End grain orientation

[Brian Brown]

I'm just full of questions today. If anyone has the answer to this one, I'm sure it will be from, this group. I am trying to turn a few pieces in end grain orientation (grain running parallel to the ways). Some of these are pith in, most are from half logs (pith gone) Cutting the outside has been very easy, but the inside hollowing is another story. I have used a bowl gouge, and a round nose bowl scraper. Both seem to do well for a while (slow going), then I get a horrendous catch that rips the piece from the chuck. The catch usually takes some wood off the tennon, making it impossible to re-center exactly. A forstner bit in the drill press is even slower going. I like the look of the pieces, but I'm not getting anywhere in the small amount of time I have in the shop. Is this just one of those things I shouldn't try or is there a secret to cutting end grain? I was thinking dynamite, but that may be just a tad aggressive. :eek:

[David Walser]

Brian,

There are some "secrets" to turning end grain. Here are some of them:


Turn from the inside towards the outside. This is just the opposite of the way you'd normally hollow a bowl.
Try one of the many tools, such as the "Termite" from Oneway, that are made especially for turning end grain. Here's a link: http://www.oneway.ca/tools/termite.htm
Keep your tool supported. Reaching deep into a turning may require you to extend your tool well over the toolrest. This magnifies the the forces at the tools tip and makes it more difficult to control. Leverage is a wonderful thing when it's working in your favor. It's not if you extend your tool too far. If possible, move your toolrest inside the piece. (I suspect that this is what has been causing your catches.)
Consider using a hollowing tool with an arm brace or a captured or articulated system. Hollowing is, as a rule, end grain turning -- it's just done through a smallish opening. If you are reaching too far over the tool rest for regular tools, a hollowing tool may give you the ability to counter the magnified forces trying to rip the tool from your hands.
Of course, sharp tools, light cuts, and proper technique help, too.

[Scott Donley]

Sharp tools, light cuts,also if you are having to extend the tool from the rest, adjust the rest accordingly. Works for me. (most times :D )

[Burt Alcantara]

Bowl tools for hollowing are for experts only. Try s 3/8 or 1/2 spindle gouge with a medium sized round nose scraper. Perhaps, you should try making a few boxes then try a flared vessel much like an wide pilsner glass.

Personally, because of problems associated with hollowing, I bought the Monster articulated arm as has other members of this forum. It is very easy to use and you will not have UFOs.

Hollowing isn't easy nor is it intuitive. But it can be fun with the right tools.

Burt

[Jason Clark2]

Try drilling out as much as possible with forstner bits before you start hollowing. Hold the forstner bit in a jacobs chuck firmly seated in the tailstock and drill it out slowly, backing out the bit often to clear the chips. You may have a hard time finding a bit larger than 2" but even that is removing a bunch of material that you'd otherwise have to turn away. I will typically drill with a 3/4 - 1" bit before moving up to a 2 - 2 1/4".

Jason

[Jason Solodow]

[quote=Burt Alcantara;900596]Bowl tools for hollowing are for experts only. Try s 3/8 or 1/2 spindle gouge with a medium sized round nose scraper.

I disagree. I am be no means an expert, and I perfer to do my end grain hollowing with my 3/8 bowl gounge. I do have it ground with a fairly shallow bevel. I start off by using a 1/2-3/4 forstner bit in a jacob's chuck in the tailstock to get it down to the required depth. After that, it's all bowl gouge. Take light cuts and keep the edge sharp and it's a breeze. I finish off with my shear scraper and a light sanding.

[Richard Madison]

Brian,
At what depth are you trying to "hollow" when the trouble begins? I use a home made boring bar w/ 3/16" tool bit (amongst other stuff), and can cut with maybe 4-1/2" overhang before it gets tricky. Any distance that you can extend the toolrest into the opening will be helpful.

[Andrew Derhammer]

Bowl tools for hollowing are for experts only. I find this comment, no matter where it is used and for what technique or tool, to be absurd. Yes it may be harder, but you will only learn by trying.

[Craig Powers]

Just curious. What type of wood?

[Brian Brown]

My trouble usually starts about 1 3/4 - 2" in. I have been working with birch and poplar, which are some of the softer hardwoods. Sometimes softer is more difficult to work with. One of the birch pieces was torn out of the chuck, and the vase was cracked where the catch happened. Too bad, I was really happy with the form on the outside. :mad:

[Richard Madison]

Brian,
Should be able to go deeper than that w/ small bowl gouge w/ fingernail style grind. A straight conical grind gouge would be fairly easy to catch on the inside. Same for a scraper unless the tool rest is very close to the wood. Could you mock up a picture of damaged project and how it happened, showing the tool in approx. position when the catch occurred? Am sure I do not know the right answer, but someone here surely will.