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My Home Made Bowl Turning Lathe
I have enjoyed wood working including wood turning for many years.When I turned my first bowl is the early 1980's using my old 9 inch South Bend metal turning lathe I was smitten. With limited funds to spend on a wood lathe I decided I would build a bowl turning lathe.
The following photos and text describes the process of building this lathe.
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This photo shows the finished lathe with the exception of adding the switch. It has a 1 horsepower motor with a speed range of approximately 575 - 2300 RPM.
As setup in the photo, an 18" diameter bowl can be turned, the bed can be lowered 5" increasing the turning diameter to 28". The bed can also be removed and an outboard turning stand be used to turn much larger diameters, limited by the motor location.
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Because of the limited funds I mention earlier I started scrounging for parts at scrap metal dealers. I found the pillar block shown in the photo and some bar stock to use for the spindle.
I turned the spindle on my Southbend metal lathe, the spindle is threaded 1 1/2" by 8 tpi, this is the same size as my metal lathe so my chucks and face plates will fit.
I built the spindle assemble in the early 1980's, it laid around the shop for years and followed me through several work related moves.
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The completed spindle assembly.
I did have to buy the four step pulley new. The appearance of the pulley is due to the many years of storing and moving.
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Jump forward to 2009. I was planing to retire at the end of 2009 so I decided to finish the bowl lathe that I started in the 1980's.
As you can see in the photo I now have a 12 inch Rockwell/Delta wood lathe.
The main post for the lathe was made of 4" "H" beam with approximately 5/16" thick sides and web. A 1/2" plate was welded to the top to mount the spindle assembly and feet were welded to the bottom.
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The lathe bed is made of 3" X 3" X 3/8" steel angle. The angle is welded to a 1/2" plate that will be bolted to the main post. Their are several sets of holes drilled in the post so the bed can be move up or down based on the diameter of the bowl to be turned.
The bed is 12" long. Generally this is OK, however, I did not realize that a bowl mounted in a chuck would extend so far beyond the post. The bed should be at least 18" long.
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The banjo is made of 2" X 2" X 3/8" steel angle and a piece of 3" bar stock with the upper portion turned down to 2" diameter with a 1" hole for the tool rests.
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The motor mount is made of 1/4" flat steel plate welded to 1/4" flat bar stock. The motor mount will be bolted to the main post.
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The semi completed bowl lathe out for a test drive.
Turning a 10" or 12" bowl from a reasonable well balanced bowl blank goes well, however, when turning a large out-of-balance bowl blank the lathe vibrates, actually, more of a twisting action of the main post.
To fix the vibration problem I welded a 4" X 1/4" flat steel plate to each side of the "H" beam, basicly creating a double box beam.
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Turning a 17" X 6" cherry bowl on the completed bowl lathe.
The lathe works even better that my expectations, it's bolted to the floor and is very solid.
The only two things I would do differently are:
1) Make the bed 18" long.
2) Build the main post out of 4" or maybe 6" square tube or box beam.
I have some improvements planned:
1) In the photo, I have to use a wrench to adjust the tool rest. I have already replaced this bolt with a new bolt with a handle in the bolt head, this makes it much faster to adjust the tool rest.
2) I plan to make a quick release for the banjo, this is currently in the planning stage.
3) I plan to move the switch to the back side of the spindle. Now it gets in the way when working close to the back side of the chuck.
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New and Improved Banjo (2011)
After several months using the lathe and always looking for the wrench when I need to adjust the banjo ("now where is that wrench, must be somewhere under this two or three inches of wood shavings") I decided to upgrade the banjo.
The new banjo is based on and uses the same cam action system that is used on my Delta/Rockwell Lathe.
It may look strange for the handle to be on the backside but it works well this way, I grasp the handle with my right hand and the tool rest post with my left hand and move the banjo where needed.
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New 18 inch Lathe Bed (2016)
When I originally built the lathe and lathe bed, I did not consider the distance the chuck extended beyond the spindle.
When I mount maybe a 6 inch bowl blank in the chuck it left very little distance to work with on a 12 inch bed.
The new bed is 18 inches long and is made with a 3 1/2 inch square steel tube with 1/4 inch wall. The steel tube has a 1/2 inch
slot cut down the center for the banjo to slide back and forth, it has two pieces of steel angle welded to the two top corners
to provide a solid surface for the banjo to slide on.
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New 18 inch Lathe Bed (2016)
After using the lathe with the new 18 inch bed for over 5 years, I can say that it's been a signifcant improvement, works great,
no need for additional changes.
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Upgrade to Variable Speed Capability (2016)
The one thing missing at this point was Variable Speed Capability.
I upgraded the motor to a three phase motor and added a VFD (Variable Frequency Drive)
to provide variable speed capability.
With a three step pulley system (2 to 6; 3 to 5 and 4 to 4) the lathe has a wide range of speed vs torque ratio up to 1725 RPM (the motor RPM).
The motor is a one HP motor, I should have upgraded to at least a two HP motor, however, at this point I'll stick with the one HP motor.
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Considering Building a Bowl Lathe?
If you may be considering building a bowl lathe similar to mine the following pointers and suggestions may help.
I helped a friend build a "Monster" bowl lathe, photo on the left, the lathe has a 13 HP motor and can hold 300 to 400 pounds of ballast in the box.
My friend has made many bowls with this lathe, the design is good, if we built another we would use the same design with no changes. The banjo for this lathe is a Oneway banjo purchased from Oneway.
My lathe is bolted to the concrete floor, my friend could not bolt the lathe to the floor so we built the lathe around a ballast box.
I found the pillar block for my lathe at a scrape metal yard and paid scrape metal price for it. Then I made the spindle to fit the pillar block.
If I were building another lathe today, without that pillar block, I would use a 6 inch square steel tube with 1/4" walls.
I would use two four hole pillow blocks, see the pillow blocks on the yellow lathe to the left, mounted on each side of the steel tube about 4” down from the top and drill a hole through the steel tube
for the spindle. Then build the spindle to fit. You could have the spindle made at most any local machine shop.
Make your spindle thread size the same as your other Lathe(s), or use a common lathe thread size, maybe 1 ¼” X 8tpi.
Leave a ½” collar behind the spindle threads, drill a 3/8” hole in the collar for a tommy bar to hole the spindle while removing the chucks.
The banjo is not an easy thing to build, consider buying one maybe from ebay or buying a new from one of the lathe manufacturer.
If you have any questions regarding either of the lathes on this page please contact me and good luck with your project.
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