Need to enlarge 1/2" output jack hole to 7/8"

I suggest you use a coarse round file.

 

You want to use a Unibit. They are available individually and in different sizes.

 

I have at least four different step drills, and they are very handy for drilling thin materials, but I think the OP wants to enlarge a side hole in a wood body, not in thin stock like a pick guard or jack plate where a step drill would be a good choice.

(sissy kathy, notice the mention of plugging the hole with a wood dowel to make it possible to use a forstner bit).

Since asking the question tells me that the OP is not very experienced with this type of work, I thought that a low cost basic tool like a round rasp would make it easy to sneak up on the desired larger hole size with low risk of tear-out, or personal injury.

OP. Are you enlarging the hole in a pick guard, or jack plate? Or, is it a side jack in a wood body? If it is thin stock like a pick guard, or jack plate, a step drill would be a perfect tool for the job, but I paid about 60$ for the last Greenlee step drill bit I bought. If it is thin stock, a fine round file would work, and if wood, a round rasp, or more coarse file would work at a cost of about five bucks.

Enlarging an existing hole in thin stock, or a wood body with a 7/8 inch twist drill bit in a hand held drill motor is asking for trouble, but if it is a side hole in a wood body, you probably could do it if you are careful.

 

Very worthwhile modification ‘cause barrels stink. Electrosockets are great.

I’d do this. Easy and safe. 2pcs 1/8-1/2 Inch And 5/32-7/8 Inch Bridge Hole Tapered Hand Held Reamer Set | eBay

You don’t have to eBay but good ones can be expensive. Check around.

 

The problem with a tapered reamer is that it makes a tapered hole. A straight hole is required. If a tapered reamer was used it would be best to get close to the desired size, and finish with a tool, (file) that would result in a hole with parallel side walls.

A set of two reamers shipped from Hong Kong for ten bucks makes me think that the quality of the tools will not be very good. I admit that I am a tool snob. Sorry.

A five buck, (or less) coarse round file would do the job cheaper and as good as a tapered reamer and a file.

A step drill will not drill a deep enough 7/8 inch hole in the side of the body of a wooden instrument because the required depth of the hole is greater than the step of the bit.

 

I'd use a step bit to get the outside of the hole cut to size and centered properly, then a regular 7/8" to make it cylindrical. You should get enough cut with the step bit so that the full-size bit doesn't wander.

 

Neutrik makes a 2 conductor (mono) and a 3 conductor (stereo or for on/off switching of built in electronics) for less than $2.00. Much better quality than factory installed barrels.
Neutrik NYS221 3 conductor 1 4 Female Phone Jack Thick Panel | Full Compass

 

You might find a luthier who would increase the size of the hole for you for less than the cost of a step drill, and 7/8 inch reduced shank twist drill (commonly referred to as a "Silver and Deming" drill bit).

If you were local to me, (on the sceniec north shore of Pewaukee lake), I would do it for you for free.

 

I have two basses with the Neutrik stereo barrels in them going on five years (I had replaced the originals at the same time and I use Aguilar pres)

Going from a 1/2" hole to a 7/8" hole is rather severe and I would personally look for a luthier who would have the correct tooling to do a great job if you're determined to go that route

 

I would never buy any tools from Harbor Frieght myself, but for the one time use of your purpose, this set: Rasp Set 3 Pc includes a round rasp that you could use to increase the size of the hole at a cost of four bucks. (Please don't ever tell anyone that I recommended a Harbor Frieght tool).

You might find a better tool at your local Ace Hardware store.

Nicholson makes excellent files and rasps, (like the 1/2 inch diameter round ones here: http://www.nicholsontool.com/files/diameter/1/2-in).

 

For a bass that inexpensive, I'd be tempted to just drill it out a step or three at a time; as in 5/8" to 3/4" to 7/8". Just clamp it down on your bench/table, and have at it...

 

Electrosockets are only about 3/8” deep so you simply continue through to that depth in the hole. Plus If need be, once the hole is sized to 7/8 by the reamer, you can open it further with a conventional twist drill

 

This works. Another good reason to keep an old fashioned hand drill (egg beater) in the shop. Turning the dial slowly allows the drill bit to seat within the taper. Smooth sailing after that.

Of course, a drill press and vise work like a charm, too.

 

I've got a variety of instruments dating back to 1978 and haven't ever had to replace the jacks on any of them. I am kinda finicky about tightening them back down when they need it, though.

 

I agree, some paint chipping isn't a big thing. I am saying that depending on the wood itself that you'll be drilling, would it splinter or crack leaving you with a situation worse than you envisioned. I'm not familiar with the model bass you want to mod but I once tried to drill a headstock for larger diameter tuners and even though I was going from 12mm to 9/16" that damn head split and I had to purchase a new neck. Good luck

 

I like unibits. All good advice here. DO NOT try to use a twist drill, thinking you can hold it steady- You will make an ungodly mess.