Custom inlays,
including photo
inlay.

The short version

Every inlay job is the same three steps, whether it is a quarter inch dot or a photograph buried under resin:

1. Cut an indentation.
2. Put something in it.
3. Fill the gaps with superglue or epoxy and sand it flush.

Past that, do not make it harder than it needs to be. Fancy or plain, it is the same job.

The numbers, in one place

Item	Figure	Note
Photo inlay cavity depth	~1/8″, or a hair less	Enough resin above the photo to survive wear
Wood left at the fret slot	1/32″	Then pared off with a razor or chisel
Or, the easier route	1/16″ to 1/8″ of board left	Shorter photo, no fret slots to recut
Casting resin catalyst	15 drops per ounce	At roughly 1/8″ pour thickness, check your product
Pre cut mother of pearl	Just over 1/16″ thick	Thin. Plan the radius around it.
Tightest radius for thin inlay	~12″	Tighter than that and you sand through at the edges
Inlay router bit	1/16″
Cavity depth	A hair more than the inlay	Room for glue underneath
Polishing sequence	220, 1000, 1200, 1500, buff	For resin. Plain fretboards stop around 220 to 320.
Leather dye dwell	45 seconds to 1 minute	Then wipe

Photo inlay

This is the one people ask about most, and it is more straightforward than it looks. It is a photograph glued into a routed pocket, sealed, and buried under a thick pour of casting resin that you polish up like a clear coat.

Preparing the artwork

1. Build a mock fretboard to scale in Photoshop or whatever image editor you have.
2. Drop your images into the marker positions on that layout.
3. Print on glossy photo paper with an inkjet. A laser will do if the quality is good enough.
4. Cut each one out and test fit it before any glue comes near it.

Routing the pockets

Rout the marker positions to about 1/8″ deep, or a touch less. The depth matters. Too shallow and the resin above the photo is thin enough to wear through, deform, and eventually expose the paper.

The fret slot decision

Two ways to go, and it is worth deciding before you rout anything.

Run the photo into the fret slot for the maximum image. You recut the fret slots afterward, and each fret then has one side seated in wood and the other in cured resin. It looks the best. It also means:

• The resin has to be fully cured, or frets push right back out of it.
• Cut the slots generously.
• Expect to need superglue on the frets that sit against resin.

Or leave 1/16″ to 1/8″ of board at each fret slot and use a shorter photo. No recutting, no frets fighting you, just a slightly smaller image. This is the easier route by a mile, and the one to take on a first attempt.

Gluing the photos down

Use epoxy. Five minute works. Fifteen minute gives you more working time and is probably the better call.

• Work three pockets at a time. Any more and the mix goes off before you have them seated.
• A good coat, not a heavy one, covering the base and the walls.
• Keep it off the top face of the photo.
• Watch for shed bristles from cheap brushes and pick them out.

Set each photo in gently, then press it down with something soft, like the end of a pencil. Every part of the photo has to touch the wood underneath it. That bond is the foundation the resin binds to. A poor one and the whole acrylic top can lift off down the road.

Why casting resin, and not the obvious alternatives

Both of the things you would reach for first, I tried, and both got thrown out:

• Superglue. Workable, but way too many bubbles.
• Epoxy. Bubbles again, and it dries too foggy over an image.
• Polyester casting resin. This is the one that works.

The pour

Build a dam along both edges of the fretboard with tape. I use Frog Tape throughout here, and it gives a noticeably better result than ordinary masking tape.

Run the tape so it stands a little proud instead of buckling inward. You want to sand back to flush, not find a hollow.

How much catalyst depends on your pour thickness. At roughly 1/8″, that came to 15 drops per ounce. Check your own product's instructions.

Fill each pocket to a hair more than flush. Then leave it. A few hours to set, and another day beyond that will not hurt anything.

Levelling and polishing

Treat the resin exactly like a clear coat, because that is functionally what it is, just a very thick one.

1. 220 grit with the radius block to take the excess down and establish the radius.
2. Wet sand 1000.
3. Then 1200.
4. Then 1500.
5. Buff.

You will be sanding wood along with the resin, and that is fine. The point is getting the scratches out of the acrylic. Keep the whole surface at an even height instead of working one pocket at a time.

Three ways to handle the edges

• Resin to the edge. The tops of the photos become visible from the side and double as your side markers. Not the most elegant thing you will ever see, but it works, and it means no separate side dots.
• A picture frame. A smaller image set inside each pocket with wood all around it. No edge finishing needed, and no fret slots to recut.
• Binding down the sides to cover the edge completely.

When frets will not stay put

This is the trade off for running the photo all the way to the slot. Frets seated against resin sometimes flat out refuse to hold.

The fix: clamp the frets down hard against the board with wooden cauls, then inject superglue from a syringe alongside each fret and let it run down the tang. Flip the neck and do the same from the other side. If glue comes through, you know it traveled the full slot.

You will be buffing again after levelling and crowning regardless, so a little extra work here is not fatal. But avoidable work is still worth avoiding.

Conventional inlay

Thickness sets your radius

Pre cut mother of pearl is just over 1/16″ thick, which is not much. The moment you radius the board, the outer edges of each piece lose material, and thin inlay near the edge of a tightly radiused board can go transparent or disappear on you.

Before or after glue up

You can inlay a loose fretboard, or one already glued to the neck and radiused. Doing it loose cuts down the consequences of a mistake, which is the reason for it here. Either is fine.

Working loose: mark the centerline, register your neck template to it, tape it down, mark the outline, bandsaw outside the line, then bring it to final size with a jointer or a bearing guided router bit against the template.

Routing the cavity

Router, Dremel, or an X-acto knife and a small chisel, whatever you can control. A 1/16″ bit does the work here.

Cut the depth to a hair more than the inlay thickness so there is room for glue underneath. A little deep you can recover, just top it up with superglue. Too shallow you cannot.

The fence

Straight cuts come from a fence, and a fence can be a broken paint stirrer stuck down with double-sided tape.

1. Set it so the router body rides against it along the line you want.
2. Check the distance from the fret slot to the fence is identical at both ends. That, and nothing else, is what makes the cut parallel.
3. Clamp it, then push and pull the fence to make sure it will not shift.

Straight sides get the fence. Curved sides are freehand. Go slow, stay shy of the scribed line, then creep up to it a hair at a time. It is a lot easier to take a little more off than to put any back.

Scribing

Set the piece down, hold it firm so it cannot move, and scribe around it with a sharp pencil or a fine marker. Watch how close you are drifting to the fret slots, because on some positions you will not have much room to play with.

Gluing it in

Plain superglue is plenty. It sets fast, and once it is wet sanded and buffed it matches the surrounding wood closely. Buffed at the end, the whole board blends together.

• Do not fill the cavity all the way. Put in enough that some escapes the sides as the inlay goes down.
• You have about a second of working time, so have the piece already in hand.
• Come straight back and fill any gaps left while they are still open. Wait, and the gaps are too fine for glue to get into.
• Accelerator locks it so it stays put while you move to the next one.

Sitting a little below flush is fine, less than the thickness of a business card. That small margin means that when you radius the board you are not forced to take so much off that the piece thins at its edges.

You can also dry fit every piece and glue them all in one session. One at a time is just easier to show.

When the cavity comes out too big

It is going to happen. How well you can hide it depends entirely on the wood:

• Ebony. Easiest by far.
• Rosewood. Manageable.
• Maple. Hardest. The lighter the board, the more a filled gap shows.

Option one: superglue and lacquer

Fill it with superglue, and a coat of lacquer later blends it in.

Option two: pigmented epoxy

Mix a black pigment, Master color, from luthier suppliers and cabinetmaking shops, into epoxy and bed the inlay into that. Sanded back, it reads as a deliberate dark border.

And if the pigment comes out blacker than the board, you will need to dye the fretboard to match, which is a perfectly normal thing to do.

Seating pigmented inlay

Watch for burrs in the cavity stopping the piece from bedding down. Slide it around and you will feel them. Clean them out first.

With epoxy squeezing up around the edges it gets hard to see whether the piece is straight, so scrape the excess back with a razor and check alignment against the fret slot before it cures. The smallest misalignment shows in a piece that small.

Check that neither end is sitting high, too. A high end goes thin, then transparent, when you level the board.

Five minute epoxy gives you very little time for all of that. Fifteen minute is worth the wait.

Dyeing the board

Black leather dye over the whole fretboard evens out the color and hides pigmented fill.

• It soaks into wood and will not penetrate mother of pearl, so the inlay stays clean.
• Leave it 45 seconds to a minute, then wipe.
• Sand back and re dye any spots where it crept somewhere it should not have.

Buffing after the frets go in pulls the whole thing together.

On method

Superglue or epoxy. Router, Dremel or chisel. Before glue up or after. What matters is that the piece sits flat, the gaps are filled, the surface is level, and the radius is true. Do those and the rest is just preference.