simple tube layout?

Clamp tube to bench. Set height gage for 1/2 tube dia. Scribe both sides of tube.

"Don Foreman" wrote: Clamp tube to bench. Set height gage for 1/2 tube dia. Scribe both

^^^^^^^^^^^^^^^^^^^^^^ Or: Measure tube circumference accurately. Set mark half-way around. To check accuracy, do it again the other way 'round. If the two marks do not agree, go half way between them.

You could check accuracy on Don's method by turning the tube over, just in case your height gauge setting isn't spot on.

1. Wrap a sheet of paper around the tube, aligning the edges where they overlap to square it. Mark the corners of the inner layer on the outer layer. Remove the paper, connect the marks and cut the line. Fold the paper in half and crease it. Put it back on the tube. The crease is one line, the abutting edges are the other. You'll need to use a Legal or B size sheet.
2. Stand the tube upright on paper and trace the circumference. Lay the corner of another sheet over the drawn circle and align the corner with the line. Mark the circle where the two edges of the top sheet cross it. If you were careful a line between the two marks is a diameter. Cut out the circle and slide the paper over the tube.
3. If your first line on the tube is near the end, you can use the center finder head on a combination square to locate the second one.

Jim Wilkins

Place two tubes side by side and secure together - duct tape works ok.

Use a big magic marker to color in a fat line down the length of the tube.

Slide a hard straight edge down the length to scrape off a narrow straight line.

Rool 'em over.

Do it again.

Got it, thanks. I was mitering a 45 degree cut, then rotating one piece to make a 90 degree bend. All done, looks OK too (it's just for a barbecue).

Grant

I clamp angle iron to pipe with U bolts before making miter cuts. There's no layout except marking the length because the angle squares it in the saw vise, and I have flat clamping surfaces to align the pieces for welding.

To attach a piece of angle at the other end parallel with the first one I clamp a piece of bar stock on crosswise and level them both or align them by eye.

Jim Wilkins

OK, here's an odd idea: Take two files, and clamp them both to a bar, maybe 6" apart, so they are both perpendicular to the bar. Rest the bar on the tube, and turn it at an angle from perpendicular until both files contact the tube, then drag along.

I have no idea how well it would actually work, though. :/

--Glenn Lyford

THAT'S the kind of ingenuity I like to see. :-) ...lew...

This depends on the edges of the files being exactly 90 degrees to the bar; especially tricky with files that have a curve to their edges.