My latest f#$*up

[dai sensei]

Black Locust burl bowl rough turned over 12 months ago and finish turned at the club on Wednesday ~200mm dia x ~200mm high x 5mm thick. Sanded to 1200 all over and it looked like it was polished :cool:. Found a dimple in the bottom as I left so decided to take it home to finish. Removed the dimple Ok, then removed the foot, but as I was doing a 50mm flat recess for branding BANG :o :cry4:.

Glued them together and gave it a quick coat of NCL, to give you an idea of what it was going to look like, although I was going to use oil. The coffee infill piece on the lip was never to be seen again :-

http://www.woodworkforums.com/attachment.php?attachmentid=338782&stc=1http://www.woodworkforums.com/attachment.php?attachmentid=338784&stc=1http://www.woodworkforums.com/attachment.php?attachmentid=338785&stc=1

[A Duke]

Hi,
Worth twice as much with those artistic cracks. Any one who argues tell them to make a copy.
:2tsup:
Regards

[fubar]

Bgggrrr

[CAG]

fubar: with a thread title like that and your name (which was the latest post when I initially wrote this), I thought you were introducing the birth of a new child. Wrong section of the Forum I guess.

Neil: a real shame about the bowl. These things always seem to happen right at the last moment.

[smiife]

Hi neil,
What a shame,, looks like a nice piece of timber too!:o

[chuck1]

Heart starting and heart breaking, were you using Cole jaws when it let go?
I had a smaller one explode while using the Cole jaws. And glued it pack together and use it as a shellac bowl.

[dai sensei]

...were you using Cole jaws when it let go?

Yeh, too small a gripping face, should have used the donut chuck, but it was the catch on a knot squaring off the face that did the damage

[artme]

Oh bother and oh blow!!!!:C:C:C

[Sawdust Maker]

leather laces and a few holes would become real arty

[JDarvall]

break your heart.

uno, I reakon plastic bowls are stronger. maybe should…naaah.

[Tim Creeper]

Hay Neil, if that don't melt you. It would have been such a nice piece. Why don't you cast it and return it; you know with opened cracks. Might be interesting.:rolleyes: I saw the first pick and thought "that looks like that Black Locust I'm trying to sell (same spalting)" Then I read a bit and it is Black Locust. Anyhow, commiserations buddy.

[dai sensei]

Yeh it was a shame, being only 5mm thick and no more tenon it is impossible to return. I'm not into hand sanding that much either, plus there are just too many cracks, so to me it would just look like crap.

I'm thinking of cutting it to see how consistent the 5mm is as it was done by feel.

[turnerted]

What a bummer.A great jigsaw puzzle now .
Ted

[mick59wests]

I would have cried
Mick

[powderpost]

Bad luck, I know that feeling only too well. Last time it happened to me it was a segmented bowl I had just spent three weeks building. Not pleasant.

Jim

[Mobyturns]

Neil, We have all done it. Keeps us grounded and humble to have the odd oops moment. :D Not good for the psyche blowing up a piece with a lot of prep work in it though. :(

Always good to do a post mortem of the event to see if there are any learning opportunities from a failure. Looking at the way the bowl has shattered is interesting. Most of the cracks are not on lines / planes of weakness - only one appears to follow an inclusion. So it appears impact damage after it left the lathe is the main culprit.

When I have a failure or when others fess up - I like to ask myself what could be changed that would prevent this?

Was speed a major factor? Operator error? Or the choice of setup to finish the bowl?

Is the brand of cole jaws i.e. the button shape partly responsible? Too much speed? Too eager with the cut i.e. relatively too aggressive given the tenuous grip on a small area of rim?

Then there is the where did it land / strike first and how did it get there?

When reversing a bowl I also like to ask questions of myself like, How likely is the chance of timber failure on the rim from the cole jaws gripping force? Given the form & shape of the rim and the design of the cole jaws buttons, can it move / wobble / come out of the chuck?

Maybe I'm simply too conservative, however I like to put in a little extra time to make sure a bowl will not launch. Mostly self preservation. Maybe to pragmatic. However to me it seems logical to spend a extra time to make sure the holding technique is secure. Less time overall to do that than start again from scratch or waste a good blank.

[dai sensei]

Yes lots of things to learn from our mistakes. Unfortunately CRAFT has set in well and truly and I had forgotten why I don't use those jaws anymore for this shape. You are right about the damage, it broke initially as it came loose, but as I was in the carport each piece broke again when they hit the concrete slab some 10 feet away :-. If I was in my workshop the nice 2 feet of sawdust/shavings on the floor would have protected it :U

[Paul39]

Neil,

I'm sorry you lost that one. Nice shape and figure. I'm happy you were not in the way of flying objects.

[Skew ChiDAMN!!]

>.< What can I say? Pity, it would've been a nice, well executed piece.

[Evanism]

Drill lots of small holes along the edges. Strip some electrical cable for the copper, lace them together and make a Frankenstein!

[Wood Nut]

Hi Neil,
Like the others, I agree that it is a real shame.

However, I would not be too quick to cut it in half or throw it away. Don't be too hasty in making your decision. I've been looking at it for a few fays and feel there are several ways to rescue the piece and let your artistic juices flow. Some methods have already been mentioned, such as laces and copper wire. You could also consider cutting in some butterflies etc. I'm sure you have a bit of resin on hand to fill/glue.

Have you considered cleaning the base and gluing on a sacrificial block (very accurately) to act as a temporary foot? Turners such as Vaughn Richmond often turn without chucks! (He did a demo using this method at last year's New Zealand Symposium).

Once glued/stabilsed/strengthened you could wrap tightly in glad wrap and then tap and use the tailstock for initial support of the sacrifical block before reversing.

Some carving away of unwanted areas and you could have a very artistic piece.

Don't give up yet.

Cheers,
Paul

[Lplates]

Glued them together and gave it a quick coat of NCL

Like the others i agree that the cracks have just added another dimension to the piece. Looks great!

Just a newbie question if you would indulge me....what is NCL? Sanding sealer?

Thanks
mat

[dai sensei]

NCL = Nitrocellulose Lacquer

[KBs PensNmore]

Sorry to hear that this happened to a lovely artistic piece. Why is it always happens, when it's nearly finished.:( Like others have commented, add some copper wire, it would look fantastic.:2tsup:
Hope the shoulder is getting better.
Kryn

[Mobyturns]

Sorry to hear that this happened to a lovely artistic piece. Why is it always happens, when it's nearly finished.:( Like others have commented, add some copper wire, it would look fantastic.:2tsup:
Hope the shoulder is getting better.
Kryn

Burn it and move on I reckon. Hide the evidence fast. :D

Natural defects look OK with a bit of spicing up. Shattered pieces always look like shattered pieces to me no matter what you do to them. On the other hand I have seen a turner who deliberately cuts sections from pieces to make collage wall hangings. Maybe if you get enough smashed bowls you could make one. Some of us would be waiting a while to build up a stock pile. :p

[dai sensei]

Natural defects look OK with a bit of spicing up. Shattered pieces always look like shattered pieces to me no matter what you do to them..

I agree

[powderpost]

This is a good opportunity to play with paints, dyes or gilding. Maybe even some coloured lacquer? Never know what can come out of it? Don't like wasting all that effort.

Jim