Drilling distributor caps

[BigTallDad]

Although pre-wired distributors are available, some of us like to do it the old-fashioned way. The tutorial is separated into two sections: making the guide, and using the guide.

Making the guide. I used brass tubing, 1/32” and 1/64” inside diameter. With the help of a variable-speed drill and Dremel cut-off wheels, I cut a 1/2" length from each size. Make sure the lengths are equal! It is important to keep the length of the guide short; otherwise, a longer portion of the drill bit is exposed which increases the chances of breaking the bit.

I then inserted the 1/64” into the 1/32” tubing, with just a hint of the 1/64” protruding and soldered the two pieces together. The protruding 1/64” tubing will cause a small cup at the other end of the guide, thus the 1/32” tubing will be used to fit over the distributor nipple.

Next, I put a #78 (or so) bit in my pin vise and, using the guide for reference, set the depth of the hole.

Using the guide. I prefer medical tools (such as hemostats) to hold the guide, since they have the ability to lock. Make sure your holding device has “teeth” that grasp the guide, otherwise the dreaded “Ping, I wonder where it went” syndrome will rear its ugly head and you’ll need to make another guide. Needle nose pliers, with strong rubber bands around the handles, will also work.

I used double-sided masking tape (as used in putting new grips on golf clubs) A LOT! In this case, the tape is placed on a popsicle stick and the stick is locked in a small, vacuum-base vise. The distributor cap is then placed on the tape. Since one hand will be holding the hemostat and the other hand will be operating the drill, stability of the distributor cap is very important! Place the 1/32” end of the guide, insert the drill, and drill away. Remember, we’ve already set the depth of the hole in a previous step.

For photographic purposes, I darkened the hole with a lead pencil. As you can see, the hole is centered and is of the desired depth.

While this might not be everybody’s cup of tea, it certainly works well for me. If you find the #78 drill is too small, use it anyway, then graduate to a larger drill. The previously-drilled #78 hole will act as a guide for the larger bit and maintain centering.

[Ace-Garageguy]

Sheer genius !!

I WILL be using your tip every time in the future.

[Longbox55]

I'll be keeping this in mind as well.

[bobthehobbyguy]

Great idea. I always manage to mess up when I'm doing it free hand. Thanks for sharing.

[Harry P.]

Another great tutorial, Ray.

[chunkypeanutbutter]

Perfecto.

[Kit Basher]

Very cool! Where do you get 1/64" ID tubing? I have looked in several shops, and the K&S website, the smallest I have found is 1/16" OD. I guess the 1/16" OD is probably 1/32" ID, but I can't find anything smaller.

[Dragline]

This is handy. Thanks

Hows about you make a bunch and trade them off to those of us who want one?

Just a thought.

[Stray]

Another great tip!

I think the best idea here is just to move in next door to you and then get you to do all the fiddly bits. Yep.

[JohnU]

(Very cool! Where do you get 1/64" ID tubing? I have looked in several shops, and the K&S website, the smallest I have found is 1/16" OD. I guess the 1/16" OD is probably 1/32" ID, but I can't find anything smaller.)

Amazon has stainless tubing in small diameters for hypodermic needles. It's what I used for my drill jig. Many assorted sizes! Made drill jigs for exhaust pipes too.

Edited May 10, 2015 by JohnU

[BigTallDad]

(Very cool! Where do you get 1/64" ID tubing? I have looked in several shops, and the K&S website, the smallest I have found is 1/16" OD. I guess the 1/16" OD is probably 1/32" ID, but I can't find anything smaller.)

Amazon has stainless tubing in small diameters for hypodermic needles. It's what I used for my drill jig. Many assorted sizes! Made drill jigs for exhaust pipes too.

I found the brass tubing at my local hobby shop; if yours doesn't carry it, maybe they can special order it.

I've seen other tutorials where hypodermic needles were used, but thankfully not everybody has access to those.

What did you use to secure the two diameter stainless steel tubes? CA, resin, or what?

I went with the brass approach because the solder is (more or less) permanent.

Edited May 11, 2015 by BigTallDad

[vintagercr]

Ray, great tutorial.

[BigTallDad]

This is handy. Thanks

Hows about you make a bunch and trade them off to those of us who want one?

Just a thought.

That can be arranged, until I run out of raw material (contact me offline). I have but one rule...pay it forward.

[blunc]

that one's easy on this board, many here pay it forward all the time.

thank you for being one of them.