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View Full Version : Can I salvage this little project?



Chris Merriam
05-27-2010, 10:22 PM
Still a newbie turner, I've only turned 6-7 small bowls. Thought I would try to make a little squat goblet, just 6in. or so tall, with a short fat bowl, a little neck, and a fairly large base.

Turned my cylinder round, then hollowed out the inside of the bowl. Was then working on shaping the outside of the bowl, and was going to match it to the interior shape. Unfortunately I had a nice catch, up near the lip of the bowl, and the gouge went through the lip, taking a chunk, and leaving a 3/4in. long crack.

I'm self-taught and tend to be VERY conservative around the lathe, so I'm wondering if I should attempt to salvage this thing. Can I spin it with the crack and reduce the height of the bowl to get rid of the missing chunk? The cracked area feels pretty strong, but I can wiggle it slightly with a firm amount of force.

Any tips on proper tool use at this point of a goblet? I was using a bowl gouge and was starting about 3/8in. below the lip and moving towards the base when it happened. I was alternating with using an EWT finishing gouge, but struggled with the round shape of the cutter down near the (soon to be) neck area.

here's some pics of the happy event. Any tips or guidance appreciated!!

Gary Conklin
05-27-2010, 10:29 PM
First tip, shape the outside before you hollow, never go the other way. Second tip: Life is to short to turn bad wood. Turning this at the point would be a BAD idea.

David DeCristoforo
05-27-2010, 10:39 PM
Scratch the goblet idea. Start thinking Champagne glass...

Gary is correct in that you want to shape the outside first. Then take the center out.

Chris Merriam
05-27-2010, 10:41 PM
Thanks Gary, for some reason I thought when doing a goblet that you hollowed first, then did the outside, but on further thought, in my case, probably would have been much better to start outside first. Maybe leave the neck area extra wide for support then shave it down later when I get to the base.

Point taken on the crack. Like I said, I'm self-taught, so I really didn't know if there is an 'acceptable' crack or not. Definitely not looking to take any risks with this. Was mostly just for learning experience anyways.

Thanks!

Steve Schlumpf
05-28-2010, 12:12 AM
Chris - at least you didn't launch it! Hard to tell how far the stress crack runs - so to be safe - set it aside and turn another piece of wood.

Easy way to think about the order of hollowing - how do you know how much wood to remove from the inside - if the outside hasn't been formed yet?

You shape the outside first - plenty of wood there for support of the cuts. Then you hollow out the inside - hollowing from the left edge and cutting towards the center. You can feel for thickness with your fingers or measure with calipers to insure your walls are consistent.

Once the bowl is finished - then move on to the pedestal portion - and do not go back to the goblet/bowl area again except to lightly sand.

Good luck with your next turning!

Chris Merriam
05-28-2010, 12:36 AM
Thanks guys, I will try again tomorrow!

Thom Sturgill
05-28-2010, 7:05 AM
I get to be the contrarian here. Here's a video (http://www.youtube.com/watch?v=FXNNbS4wC6w) on turning a goblet, and like you said, you start with the inside after rounding the wood. (of course that IS the outside of the upper portion and you do not want to shape the outside bottom of the bowl until the inside is done. That said, yours looks more like a bowl in size and proportions, but again you would want to keep as much wood as you can to steady the bowl while cutting.

Dont toss the piece, set it on a shelf for a while (years?) if the fracture does not open up worse it might be stabilized with CA or epoxy and you will have become more comfortable around the lathe.

John Keeton
05-28-2010, 8:07 AM
Chris, all good comments so far, and I would add that in looking at the pics it would appear you are taking aggressive cuts. I could be wrong, but the cut pattern would appear that way. Along with the flex of the rim from hollowing first, that could have contributed to the catch. I have also found that I have fewer catches when I keep the speed up a little - though if you get one, the effects are more dramatic!!

Dennis Ford
05-28-2010, 9:20 AM
Chris;
I hollow the inside of a goblet before doing the outside (like you did). This is backwards from my normal bowl procedure but the extra wood on the outside adds a lot of stiffness and makes the hollowing easier.

When you get a catch like that, learn from it and then start another piece. Trying to salvage the piece is more trouble than its worth. Unlike money, wood does grow on trees!

Chris Merriam
05-28-2010, 9:29 AM
Thom, I went the reverse method based on a website I found. Apparently I was too hasty in reading it though. They had a diagram showing the numbered cuts, starting with the inside, then stem, then neck, then base. What I failed to read was the text above the picture, which said turn the outside most of the way first!

I know it doesn't really look like a true goblet, was really just going to be a small bowl on a stem, just wanted to do something different with the few pieces of wood I have.

John, point taken on the cut depth. The grooves you see are actually from my poor cutting technique :) I have a really hard time cutting curves in one fluid cut, lot of stopping and restarting in the middle of the cut. I was spinning the piece at 1200 rpm, never really go above that speed.

Karl Card
05-28-2010, 9:36 AM
you know there is a word that we never say much but how many of us have made rockets? out of wood, that launch very well...lol

Just wait till you get a big ole chunk go past your head, I had an 8 inch piece of persimmon go past mine recently... makes you think about how you stand etc...

Like others have said, keep it, look at it often for reminders, then fix and finish and show...

Ernie Nyvall
05-28-2010, 12:52 PM
John, point taken on the cut depth. The grooves you see are actually from my poor cutting technique :) I have a really hard time cutting curves in one fluid cut, lot of stopping and restarting in the middle of the cut. I was spinning the piece at 1200 rpm, never really go above that speed.

Chris, I had the same take as John. I'm still thinking that what you are calling "poor cutting technique" may be the aggressiveness of the cut which may not be intentional, but just the angle you are presenting the gouge that makes it cut in an aggressive manner. I'll get those kind of grooves when starting a larger form in green wood, and watch the ribbons fly, but my gouge is presented at an angle that automatically takes aggressive cuts without much pressure. You are self taught, so I take it you haven't looked at any videos. A library has been started here and I think Bill Grumbine's video is in the selection, or you can purchase one for a longer look. You will see several different methods for presenting the gouge from taking off 1/4" in one pass down to almost dust coming off. Meanwhile, take a scrap piece of wood, and with proper face and head protection, try different angles of presentation with the gouge, making sure that the bevel of the gouge is riding the wood at any of the angles. The cuts on this project almost look like you're holding the flute of the gouge straight up or almost that way which would also explain why it would make it hard to cut "curves in one fluid cut". That flute can be presented from straight up to all the way on it's side, and then sometimes turned over. The handle of the gouge can be straight out and to the side to straight down.

Anyway, the videos(and/or a turning club near you) are worth a look, and from there you will find yourself figuring out new techniques, and making little tools with different grinds.

Too bad about the crack, but right off the bat you chose a nice piece of wood with good grain orientation to show it off IMO. Sorry for the long response.

Chris Merriam
05-28-2010, 10:14 PM
Thanks Ernie, I guess you and John have me outnumbered on taking aggressive cuts :) so I'll definitely need to reconsider my technique!

I do have two books, one by Raffan, and I have his DVD too, and every time I go to woodcraft I'm always very interested in their gouge orientation.

The flute definitely was not straight up, I never cut like that. I always start with gouge on its side, rub the bevel, drop handle to try to get 45 degrees, then roll handle to try to cut at 10-11 o'clock (when moving left).

I do have this perception that I need to have nice curly shavings, and that dust is a bad sign. I was amazed when I watched my DVD and saw Raffan just plow through a cut and a stream of shavings shot out. Perhaps I need to lower my standards!

Thanks for all the tips! Will attack a new bowl this weekend.