Twisted Square Ambrosia Maple Bowl

[Thomas Canfield]

Here are 2 twisted square ambrosia maple 6x6x4 pieces with base square 45 degree offset. I had tried turning a smaller square base before and then decided to twist the base. I used a base pattern screwed to bottom and then a router with pattern bit to cut down the bottom outside the base about 3/4". I initially turned the large upper section outside and the area above the base, then turned the inside of the base with tenon to be used to turn inside. Reversing and using live center in tailstock due to small tenon and height, started turning inside working down in segments maintaining pressure with live center. Nearing bottom of inside, removed live center and finished turning. Piece was then held with vacuum chuck (or jam chuck) to turn off tenon. Makes a different look. Plan to try similar procedure with a large circular bowl or tray to make a square base as something different. Fun.
Twisted Sq Ambrosia Maple 1.jpgTwisted Sq Ambrosia Maple 2.jpg

Photo shows both on base and other show top of one and bottom of other.

[Dave Mount]

Very clever. I had to read the process twice to get my head around it. Folks are so inventive, it makes me feel like such a dullard making all round stuff...

Great work -- thanks for posting it!

Best,

Dave

[Lawrence Duckworth]

Two very nice piecesThomas.What wipes me out is you guys do this from a square.... images of a buzz saw come to mind

[Gary Pennington]

They are super cool. I'd love to see a pic taken from the side?

Thanks, g

[John K Jordan]

They are super cool. I'd love to see a pic taken from the side?
Thanks, g

I suspect Tom will post a photo from the side. He's an incredible turner.

In the mean time, his creation reminded me of this one I made years ago, I hope he doesn't mind if I post it here. It's not the same technique but it IS a picture from the side! These joined bowls are not square but 3-corner bowls made with perhaps a similar but somewhat different technique.



If anyone hasn't turned a 3-corner bowl it's typically made by starting with a cube and supporting it between centers by two opposing corners. Turn the outside and a tenon on one end, then reverse and hold by the tenon to shape the inside. Jam chuck to finish the bottoms but the vacuum chuck would work as well. For this I made a second one from east indian rosewood and the top is very punky spalted yellow poplar stabilized with CA. A kind and thoughtful gentleman, Steve Criscenzo, brought me the fishing net float from one of his trips the Marshal Islands. I thought the blue glass looked nice with this piece

JKJ

[Thomas Canfield]

Tom here. Here is the side view photo of the ambrosia maple pieces requested. The other photo shows some of the progression in figuring out the proportions and techniques. The early work was done on glue up 2x6 and 2x8 pine to get the thickness. The 2x6 piece was done as demo piece for Hill Country Turners, Kerrville, TX a couple of weeks back and I told club they were not worth a $30 blank for demo - it really worked out well to get the process across and not be concerned with finish product. The blue painter tape on corners does help watch for the flying edges. The 8x8x4 Khaya piece on Nova 50 mm jaw chuck is in progress needing finish sanding exterior and then remounting with vacuum chuck to finish base inside. I found that it worked easiest by working the upper exterior first and then working the transition between the upper and base. It gets a little tricky working to the intersection of upper and base and that is why I have found leaving the sharp ring can be done with a spindle gouge fairly easy and still produce a clean cut. One has to work out the proportions to meet his own eye as to curves, but the wings on the upper and feet on base seem to be key features.Twisted Sq Ambrosia Maple side view.jpgTwisted Sq Bowl Progression.jpg All the pieces were turned on a Rikon 70-220 midi lathe except the demo was done on a Powermatic 3520A at club meeting. The 8" Khaya is almost 11.5" across corners on the 12" midi lathe but no problem for all out there with only midi lathes. I used the 50mm jaws on the base being careful to use live center as much as possible. To start, I mounted the piece on a worm screw in 100mm jaw Nova chuck to get more face contact. Try it, have fun, but be safe.

[Gary Pennington]

I suspect Dave will post a photo from the side. He's an incredible guy and turner.

In the mean time, his creation reminded me of this one I made years ago, I hope he doesn't mind if I post it here. It's not the same technique but it IS a picture from the side! These joined bowls are not square but 3-corner bowls made with perhaps a similar but somewhat different technique.



If anyone hasn't turned a 3-corner bowl it's typically made by starting with a cube and supporting it between centers by two opposing corners. Turn the outside and a tenon on one end, then reverse and hold by the tenon to shape the inside. Jam chuck to finish the bottoms but the vacuum chuck would work as well. For this I made a second one from east indian rosewood and the top is very punky spalted yellow poplar stabilized with CA. A kind and thoughtful gentleman, Steve Criscenzo, brought me the fishing net float from one of his trips the Marshal Islands. I thought the blue glass looked nice with this piece

JKJ

Thanks John,

That's a wonderful piece. Also thanks for the 101 on turning a 3 cornered bowl, that's a long way above my skill level. Hopefully my turning will continue to improve so pieces like this are doable.

Thanks again, g

[Gary Pennington]

Tom here. Here is the side view photo of the ambrosia maple pieces requested. The other photo shows some of the progression in figuring out the proportions and techniques. The early work was done on glue up 2x6 and 2x8 pine to get the thickness. The 2x6 piece was done as demo piece for Hill Country Turners, Kerrville, TX a couple of weeks back and I told club they were not worth a $30 blank for demo - it really worked out well to get the process across and not be concerned with finish product. The blue painter tape on corners does help watch for the flying edges. The 8x8x4 Khaya piece on Nova 50 mm jaw chuck is in progress needing finish sanding exterior and then remounting with vacuum chuck to finish base inside. I found that it worked easiest by working the upper exterior first and then working the transition between the upper and base. It gets a little tricky working to the intersection of upper and base and that is why I have found leaving the sharp ring can be done with a spindle gouge fairly easy and still produce a clean cut. One has to work out the proportions to meet his own eye as to curves, but the wings on the upper and feet on base seem to be key features.Twisted Sq Ambrosia Maple side view.jpgTwisted Sq Bowl Progression.jpg All the pieces were turned on a Rikon 70-220 midi lathe except the demo was done on a Powermatic 3520A at club meeting. The 8" Khaya is almost 11.5" across corners on the 12" midi lathe but no problem for all out there with only midi lathes. I used the 50mm jaws on the base being careful to use live center as much as possible. To start, I mounted the piece on a worm screw in 100mm jaw Nova chuck to get more face contact. Try it, have fun, but be safe.

Thank you for the excellent description. I was wondering how you handled the transition between the top and the base--the look you gave them is very elegant--in fact the pieces are wonderful overall. Your explanation is clear and I appreciate the caution re: the rotating corners with blue tape. I've turned a couple square bowls and have managed to keep my remaining fingers/hands out of the rotating mass but will certainly apply blue tape going forward.

Hopefully your club enjoyed not being worth $30 for a chunk of demo wood--I think I'll employ your construction lumber glue up for an unprofessional attempt to emulate your design. Thank you for posting,

g

[John K Jordan]

...Your explanation is clear and I appreciate the caution re: the rotating corners with blue tape. I've turned a couple square bowls and have managed to keep my remaining fingers/hands out of the rotating mass but will certainly apply blue tape going forward.

I was glad to read the excellent posts by Thomas as well.

I haven't done it (yet) but can imagine running a finger into a whirling fan blade would be painful!

Something I found helpful to let me see corners is a very bright task light. I use a supernova from Woodturners Wonders directly on the corners and make sure I have a contrasting background. For a very dark wood I might put something lighter behind but the bright light is enough for most things. This is a 4-corner platter. The light helps maintain tool presentation and control when starting a cut directly into the corner from the air when alignment with the existing surface is important.

The bright light is so important for me I take one with me when I do club demos where I'll be "turning air."

In this picture, I'm using a negative rake scraper to smooth the corners. The flat on the end works well with a delicate touch, taking off just "whispers" of shavings. I've been told you can't use a scraper on corners but this works for me.
NRS_IMG_7515.jpg penta_platter_variationIMG_7451.jpg

I do use tape at times, but not on the piece. I mark the tool rest, showing just how far hard-to-see corners extend


JKJ

[Lawrence Duckworth]

I really thought this process was done round and then squared up on a saw. The tape on the corners sounds smart

A2C6BFD0-B315-43B3-A503-22E880784822_1_201_a.jpg

[Thomas Canfield]

I really thought this process was done round and then squared up on a saw. The tape on the corners sounds smart

A2C6BFD0-B315-43B3-A503-22E880784822_1_201_a.jpg

I can't see the base on that piece but the wings are clearly airborne and delicate. Someone did an excellent job on turning and the inlay. Shows what you can do to optimize a square block of high priced wood (or is this some cheap wood that was ebonized?). Got to have some fun doing this.

[John K Jordan]

I really thought this process was done round and then squared up on a saw. …

Some people have done non-round shapes that way. I can think of several disadvantages to that method. One, you have to start with a significantly wider plank and more is wasted (unless you glue waste edges on the blank to be cut or split away after turning).
Worse, it is more difficult to get the edge thickness even (or to the shape you want).

With some wood and shapes it might also be hard after finish turning and smoothing to cut the non-round shape cleanly or even safely on the bandsaw without special prep and a lot of hand work to cleanup chipping, splintering, and such.

I think cutting the blank to shape before turning is easier overall. For my “squarish” shapes I make templates from clear plastic I can slide around and position on the board to make the best of grain, figure, color, and avoid unwanted defects. I trace the outline, cut the blank out on the bandsaw, then smooth the profile with a 10” disk sander before mounting for turning.

[Lawrence Duckworth]

Thomas, I can't remember for sure but I think this was cherry and the epoxy dye bled into the ends of the inlay channel and looked bad so indian ink was used to cover the mistake. This piece is mediocre at best. I was just trying to point out my ignorance to the process and that I turned this round like a bowl and squared it up on a dewalt radial chop saw. I might try doing it the way it's supposed to be done later on but probably best to see someone demo it first.

I really like the style and form of your pieces...and the special twist!