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GC
11th November 2002, 11:06 PM
I've just destroyed a redgum burl platter, when a gum vein caused it to split and throw itself off the lathe. Spewing, how about 4 hours (I turn slow) of work, to see it destroyed while sanding, Devastated. Not to mention the lack of opportunity to use Doorstops free jar of earwax.

I'm sure everyone has done something like this before, but would be interested in everyone's worst, 'almost finished and...' experience. If anything it will make me feel better.

GC

mn2tx
12th November 2002, 01:28 AM
I was turning a hat. Nearly all sanded and finished when It "blew up." Flew apart.#@@&&%%!!!!**! Nothing left but "potato chips" Aparently what hapened. The rim of the hat developed a crack and being the hat was as large as my lath would handle , the crack in the rim cought the lath bed . Fortunately I had a face shield on. Even broke a tool on the wall. Yes! I was turning way too fast.!!!!
Originally posted by GC:
I've just destroyed a redgum burl platter, when a gum vein caused it to split and throw itself off the lathe. Spewing, how about 4 hours (I turn slow) of work, to see it destroyed while sanding, Devastated. Not to mention the lack of opportunity to use Doorstops free jar of earwax.

I'm sure everyone has done something like this before, but would be interested in everyone's worst, 'almost finished and...' experience. If anything it will make me feel better.

GC

Kev Y.
12th November 2002, 08:01 PM
FAILURES!!, I always have failures!!..

But then I take solice from Richard Raffin.. he said, "If you have not had a failure your just NOT trying" or words to that effect.

in between the failures I do have some success..

biggest failure to-date.. well I think the Japaneese Maple blank that did not secure to the chuck and ended up bouncing off of my fore-head, (NO I was NOT wearing a face shield THEN!! I always do now) would have to be my best failure .

John Saxton
12th November 2002, 09:18 PM
Lateral thinking... as an old Armed Services quote...."One is not lost...One is merely misplaced" end of quote!

Cheers http://ubb.ubeaut.com.au/ubb/smile.gif

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Johnno

Cliff Rogers
12th November 2002, 10:15 PM
G'day.

Worse failure would have to be my first marriage... http://ubb.ubeaut.com.au/ubb/mad.gif

Next worst failure was catching a bit of
curly crotch grain in the stem of a tall
Qld Maple hollow form vase with a wide rim.
I was holding it by the foot in a chuck &
had finished hollowing it out & was just
trimming the stem a bit to refine the outside
shape & BLAMO-WACK-CRACK-FIRETRUCK. http://ubb.ubeaut.com.au/ubb/eek.gif
I lost the piece against the wall in front
of me & it bounced back over my head.
I BENT the 3/8 detail gouge I was using.
I broke the tool rest mount on the ShopSmith
lathe I was using at the time & then, bug'rit,
I broke the gouge trying to straighten it.

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Catchya,
Cliff

Sir Chiz
13th November 2002, 05:40 PM
G'day Folks.

I prefer the artistic terminology...
"Designs By Destruction" http://ubb.ubeaut.com.au/ubb/biggrin.gif

My second attempt at turning a bowl was actually coming out purdy good,(or so I thought at the time) http://ubb.ubeaut.com.au/ubb/wink.gif I had it all finished and was quite proud of myself.
All I had to do was remove it from the glue block and finish the bottom,well,the faceplate was jammed on the spindle so I grabbed the knockout bar,stuck it in the hole and gave it a good RAP!
The faceplate came loose,the knockout bar hit the bed sending it up almost to the ceiling..
well,I watched return to Earth in slow-motion as came down directly on my bowl!!!SMASH!!!

I haven't made a Walnut bowl since! http://ubb.ubeaut.com.au/ubb/biggrin.gif

I also have a nice collection of funnels.

Sir Chizalot.

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I Love The Smell Of Sawdust In The Morning,
It Smells Like....Victory!

GC
14th November 2002, 10:11 PM
Oh yes one of those funnel bowls. I have made one or two of those.

GC

mn2tx
15th November 2002, 12:49 PM
I have one of those "funnel" bowls in the making now. I rough turned an ash bowl. I have the inside too deep. When it is dry and I remount it to finish turn, if I turn off the spigot off I will have a funnel. ????What to do about that????. I will have all winter to figure it out.

DarrylF
8th December 2002, 08:19 AM
Oldish topic, but there you go...

Turned a nice 12" bowl Friday night out of Jacaranda. Got the whole thing finished, took it off the lathe and then noticed the base was REALLY thin in the middle - almost transparent, and definitely too weak to be used for anything. Gotta work out how to fix that. Thought about turning a disc & glueing it in the recess that the chuck was holding, but maybe just a couple of layers of CA glue will strengthen it. Dunno.

Yesterday I was taking the finishing cuts on the inside of a nice 9" Jacaranda bowl and I THOUGHT I was being careful about depth. Managed to cut through the base - has a nice 1" dia hole in the bottom now. Figure I'll drop it into the bowl jaws and turn the base flat, glue a contrasting block on the bottom and turn a new base out of that. Worth a shot I guess.

Apart from those two, worst I've done is had a catch and split the base off the chuck - usually only one side, but often not worth fixing. Screwed two nice bowls that way, and nearly killed one yesterday. Fortunately it wasn't too bad a crack & didn't actually come off - so I reversed the bowl, glued up the cracks & turned the base true again. Came out pretty well considering.

ubeaut
8th December 2002, 08:58 AM
Darryl - Try using the chuck in compression mode to hold the bowl rather than expansion mode. This way you won't go through the bottom so easily and won't lose it out of the chuck as easily. Not only that but you won't have that big, ugly, gaping crevas, in the bottom of the bowl that is needed for the expansion chuck.

Failures - Never had one.... Just a lot of lessons learned. So far, once learned never forgotten.

Cheers - Neil http://ubb.ubeaut.com.au/ubb/smile.gif

rsser
8th December 2002, 03:05 PM
Darryl,

I did the same with a Silky Oak platter, so I put it in the cole jaws, cut a clean hole in the bottom and then turned and fitted a redgum foot to it.

cheers,

Ern

Baz
8th December 2002, 08:52 PM
Darryl,
Next time try using a depth gauge before you take the centre out of the bowl. I use a drill bit glued into a handle with a peg on the drill bit to set the depth. Before hollowing the bowl set the depth gauge to allow the required thickness of the bottom of the bowl and with the lathe turning push the drill bit into the timber until the peg touches the timber. It also makes it a bit easier to hollow out the bowl as you don't have that core in the centre.
Cheers
Barry

DarrylF
8th December 2002, 10:19 PM
I think I need to get something other than the standard jaws for my Vicmarc to be holding a bowl in compression mode - too many ugly marks at the moment.

I managed to save the Jacaranda bowl. Turned the base flat, glued on a disc of jarrah and turned that to suit the profile in the bowl jaws, turned a recess, flipped it around and finished off the bowl. Looks great in profile - nice contrast in colours etc. The circle of jarrah in the centre on the inside doesn't look so hot though. Might try a deliberately laminated bowl sometime.

I also managed to save a grey gum bowl I broke the base off the other week. Dropped it into the bowl jaws, cleaned up the base, turned a new recess (deeper this time), and sorted it out. Came up nice. Timber was though - cracks all over the place. Gotta love Superglue http://ubb.ubeaut.com.au/ubb/smile.gif

Also had a near disaster with a nice 8" bowl out of Lancewood today. Doing the final cleanup inside with a curved scraper, really light finishing cuts and somehow I managed a huge catch. Broke a nice chunk out of the side, but thankfully it didn't shatter. Pushed the piece back in place, hit it with thin CA and finished it off. Another nice save http://ubb.ubeaut.com.au/ubb/smile.gif

Baz: Saw that trick in Richard Raffin's book. Saw far I've been measuring the roughing of the bowl fine, but I tend to get into trouble when I have a few catches around the base and have to cut more than I expected. Today I left a little more in the roughing, measured more often and that seemed to go better.

Ahh well, back to the grind tomorrow http://ubb.ubeaut.com.au/ubb/smile.gif

Red neck
9th December 2002, 12:36 AM
Darryl,

Try the step jaws for the Vicmarc chuck. They enable you to turn a foot of either 50, 75 or 90 mm to be held in compression mode with minimal damage. After turning the inside of the bowl, re-mount it with Cole jaws (Nova) or the Vicmarc equivalent and remove or re-shape the foot if you wish.

For small bowls with an internal diameter of 100 mm or slightly greater, you may mount the bowl over the outside of the step jaws instead of re-chucking with Cole jaws.

Available from Carb-a-tec for around fifty db.

RN

Tim the Timber Turner
9th December 2002, 09:01 AM
DarrylF Hi!!

A couple of points spring to mind.

1. I very seldom reverse chuck bowls. The foot can be finished the before reversing.

2. I agree with Neil regarding holding by compression. Much safer this way. The down-side to this, is that you realy need a collection of different jaw sizes.

3. When using in compression, the safest way is to consider the chuck to be one size only.
That is the foot should be cut to the size of the chuck when it is opened 3 or 4mm.
At this point the jaws form a perfect circle and you have maximum metal to wood contact. The result is a better grip and no jaw marking (in most timbers). A piece of kitchen paper between the foot and the jaws will help with the marking problem.

4. Make sure the depth of the foot is just short of the jaw depth. This will help support the bowl with the face of the jaws. A foot that is longer than the depth of the chuck is not as secure.

5. I find step jaws to be of limited use. Most times you have to compromise the design to use the inner steps.

6. The coles jaws I had, used a rubber plug to hold the bowl and I found this could flex and give, this would result in catches and dig-ins. The Vicmarc reversing jaws are much better as they use a shaped plastic piece to hold the bowl.

Hope this is of help

Cheers Tim


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Some days I turns thisaway, somedays I turns thataway and other days I don't give a stuff so I don't turn at all.

DarrylF
10th December 2002, 10:12 PM
Thanks guys, I'll keep the tips in mind.

I was in Canberra the last couple days, so I called into Carbatec down there. Good guys and really seem to know turning, which is definitely helpful.

I picked up a set of step jaws for my VM120, so I'll give a compression grip a try this weekend. Also have some boxes I want to make, so they'll come in handy there too.

I picked up a very chunky curved scraper, which should help with the finish cuts on bowls. I also picked up a very good quality shallow gouge and some good advice on regrinding my deep flute bowl gouges, and a different tecnique to try.

I really don't want to add up all I've spent on the tools, chucks, jaws and other bits - makes the price of the lathe look silly I'm sure.

A week and a half of work then 3 weeks off to play in the workshop - can't wait http://ubb.ubeaut.com.au/ubb/smile.gif