JB-4M fretless bass

I have been working away on my bass for about two weeks now.
I decided (bravely?) to try a challenging burst by hand. Red mahogany in the centre and a semi-dark black on the outside. I started by sanding for a few days. I never knew 320 and 400 grit for timber even existed before this project, although I've done mirror finish on steel by hand several times, most recently on an anvil of all things. Hey, don't get any fingerprints on my anvil! Anyways, I practiced with the stain on hardwood ply a few times before tackling the guitar. I found that with a mix of 1 part stain and 2 parts colour reducer you can actually move the location and blend of the burst with a reasonable amount of control. The mix of the black and mahogany even turned out to be a pleasant walnut brown colour. What I couldn't control at all was the parts of the timber that were too thirsty for the stain. These just stayed whatever colour you first applied. Overall, I think the final result is ok. Even if I just went with a single colour it would still look patchy because of the thirsty bits.
I'm going to leave the stain to dry for 4 or 5 days. I have gloss poly to finish the body later.
So, on to the neck. I'm planning on using Scandinavian oil on the back. It produces a fairly dry feel. Not sticky at all. What's the word on finishing the fingerboard? I'm assuming that I should leave it totally unfinished, particularly for a fretless beast. This being the first guitar of any sort I have owned I really don't know about these choices. Am I on the right track?

And now some pictures.
I'm very happy with the left-hand side of the burst. The right hand side is not as good. I got caught with the timber soaking up too much of the black stain. The top right will be covered by the pick guard. The bottom right will be visible. I think I can live with it. I applied all stain by hand with a rag. Using 1 part stain with 2 parts colour reducer gave me quite a bit of control over the burst. I probably put on about 20 coats of stain around the edges of the burst, finessing the colour, width and location each time. If you're going to apply a burst by hand, this seems to be the way to go.
I used Feast-Watson Japan Black and Maple colours. The colour reducer was also Feast-Watson made to suit these stains.

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The photos really don't do it justice.

Oh, and that's not the neck. It's just a stick.

I have a problem. When I fit the neck to the body I have a 2.5mm gap between the end of the neck and the body cut-out. The neck is pushed as far forward into the body as possible. The problem is that the curve on the neck doesn't match the curve in the body cutout. You can see in the photo that the top and bottom of the curves is snug but there is a large gap in the middle.
I don't think I can simply alter the curve on the neck to suit the body. I'm assuming that, because the neck is tapered, I will ruin the nice firm fit that the neck currently has. I can't think of any way of filling the gap that will allow me to match colours with the stain on the body. Do I just have to live with the gap??

Attachment 21508

Are you going to use a scratchplate? If so that would hide the gap and be more aesthetically pleasing. Something that would concern me is how secure the join is. If you were to bolt it in as is will it feel solid?

Failing that you might be able to fill the gap with a matching putty. Shaving the neck would be a last resort in my book as not only would it be arduous but might give you intonation issues.

Very good point you made there. I am using a scratchplate and it covers the gap entirely. At the moment the neck is a nice firm fit in the cutout so I definitely won't alter it. Thanks!

When the first coat of stain had dried, I noticed that the body had 5 significant "pimples" on the surface. These protruded about 1mm above the surface. Because I needed to sand these back, the stain in these areas was of course removed. So, I re-stained the whole body. The stain is now a bit darker than I planned, but it's very nice and even. In the end, I'm happier with the re-stain than I was with the original attempt.

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I've finished shaping the headstock. I based the design on the Music Man Bongo. I put a full write-up and a link to my template on the Headstock forum. The post is HERE:

And here's a picture:
Attachment 21593

I quickly decided to coat the fretless fingerboard with epoxy. After only a few minutes playing, the strings were leaving marks on the fingerboard. And yes, they were flat-wound strings.
I used a marine epoxy that I found on eBay. It's a 2:1 mix that is classed as ultra clear, sets very hard, gives you a good few minutes working time and flows fairly slowly.
There's lots of advice on the internet about creating a "dam" around the edges of the fingerboard to prevent the epoxy from flowing off the sides. I found that this was not needed. If you pour the epoxy on steadily, it is so thick that it won't flow off the sides. Its own surface tension holds it in place at the edge. This produces a fantastic glossy surface on the epoxy without any sanding or polishing. It is however perfectly flat. In fact, if you elect to have a completely flat fingerboard, it even leaves a nice smallish radius at the edges so you don't even need to touch the epoxy with sandpaper.
Anyway, I didn't want a flat fretboard, so I got out my radiused sanding block. I put the radius back on the fingerboard with 160 grit, then used finer grades until I had a flat sheen. Then out with the polish to get it really shiny.

Raw poured-on epoxy
Attachment 22904

After shaping
Attachment 22905

After polish
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'Slippery when wet' :)

Nice! Very well done.

Niiiiiiiiiiice.

looks great Nathan, the fingerboard looks great with epoxy. Love the headstock shape too

I'm loving everything I'm seeing! Keep at it!