# Is there any way to create a miracle?



## PTownSubbie (Mar 6, 2009)

Well, I was so close to finishing the segmented bowl below when I started hearing crackling in the center of the bottom. I stopped the lathe and my worst fears came true. The bottom is so thin that it is beginning to crack!!!

What a bummer!!!!

I stopped immediately and tried to put some CA glue on the crack in an attempt to salvage the bowl.

Is there any way to add strength to this area?

How does everyone else determine how thick the bottom is as you are working it in the donut jig?

Good thing it was only out of scrap and the only real cost was my time.....


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## AZ Termite (Dec 20, 2008)

You might try epoxy on the bottom side and see if you can build it back up some. As far as the jig goes, I have never used a donut jig before, but I always use the edge of the bottom piece as a guide. I try to leave the bottom about 3/8" thick so I don't have that problem. A lot of it is trial and error. Keep at it, it gets easier as you go along. Let us know how it turns out.


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## vcooney (Dec 21, 2008)

How about trimming the foot off and glue another piece on to it?
I use a depth gauge before I chuck the bowl to determine the thickness of the base and then measure the amount that I have taken off while trimming.


Vince


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## firehawkmph (Apr 26, 2008)

Ditto on what Vince said.
If that doesn't work, keep cutting and you have made a funnel. I have heard of this happening before......:laughing:
Mike Hawkins


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## Hhaines (Nov 26, 2008)

Purty bowl......nice design.........


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## b00kemdano (Feb 10, 2009)

Turn the bottom out and glue on another layer?


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## john lucas (Sep 18, 2007)

I would turn out the other bottom leaving a small rabbit. Then fit a new bottom in. If it's very large I would not use solid wood for this. Make up your own plywood out of several layers of solid wood layed cross grain to each other. That way wood movement won't break your bowl later on.
To find the bottom thickness use a square. Sit it on the bed of the lathe and place it against the bottom of the doughnut chuck. make a pencil mark on the bed of the lathe. Now measure the depth of the bowl. Transfer this measurement to the bed of the lathe. Add the thickness you want the bottom and the foot. Now after you mount the bowl just use the square to check and cut away material until you have the foot the right thickness.
Even easier use a lazer pointer mounted above the lathe. The most important part of any of this is to measure from the lip to the bottom of the bowl before putting it on the lathe.


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## PTownSubbie (Mar 6, 2009)

Well, thanks for all the input. I took a picture of the funnel just for you Mike.....:yes:

You can see the bottom on top of the bowl. The glue is showing through. I did part off the bottom and put a new one on. I haven't turned it yet but I probably will tomorrow.

I will let you all know how it works out.....

Just to make myself feel a bit better, I glued up another one to give another try......

Fred


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## Barry Ward (Mar 22, 2008)

*is there a way to create a miracle?*

Ditto on what has been said,been there done it a few times,bowls came out pretty nice.In fact I have another on waitin for a bottom. :yes:Good luck there :thumbsup:
Ken


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## firehawkmph (Apr 26, 2008)

Everytime something like this happens, it is a good learning experience. Almost everything can be fixed, or as we call it, ' a redesign'. Let us know how it turns out. Also these kind of things make for good stories when you are showing the piece to others. Thanks for the funnel pic.
Mike Hawkins


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## PTownSubbie (Mar 6, 2009)

*Thanks for the help!!*

Well, the title says it all. Thanks for the suggestions on how to fix my "redesign" :yes:. I parted the bottom and glued a new one back on. I must say it turned out pretty nice. I still have some sanding to do but the bottom is in tact with no holes.....:thumbsup:

I am so new to this that I would have never thought of parting off the bottom and putting a new one on.:laughing::laughing: What an great way to recover.....

I must say that getting that thing centered in the donut chuck took a -ton of time. I obsessed over it and even used my dial indicator to get it right.

A few coats of tongue oil and it will make a good salad or fruit bowl.:notworthy::notworthy::notworthy:

I'll post a final picture when it is all oil'd up.....


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## firehawkmph (Apr 26, 2008)

Pt,
Next time you go to recenter a bowl, try either marking the faceplate disc with a pencil before you take it out of the clamp. Or if you have already taken it out, measure the diameter of your bowl and with just the wooden disc that is mounted to the faceplate attached, move your toolrest out in front of it and use it to rest your pencil on. Measure from the center half the diameter and make your circle from that point. Just turn the disc by hand. At least you'll have a visual reference to set your bowl back into. Then when you clamp it, don't tighten it tight, just snug enough to hold the bowl. Turn it by hand and see if you have any runout. You can get the edge of your tool rest close and use it as a gauge. Find the high spots and tap it with a rubber mallet. Once it is running true, tighten and recheck one more time. I don't pull out a dial indicator for this. You should be able to get it close enough to make your repair this way. 
Mike Hawkins


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## ralphtaff (Feb 28, 2009)

PT,what size blocks for each layer of the 5 layers,and what size for the dark wood or short ones,and what degree do you cut the boards. i have never tried segmented bowls becaouse i do not know what sises and degrees to cut the boards my email is [email protected] hope to hear from you or some one on the sizes.I had or should say still have a shopsmith but i bought a Master Quality Tool lathe at a good price and wow the difference is amazing.


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## jdixon (Nov 21, 2007)

PTownSubbie said:


> Just to make myself feel a bit better, I glued up another one to give another try......


That's what I like to hear! Jump right back on that horse and go!:thumbsup:

Nice save on the bottom. Looks like it will turn out great. Can't wait to see the one you just glued up. It looks like it will be very nice.

John


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## PTownSubbie (Mar 6, 2009)

Ralph,

All the segments are ripped to 1-1/2" wide and length of the bottom ring is about 2" on the long side. You can make the sizes whatever you want. The biggest thing is that you want to determine how large you want the bowl to be. Each ring segment is 1/4" longer than the one below it. This seemed to work out well and gave the bowl a decent profile. So, determine how big you want the bowl to be and start from there. Starting with the 2" segments and placing 5 rings in a sandwich, the bowl ended up being about 11.5" wide on top and about 4" tall.
The small pieces in between each segment are 1/2" wide. These are not needed but they definately add to the bowl's looks.

The key is making sure you have accurate miter cuts. There can be no gaps on the miters or you will have gaps in your finished bowl. This means you have to get an accurate miter setup. Some have opted for an expensive miter gage but I went less expensive and purchased a device called the "miterset". This cost me ~$35 vice $150 for a new miter. I use the original miter gage that came with my table saw and use the miterset to get an accurate angle.

You determine the angle based on the number of sides you want to use. I used 8 sides. You determine the miter angle by taking "360 degrees / (2*# of sides)". My miters ended up being 22.5 degrees.

I will send you a group of pictures that shows the entire process. I will put it in a PDF format.

Good luck!!

Fred


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## Barry Ward (Mar 22, 2008)

*Is there a way to create a mitacle?*

When I made my donut chuck,I drew circles around the base about 1/4" apart and it really helps lining up the piece.


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## PTownSubbie (Mar 6, 2009)

I drew circles on the original piece of plywood but it was not running true on the lathe which caused wobble. So, I tried to face the plywood the best I could. Of course, this removed most of the circles....

I need to put them back on again.....

Boy did I learn a bunch on this project!!!!:yes:


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## b00kemdano (Feb 10, 2009)

Looks great! Nice recovery. 



> You determine the angle based on the number of sides you want to use. I used 8 sides. You determine the miter angle by taking "360 degrees / (2*# of sides)". My miters ended up being 22.5 degrees.


I was thinking about this today while I was mowing my lawn... Wouldn't it just be "360 / # of joints" ? The blanks that you are gluing in the pictures actually have 16 sides, thus, 16 joints. I only mention this because as one who is not mathematically inclined, I prefer to use the simplest formula possible.


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## PTownSubbie (Mar 6, 2009)

Yep. It is the same if that is how you want to think about it.

8 segments or 16 sides (each segment has 2 sides) Thats why I multiply the segments by 2 in the denominator.


If you want to count the sides, then take 360/# sides.

If you want to only count the segments, take 360/(2 * # of segments).


I got it now. I should have said segments in the prior post instead of sides......

Hope that makes sense.

Fred


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## phinds (Mar 25, 2009)

The woodsman said:


> When I made my donut chuck,I drew circles around the base about 1/4" apart and it really helps lining up the piece.


 
What I recommend is actually scribing the circles in the base of the donut --- instead of using a pencil, make them 1/16 or so deep with a light touch of skew chisel or the edge of a parting gouge. That way if/when you have to clear up the face of the base, your circles don't go away.


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## PTownSubbie (Mar 6, 2009)

Good point. Scribe over pencil..... Again, something I didn't even think about.....

I guess that is why this place is here.....:laughing:


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## PTownSubbie (Mar 6, 2009)

*Finally finished*

It is finally done. I learned so much from all you guys. Thanks for the inputs.

Overall, it is about 11.5" in diameter by about 4.5" tall. It is finished in tung oil so that it can be used with food.

AZ Termite. Thanks for the inspiration on making this. It was your bowl that inspired me to give this a shot. 

It is not as difficult as you think to do this. Everyone should give it a shot.

What do you think of the bowl?


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## AZ Termite (Dec 20, 2008)

Pt, that bowl turned out great. Keep up the good work. I have had a lot of fun with the bowls I have done. I am glad I was an inspiration to you. As I am sure you know now its not as hard as it looks. The cool thing is your options are endless, and take you as far as your imagination will.


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## b00kemdano (Feb 10, 2009)

Nice bowl! I can't wait to finish up some other projects and try a segmented bowl.


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## PTownSubbie (Mar 6, 2009)

*The saga never ends!!!*

Well, as a proud woodworker I took my finished bowl to work today. Everyone liked it but when one of them went to remove it from the shelf it was sitting on, the worst thing that could have happened did.

He dropped it. My fears of the top section being too thin was true. It didn't last the fall!!! The top shattered like glass.:blink: Boy did he feel really really bad about it.

I "redesigned" it by parting off the top ring plus a little more. Now it is much stronger and it still looks pretty good. I had to be creative on how to put it on the lathe though. Something that wasn't very difficult but since I hadn't done it before, it was something new.....

Boy, I continue to learn and learn.:thumbsup:

Fred


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## slatron25 (Dec 18, 2007)

Nice save, again. And nice bowl. You could write a book on this bowl now.:thumbsup:


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## phinds (Mar 25, 2009)

*movement in service?*

I'll be very interested in hearing by the end of this summer, whether or not you've experienced any cracking in the bowl due to movement in service. I've always hesitated to do segmented bowls as big and thin as this one because of that potential problem.


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## Hokie-G (Mar 28, 2009)

*9 Lives*

This bowl must be a cat! It has 9 lives! And, it looks like it was designed this way from the start. Great Job. 

The true measure of a woodworker is his ability to make his mistakes look intentional (or not be seen at all!)


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## don716 (Mar 1, 2008)

You must be proud of that bowl.You and it have been through alot together.Great save.
Donny


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