45 degree cut on a tube?

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RCMagic

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What is the best way to mark and cut a 45 angle on a tube?

Working on modifying a Super Neon XL


Thanks,
 
What is the best way to mark and cut a 45 angle on a tube?

Working on modifying a Super Neon XL


Thanks,

Best way is to generate a Tube Wrapping paper template using any one of several Mod-Roc programs. Roc-Sim, SpaceCad, VTC, Widgets, etc. Print it out, cut-it out, draw a center line on the tube, tape the pattern around the tube and tape in place. insert a backer mandrel that closely fits the ID of the tube. use a Sharp or stropped X-Acto or Razor blade to follow the out line around the tube. remove the excess tube and mandrel, sand lightly with 320 paper.

A bit more involved: mark two line along the length of the tube to be angles. one side will be the high side the other low. measure the lengths of the tube from your drawings high and low side. mark each on opposite sides of the tube measured from the same end. using masking tape carefully connect the two dots on each side of the lines (with two pieces of tape, one on left, one on right). Then cut with X-acto as explained above. This is how I cut the 7deg tapers on my competition cluster models. Couple pics below may help.

It is possible to just insert an expendable mandrel dowel or what-have-you and cut the angle of choice with an X-acto razor saw or on a band or jig saw. sand as needed to remove the burrs. I've Never liked this approach as it generally ends with not so good looking cuts and does waste some of the mandrel.

View attachment 7° Pod cutting Pics (1pg-12pic)_06-02-12.pdf

134-j4a-01_3x.5A Clu-Alt underside_04-07-12.JPG
 
Last edited:
Best way is to generate a Tube Wrapping paper template using any one of several Mod-Roc programs. Roc-Sim, SpaceCad, VTC, Widgets, etc. Print it out, cut-it out, draw a center line on the tube, tape the pattern around the tube and tape in place. insert a backer mandrel that closely fits the ID of the tube. use a Sharp or stropped X-Acto or Razor blade to follow the out line around the tube. remove the excess tube and mandrel, sand lightly with 320 paper.

I would second this, except I'd add that if you use a new (or otherwise very sharp) blade in your X-Acto knife you don't need a backer mandrel. Just go very slow and don't try and cut it in one pass. Use the tip of the blade and scratch the tube where you're cutting it, round and round. If you go slow enough you'll get all the way through the tube in about 3 or 4 passes and the cut will look good. Sand as needed when finished.

The key is to go slow, and not try to cut it in one pass!!
 
Or, using a little math, you could plot a sine wave and wrap the pattern around the BT.
To plot the sine wave correctly, plot the period of the complete sine cycle to match the circumference of your tube.
And plot the amplitude of the sine to match the diameter of your tube.
Simple.
 
Miter saw with a sharp blade. Provide internal backup for thin wall tube with wood dowel or spent motor casing.
 
Miter saw with a sharp blade. Provide internal backup for thin wall tube with wood dowel or spent motor casing.

+1 on the miter saw. Provided you have a miter saw.

If not, the whole paper template and sharp xacto works just fine. Just finished a FlisKits ACME Spitfire, which required making four angled cuts at progressively sharper angles, with provided paper templates.
 
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