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A close friend asked me to make him a companion urn for him and his wife. He gave me the wood he wants it made out of. Segmented walnut burl he had sawn 15 years ago. He is a flatwood man himself. He says he wants it to be 400 to 450 cubic inches. How do I do the math for this. Math is not one of my stronger suits.
He is very exacting in his requirements right down to the shaping and finish. He is that close of a friend I will do my darndest to get it precisely to what he wants.
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11-12-2017, 10:08 AM
(This post was last modified: 11-12-2017, 10:10 AM by Angus.)
I hate making urns, in my opinion it's the most important job a turner can do. The simple part of the math is one cubic inch per pound of body weight. Figuring out the cubic inch capacity of a turned and non-cylindrical shape is where I run into problems so I cheat. In your case I would do a google search for companion urns, find something close to the shape he wants and size and go from there.
Just as an example this might get you in the ballpark.
https://www.inthelighturns.com/celtic-cr...eries.html
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11-12-2017, 10:36 AM
(This post was last modified: 11-12-2017, 10:39 AM by Woodshop.)
(11-12-2017, 09:39 AM)gear jammer Wrote: A close friend asked me to make him a companion urn for him and his wife. He gave me the wood he wants it made out of. Segmented walnut burl he had sawn 15 years ago. He is a flatwood man himself. He says he wants it to be 400 to 450 cubic inches. How do I do the math for this. Math is not one of my stronger suits.
He is very exacting in his requirements right down to the shaping and finish. He is that close of a friend I will do my darndest to get it precisely to what he wants.
use this
Cremation Urn Size Calculator
put in the numbers you know and convert it to cups use sand or what ever. knock together a scrap shape and pour it in, that should give you a good idea of size needed
looks like 31 cups, that's a big one.
HTH
Don
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11-12-2017, 10:40 AM
(This post was last modified: 11-13-2017, 06:04 PM by DaveR1.)
I was curious about what 400-450 cu. in. looks like so I knocked up a quick urn in SketchUp and developed the volume from it. This might not be the right shape but it gives an idea. You could draw the desired shape of the urn and quickly find the volume and check to see if the turned shape is pleasing at the same time. It's easy enough to create a pattern for the model, too.
![[Image: 37647870104_b26f1f46bd_z.jpg]](https://farm5.staticflickr.com/4533/37647870104_b26f1f46bd_z.jpg)
The volume is taken from the inside of the urn shape.
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(11-12-2017, 09:39 AM)gear jammer Wrote: A close friend asked me to make him a companion urn for him and his wife. He gave me the wood he wants it made out of. Segmented walnut burl he had sawn 15 years ago. He is a flatwood man himself. He says he wants it to be 400 to 450 cubic inches. How do I do the math for this. Math is not one of my stronger suits.
He is very exacting in his requirements right down to the shaping and finish. He is that close of a friend I will do my darndest to get it precisely to what he wants.
That is a huge Urn. Are both of them large people?
As of this time I am not teaching vets to turn. Also please do not send any items to me without prior notification. Thank You Everyone.
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The formula for figuring volume of a cylinder is (pi x radius) squared x height. Sorry, I couldn't figure out how to copy the equation onto the reply....
For a shaped urn, I usually use the (roughly) average diameter (between narrowest and widest diameters) and plug that into the formula. This has worked well for me in the past, but I was only looking for ~180 - ~200 cubic inches.
Remember, these are inside diameters.
Good luck!
Dave
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(11-13-2017, 05:48 PM)Big Dave Wrote: The formula for figuring volume of a cylinder is pi x (radius squared) x height. Sorry, I couldn't figure out how to copy the equation onto the reply....
fixt
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(11-14-2017, 02:20 AM)iclark Wrote: fixt
Thanks!
"One should respect public opinion insofar as is necessary to avoid starvation and keep out of prison, but anything that goes beyond this is voluntary submission to an unnecessary tyrany, and is likely to interfere with happiness in all kinds of ways."
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The urn is done. It measures 8.5 by 14. 16.5 to the top of the spindle. The segmenting was easy. The hard part was finding pieces of the burl that was stable enough for turning. I ran short so I still ended up using some padauk to add some high lights rings. The top of the urn I put in 3 inch pvc with threads and cut down and glue into the lid a matching cap so it screws on tight. Can't see it when closed together. I sanded the inside fairly smooth them used White latex to seal the inside. 8 coats of Poly on the outside. Looks good. Michael and Marilyn were quite pleased.
I have pics but I'm sorry no pics here. My slow internet makes it a long process and I feel it is Michael's and if he wants it shown he will do it he reads this site.
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(12-06-2017, 12:23 AM)gear jammer Wrote: I have pics but I'm sorry no pics here. My slow internet makes it a long process and I feel it is Michael's and if he wants it shown he will do it he reads this site.
I Would love to see it
,sounds really nice.
Life is what you make of it, change your thinking, change your life!
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