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joe greiner
8th October 2008, 11:04 PM
In addition to the normal Show'n'Tell, our woodturning club has a "BringBack." At each meeting, there's a drawing from an envelope of member names, with absentees dropped back into the envelope. The winner of the draw gets the piece turned by the previous winner, who also provides timber for the challenge. The winner has two months to complete his/her work; thus, there's a staggered schedule of two works in progress. This is the entire set of rules.

I won the draw at our August meeting. I received a bowl and two pieces of cedar (originally one piece) from the previous winner. It wasn't quite clear what was sought from the two blanks. Was I expected to make two of something? Or was one of the blanks for practise and mistakes? I thought better than to ask, and took my cue from the movie, "Butch Cassidy and the Sundance Kid." In one sequence, one of the heroes is about to conduct a knife fight. He pauses to establish the rules, and promptly asserts "In a knife fight, there ain't no rules," while delivering a boot to the opponent's groin. Sounded about right to me, so I made my own rules.

I turned both blanks to cylinders between centres, with tenons at both ends (to allow future selection). The offset strip of sapwood suggested a goblet with captive rings to accentuate its origin as a single piece of timber. I turned the outside of the rings and the outside of a tulip-shaped bowl; the inward surface of the tulip profile will accommodate the wheels of the steady rest. I completed the rings and freed them from the blank, leaving a stout stem to serve as a sanding drum for the inside of the rings. Then I mounted the blank in a chuck with tailstock assist, and sanded the outside of the bowl. With support of the steady rest, I hollowed the inside of the bowl.

I removed the steady rest, and added a DIY pressure pad at the live centre to engage the bottom of the bowl. The pressure pad is simply a jumbo LEGO(tm) block with a piece of foam padding. The hole in the bottom of the block fits nicely on the cone of the live centre. I re-sanded the outside of the bowl to remove the wheel prints. Then I reduced the stem to more pleasing proportions. Intermittently, I taped the rings to the bowl or the foot to access different parts of the stem; I never had a full view of the whole stem. I suppose it could have been made more slender, but I didn't want to push my luck at this late stage. I waxed everything, at speed for most of it, but by hand for the rings.

The easiest way I've found for completing the bottom of pieces like this, is to drive a parting tool at an angle near the chuck jaws, forming a foot ring along the way. I also like to introduce a wee outboard step at the foot ring for some finesse. There isn't enough control space for additional goodies. When I've reduced the supporting timber to about 3 or 4 mm diameter, I just break the piece loose and touch up the bottom with a utility knife.

This is one of my most successful projects with captive rings. The rings flop just about right with respect to the stem and the foot. Cedar can sometimes exhibit ill behaviour. The provider of this driftwood opined that salt water content might have made it a more orderly candidate.

Dimensions (from memory, alas): 3" (75mm) diameter; 6" (150mm) high; wall thickness about 1/8" (3mm).

Some of the pictures are exaggerated stereo pairs (PnL/R), artificially induced by rotating the goblet. They can be free-viewed as adjacent thumbnails; as blowups, use reduced windows and set the images at about 2.5" (60mm) on centres. This may, or may not, be successful. Take care to match the scales of the window dimensions, and bail out if you experience discomfort.

Comments (praise and/or condemnation) welcome.

Joe <2008_10_17/Goblet/P1L/R,P2L/R, P4L/R,P6-9

Ed Reiss
8th October 2008, 11:35 PM
Nicely done Joe:2tsup:

Ad de Crom
9th October 2008, 12:14 AM
Joe, you explaned everything very well of your way of working, thanks.
I like it a lot.
It's a long time ago I turned a goblet, but I learned it from Marshall Gorrow, who told me to turn first the inside of the goblet, than the outside of the goblet and next the stem (step by step) and the foot, turning the stem with the help of tissues in the inside of the goblet and supported by the tailstock, so the inside of the goblet is filled with tissues, so his approach is different. Never turned captured rings, miss the tools for doing that.
Anyway it was good to see a beautiful turning from you.
Keep em going huh.
Ad :2tsup:

robutacion
9th October 2008, 12:20 AM
As you know (Challenge I) I like goblets, and this one of yours would had complicated things for the judges:doh:.
I most like the timber markings (I called it 2 eyes). I'm not so sure about the design on 2 specific areas, one is the stem, which is no doubt in within very safe thickness, but I think you would have no difficulty in slim it a fair bit. The other area is quite confusing, which is the shape of the coup, appearing to have the same outside shape and size in all pics apart from one, No 7, which looks more the shape and dimensions I would prefer, there is, in a conical configuration with the bottom half coup a little smaller than the top one, but in scale to each other, if you know what I mean.
The rings are very well made, and I reckon this goblet treated with some hard varnish (clear floor type), would be just the right size of goblet to "gobble" a few nice drinks from it, yeah :cheers2:
The only reason why I'm given you my opinion of how I see it, is not because is anything wrong with it, by the contrary, but only because I know you will not take offence and see it as simply someonelse suggestions or ideas of the piece you presented. You will agree, is always a certain level of concern and risk by doing it, and I'm particularly scepical in doing so.

Well, that's my 2 bob for now...!

Cheers:2tsup:
RBTCO

Skew ChiDAMN!!
9th October 2008, 02:11 AM
Cedar? You're a braver man than I to turn a goblet from that.

I can't say I'm overly rapt with the form, but I like your reasoning behind it. The sapwood really does enhance the fact that the rings et al came from one piece. :2tsup:

Goblets are my "thing" (most people turn bowls to relax; I turn goblets. :shrug: ) and I do it similar to the way Ad mentions, except I don't use a tailstock. Once I start on the stem I support the base of the bowl with my fingers. There's more than one way to make a cat into moccasins, eh? :D

Skaol!

joe greiner
9th October 2008, 03:35 AM
Thanks for ALL comments, mates.

Not excuses, just the way it was:

I did it barse ackwards, because I figured the rings would be easiest to stuff up, wanted them successful first. I don't use special scrapers on the rings, mostly a small dental pick to roll around the interior from both sides until it breaks loose; this is why they're not quite the same size, and also why interior sanding is more necessary.

The final shape came from no more than a lapse in conscience, RBTCO. You're right: a smaller lower part of the bowl would be more handsome. And what more can I say about the stem, except admit too much caution.

Time ran out for more attention to the finish. I took about two weeks overall, completed it Monday arvo, had a meeting to attend that evening, and Tuesday was a full schedule before the WT gathering. Even with that, I'm a few days behind on reading the newspapers. And the political BS in the upover is reaching crisis proportions.

Cedar isn't the best timber for goblets, especially with captive rings. I took the luck of initial success as authorization to continue. Perhaps soaking in brine might help for others? (To mimic the driftwood).

Joe

Gil Jones
9th October 2008, 07:10 AM
Nice work, Joe, I bet it smells good in your shop.

tea lady
9th October 2008, 09:27 AM
Nice little goblet. Is good to see how an idea has been carried through.:cool:

Logo block stolen from toybox.:2tsup:

I also like the stereo viewed images. they even work.:cool: (No ill effects yet.:unsure: ) Can I steal that idea?:D

hughie
9th October 2008, 11:26 AM
.

Even with that, I'm a few days behind on reading the newspapers. And the political BS in the upover is reaching crisis proportions.



understatement of the year......:U... ooley dooley :o :C :~ :U



Cedar isn't the best timber for goblets, especially with captive rings. I took the luck of initial success as authorization to continue. Perhaps soaking in brine might help for others? (To mimic the driftwood).



I agree, but all in all it has turned out well. But the up side is that if you can turn cedar in to goblets then your techinique has gotta be on the up and up :2tsup:

OGYT
9th October 2008, 04:39 PM
Quote: Even with that, I'm a few days behind on reading the newspapers. And the political BS in the upover is reaching crisis proportions.
I hear, in the lower-lying areas, many have perished amid the stench! :(

joe greiner
9th October 2008, 09:51 PM
I also like the stereo viewed images. they even work.:cool: (No ill effects yet.:unsure: ) Can I steal that idea?:D

Please do, TL. I wasn't too careful about the rotation angles, and some of them didn't look quite right. Might work better with smaller increments, and then choose a "best" pair. I started doing this sort of photography about 25 years ago, mostly on airplane flights. One of the best was flying back to Seattle from Anchorage, with a few seconds between Left and Right pics - from Puget Sound to Bellevue looked like a train set almost. For large-scale stereo, ordinary stereo cameras don't have enough eyeball separation, so a longer baseline is needed. Maximum range for normal eyeball centres (2.5" / 60mm) is about 1000 feet (~305m). For "enlargement" of small objects, closer than 60mm offset works a little better I think.

Too true, Al.

Joe

tea lady
9th October 2008, 09:55 PM
Please do, TL. I wasn't too careful about the rotation angles, and some of them didn't look quite right. Might work better with smaller increments, and then choose a "best" pair. I started doing this sort of photography about 25 years ago, mostly on airplane flights. One of the best was flying back to Seattle from Anchorage, with a few seconds between Left and Right pics - from Puget Sound to Bellevue looked like a train set almost. For large-scale stereo, ordinary stereo cameras don't have enough eyeball separation, so a longer baseline is needed. Maximum range for normal eyeball centres (2.5" / 60mm) is about 1000 feet (~305m). For "enlargement" of small objects, closer than 60mm offset works a little better I think.

Too true, Al.

Joe
Cool!:2tsup: I guess a business card is too small.:hmm::rolleyes: Maybe my next exhibition invitation.:cool: