How do you mount a chalice?

[Brian Kent]

My chalice mounting attempts are not working. I have used a tenon in a chuck and even a threaded insert in an extended base. When I start to turn the inside, the forces throw it out of whack.

I have tried a bowl gouge, a scraper, and a spindle gouge.

The wood is dry white oak, which may not be a good way to start.

Any recommendations? Is it time to use a different wood and make a steady rest?

Brian

[Roger Chandler]

Holding in a chuck and support of a steady rest should do the trick for you Brian.........the length this is extending out of the chuck unsupported is a big problem [ like you don't already know that! :rolleyes:] You are on the right track.......just need some additional turning devices to complete what you are attempting!

Good for you on expanding your horizons so quickly.........you might try to settle on a form or two and get good at them, then expand to other forms until fairly good at executing them.......just a little pointer to help you get to the place you feel competent at what you are doing instead of jumping from place to place without being sure of the processes you tried once or twice already.

[paul vechart]

Brian...in the 1st photo it looks like the shoulder on the tenon could be larger to support the wood and prevent it from cocking to the side.

[Allan Ferguson]

It looks like you may be using a Nova chuck with a dovetail cut in your tenon. If so, you will not get a secure grip on the tenon. Cut your tenons straight with a larger shoulder, it will stabilize your turning. Try boring the opening with a large drill bit, then finish wit a scraper . Keep turning short in length. Allan

[Curt Fuller]

Brian...in the 1st photo it looks like the shoulder on the tenon could be larger to support the wood and prevent it from cocking to the side.
I'll second what Paul has said. The shoulder on the tenon should be at least wide enough for the front edge of the jaws to rest upon. That will give you the most secure grip. But, I also suggest drilling a hole in the cup end of the chalice before hollowing out the cup. Do you have a drill chuck on a morse taper that will go into you tail stock? If so, drill the hole (I like to use a 3/4" bit) and that will serve both as a depth gauge for hollowing the cup and as a starting point for the hollowing. Then when hollowing the cup on something not supported by the tailstock I like to use a very light cut, pulling from the bottom of the hole out towards the end. If using a scraper, don't rest it flat on the tool rest, turn it on about a 30 degree angle so you get more of a shearing cut. After you've done it a few times you'll get the feel for it and you can get a little more aggressive. But it takes a light touch. Also, I have much better luck if I shape the cup and hollow it before I work on the stem. The extra wood left by not turning the stem gives you better support and less chatter. On most any spindle work you do that isn't supported by the tailstock you'll have better results if you work down to finished product from right to left and don't try to go back out once the stem gets thin. That's usually when they break off.

This is an old post but the pictures might help explain some of my discombobulated words.
http://www.sawmillcreek.org/showthread.php?41497-Quickie-Demo-on-goblets-(page-1)&highlight=turn%20goblet

http://www.sawmillcreek.org/showthread.php?41519-Finished-Eucalyptus-Goblet-from-Demo

[Jamie Donaldson]

It appears that you are reducing the diameter of the stem before the cup is hollowed, and that allows too much flex and chatter. Shape the outside of the cup, then hollow before advancing the design any further down the stem toward the base.

[Thom Sturgill]

I turn a fair number of goblets. My procedure runs like so:

Mount block between centers and create tenon

Mount in chuck and true up cylinder with tail stock in place

Turn outside of bell only as far as bottom of inside or a little less - I like to have the mouth slightly smaller than the widest part of the bell and initially shape the outside only enough to define the shape - about 3/4 of the bells length.

Sand turned portion of bell to finish

Remove tail stock

(install steady rest and) hollow inside of bell and sand to finish

(remove steady rest)

Reinstall tail stock with large cone fitted to bell - I keep a few cutoffs from prior goblets that have enough wood to form a cone or dome. The center mark from where the original was mounted on centers allows me to put the tail stock to the center of this piece and support the bell.

Shape bottom of bell and start down stem, turning about 1" to finish at a time - if the support mentioned above is in use, I turn the entire length bell to base, then sand.

Turn and finish sand base and part off, slightly hollowing underside

Sand bottom using small 1" or 2" disk mounted in drill press checking flatness of edge against known flat surface. Its easy to get too agressive and damage the rim.

The steady rest is optional but recommended any time you are working further from the chuck than ~ 3x the diameter of the work piece where it is supported (tenon diameter) - so for a 2" dia tenon the piece should be supported if it extends more than about 6" from the chuck. YMMV, this is just my rule.

[Brian Brown]

Can't tell for sure what kind of chuck you are using, but if it is a Barracuda, or a CSUSA Apprentice chuck they are designed to be used with a straight sided tenon, and not a dovetail on the tenon. However, I find that a slight dovetail works better, especially with harder woods. The larger diameter portion of the dovetail should be toward the headstock, and the smaller toward the tailstock.

Also with any wood, especially hard stringy grained wood like oak or locust, you tools need to be sharp. Walking in a Detroit dark alley, mother in law coming to visit scary scary sharp. When they are very sharp, and they meet the slight resistance of a small catch, they are more likely to slice through the resistance, rather than to catch and be pulled into the wood, causing your work piece to jerk out of the chuck. When you sharpen your tools, a slight metal burr forms and curls away from the sharpening stone. With a scraper, that is usually good, but with other tools, that burr causes problems. Be ready to remove the burr with fine sandpaper. For a bowl gouge, after I sharpen, I wrap some 400 grit automotive sand paper around a dowel that is slightly smaller in diameter than the flute of my gouge (assuming that it is round). Just a few strokes starting from the handle end, and out through the tip removes the burr, and the tool cuts much better. Using the tool with the burr on will quickly remove the burr, and the edge left behind will be thicker and duller than if you use the sandpaper. Good luck, and let us know what works for you..

[Brian Kent]

Thank you, thank you, thank you and thank you, etc.

Everything you folks have said makes sense. Yes, it is a Nova chuck and yes, I have a drill chuck on a #2 morse taper.

And Roger, I agree about sticking with one thing before I move on. I ran out of bowl blanks in the shop so I wanted to do something, even if I did it badly :)

Brian

[Bernie Weishapl]

Brian I do quite a few of these. Once mounted in the chuck I mount the steady rest. I don't do any turning on the stem till the cup is hollowed. Like Jamie said it allows to much flexing.

[Michael Mills]

I agree with the others but will add that it appears you are using the 50m bowl jaws. You need the 35mm or 45mm spigot jaws which are made for endgrain holding with unsupported end. The bowl jaws are like holding a baseball bat with your finger tips, the spigot jaws are wrapping your hand around the bat.

[Brian Kent]

That's pretty interesting, Michael. I am looking those up.

[Thom Sturgill]

I agree with the others but will add that it appears you are using the 50m bowl jaws. You need the 35mm or 45mm spigot jaws which are made for endgrain holding with unsupported end. The bowl jaws are like holding a baseball bat with your finger tips, the spigot jaws are wrapping your hand around the bat.

Valid point. Bowl jaws are designed for maximum strength in expansion mode while spigot jaws are for compression. The 35 and 45mm jaws have the same ratings about 5"dia by 4" long in expansion and 6" dia by 10" length in compression. The 50mm jaws are rated for bowls 12"dia by 4" in expansion and only 6" dia. by 4" in compression. In either case a 6" chalice is over long for those jaws if not supported by either a tailstock or a steady. BTW the power grip jaws (Nova Titan Chuck only) are rated at 16x6 expansion and 8x12 compression.

[Brian Kent]

I found a piece of sycamore firewood that told me it should be a chalice. I told it, "I'm not making chalices right now. I am practicing bowls." It said, "But I am only firewood. If I am wrong and I end up in broken chunks, you can still use me for firewood." How could I argue?

So I used a faceplate with long screws, roughed off the pointy places, drilled down the center, turned the inside before outside, and did a bunch of other stuff you folks just taught me, and out popped a little 4" chalice.

Last photo is with WOP added.

[Jay Jolliffe]

Nice job Brian....I'm still on bowls & small plates....Haven't graduated to something else yet. Still learning...May have to try one of those.....

[Baxter Smith]

Looks great Brian! Turning whatever interests you at the moment is one of my favorite parts of woodturning. Completely mastering whatever you did before isn't possible anyway.:)

[Thomas Canfield]

It looks like a chalice. Nice job. Looking at the 4th picture at start of thread, it looks like you are trying to hollow the inside turning from the large dia to center. I was told that you always (or nearly always) wanted to turn "downhill" which means on cross grain turning inside from outer to inner and for end grain turning from inside to outside. I would recommend turning short goblets until you get the hollowing worked out and you are taking light cuts and pulling the pice out of the chuck. A small scraper works well after drilling a starter hole.

[Brian Kent]

You are right, Thomas. I was trying to go the same direction inside as if I was making a cross grain bowl. Thank you for the info.

[Kathy Marshall]

That turned out very nice Brian! Looks like you used all that advice to best advantage. Before long you won't even have to think about what you're doing, it will just be automatic.

[Thomas Canfield]

You are right, Thomas. I was trying to go the same direction inside as if I was making a cross grain bowl. Thank you for the info.

Brian,

Don't ask how I know. I have found that doing about 6 of a style for practice ahead of trying for a final also helps. It sure looks simple when someone is doing a demo on a long stem goblet, but that was the result of lots of practice.

[Brian Kent]

Applying a lot of advice here and some practice with that advice, I picked up the chowdered oak chalice and tried again.

First, I noticed that the screw mount had ways of registering in the chuck that I had not seen before. That made for a more secure mount.

Second, I mounted a forstner bit in the tailstock and drilled to depth. That took care of a lot of inside the cup stress.

Third, I started in the middle of the cup with a small round-nose scraper and drew it outward. Thank you Thomas Canfield for noticing I was treating it like a bowl orientation instead of a spindle orientation and was working against the grain.

Fourth, I brought the tailstock up to the cup opening with a piece of cloth between the casing of the live center and the top of the chalice. That made everything smooth and steady while I finished the work on the outside.

It was a laminated piece of oak that was just a test anyway, but very satisfying to get all of your help and make it work when I could not do that 12 days ago on my own. Thanks!

PS. Later purchase and project will be a spigot chuck and a steady rest.