# Making wooden bucket



## wmodavis (Aug 28, 2007)

I have a need to make a tapered wooden bucket and am wondering if anyone within earshot has a straightforward way to determine the compound angles for the staves. Any suggestions would be appreciated.


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## GaryK (Jun 25, 2007)

The angle should be 360 divided by the number of staves divided by 2.

20 staves should then be 9 degrees.

The taper of the staves depends on the taper of your bucket.


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## ChicoWoodnut (Dec 15, 2007)

I think the guys who make buckets do it more by eye than calulator. I saw Roy Underhill do it once. He just used froe, a spokeshave and some iron rings. He had some kind of tool fo making a slot for the bottom to fit into. I found this website. I'll bet there are more.

Update: The tool for the slot is called a Croze.


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## swied (Feb 6, 2008)

You don't need to worry about calculating angles if you use a router with a bead and cove bit.

http://www.rockler.com/product.cfm?page=18920&filter=bead%20and%20cove

The 3/8 radius bit is probably the one you would need for a bucket. Then again… at $82.99 you would have to make a lot of buckets to make it worth while.


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## North40 (Oct 17, 2007)

GaryK's method for calculating the angles for bucket staves will work out close enough as long as there isn't too much slope on the sides of the bucket. However, as the slope of the bucket sides approaches a bowl shape, the angle of the bevel on the sides of the staves will decrease, reaching a zero angle when the bucket becomes a platter!

I proved this first hand when I made my lamp shades - which are like four-sided buckets.

(my first use of a project card! yay!)

I thought and thought about how to calculate the joints and finally decided the mating angles must be 45 degrees - as GaryK's formula indicates. Fortunately I dry-fit the sides, but my lamp shades looked like an M.C. Escher drawing! From there I "snuck up" on the angles until they fit right.

I think you could calculate the angle of the bevel using GaryK's formula, and call that measure angle "b". Divide "b" by 90 to get the bevel deviation "d". For every degree of slope "s" (the angle that your staves are off of vertical), you would subtract that much "d". a=b-(d*s). For 20 staves D=1/10, so for every degree of slope you would deduct 1/10 degree from the bevel.

I think the real trick will be figuring the taper for each stave to create the desired slope. I'm not entirely sure how to figure that. This is where I turn to AutoCAD!


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## tenontim (Feb 24, 2008)

This is why the old timers used a draw knife and did it by eye.


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## North40 (Oct 17, 2007)

No kidding Tim! I was just thinking about a coopered barrel. The staves have curved edges. Can you imagine the calculations that would go into that?


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## ronstar (Mar 29, 2008)

The chord of a segment of a curve =2 times radius times sin (central angle /2)
Say the bucket top is 16" inside diameter with 12 staves
A circle is 360 degrees, so the central angle for each stave is 30 degrees (360/20)
The radius is 8" or half the 16" inside diameter.
So, the inside measurement of each stave top is 2 times 8 times sin (30/2) = 4.14" 
Say the bucket bottom is 12" inside diameter. The central angle is still 30 degrees. 
The inside measurement of each stave bottom is 2 times 6 times sin (30/2) = 3.11"

The stave angle is half the central angle or 15 degrees for 12 staves. 
Hope this helps.


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## wmodavis (Aug 28, 2007)

Think I'm going to get out my pencil and 'Draw me a Knife'. No fooling guys thanks a lot. This is all very helpful. Especially 'ronstar' that's exactly what I was looking for.


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## North40 (Oct 17, 2007)

Ron - of course! I'm over here trying to figure out the angle of the taper, but all you need is the width at each end of the stave.


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## fredf (Mar 29, 2008)

Peter O has a good point as you increase the angle of the sides, the miter angle required increases

to calculate compound miters check out http://home.earthlink.net/~timcera/angle.html


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## cebfish (Jan 15, 2011)

there is good way i learned from a book foxfire 3 take two 1x lay side by side connect on end with a peice of leather from that end mark the dia. you want spread open that will give you the angle no math needed


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## Loren (May 30, 2008)

I used to build conga drums. That's how I got into woodworking.

Early on I used trial and error to find the angles. I made blocks
for reference for 12, 16, 20 and 24 sided cylinders. When you
make the cylinder tapered (conical) it affects the geometry of the
side joints a little. Practical trigonometry.

Later I had a machinest make me a dial indicator mount which allowed
me to repeat angles very precisely using trig. This was before the
magnetic doo-dad came out which sticks to the side of your blade,
zeros to 90 degrees, and then uses a level inside to calculate the
blade angle.

Anyway, setting the angle precisely is juts half the battle. Knowing the
correct angle in the first place is the other. If your bucket is almost
a straight cylinder you can ignore (or fudge) the change introduced
by the conical form.

Later I got an angle gauge from Veritas which made set-ups for small,
12-sided forms easier.


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## canadianchips (Mar 12, 2010)

http://charlesneilwoodworking.com/
This guy has a video on building buckets. Its well worth watching.


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## Finn (May 26, 2010)

I have made wooden buckets and wooden vases and using a taper jig and keeping the flare under 5º will allow you to ignore any adjustment on the angle to make the 360º bucket. I usualy use 18º on each cut to make 10 staves …....


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## Jered (Sep 15, 2010)

Never made a bucket but you may want to keep a sharp ax and straw around for repairs.


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## shipwright (Sep 27, 2010)

Have you considered birdsmouth joints. They are simple to make, the angle is just sides/360 and taper doesn't change anything. All you need is a table saw.They are also self registering and deadly easy to glue. You can make a forty foot hollow mast tapered both ways.. foolproof. ... It's a great joint. Here's one link, I'm sure there re lots more. http://www.woodworkstuff.net/EDBirdM.html


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## Belg1960 (Jan 3, 2010)

I know this is an older post but wanted to add a calculator I found for the birdsmouth joint method.
http://www.clintchaseboatbuilder.com/resources/calculator-4.htm


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## Colonialhands (Feb 21, 2016)

Reply to an older post. I make colonial buckets as a hobby after attending a weekend coopering class 15 years ago in PA. Many good ideas on here for stave angles The angle is 360/no staves for the total angle. Divide that in half for each stave. That method only works if all staves are exactly the same width. In a barrel the staves are various sizes. An angle gauge can be made so that all stave miter angles are directed to the center of the bucket. Taper is about 1/4" to a ft. The bucket is tapered so the hoops or bands can be driven to seal the staves together. No glue. If you glue the staves they will eventually crack as they expand and contract around the fixed bottom.


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