I would like a fretless bass guitar, and I am considering giving an old bass a new lease of life as a fretless instrument.
I would like to know how to go about achieving this at home, by myself, to as high a standard as possible, for as little cost as possible.
When converting a fretted instrument to fret less you have a couple of options if you want to DIY:
Modify the current fingerboard in some way. This includes purchasing a fret-puller like @ekaj suggests, pulling out all the fretwires, and filling in all the fret slots with wood putty. Unfortunately you will suffer from the issues that @Alex mentions in that the entire neck will react much differently to changes in relative humidity and temperature--so you are left with a more brittle instrument. This is probably the cheapest option, but has the most risk.
Purchase a new, fret-less fingerboard and install it on the old neck. This is a little more involved than the previous strategy. Start off with visiting your local luthier or find a company that sells raw fingerboards. Warmoth may do it but I haven't asked them. Describe to your supplier the specifications of the neck you want--scale length is irrelevant because we don't have any frets :D, but radius and fingerboard wood are good things to start with. Get them to send you a new fingerboard to your specifications. Once you have the new fingerboard, remove bindings if there are any on the neck, and then you can remove the old fingerboard by using a fingerboard iron or similar tool. You could perhaps achieve the same thing with a very hot hair dryer or even a clothes iron set to very low levels. Once you heat the glue up all you have to do is slide a knife in between the neck and the fingerboard to break the glue bond. Move slow, and in sections and it'll be off in no time. Glue the new one in using some hide glue and clamp it tight for 24-48 hours. This option will set you back the most in cost of tools, labor, and time spent--but it's good experience if you ever wanted to get into luthier work. All this is assuming, of course, that your bass has a fingerboard glued onto the neck. If the neck is a solid piece move on to option 3.
Purchase a new, fret less neck. Finally, you can save yourself a load of trouble by cruising over to Warmoth's site and purchasing a new fret less neck. They more or less sell necks that will fit any bass's profile--and if they don't have one to fit yours then can make one. The only important thing is to line up the neck correctly pocket for installation. This would be your middle of the road economic option, and my recommended one.
That's it, and good luck!Tweet