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Trevor Mills
09-02-2018, 11:24 PM
I normally turn bowls but I've been asked to produce some large end grain vases 16 - 20 inches deep, and I'm having a hard time hollowing them out with my bowl gouges. I was thinking of getting a Oneway termite but have heard bad reviews. Any suggestions on an appropriate hollowing tool that won't break the bank.
thanks.

Mike Nathal
09-03-2018, 7:50 AM
16 inch deep requires a 1 inch diameter boring bar (or 1 inch square). 0.75 inch diameter bars are only to good to about 12 inch depths. I don't think a hand held tool would work, you would need a captured rig. Jamieson, Steve Sinner, Carter all make versions. Unless the mouth of the vase is so wide that you can stick a tool rest inside. There are some specialty tool rests that are maybe 1-2 inch wide and several inches long that can be used for wide mouth vases. In that case a home-made Oland tool of the right length would be my choice.

John K Jordan
09-03-2018, 8:13 AM
I normally turn bowls but I've been asked to produce some large end grain vases 16 - 20 inches deep, and I'm having a hard time hollowing them out with my bowl gouges. I was thinking of getting a Oneway termite but have heard bad reviews. Any suggestions on an appropriate hollowing tool that won't break the bank.
thanks.

I had a Termite but eventually gave it away. I thought it was OK for the insides of smaller things but in my hands it was prone to clogging, can't imagine me using it to remove a significant amount of wood, especially 20" deep. That's a serious hollow form! Most of my own hollowing has been quite modest and I get good results with a variety of hand-held tools, mostly from Mike Hunter.

For moderate forms, I have the tools and arm brace that the other John Jordan sells: https://www.johnjordanwoodturning.com/John_Jordan_Woodturning/Tools_and_More.html This easily good to 6-8" deep.

Deep hollowing is another story. Many people doing deep hollowing use small scraping bits, say 1/4" across or so, held in a long, strong tool handle/support with some means of keeping it from twisting when deep in the inside. Some of these are handles with an arm brace, but even then 20" deep might be challenging. I don't have one, but a "captive" system fastens to the lathe and uses some kind of frame or mechanism to control the torque on the tool when deep inside a form. Various types of these are available commercially but can be shop-made as well. Google captive hollowing system for examples and information.

David Marks did a huge one a couple of years ago. I followed the saga on Facebook at the time but can't find a good photo of his rig at the moment. A little is here:
http://www.djmarks.com/sensei/
I think David also teaches a hollowing course in his shop. Something like that may be an excellent way to get up to speed. (And fun too!)

Lot's of people who read SMC have and use hollowing systems. I'm sure they will respond to this thread soon! You might search this here for past discussion and recommendations.

JKJ

John K Jordan
09-03-2018, 8:25 AM
n that case a home-made Oland tool of the right length would be my choice.

I forgot to mention that some people will make a deep vessel by cutting it in half, hollowing both pieces, then gluing them back together. This would be far easier to turn, working from the middle.

This method may require some creativity to avoid an obvious seam. I watched Mark Gardner demonstrate this at a symposium - he usually decorates and paints the vessel so the seam is invisible. Here is a description on one website: http://www.carolinamountainwoodturners.org/articles/34

I have an unopened set of the genuine Oland tools on my shelf if someone wants them real bad! (I'll probably never use them.) Easy enough to make from scratch, though.

JKJ

Dane Riley
09-03-2018, 12:38 PM
For moderate forms, I have the tools and arm brace that the other John Jordan sells: https://www.johnjordanwoodturning.com/John_Jordan_Woodturning/Tools_and_More.html This easily good to 6-8" deep.

Deep hollowing is another story. Many people doing deep hollowing use small scraping bits, say 1/4" across or so, held in a long, strong tool handle/support with some means of keeping it from twisting when deep in the inside. Some of these are handles with an arm brace, but even then 20" deep might be challenging. I don't have one, but a "captive" system fastens to the lathe and uses some kind of frame or mechanism to control the torque on the tool when deep inside a form. Various types of these are available commercially but can be shop-made as well. Google captive hollowing system for examples and information.



JKJ

Deep hollowing with and armbrace is a good way to dislocate your shoulder. I came close. I won't use my armbrace for long over the tool rest or with a curved tool. You need a captive hollowing system.

Geoff Crimmins
09-03-2018, 5:44 PM
You might check out these hollowing tools designed by Steve Sinner, who turns a lot of deep hollow forms. http://advancedlathetools.com/ Their website tells how deep you can hollow with the different sizes of boring bars. It looks like you'll need the 1-1/8" diameter boring bar if you want to hollow to 20". You would also need the appropriate captured tool rest, and probably the laser attachement.

Dane Riley
09-03-2018, 7:06 PM
You might check out these hollowing tools designed by Steve Sinner, who turns a lot of deep hollow forms. http://advancedlathetools.com/ Their website tells how deep you can hollow with the different sizes of boring bars. It looks like you'll need the 1-1/8" diameter boring bar if you want to hollow to 20". You would also need the appropriate captured tool rest, and probably the laser attachement.

And that's with a Monroe hollower.

Joe Meirhaeghe
09-03-2018, 7:28 PM
I do a lot of work with Steve Sinner in his Studio with him. We do collaborative vessels anywhere from about 3" to 30" deep for several galleries
. Geoff is correct that it would take the 1 1/8" dia. boring bar to do 20" vessels. I would highly recommend his system with a Rolly Munro cutter if your serious about deep hollowing & plan on doing a lot of it. They are very heavy duty systems meant for serious work. He has a lot of very happy customers who would give you a good recomendation.

You might check out these hollowing tools designed by Steve Sinner, who turns a lot of deep hollow forms. http://advancedlathetools.com/ Their website tells how deep you can hollow with the different sizes of boring bars. It looks like you'll need the 1-1/8" diameter boring bar if you want to hollow to 20". You would also need the appropriate captured tool rest, and probably the laser attachement.

Peter Blair
09-03-2018, 8:56 PM
If you keep trying to hollow that deep with hand held tools you will eventually have shoulder/arm problems. I know the bank is not limitless but I believe you really need to buy/make a system.

Tom Giacomo
09-03-2018, 9:38 PM
If your as cheap as me here is a homemade one.392770

robert baccus
09-03-2018, 9:52 PM
I've been deep hollowing for 25 years--a homemade Jamison type to 20" deep. Went to a Woodcut heavy hook bit with a limiter also--no catches or "gumups" to worry about. It also leaves a quite smooth interior--I have done hundreds of vases and urns this way. Also very handy for tough deep troublesome bowls for arthritus fans.

Doug Hepler
09-03-2018, 10:53 PM
Trevor,

Have you considered segmented turning, either flat segments or staves? You specified end grain hollow forms. Actually, staves will give you end grain at the top and bottom of the form. You can lay up flat segments or compound segments a few rows at a time. You need to remove much less wood and do not need to go that far into each section. John Jordan mentioned cutting the blank in half but worried about the seam showing. You could consider making the seams part of the design. Making staves can be simple -- four rectangular blocks glued togeter around a hollow center -- or complicated -- a 12-sided polygon. If you want to learn more, google Malcolm Tibbetts

Its a matter of what you like and what you are good at. I do not enjoy hogging out end grain. With all sincere respect to earlier posts, I would not even attempt a "brute force" end grain hollow form such as you are considering. I recognize that many accomplished turners have not tried staved blanks. Some think that cutting staves and gluing them up is way too fussy compared to brute force approaches. It is still worth considering as a solution to your problem.

Doug

John K Jordan
09-04-2018, 8:55 AM
I recognize that many accomplished turners have not tried staved blanks. Some think that cutting staves and gluing them up is way too fussy compared to brute force approaches. It is still worth considering as a solution to your problem.

Here's a money-making idea for someone who likes cutting and gluing (and money!): Sell staved and segmented ready-to-turn pieces to turners who would rather turn than measure, cut and glue. Hey, I'd buy one - I've never tried turning one.

JKJ