, primarily because they use a capped elliptical cutter. Rollei Munro and the old Exocet use the same form. This means you can hollow across the bottom of the form and up the sides without having to repositon the cap over the cutting edge. Circular cutters with a circular cap have varying amounts of edge exposed so you are continually going from minimal cut to real 'arm hangers'.
I would avoid any tool that has overly complicated heads, with fine adjustment dials and so on, as these require a larger entry hole, meaning you are creating a vase not a hollow form. Nor am I a fan of scrapers, be they high speed steel or carbide.
Regarding side handles, I just turned a wooden handle, glued in a stub of threaded rod and this takes the place of one of the shaft locking grubscrews. And one tip on this, make sure the handle is horizontal when the cutting edge is horizontal, so you can use the handle as a reference for the cutter angle.

[tony_A]

Sorry no images at the moment, the shed is out the back and it raining and darn cold. But I did post images up way back as I made this tools.

Would appreciate a photo Hughie if you think of it when you are in the shed, no tearing rush. Found an old thread where you were talking about the Kobra and building one but its prior to the great photo catastrophe. I ran an advanced search using hughie as the author and hollowing as the topic then did the same search with NeilS. There is a heap of archival material that makes interesting reading, spent a couple of hours reading old posts.

[Lewie]

Not sure if hey are available in your area but, if you get a chance to try the Easy Wood Tools hollowers, I think you'll be sold!

[rtyuiop]

I actually have an easy wood hollower already - it's a handy tool for very tough woods (and epoxy), but not much good for deep hollowing.

[NeilS]

Not sure if hey are available in your area but, if you get a chance to try the Easy Wood Tools hollowers, I think you'll be sold!Yes, they are also here. Like a virus, Easy Wood Tools have spread everywhere. They seem to spread by infecting the novice and stifling their turning development from there on.

They are just a carbide tip screwed to the end of a bar. If curious, make your own. I made my own version but only occasionally use it on dirty root balls (with stone inclusions) and the like.

I consider them to be a tool of last resort.

But, a bad habit to get into if used as a primary turning tool by novices. They will, IMO, stunt your turning development.



Sent from my ZTE T84 using Tapatalk

[mick661]

I totally agree with you Neil. it's not woodturning
Cheers Mick

[Lewie]

Yes, they are also here. Like a virus, Easy Wood Tools have spread everywhere. They seem to spread by infecting the novice and stifling their turning development from there on.They are just a carbide tip screwed to the end of a bar. If curious, make your own. I made my own version but only occasionally use it on dirty root balls (with stone inclusions) and the like. I consider them to be a tool of last resort. But, a bad habit to get into if used as a primary turning tool by novices. They will, IMO, stunt your turning development. Sent from my ZTE T84 using TapatalkActually, I've found there isn't anything I can't do with the Easy Wood Tools (except sharpen them). My turning abilities have expanded with their use. Their new negative rake cutters are perfect for acrylics.

[NeilS]

it's not woodturning


I'm not sure that I would go as far as that, Mick...:U

But what I can say is that last year I spent ten days with a bunch of the best woodturners in the world who had hundreds of turning tools between them and I didn't see a single Easy Wood tool among them. That must say something.

It is probably time to have another discussion about cutting vs scraping, which is what Easy Wood tools do, but this is not the thread for that. I might kick that off in a few weeks when I have a bit more spare time.