sugestions on drillin holes in pipe

Clamp a spirit level to the pipe. Use a drill-press that's vertical, and have at it.

Snap a chalkline? Ken.

Attach (clamp or whatever is appropriate) a flat plate to one end of the pipe. Use a level on the plate.

Ken.

A common procedure in pipe fabrication is to use a centering head (curve o mark is the most common brand) with built in punch that allows you to set an adjustable level and center punch marks anywhere along a pipe, or other round material, at any ange you wish. Then just connect the punch marks with any method you choose.

JTMcC.

Clamp or otherwise fasten a long stiff rod or wire perpendicular to the pipe's axis/length. Attach a string with a nut or other weight tied onto the free end, near the same point as the rod. This will be used like a plumbob.. the longer the rod & string, the more accurate the indicator will be.

As you move the pipe, the string-to-rod angles will indicate the rotational position of the pipe. A disk or additional rods can be used as a degree positioner if the plumbob line is free to slip around the pipe.

WB ..........

use a level on this rod to make it vertical (level), drill next

Plumb Maybe. :-) ...lew...

A piece of angle iron can usually make a decent straight line on a round peice of work. But, if the holes need to be absolutely 90 deg to the top of the pipe, you might need to search elsewhere. Drill one hole in the center of the pipe, find a rod that fits snuggly in the hole, use a level on this rod to make it vertical (level), drill next hole, and so on. Drill holes with a hand drill at what looks to be the right angle, use torch and pipe wrenches to align holes so they are in the desired place.

Lynn

Assuming you are drilling with a drill press, clamp the pipe inside a length of angle iron, slide the angle iron along a fence clamped to the table as you drill.

1. If using a drill press, clamp pipe to a angle iron or straight 2x4 and slide along a fence mounted to table.

or,

1. Make a jig to hold your marker. Take a block of wood, drill a hole through the center of one face to hold your marker (pencil, scribe, etc.). Cut a notch in the other face the same width as the pipe OD, like so:

__ | | |__| | | |P | |e | |n | |c | |i | |l | | | ___________________________________ | : : | | : : | | : : | | ___________ | | / \ | | | | | | | | | | | | | |__________| |__________|

Paint jig to resemble Arc de Triomphe.

Secure pipe to a flat surface and slide jig and scribe along length of pipe.

Drill on the scribed line.

R, Tom Q.

Set up V-block(s) on drill press table so drill will be centered on pipe. Drill one hole. Hang plumb bob on string were yo can sight along pipe at it. (Alignment need only be rough.) Clamp a piece of rod or a drill in that first hole. Position pipe and rotate so rod and string line up.

You can use a level as pointed out elsewhere if you have one sensitive enough.

Ted