Hollowing tools

[chrisdaniels]

I want to get into hollow forms so i'm trying to figure out which tool to start out with. I don't like the captive bar systems because they're just too big so I want a handheld tool. I want to do medium/large hollow forms so i'm looking for some advice on which to chose. I have a couple of carbide scrapers, not real fond of them but I hear good things about the hunter tools. I'm thinking I should start out with a straight tool and then get a curved tool maybe next. below are a couple of them that i'm considering so what do you guys think?

Hunter no. 4
https://www.woodturnerscatalog.com/p/133/2636/Hunter-No.4-Carbide-Hollowing-Tool

Sorby
https://www.woodturnerscatalog.com/p/133/5557/Robert-Sorby-Bent-Shank-Multi-Tip-Hollowing-Tool

https://www.woodturnerscatalog.com/p/133/5556/Robert-Sorby-Straight-Shank-Multi-Tip-Hollowing-Tool

John Jordan
http://www.packardwoodworks.com/Mer...re_Code=packard&Category_Code=tools-jord-holl

 

[hockenbery]

My advice is to start small.
Make a bunch of hollow ball Christmas ornaments. These will teach the basics of hollowing.
A 2.5- 3" diameter ball you can hollow quickly once you get the hang of it.
When you go through the wall or break one. You won't have much time or money invested.
You will also be more willing to push yourself to turn a 1/16- 1/8 inch wall thickness.
An ornament hollowing tool with a cutter coming out of the bar at a 40 degree angle is all you need.
Hollow ball ornaments make great gifts and sell well.

For my big forms
I like the Trent Bosch hollowing bars.
I also started using the Bosch visualizer a great advancement in hollowing.
Easy to confidently cut the inside wall with precision.

The Jordan bars are similar to the Bosch tools. Both can be used in the Jamieson handle.
I like that the cutting tips on the Bosch tool insert with CA glue. I have had set screws come loose while hollowing
I have never had a CA glued tip come loose in just over 20 years of hollowing.

If you are having any issues with your back, shoulders or legs, consider the using the Jamieson handle.
Or something like the Bosch stabilizer.
You stand erect and no stress on any body parts to hollow.
Both the Jamieson and the Bosch stabilizer work well with a laser or TV setup.

The sinner system is nice too.

Best bang for the buck a Jamison handle, build a back rest from plywood, Bosch straight tool Bosch hook tool, some pipe and boat fitting to mount the laser.

 

[Richard Coers]

What does medium/large mean to you? To me it's 10+" diameter and 12+" deep. I can't give you much advice unless I know how far you want to hang over the rest or what diameter. Also what style? If you want to do southwest style or flattened shapes with a sharp return inside the opening, you'll need different advice as well. How thin of wall thickness? Using hand held is fine until you actually blow through the first several vessels because you can't sense the wall. I'd suggest you get your hands on some hollowing rigs BEFORE you make a purchase. Of the choices you give, I'd go with the John Jordan. BUT, I'd buy them directly from John instead of from a reseller.

 

[hockenbery]

A nice article on face grain hollow forms

American Woodturner Spring 2009 page 53

By John Jordan

 

[robo hippy]

If you are hanging out 6 to 8 inches, then a hand held hollowing system works okay. Any more than that and the leverage is a bit much for any fine control. I use hand held for roughing on forms up to maybe 8 inches, but above that go to a captured device. I use the McNaughton blades which work fine. Haven't really tried the others.

robo hippy

 

[Bill Boehme]

I have a set of Trent Bosch's hollowing tools and I think that they are very good. Trent now also offers similar tools with carbide cutters. Here is a link to his hollowing tools: http://www.trentbosch.com/catalog/product_info.php?products_id=166

I agree with Richard, Al, and Reed. They speak from experience and all have valuable advice. Starting small, as Al recommended, is definitely the smartest way to proceed. Turning hollowforms requires learning some skills . . . . . and turning good hollowforms takes more skill plus time to hone your creativity.

As Richard mentioned, the term "large" is something that conveys different ideas to different people. However, I think that most people would agree that large hollowforms are generally too large to be easily turned without some sort of stabilizer as well as larger diameter boring bars that aren't easy to use strictly hand held. Also, there is a practical limit to the length of "cheater" bars for hand hollowing. You need to be close enough to see fine details and also make fine adjustments. The largest of handheld tools start vibrating too much as the reach over the rest gets much greater than about eight or nine inches under ideal conditions . . . . if you are an expert . . . . . otherwise maybe six inches is a more reasonable upper limit for overhang.

As mentioned, the Jamieson rig is the best bang for the buck. While it's not as slick as some of the other rigs, the price is right and even more important is that it does the job. Lyle will either tell you how to build your own or sell you a ready made rig. If you already have the materials and know how to weld then you can save a few bucks, otherwise, I would highly recommend the Lyle Jamieson rig as the best and most convenient way to go. Beyond that are the "big boy" rigs if you find yourself getting really serious about turning large hollowforms.

 

[chrisdaniels]

Thank you all for your advice. By medium to large I meant anything from 4-12" wide by about 6-12" tall or so. I've ordered the Jordan set of 1/2" hollowing tools, good call btw on getting them directly from him, great deal (75$ for both). I am looking into the jamieson boring bar system but i'm going to wait until i've got some hollowforms under my belt that are of manageable size like recommended before I worry about making big ones. Thanks again!

Chris

 

[Richard Coers]

I think you will find that the issue you expressed that a captive system is "too big", is a problem that is easy to get used to when you gain so much control. Lyle shows how simple controlling his system is with just finger tip pressure all the time. You get tired, you just take your hands off it and nothing happens. The polar opposite of what hand held hollowers are like. If you have a sliding head lathe, you will be able to hand hollow off the end, but with a fixed head, you have more control issues with a hand held as well. Don't start with the large size, despite the temptations!

 

[Bill Boehme]

Chris, I Think that you will have quite a challenge in controlling hand held hollowing tools for a diameter or depth greater than eight inches.

BTW, there are hollowing systems that will fit on a mini lathe so "too big" is not an issue.

 

[hockenbery]

I think it is good to get a tiny bit of hand held experience then move on to a trapped system. Hand held works okay for people who do the same shape all the time.

It is just hard to get even wall thickness and a too thin spot usually dries with a wrinkle. Using a laser pointer or video makes it much faster and increases my confidence in knkwing the thickness of the wall. Some people can judge thickness by the sound of the wood, I cannot.

I use the Jamieson handle on small lathes like the ONEWAY 1224 or Jet 1221 vs
I have a length of 2x6 that I bolt through the ways with a block of wood below the ways.
The slots for the trap screw onto the other end of the 2x6

Did a hollowing demo last summer on a jet 1221vs. The hollowing goes fine. Roughing to round takes a lot longer on a small lathe because the lathe will bounce at a normal roughing speed for a small vessel.

A 6" tall form is a comfortable limit for a 1/2" tool.
With a 3/4" bar the distance off the rest goes to 8-10". I have an 1 1/4 inch bar I use for anything over 12" diameter.
You can stretch the limits of the tools but must take small cuts.

 

[robo hippy]

I have been playing around with scoops the last week or so. The scoop part is about 4 inch diameter by 6 inch deep, and that is a bit big for turning full length of scoop and handle, so I am doing them in 2 parts. I consider them good practice for getting the basics of hollow forms down. Nice because you can easily see what is going on while you are hollowing. Rough with the McNaughton hand held, and finish with a 1/2 thick by 3/4 wide negative rake scraper, which is excellent for clean up work and smoothing out sides and end grain.

Does any one use a NRS tip for the insides of hollow forms? Some appear to be so smooth on the inside, I figure there has to be some trick to getting a good clean cut. I do know there are ring and hook tools which can be used inside hollow forms, but most seem to prefer square or half round cutters.

robo hippy

 

[Pete Blair]

If you are not hollowing through a really small hole in end grain I don't believe there are many tools that make it easier than the ProForma. I am continually amazed that I get curlies in end grain. Yesterday I hollowed a 8" deep large 'cup shape in dry HARD maple and it was a wonderful experience. I have made a adaptor that allows me to use the 1/2" cutter in my 1" hollowing bar which of course makes for minimal vibration with the addition of a steady! Robo, this tool would work wonders with your scoops.

 

[hockenbery]

Pete,
I have done just a tiny bit of work with a hook tool.
I haven't used the froforma but it looks like a hook tool with a cover.
Is that correct? How do you sharpen it?

End grain hollowing cuts from the bottom center to the rim will cut supported fibers giving a super clean cut.
A gouge can't make that cut but a hook tool or ring tool can.

One of the guys in out club makes hook tool tips in about five minutes.

 

[robo hippy]

I went and googled it to check on it. It appears to be a hook type tool with a cover, but most of the hook tools I have seen orient in a shear cut mode, where this appears to be more of an inside peeling cut set up. I do have one ring type cutter with a cover on it, and never could get the cover adjusted properly. It either clogged up, or it wouldn't cut... Probably me, so this calls for more practice....

robo hippy

 

[Bill Boehme]

.... How do you sharpen it? ......

I have made a few hook tools and sharpen them using a cone shaped diamond hone that is used for sharpening mortising chisels. You can get a kit at Rockler Hardware, individual hones from Lee Valley or Peachtree. Here is a picture.



Here is a picture showing how the cone hone is used.

 

[Pete Blair]

Pete,
I have done just a tiny bit of work with a hook tool.
I haven't used the froforma but it looks like a hook tool with a cover.
Is that correct? How do you sharpen it?

End grain hollowing cuts from the bottom center to the rim will cut supported fibers giving a super clean cut.
A gouge can't make that cut but a hook tool or ring tool can.

One of the guys in out club makes hook tool tips in about five minutes.

You guys are correct. The ProForma is a hook tool with an adjustable cover similar to others on the market.
To sharpen it I only hone lightly on the ground side, not on the inside. Takes only a swipe or two with a diamond card to get it to cut wonderfully again.
Check it out here.
https://woodbowlsandthings.wordpress.com/2016/02/16/pro-forme-hollowing-tool/

 

[john lucas]

Well I'm kind of with the others. I have a home made version of the John Jordan hollowing tools and do most of my smaller work with them. Hard to beat them. When it starts getting deeper I go with a captured bar system. I just don't turn enough hollow forms to be really good with hand hollowing and the captured bar systems are just so relaxing to use. None of that white knuckle stress especially when hollowing deeper than 8". As far as space goes get one of the articulated hollowers like the Monster tool or Elbow tool. They store very compactly although my homemade Jamieson bar just hangs on the wall pretty much out of the way.
I have a fair amount of experience with hook tools, ring, tools and hunter tools (that i use lie the hook tools). The ring tools clog too easily on green wood, pretty good tools for dry wood endgrain work. Hook tools are incredible on green wood and will take large shavings. They do have a pretty good learning curve as do the ring tools. MY biggest gripe about either one was the hassle of sharpening. Ring tools are pretty easy if you have a cone shaped grinding stone like the one Bill showed. You can also use those on hook tools but it's easy to change the tool cutting angle. I sharpened the hook tools mostly with a diamond fish hook sharpener but it takes considerably longer.
The Hunter tools work really well once you learn what you can and can't do with them and which ones to use. The #4 you showed in my opinion should only be used tilted to one side or the other at about 45 degrees and used as a bevel rubbing tool. Used flat with the face up it will give you one gigantic catch. For hollowing the Hunter #1 cutter mounted in either John Jordan bar or Lyle Jamieson style swiveling captured bar is a really great tool. Cuts very fast and never needs sharpening. You will have to replace the cutter occasionally if you use it a lot. The Hunter Hercules and Osprey can be used flat like a scraper or can be tilted to one side and used as a bevel rubbing tool just like a push cut on a bowl gouge. The downside of those tools is the shaft is too short for serious hollowing. That's why he makes the #1 cutter. Mike also sells curved hollowing tools that are good but are designed for less deep vessels.

 

[chrisdaniels]

thanks for the advice, I got the bosch 16" handle and I really like it to go with the 1/2" JJ tools. I tried to hollow out a 10" cherry burl vase because I needed to take 1/8" more out than my forstner bit would and I can see why that size isn't for going that deep. I will probably get the jamieson bar once i'm ready for bigger hollowing. so far i've done a couple of small hollowforms, nothing very good though. I do have a question about vases and hollowforms. do you turn them green and let them dry then finish turn them also or just go for gold from green to finish? or is that like bowls and it's really just up to the turner to decide what they like best.
I've been trying to learn with my mcnaughton how to core bowls but I think i'm using blanks that are too small for coring. I have the regular size set of mcnaughton setup with the mark 8 turret and haven't gotten a useable core yet. i've been using 8-10" blanks 3-4" thick so are those too small to even bother coring out? I know it's a subjective question but does anyone have rough estimates of the size bowls, diameter and depth I should be cutting my blanks to so that I can get good useable cores. I'd like to be getting 3 bowls out of each blank so I can do sets.

some of the first bowls I rough turned are coming close to dry, and I have some thin natural edge bowls that have warped into really really oblong bowls that look really neat. so far I like turning the natural edge pieces thin from green and letting them warp but I don't much care for the way a regular bowl looks warped after turning it thin from green.

My mother in law secured me a 20' tall 2.5' diameter hard maple tree that needs to come out of someone's yard because they're doing landscaping. the top of the tree is cut off after 20' and all the branches are cut off allready, just have to cut it down and haul it off. pretty sure i'll get me a good number of bowls out of that!!!

Chris

 

[Bill Boehme]

When turning hollowforms it depends on what you want. If it's a natural edged organic shape then going for the gold and letting it warp is a good way to go. If you want a formal looking piece then rough turning green and letting it dry before final turning is the best way to go. In any event it's always desirable to do as much of the work as you can while the wood is green and easy to work.