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Alternative Pie Segment cutting method

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The June 2022 issue of American Woodturner article titled "A Table Saw Sled For Precision-Cut Staves" and I am in the process of developing what I view as a better way. The 2 photos show the first trial using basswood planed to 1 1/8" (28.575 MM) thick and cut to 3 7/8" (98.425 MM) wide.
PieSegTest2.JPG
This photo shows the angle cutting jig just imagine a long board clamped in place the with the right hand on the clamp pushing forward and against the fence and the left hand supporting the end of the board the cut is made. The next step is to set the cut off piece and the board next to each other on a flat machine surface and mark the second piece for cut off on a miter saw. The final step is to repeat until enough segments have been cut. The point in the center of the wide end is nothing more then a 90 degree cut with the sloped side against the miter saw fence. The only waste will be the saw cuts and the little triangles from the end.
The jig was made using a digital protractor to lay out the position for the fence, then screw the fence down with the clamp attached. The length of the segment can be adjusted simply by moving the stop block however the clamp may need to be repositioned. The angle to set is 2 times the Miter angle listed on the chart in the magazine (the jig shown was made to 21.8 degrees).
Pie segtest1.JPG
The angles are made on the jointer using the blade angle from the chart. The white pine plank on the outboard table was used to verify the angle by checking with the digital protractor and the depth was set to assure that the entire edge is angled. The segment is placed as shown with the grain parallel to the edge up so the angled grain is cut on the shear then the piece is flipped end for end for the second edge angle. The tapped up assemblies on the inboard table indicate that no adjustment to the angle is necessary ince they both sit flush on the machine table.
8Seg10.5Inch.JPG
This is one of several pie segment experiments that did in September 2021 to see if I could make the point come together accurately and the segments were cut using a similar jig, but they are flat so 360 / 8 = 45 degree or twice the miter angle as listed for zero slope. The glue up was simpler in that I glued up 4 pairs using clamp blocks that allowed clamping pressure to be perpendicular the the joint so I could more easily align the points then make an accurate 90 degree cut to spread the correction error over at least half of the pieces. The trimmed 1/4 sections were then glued into halves and trimmed as necessary and lastly the corrected halves were glued together.
 
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Some thing I have been pondering.... I remember seeing 'the ultimate table saw fence' thing on You Tube, and it had about a 12 inch tall fence. All sorts of 'adjustments' could be made.

Also, I was wondering what the brown side things were on your glue ups, then I remembered the masking tape trick. Excellent job of fitting that together...

robo hippy
 
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Also, I was wondering what the brown side things were on your glue ups, then I remembered the masking tape trick. Excellent job of fitting that together...
The masking tape is for dry fitting as they have not been glued up yet. The article in AWT shows the 2 dry fit tape ups being held up to each other to check the fit but those 10" segments got a little awkward so setting them on a machine table seamed like a better option.
The next step/challenge is to figure out how to clamp them for the glue up.
 
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The next step/challenge is to figure out how to clamp them for the glue up.
A band clamp? I have not done any segmenting, but looking at that, I am thinking a band clamp around the perimeter of the whole thing would work. You might have to check frequently as you tighten it to make sure everything is in proper alignment. For small pieces that the band clamp is too large for, perhaps a hose clamp. This is, of course, assuming you just need it to hold until the glue dries
 
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A band clamp? I have not done any segmenting, but looking at that, I am thinking a band clamp around the perimeter of the whole thing would work. You might have to check frequently as you tighten it to make sure everything is in proper alignment. For small pieces that the band clamp is too large for, perhaps a hose clamp. This is, of course, assuming you just need it to hold until the glue dries
Thanks for replying! The band clamp might work if the slop was zero or the edges were all 90 degrees to the face but this trial is using a 15 degree slope that results in a edge angle 2.9 degrees less then 90 or 87.1 degrees. Refer back to the dry fit tape up and you will see why the band clamp will not work. The other problem is that I am trying to accomplish a glue up without a hole in the center so in order to maintain the precise alignment necessary at the sharp ends I am clamping one joint at a time. The 8 - 2 segment pairs have have been done with fairly simple clamp blocks, but the 4 - 4 segment pairs require a much more complex clamp block. The 2 clamp blocks each consists of the contour cut into a 1-1/2" red pine and that is glued to 3/4" board. The inside of each half has first a 2.9 degree pie shaped sliver then a 5.8 degree sliver which will match the exterior contour of the 2 segment pairs. The long edge of the pair has 11.6 degree wedges to match the angle of the segment pair. The glue block to the right is glued to a plywood backer and during clamping the left one is lightly clamped to the plywood backer. The final step is to apply glue to the joint, bring the 2 - 2 seg. pairs together, verify alignment then gently clamp with 3 bar clamps as shown in the second picture. Note the clamp under the blocks will prevent the whole assembly from bowing.

PieSeg15DS.25SectionClampBlock.jpgPieSeg15DS.25SectionGlueUp.jpg
 
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Ah, I missed the compound bevels. I was thinking just a flat ring. With the added angles, the band idea would very likely not work - unless you define working as folding all of the segments up into a messy pile :)

I think what you have in your second picture with the bar clamps is probably best for what you describe. If you have adhesion issues with the piece you glues up sticking to the clamp fixture, pieces of wax paper should work. I have used that in the past where I was gluing up something that I knew would be messy - an d there was not really a reasonable alternative. Sure, the waxed paper may stick a bit, but it comes off a lot easier than finding you have not only glued your segments together, but glued them to the clamping fixture as well. That would be cause for the use of colorful alternate language to let the piece know exactly how displeased you are :D
 
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sticking to the clamp fixture, pieces of wax paper should work.
The actual glue joint does not come in contact with the clamp fixture in this application, however I have made clamp fixtures for other applications where it is necessary to isolate the work piece from the fixture. The use of wax paper to prevent the work piece and fixture becoming one does not always work since the wax paper can rip or get saturated with glue so I have gone to using about 2 mil poly sheeting and that can even be reused.
 
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