Drilling tiny holes through thin metal pipe

[mad_dr]

Hi everyone. I'm looking for a couple of tips for drilling holes in metal pipework. If anyone has any experience or advice I would be very grateful.

I'm building an MFH 1:24 scale Ferrari 500 F2 and am trying to finish off the engine. It involves threading spark plug cables through a metal pipe between the distributors and the sparkplugs. The metal pipe that comes in the kit is actually a solid piece of metal with tiny notches that represent where the spark plug wires should go. I tried drilling the pipe to accept the wires but there's no way I could ever drill straight through the length of the pipe; it's far too small for that. Plus it's very soft metal so just bends and flexes.

The spark plug wires are so tiny they don't even like being glued to the pipe; there doesn't seem to be enough material to grab to the pipe.

The picture from my gallery below shows my first effort: I 'cheated' by cutting the wires and epoxying them to the metal pipe and tried to use heatshrink to hide the bad job. However I'm not happy with the finished result - there's far too much epoxy on show and it really doesn't look how I wanted it to.

So I've got more of the spark plug wire and I've managed to get hold of a thin brass tube to replace the bits of metal that came with the kit. This tube is hollow and is the right size. It has a 1.5mm outer diameter and 1.0mm inner diameter.

However, now I need to figure out how I go about drilling a line of three 0.5mm holes in the side of the pipe for the wires to thread through. I am confident that I can mark the places where the pipe needs to be drilled and I have a set of micro drillbits (including 0.5mm) and a pin-vice to hold them but my Dremel seems far too fast and difficult to control for a task like this; I think I'd end up struggling to get the drill to "bite" into the curved face of the pipe without it just slipping off

Additionally I'm sure that the pipe would be inclined to twist meaning that the holes would end up out of alignment with one another.

As I've got a 30cm length of the pipe and only need to end up with about 4cm of finished product, I'd thought of trying to make some kind of clamp that uses a V-shaped groove to let the pipe sit into and could epoxy the pipe to this trough to prevent it twisting/spinning. Once the holes were drilled I could cut out the sacrificial epoxied sections to be left with the bits I need.

I still need to figure out how to accurately target such a small point with a drill/demel though so any advice or thoughts about tools, jigs or techniques would be very useful.

Have I bitten off more than I can chew??

Thanks in advance for any assistance.

Andy

[Mike Kucaba]

You need to make a dedicated "miter box" or jig to guide the drill bit,and I'd suggest drilling by hand.

Use a block of hardwood,or aluminum and drill a hole in it to slide the tube into.Then drill a hole perpendicular to that.That hole will guide the very tiny drill into the tube where you want the wires to exit.

[Casey]

Are you using a hand-held pin vise to drill the holes, like this?:

[rel14]

Go to the book store and look at this months scale auto mag, April, pg 10 has the tip of the month and shows you how to make a jig and drill holes in round stock,,, hope this helps..

[mad_dr]

Hi All,

Thanks very much for your helpful suggestions above! I'll use them to plan my next steps and will let you know how I get on. My pin-vice is really just an adapter for my dremel/hand drill so perhaps I need to invest in a hand-held version.

I like the sound of using the block of wood or aluminium as a jig too.

Thanks again,

Andy

[crazyjim]

The SAE article says to clamp 2 pieces of flat stock together and drill through the center - like longways through the material. I'll tell you what - later on I'll go out to the shop, grab the article, scan it, and try to post it up here for you.

[crazyjim]

Here it is Andy.

[Pete J.]

I have a similar method for doing things as small as you are doing. The concept is the same as above but differant materials. I use a piece of 1/4" plexiglass and drill the 1.5 mm hole through the side. I then drill the .5mm hole through the top. Using plexiglass means that I can see my material to align the drilling spot. I have used this method to drill out the holes for hood pins in 1:24 scale cars.

[Mike Kucaba]

I have a similar method for doing things as small as you are doing. The concept is the same as above but differant materials. I use a piece of 1/4" plexiglass and drill the 1.5 mm hole through the side. I then drill the .5mm hole through the top. Using plexiglass means that I can see my material to align the drilling spot. I have used this method to drill out the holes for hood pins in 1:24 scale cars.

EXCELLENT CHOICE OF MATERIAL!!