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menhir 01-24-2020 10:59 AM

Tool suggestion for cutting soundport
A little background first.

Since I removed a malfunctioning Micro EQ from my Seagull M6 about a year or so ago, I already have a soundport, albeit an ugly, oddly shaped one. It's not very large at all.
I'm leaning towards keeping itt and if I do, I'd like to make it a bit prettier.

What hand tool would be right for the job? I have a lot of tools but nothing that I'd trust to the fine cutting needed. I considered using a fine blade removed from one of my coping saws, but I'd prefer something with a handle that I could grip for better control.

I have a Dremel but I'm not sure which bit would be recommended. If that's the best way to go, fine, but I have a concern that the tool may get away from me...I always prefer hand tools.

For the record, I don't expect to sell the guitar, ever, so that doesn't enter into the equation.

Big Band Guitar 01-24-2020 11:19 AM

A good sharp X-acto knife carve out a little at a time.

Cover the area with masking tape. Draw the new hole shape on the tape. carve only the smallest of slivers.

printer2 01-24-2020 11:20 AM

Then take a cylindrical object wrapped with sandpaper and refine the hole.

hermithollow 01-24-2020 12:45 PM

My suggestion would be that rather than recutting the hole and making it larger, that you make a "purfling ring" to bind it and make it smaller. Some purfling rings sit a little proud of the surface and not all of them are round. It can give a finished appearance to the "sound port" left by removing the electronics without risking making a new one. You could apply it with double stick tape (as they do some pickguards) and replace it with something else if you want to at a later date.

stormin1155 01-24-2020 01:00 PM

I'd use the Dremel with one of the little sanding drums to shape the existing hole into what you want. (Obviously the picture is larger than actual size....)

JMFingerstyle 01-24-2020 01:15 PM

I agree with the idea of using the Dremel sander (or, even better, the purfling ring). The M6, if I'm not mistaken, has laminated mahogany sides. From my own experience cutting a hole for a Fishman "barn door" on my laminated Seagull, it's very hard to prevent the inner laminate layers from splintering to some extent when cutting, whether using an X-Acto knife or other cutting tool or file.

While that may be fine when installing a barn door, it's not so nice when doing the opposite. Because you don't have solid wood, the port is always going to look (and feel) somewhat unfinished.

Can you perhaps cut the center electronics out of the Micro EQ you removed, and reinstall the brass outer ring?

redir 01-24-2020 02:16 PM

If you want a round hole then believe it or not hole saws work well. Just make sure it's brand new and sharp and don't force it. I always reinforce the inside with a veneer first. I drill a hole (use the same size bit if using a hole saw) and then use that LMI Friendly Plastic to make a caul the exact shape of the side. Drill through that then clamp up the veneer with a bolt or some such method.

TEK 01-24-2020 05:00 PM

Use a wood dowel with sandpaper wrapped around it. Start with pretty coarse paper and as you get close to the size and shape start using finer paper. It will be slower going but safer than power tools which can grab and crack sides. The bigger the dowel the easier it is to shape the hole nice and round.
Or you can make a cover like I did for a friend who had a cheap guitar that the electronic no longer worked on. He wanted to take out the electronics but also didn't like the square hole. I made this out of mahogany and drilled the mount holes in the same location as the electronics so he could always go back if he wanted.
Good luck

menhir 01-24-2020 05:21 PM

Thanks for all the help. :up:

The good news: I have X-acto knives, drills, masking tape, and the sandpaper dremel bit already on hand. I may even have a hole saw, too. I'll have to go down and look through my stuff. That means I won't have to buy a specialized tool for a one-off job.


The M6, if I'm not mistaken, has laminated mahogany sides
Close enough. it's a wild cherry/mahogany laminate. Your point is taken, though. I want to try to minimize any scarring inside or outside. I have some veneer lying around I could use as a backing.

As far as just re-mounting the Micro-EQ plate back on the guitar, I considered that, but it's any ugly little spud. The soundport would look better.

Here's what it looks like with the EQ removed...
The hole is not much larger than a guitar pick. I'd have to cut away enough to get past those screw holes anyway.

I'm considering cutting out the indentation marked left by the mounting plate. You can see it on the pic.

I never thought of a purfling ring before now. I'll look into that.

Brucebubs 01-24-2020 06:23 PM

.. only kidding.

mirwa 01-24-2020 06:51 PM

I just use routers with templates, gives a perfect cut


Bruce Sexauer 01-24-2020 07:32 PM

I cut my last one (last week) by drilling a hole in the side inside the drawing I had made on the side, then roughing it out with the saw StewMac sells for creating bridge pin slots in the bridge. Then I carved it to the lines with a sharp knife, and finally finessed it with files. After that I created a reinforcement (piece of extra side with the grain 15 degrees out of line to prevent cracks) and HHglued it inside the guitar and repeated the process above till it fit the port.

Looks like this:

Frank Ford 01-25-2020 12:43 PM

Router, Dremel, tiny hand saw, "chain drilling" with appropriate cleanup afterwards - these are just a few of the logical options.

I wouldn't rule out the hole saw pictured above, but I'd use it with drill press.

Last week I did a very neat job in a tenor ukulele. I used a sharp 1-3/4" Forstner bit in the drill press. Had some help - had the instrument clamped immobile against a vertical fence, and one of our guys holding the neck to eliminate any vibration.

Job went super smoothly, with only a quick swipe of 220 grit sandpaper to clean it up before a light coating of shellac on the cut edge.

surveyor 01-25-2020 06:11 PM

Thought I would get creative when I built these and build in sound ports for my area, even though I live in Texas, Louisiana is a stones throw away. I used a dremel, small files and sticks with sandpaper glued to them.

Carey 01-25-2020 08:28 PM

I've used a sharp Forstner bit in a cordless hand drill to cut a soundport, and it
went really well.

menhir 01-28-2020 04:11 PM

Thanks for all the help and advice.

I have the tools set aside and I'm just waiting for a nice open day to get the job done (among all the other to-do's that were waiting until I retired to get done. ;) )

I'll post a pic of the finished result.

menhir 02-07-2020 04:29 PM

Well, it's done. :)

I cut the shape around the mark left by the old pre-amp. I sorta liked the look.

It was done with a sharp blade, patiently scoring the shape over and over again until it cut through. Then some shaping with flat and curved files, a fine round file for the tight corners and some sanding. I followed up with a bit of Minwax Sedona stain on the inside edges.

The edges blend in perfectly, but for some reason, they look much lighter in the image...It must be the lighting. I may apply a bit of satin varnish on the edges after the stain dries. Maybe not...the guitar is a satin finish anyway.


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