After you have cut your fret sloths (for fretted instruments), the next step is to get started on your inlay. There is a wide selection of choice on inlays in shapes such as block inlays, shark fin, stars, birds etc. and you can of course also make your own unique design and skill yourself in the art of inlaying.
A good starting point and widely used for good reasons is a dot inlay. With dot inlays you also have a variety of materials, colors and diameters to choose from and you can play around with the alignment on the fretboard and design a specific pattern. Most commonly positions are at the center or aligned left in the positions 3, 5, 7, 9, 12, 15, 17, 19, 21, 24 with double dots on the 12 & 24 to mark the octave.
Drill the hole
Once you designed your pattern and measured the positions, mark them with a pointer and drill a hole, either by hand, with the electric drill or a column drill if you have one. You can use a (slightly) pointed wood drill and select the corresponding diameter to your inlay dot.
Preferably, you don’t want to have the point of your drill going through the fretboard, although it doesn’t really matter as you can will be gluing it to your neck anyway, but still try to avoid it. Measure the thickness of your dot and try to set that as your goal for the depth of your drill. Keep in mind that you will still need to do your radius and that you will lose more depth from the sides of your fretboard, so you need to make sure that even after radius sanding, the whole of your inlay is still visible. This will not be an issue for the mid-section of your fretboard.
For my own projects, I usually drill the holes, than radius my fretboard and recheck the depth of the holes before putting in the dots.
For the actual gluing, place a good drop of medium instant glue in the hole and put your inlay dot in place applying slight pressure. Be careful not to glue your fingers together, we've all been there, so keep some debonder within reach. Once the glue is set, you can start or finish your radius.
- Your inlay is slightly too deep:
You can use a drop of instant glue or epoxy to top it off. It gives an extra shine to your dot, so cover all your dots. Sand any access back with your radius block and fine sanding paper.
- The hole is way too deep:
Better fill it up to the required depth with a mixture of saw-dust and wood glue & flatten the surface with a rod when the glue is still wet. Once the glue has fully set, measure again and re-drill the hole by hand if required. If you forgot to check the depth and already glued in your inlay, than you can consider to glue an inlay on top of the other one. Remove excess with your radius block.
- The hole was not deep enough and part of the dot disappeared with the radius:
Yes, s*** happens. No other option than to drill it out. Find the center point of the dot and mark firmly with a pointer. Take a small diameter drill and make a slightly bigger center hole so that your wood drill will have enough grip. Clamp the fretboard and drill at a 90 degrees angle till the required depth, which means at this stage that the bottom part of the inlay dot must full fit in the new hole. Glue the dot in place and remove excess material. You can consider to focus first on the dot itself with a fine file till you almost reached the level of your radius and then switch to your radius block.
- The hole is too wide:
If it is way too wide, you can best fill it up with a mixture of saw-dust and Titebond quick and thick. This glue dries clear and does not alter the color of your saw dust noticeably. Let it dry, re-measure, and re-drill with a smaller drill. If you just have a small gab, you ca consider to glue in your dot. Once you have done your radius with coarse (80 grit) paper and any excess inlay is leveled with your fretboard, you can place a drop of wood-glue on the dot and move over it with fine sanding paper, working some sanding dust in the gabs. Complete your radius with your radius block and the next step sanding paper (120 grit, or even already 240 grit).
- The inlay doesn’t fit:
sometimes a few well aimed and gentle but firm tabs with the soft side of the fret hammer will do the job, but if it doesn’t fit, it doesn’t fit. Don’t use too much force. Remeasure the diameter of the inlay dot, the hole and the drill. Maybe you need a bigger diameter drill or a smaller dot? If it is just a tiny bit off, than you can try to widen the hole slightly by moving the drill in the hole around the edges, like stirring it. This