Hollowing tool advise.

[Ian James Webster]

Hi all,

I just picked up a great peice of burl that should make a stunning vase / hollow form (at least it would in the hands of someone with more skill than me!!).

Hoever, I've only been turning bowls and bottle stoppers so far and don't have any hollowing tools. I'd greatly appreaciate your suggestions for a hollowing tool. I don't have hundreds of dollars to spend so I'm hoping to find something inexpensive to learn on.

Thank you

Ian

[Mike Minto]

Hollowing tools, by nature being specialized, tend to be expensive. However, they're not all out of most of our reach. The Sorby Hollowmaster (two sizes, full and midi) is very useful for blind hollowing - they also make smaller, less expensive hollowers; but then again so is a 5/8" bowl gouge (for roughing, anyway). There is also the Elbo tool, not too expensive for an articulated system, and the Jamieson is probably the least expensive of the 'captured' systems (I use it and like it alot). Hope this helps, Mike (BTW, don't forget a drill chuck and forstner bit to initially drill the blank out - makes life much easier, avoiding having to deal with that little 'center nubby').

[Tim Rinehart]

If hollowing something like a vase, with a fairly generous opening...I can (and so could you) get away with a 5/8" bowl gouge pretty far using it in a scraper mode....basically opposite to what you're likely doing in making a bowl. If it is vibrating on you...realize you're probably too far in for control to be maintained.

As far as commercial systems...most are either the type with arm brace, which I've not used, but seems like it would have advantage in getting 'feel' of what you're cutting, or they are the type like Elbo (Monster also) or Lyle Jamieson where you are holding the tool with a device to control a catch...but also to allow use of a laser for watching wall thickness as you cut.

I use a system built on the Lyle Jamieson design, and his website provides much info on construction and design. These can be put together relatively inexpensively, and quite elegantly if you have access to any machine tools or a light duty welder.

My advice to anyone starting hollowing...start small, use something like the Sorby Hollowmaster as Mike suggested (swan neck or straight). The beauty of the Hollowmaster is the flat bottom that helps prevent twisting from catches. (the flats react against the tool rest to counter torque from catch).

It took me several weeks looking around at all the different designs to figure out what I wanted to do...and I decided on the ease of building a Jamieson style and I fashioned a laser to go with it. It works well for me...but that being said...I'd love to try out a Elbo/Monster type of articulated arm. Again, even these can be home built on a budget if you have access to some metal stock. Bearings are cheap or you could even just use sintered bushings at the joints.

Oh...be sure to practice on something besides that nice piece of burl, and be sure to post what you make with it!

Good luck.

[Ian James Webster]

Thank you Mike - I was looking at the full size Sorby Hollowmaster. I think I'll give it a try. If I get hooked (and you know I will) I'll upgrade later.

Thanks again.

Ian

[Allen Neighbors]

Thank you Mike - I was looking at the full size Sorby Hollowmaster. I think I'll give it a try. If I get hooked (and you know I will) I'll upgrade later.

Thanks again.

Ian

Ian,
For three years, I used an oland tool to do all my hollowing. One was straight, and the other one was a swan-neck. Now I use a homemade system with laser to hollow large forms... but I still use the Oland tools for nearly every smaller item with a small entrance opening.

[David Foshee]

I vote for the elbo tool. I have a Elbo tool with the laser and love it. I would recommed getting the laser. Keeps you from making a vase with two holes.

[Wally Dickerman]

First, I suggest that whatever you do regarding a hollowing tool, do a lot of practicing on plain wood before you tackle that very nice piece of wood.

My first hollowing tool I made myself. That was a case of necessity because in the early 80's turning hollow forms was just getting started and there weren't any commercial tools on the market. It was a simple boring bar. I bought a 5/8 inch square piece of mild steel about 12 inches long. I bored a hole in one end and installed a 3/16th inch square metal cutting bit. (the same bit that's used in many hollowing tools today) I secured it with a grub screw. Epoxy could be used instead. I installed this in a fairly long wood handle. Overall the tool was a bit over 28 inches long. I later made a similar tool with the cutting bit pointing out at about 15 deg. Because I got a little torque on this one I bored a hole in the end of the handle and put in some lead shot. Total cost not over $20.

Though the tools are limited to using a fairly large opening they work very well.

In my HF classes I have the students use a very similar shop made tool to start their hollowing. I used 1/2 inch square steel for this one. I suggest to them that they make one. Works great for the initial hollowing of most HF's. Just bore a center hole in the blank and cut from the center out.

Wally

[Edward Bartimmo]

In my mind there are two basic types of hollowing tools. There is either free handed tools or captured tool systems. In general terms without consideration for a turner's skill, the free handed tools, such as Sorby Hollowmaster or Ellsworths tools, are for smaller vessels, whereas the captured tool systems, like Jamieson and Kelton systems, are for larger (deeper or wider) items.

Serveral key variables impact the complexity of a hollow form:
1) Size of the vessel - Deeper the vessel the more torque encountered at cutting tip as tool extends beyond the tool rest/support requiring more strength and effort to hold and control
2) Shape of the vessel - turning tight corners or acute curvature is more difficult than a longer more gradual curve radius
3) Size of the the entry hole at top of vessel - smaller the hole the less room to maneuver tools and deal with tight angles
4) Type of wood - type of wood impacts difficulty (maple vs. ironwood), freshness of the wood (green is easier than dry wood), grain pattern of wood (burl,figured and wood with inclusions or voids is more difficult than a piece with straight grain)

Once you start getting beyond 12" - 15" deep into a vessel the torque at the cutting edge starts significantly impacting tool control if you are using free hand hollowing tools.

Start small and use some friendly wood like plain maple to get a feel for the tools and practice your technique. There are some great videos available on different tools and hollowing techniques. Have fun expanding your tool collection!!!