Stretch Tethys.....

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Well-Known Member
Feb 20, 2009
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Finally got started on the mod to convert my Tethys to dual deployment. I've been kicking around ways to cut the QT bodytube and finally built three U-shaped brackets to hold the bodytube while cutting on my table saw. First I used some paste wax on the inside of the brackets to allow the tube to rotate easily. Then, I got it all squared up and clampled down, held the tube against the fence, raised the blade slowly and rotated the tube a complete turn before raising the blade more. Took about four passes so the cut would be clean. I made good use of the originally installed piston by positioning it where the cut was to be made to keep the tube from distorting while cutting.
This shows the QT after the cut was made. You can see the piston through the cut.

Well done, indeed. Power saws work great for cutting body tubes if you can jig up to properly hold the tube to maintain a good straight and solid hold as you have done with your set-up.

I use my Delta chop saw for cutting 4" and less tubes, including Quantum Tube, phenolic and cardboard/paper. I cut body tubes, motor liner tubes and casting tubes this way. Thankfully my saw goes a full 4" and not 'nominal' 4" (like 2x4 lumber). With your setup, you don't have the size limitation I do, just add a new set of jigs.

One additional useful tip: if you have access to a saw blade with a lot of teeth, like a trim blade rather than a rip blade, the power saw cuts the tube like butter and is extremely smooth.

Thanks for sharing, --Lance.
swimmer,the tethys looks like a sweet rocket!

same here Lance
I use my miter saw to cut all my tubing..even as small as bt-5 ..I installed a 72t carbide blade ,,it does very a nice job of slotting the larger tubes as well.! and will just clear a 4" dia tube.
The QT responded very well to even the rip blade (actually I forgot to put my trim blade on) and the cut is still very smooth. Thanks for the reminder Lance and stymye.

I have used my table saw several times to cut phenolic motor tubes and is the perfect tool for fin cutting.
oh no...that wasn't intended as a reminder Swimmer , I just enjoy sawing tubes on my miter saw mainly because, I don't own a table saw...

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