Most secure mounting for End Grain hollow form?

[Brian Kent]

I have a wet blank and a kiln-dried (glue-up) blank, each about 4x4x10". I am experimenting to see how large a hollow form pitcher I can turn. If I used the whole blanks, the narrow part of the neck is 4" from the top.

Please tell me if I am on track here:

I can put the dry blank between centers and turn a tenon. Then I can glue the tenon into a glue-block, screwed to a faceplate. I'll used a home-made steady rest while hollowing.

Is this possible using the green blank? Using super glue that is helped by a little moisture?

Am I on track?

[John Keeton]

Perhaps I am missing something. Why wouldn't you just chuck on the tenon?

[Brian Kent]

I can do that. I didn't know if that is too much for the Nova G3-D Midi chuck on the Delta lathe. 50mm jaws.

[Bruce Jones]

Why not use a 2" expansion tenon on each end turn the top & bottom first then glue them in the center; then put it back on and smooth it out and add details?

Bruce

[Faust M. Ruggiero]

Brian, Don't glue a block to end grain because it won't hold. Always start between centers since that gives you an opportunity to manipulate the piece to get the grain the way you want it. You can go to a faceplate after that and for a someone new to hollowing I believe a faceplate is a great option. Your chuck may hold well enough but the faceplate gives real security. Just plan on how to deal with the screw holes.
faust

[Brian Kent]

Yes, if I have a glue block I will glue a tenon in a recess to glue end grain. Screws in end grain can tear out of softer woods too.

[Reed Gray]

Glad you know to turn a recess in the glue block for end grain attachment as the end grain does not glue well. As for screws into end grain, if you screw them in at an angle, rather than straight in (called toe nailing when using nails) it does hold much better. Straight in line with the grain is like putting splitting wedges into the wood. Depending on the wood, predrilling may be required. I don't know metric measures, but I am thinking that is a smaller chuck. You may be able to get away with turning by tenon attachment only if you have a larger set of jaws to use on the chuck. A steady rest would help a lot when turning out the inside if you don't have a bigger chuck. Not as good as having a big heavy chuck for the same job, but manageable. You do have to be a bit more dainty when hollowing. CA glue will stick to wet wood, but I never trust it, though many do use it.

robo hippy

[Dennis Ford]

I prefer faceplate mounting any time there is a question about whether a chuck will hold. Screws don't hold as well in endgrain so I use longer screws and lots of them if the wood is soft, not really a big concern in the harder woods.

[Thomas Canfield]

You said that you are planning to use a steady rest which should give you stability while hollowing. I recently turned a 5"D x 8" H Norfolk Island Pine piece that I just held in #3 jaws on Talon chuck and used a steady rest when hollowing down to about 1/8" wall, and then used a jam arrangement to turn off the bottom. I think a lot depends on the uniformity of material, hardness, voids, and type of hollowing tools used. I did use blue painters tape under steady wheels to prevent damage to area under the wheels.

[Scott Hackler]

A standard tenon IS the prefered method of holding end grain. There is zero chance of ripping the tenon off and with the proper steady rest in place you can hollow as deep as you have the tool (or guts) to do. I have done several 14" tall vases with a tenon as the only hold point.

DO NOT do an expansion in end grain. The outward pressure can split the wood lengthwise, just like splitting firewood.

[robert baccus]

Several methods will work--screws do not hold well in green or endgrain. CA glue loves both-I use it on vases to 100+ #'s. Screws and CA might even be better on a critical piece.

[John Keeton]

FWIW, nearly all of my work is hollowed, I have never used a faceplate for anything, and I have never used jaws greater than 50mm. However, it is critical to use good technique, a good steady and a properly formed tenon. On a piece the size you are turning, I fail to see any gain in gluing a tenon into a block. You would be gluing wet long grain into dry face grain and introducing a weak joint into the setup and gaining nothing but extra work. Just my thoughts.

[Thom Sturgill]

I tend to agree with Lyle Jamieson who says he always uses a faceplate to prevent vibration. I would use the faceplate and deal with the lost wood from the screws. While screws will pull out, you are more concerned with shear, so use heavy screws and plenty of them and long enough to hold. You at close to the length limits of the chuck jaws at12".

[Jim Seyfried]

Most of the time I use a tenon. I have also done as Lyle Jamieson suggests and used a faceplate. I have read where Lyle will use dowels inserted perpendicular to the end grain (a reasonable distance from the end) to give something for screws to grip to in weaker woods. I haven't tried that yet, but it might come in handy sometime.

[Dale Miner]

The tennon on the wet blank glued into a dry waste block will shrink away from the waste block as water transfers from the blank into the waste block, and the waste block will grow away from the blank when the water transfers. In short, the glue joint will be very short lived.

Chucking a tennon directly with a steady would be preferred method. The use of a steady rest makes using a smaller set of jaws do able.