Pipe drilling jig

[Bill Stock]

I need to drill many 3/32 holes in a 1/2" CPVC pipe about a 1/2" apart. Best idea I have is to use a shelf hanging bracket to cradle the pipe and use the holes in the bracket to estimate my 1/2" movements. I would draw a line along the edge of the bracket when I start to make sure I don't roll the pipe as I move it.

Any better ideas?

[LCHIEN]

you don't say how long the pipe is.
You also don;t say what the requirement for co-linearity and hole spacing accuracy is and whether its cumulative or absolute.

There's two techniques i'd consider depending upon the above.
One is to fasten the pipe into square blocks so that the pipe is prevented from rotating and the same angle for each drill. Just drill a hole in the blocks and put a set screw into it to hold the pipe and keep it from rolling.

Another way is to have a flip up bar attached to the DP fence The bar has a pin. Locate the pin exactly 1/2 inch left from the drill bit center and when it flips down will hit the pipe directly top dead center. When you drill the first hole (pipe against the fence), then you shift the pipe left, flip the bar so the pin hits the hole, drill the next hole, lift the bar, slide the pipe and put the pinin the last hole. This indexing system will work well BUT errors will accumulate, if the pin is not dead center then the line of holes will spiral a bit around the pipe, if the pin is not set exactly 1/2" from the bit then the holes will be equispaced but not you may end up with 50 holes over 24 inches when you expect 49.

[Bill Stock]

you don't say how long the pipe is.
You also don;t say what the requirement for co-linearity and hole spacing accuracy is and whether its cumulative or absolute.

Spacing is not critical as long as it's fairly consistent, roll is more important for aesthetic reasons.

[conwaygolfer]

Why not

clamp the pipe into a piece of angle iron (bed frame steel, etc.). This will keep it from rolling. Chalk or pencil a line from one end to the other. Drill holes along this line. You will just have to prop up the angle iron to get the correct angle for drilling. This could be drilled easily with a portable hand drill since it is only 3/32 in.

Thanks,
Glenn

[cabinetman]

Make some "V" blocks to hold and keep the pipe from turning. You can use dabs of hot glue. Draw a line on the pipe and mark off the holes.

.

[Salty]

This may also be of use. It only goes down to 3/16" on the guides so you would have to use an additional bushing.
Rockler sells them for about $16