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I've spent the whole morning heating, wetting, bending cutting different materials to try and get a sound port bound (inside). Its simply a round port, nothing fancy, but I'd like to give it some depth looking down into the port.

I'm just trying to make the port look more "intentional" I suppose. I feel like anything out of the ordinary like that automatically draws the eye so it should be well done.

So when you do a sound port how do you bind it?
Thanks so much.
b

The ones I made I didn't really add binding
I used different colored woods/veneers laid up for the reinforcement on the inside. I cut the sound port with a bevel to reveal the different colors.
Works for pegheads too. For me it just seemed easier and with fewer steps.

I also found the reinforcement on the inside provided the depth I wanted so I don't bind them either. I make the reinforcement from a dark wood and use maple veneer in the middle.

I have seen where others made what is essentially a tube out of solid wood then glued it in to trim the hole.

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Steve Smith
"Music is what feelings sound like"

On the last three that I did, I cut the port with a sharp hole saw. I cut the same hole in a price of plywood (lined it with packing tape) and built my blind ring inside of that. This allowed me to force my binding and purfling veneers into the circle for glue-up and have the OF perfectly match the ID of the port. The resulting cylinder slides I. The port and I can mark the curvature of the inside and cut it to match. Then once it is glued in, I can flush it up to match the curvature of the outside. You pretty much have to do it before the plates are on, or at least it is much easier then. I have even laminated some veneers that match the purfling lines inside (covering up the hole). Then cut the hole open again giving me lines touching the side wood and I dice the port.

To glue up the ring, I bend the strips as close as I can and cut an angle on each end. Then those angles meet up they form a scarf joint it not perfectly flush. Clamping them together forces the ring into the boundaries of the hole in the plywood. It is hard to describe.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Having a hard time getting more than one picture in a post. . . This should be enough to give you the idea.


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_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Doing a rose like those Brad Combs linked to in another thread might be kind of nice for a sound port.

https://www.vihuelademano.com/rosesinvihuelas.htm

No binding on these. Just added a curved piece inside before closing the box, cut the ports, painted the edge black and sprayed clear on top

I did this one in a similar way to Bryan.



Sides bent, end blocks and linings in, port reinforcement in, back on, cut the sound port. The "secret weapon" was a set of long conical plugs (wooden) available from yacht chandlers as emergency bungs for failed hull penetrations (pipe outlets etc.). Something like these. You could turn up a similar cone on a lathe or even a drill press. The port can be sanded to perfectly round using a suitably sized conical plug wrapped with sand paper. The binding and purfling are bent to shape with diagonal end cuts to form a scarf joint. Apply glue and wedge in place with the same (waxed) conical plug/long cone. Give yourself plenty of depth on the bind/purfling so you can trim flush with the side curve inside and out. You can do the purfling and binding in separate stages if you want. I trialed this with the rope binding, but it looked a bit OTT, so I just kept it simple.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Perfect. Thanks for the response sir


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Looks great. I’ve had trouble getting it “clamped
Tight” to the parameter . Maybe a cone as T Gore has suggested would work


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I like the conical plug idea too. It would make it easier to ream out the veneers I put on the inside since I could use the same plug with sandpaper trick to get it nice and flush. That is hard to do with a cylinder.

_________________
Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I start by drilling a large hole in the end grain of a short piece of wood. I turn a 'spool' on the lathe, with the inside diameter the same as the hole I drilled. The spool is cut in half in the middle, and the two ends go into the ends of the drilled hole, with the flanges up tight against the eds of the piece. This gets put back into the lathe, and the outside is turned to a taper.

Once that's done I bend strips of veneer to go around it in a spiral on the outside, and glue them on, one at a time, with long laps. This avoids having a visible joint in one spot if you're lucky. I use Titebond, and wrap with strips of rubber to clamp them.

I use a large Forstner bit or a hole saw to drill into the side of the guitar, which has been reinforced on the inside with a cross grain piece, usually willow. The tapered plug is wrapped with sandpaper, and used to dress the sides of the hole to the correct taper. When the fit is good I spread glue on the plug and the edge of the hole and push it in; not too tightly, but enough to produce a thin glue line. When the glue sets the edges can get trimmed back and rounded over.