Short-scale fretless electric bass

[Drew Stephenson]

I don't have any feeler guages to hand but looking at my upright I'd estimate the gap from the bottom of the string to the fingerboard to be about 1/3mm.
Give or take.

[Funkyflash5]

As a guide to learning intonation, automotive pinstriping tape can be applied across the fingerboard as a mock fret line. It's thin enough to be relatively accurate and peels off cleanly when no longer needed. It's how I was taught upright bass.

[Martin Walker]

As a guide to learning intonation, automotive pinstriping tape can be applied across the fingerboard as a mock fret line. It's thin enough to be relatively accurate and peels off cleanly when no longer needed. It's how I was taught upright bass.

Oh wow, thanks for that tip Funkyflash5

I was determined to end up with an unlined fretboard this time, but your suggestion is very welcome indeed until my muscle memory kicks in. I think I'll go for 2mm pinstriping tape, as that is about the width of a fret. Oh, and Wonks was definitely right about me needing a side dot at fret 1, but I'll see I get on with temporary automotive pinstriping tape first.

On that note (pun intended) I've also this morning come across another fretless intonation decision to be made - do you set up the bridge so that for accurate tuning your finger is placed just behind the imaginary fret (i.e. where your finger would be on a fretted bass - that's the way my bass was set up at the factory), or dead centre over the imaginary fret marking.

I hadn't thought of the latter possibility until viewing this YouTube video this morning, which declares that the latter approach give better intonation right across the fretboard:

https://youtu.be/cEnd3Szjf6c?t=341

As I'm currently finding my eyes want my fingers pointing exactly over the side dots, I think I'm going to move the bridge close towards the tailpiece to achieve this. Any thoughts from other fretless players?

Martin

[BigRedX]

Since there aren't any frets, the lines are only there to get you to roughly the right place and the whole joy of fretless is that gives access to all those in between notes (as well as removing the tuning compromises caused by frets in the first place), setting the intonation really doesn't matter.

On a bass like yours I'd get the angle of the bridge so that E and G are roughly in the right place and leave it at that.

Remember also that on the higher "frets" the dots are going to be subject to parallax.

[FrankF]

One of the comments from Scott's YT clip (as linked by Martin):

"For me, vibrato on a fretless means you are in tune at least some of the time.".

I'm wondering how difficult it is to remove the frets yourself, if you decide to buy a fretted shortie, for example. I'm sure I saw someone on YT using a soldering iron to warm each fret up, then just pulling them out with needle-nose pliers. Is it as easy as that? And, aesthetics aside, is it viable/playable to just leave the slots unfulfilled?

[Martin Walker]

One of the comments from Scott's YT clip (as linked by Martin):

"For me, vibrato on a fretless means you are in tune at least some of the time.".

I'm wondering how difficult it is to remove the frets yourself, if you decide to buy a fretted shortie, for example. I'm sure I saw someone on YT using a soldering iron to warm each fret up, then just pulling them out with needle-nose pliers. Is it as easy as that? And, aesthetics aside, is it viable/playable to just leave the slots unfulfilled?

When I removed the frets from a 60's Hagstrom bass guitar it was easy - I just gently tapped them out sideways using a nail punch.

However, many modern guitars have fretboards with bound edges, so I believe you have to lift the frets out vertically with a special tool, and that can be more prone to fretboard damage, especially if the frets have a 'tang'.

You could certainly leave the slots unfilled, but it's easy enough to fill the slots with your choice of coloured strip, to leave a tuning guide.

[BigRedX]

It's best to invest in a set of proper fret pulling pliers to do the minimum amount of damage to the fingerboard. The wood used for the fingerboard will determine how successful this process is. Some will be better than others. Heating up the frets works because it causes the slots to enlarge slightly which means less damage to the ends of the slots.

The whole point of fretless is the smooth fingerboard. That means you need to fill the slots left by removing the frets and repair any damage caused by pulling them out. If you want the lines to be visible use either contrasting wood or wood filler. If not pick something close to the actual colour of the fingerboard.

You may also need to level and re-radius the fingerboard after removing the frets as this is much more critical than on a fretted instrument, where any small bumps and imperfections in the surface are disguised by the frets.

Edit: The frets on modern instruments are often glued as well as hammered in, and even on an unbound fingerboard the tangs of the frets will have been shortened to allow the sides of the slots to be filled to hide them.

[Wonks]

You warm the frets up with a soldering iron in case they were installed using glue, and that helps to loosen the glue's grip on the tang. So the fret should come out without risk of taking some fingerboard with it.

As to removing the fret, it should come out the way it went in.

Some frets (at least in the 60s) were installed from the side, so should be knocked out that way. Maybe Martin got lucky when he defretted the Hagstrom. I'm not 100% sure how you'd tell, but there will probably be tell-tale marks in the wood at the fret-ends.

Otherwise the correct tools to remove frets are pincers that have been ground flat at the ends. The idea is that the pincers grip the fret itself which is then pulled out, and aren't used to get under the fret to lever it out. It's not a good idea to use needle-nose pliers as they are far more likely to slip and for you to damage the fingerboard. And if the frets are well seated and griping the fretboard, you'll need more of a hold on the fret than the small grip area that needle-nose pliers will give.

It's not a good idea to leave the fret slots unfilled. For a start you'll start to wear the edges of the slots where you are pushing the string down on them a lot quicker than the rest of the fingerboard.

But the fingerboard, as part of the neck, is under compression from the strings. Leaving the slots empty prevents a lot of the fretboard from being part of the compressed neck area and so helping to spread the load. As a result, the load-bearing cross section of the neck becomes smaller and puts more strain on the rest of the neck, making it far more likely to develop a bigger bow in it over time and possibly to twist over time as well. Even a softwood fillet, if glued in well, can add strength back in to the fretboard under compression.

Extra bow can normally be compensated for by the truss rod, but the truss rod is then also pressing harder against the fretboard. Leaving the slots unfilled makes areas of the fretboard weaker and there is always the chance of the fretboard cracking along a slot line.

If the rest of the neck is of strong construction (especially if a multi-laminate), then you may never see any ill-effects, but it really is much better to fill the slots than leave them unfilled.

Edit: As Big Red X says, it is a good idea to go over the fretboard with a suitable radius block after defretting and then filling the slots. It's surprising how uneven some fretboards are.

[Martin Walker]

Edit: As Big Red X says, it is a good idea to go over the fretboard with a suitable radius block after defretting and then filling the slots. It's surprising how uneven some fretboards are.

I suspect that might explain why my D string needed the truss rod slackening off a little more, to avoid the string buzzing at the 3rd fret position and below, while the other three strings were already totally buzz-free.

[Wonks]

It may also have been that the bridge radius doesn't quite match that of the fretboard. In theory it should be very slightly larger radius.

Had you had a bridge with individual saddles with string height adjustment, you may have just needed to raise the D-string saddle a touch.

Or it could be a mixture of both.

[Martin Walker]

Had you had a bridge with individual saddles with string height adjustment, you may have just needed to raise the D-string saddle a touch.

Yep, that would have been the easiest solution

[Albatross]

Maybe just raise the bridge so its right for the 'D' and then if necessary file down the other saddles to get the radius where you want it.

[Martin Walker]

Maybe just raise the bridge so its right for the 'D' and then if necessary file down the other saddles to get the radius where you want it.

That's a possibility, although since the buzz only occurred across the first three frets of the 'D' string, I suspect leaving the bridge heights alone and instead lowering the nut slots of the other three strings would give me a lower overall action without re-introducing any buzzes.

[Martin Walker]

OK, thought I'd report back a week alter with a progress report.

On Saturday afternoon I successfully filed down the nut slots so that each string ended up just 0.4mm above the fretboard, by placing a cardboard bookmark (thickness already measured with a digital caliper) at the top of the fretboard, and then continuing to file carefully until marks just started to appear on it. You can see these marks below - it worked well

I was originally going to buy a cheap set of nut files, but most were intended for lead guitars and didn't reach the .045, .060, .080 and .095 diameters of my strings, so I instead used conical swiss files, after carefully masking with tape the point at which they reached the diameter of each string, so I didn't go beyond that. The action is now a huge amount lower at the top, easier to play, and still no buzzing at all at any position. I slightly tweaked the bridge position so that the octaves were exactly 'on the side dots', and checked the intonation.

I do intend at some point to mod the electrics, as the Hofner Bass design is notorious for being carried over from a standard guitar, and thus most confusing, particularly on this Harley Benton model - 'Bass On' switches on the bridge pickup, while 'Treble On' switches on the neck pickup, while the 'Rhythm/Solo' switch is largely redundant on a bass (it switches between 70% and 100% volume)

One final query for my guitar expert friends - the amaranth/purplewood fretboard has always had various white 'grain' marks, particularly at the top (see photo below). I've just placed an order for some Rotosound lemon oil (yes, I know to use it sparingly) to 'feed' the wood, but is this what I should be using to make these white marks less visible? (It's not sawdust left during manufacture, nor nut slot dust during my filing, as I've tried brushing the white marks out with a stiff brush, and wiping the fretboard with a damp cloth).

Many thanks for your help, advice and enthusiasm during this thread!

Martin

[zenguitar]

I wouldn't worry overmuch about the white in the open grain. But if it bothers you I would suggest a toothbrush and a suitable liquid. White Spirit is always safe on bare wood and I would be happy to use volatile liquids like meths and isopropyl alcohol that would evaporate away quickly.

Andy

[Wonks]

You'll probably find that the lemon oil alone will remove it, but again a soft brush might help get in right down the crevices. It's probably just dust left over from the polishing process. An old toothbrush and a vacuum cleaner will probably get most of it off if you fancy trying that.

[Kwackman]

most confusing, particularly on this Harley Benton model - 'Bass On' switches on the bridge pickup, while 'Treble On' switches on the neck pickup

That is confusing, the other way round would make more sense?
I hadn't seen a guitar where the writing is upside down before, but it makes sense as the player is always looking from above!
So, does "on" on those 2 switches mean "up" - towards you, or "down", away from you.
Nice job on the nut

[Wonks]

You'll find the switches are mounted on a PCB behind that control plate, so it's not a simple job to swap the connections over. You'll be cutting PCB tracks and doing a lot of hardwiring, unless you replace the control plate with one of your own and put some more logical controls on it.

I also think you'll find that if HB have used the same parts kit as the kits Pit Bull sell use, the soldering on the PCB is terrible, and there are switch solder pads that aren't soldered up to save a couple of blobs of solder, and so fail to provide extra mechanical fixing for the switches.

[Martin Walker]

most confusing, particularly on this Harley Benton model - 'Bass On' switches on the bridge pickup, while 'Treble On' switches on the neck pickup

That is confusing, the other way round would make more sense?
I hadn't seen a guitar where the writing is upside down before, but it makes sense as the player is always looking from above!
So, does "on" on those 2 switches mean "up" - towards you, or "down", away from you.
Nice job on the nut

Thanks for vote of confidence on the nut slots kwackman

The neck pickup is on when the 'Treble On' switch is down (away from you), while the bridge pickup is on when the 'Bass On' switch is down. At first I found this so confusing that I was sure it was a wiring error at manufacture, and that I could simply swap the two pickup cables over on the switches (I wanted to get the the guitar as playable as possible before investigating behind the control plate).

However, as Wonks has now confirmed, I'm pretty sure now that it will be a PCB under there rather than hand wiring, so a more radical approach may be required. At present I just leave the 'Rhythm/Solo' switch permanently in the louder towards me 'Solo' position, both pickups 'On', and just balance them using the Volume 2/Volume 1 pots. In other words, I'm totally ignoring all three switches.

This isn't Harley Benton's fault, as the Hofner Violin Bass has always had odd controls (Paul McCartney apparently only ever used the neckup pickup), but those labels used to make a little more sense - here's a description of the original wiring (from https://www.talkbass.com/threads/how-to ... s.1316113/ )

Stock Wiring:
The stock switch functions are as follows: Rhythm puts two resistors in series with the output signal, reducing the volume to 70% of full; Bass On puts a .1 uF treble cut capacitor in series with an 8.2K Ohm resistor parallel to the neck pickup (the resistor in series prevents the tone from being 'turned down all the way,' which reduces or eliminates the resonant peak and leaves a little more treble intact) and also switches the bridge pickup out of the circuit; Treble On puts a .01 uF capacitor in series with the bridge pickup (a capacitor wired in series cuts bass) and also switches the neck pickup out of the circuit. Everything up ('off') is bypass (no capacitors affecting the pickups). Because of the 'equal and opposite reaction' switch wiring, pickup blending is only possible with the pickups bypassing the capacitors, which is one of the biggest limitations. And the volume reducing Rhythm setting doesn't seem particularly useful.




However, if I pull both pickup switches towards me, there's total silence, so I assume Harley Benton have abandoned the capacitor/resistor networks, so the labeling becomes totally illogical

I have seen one clever violin bass mod that rewires two different value capacitors to the 'Bass On' switch, to provide two switched high end tone roll-offs, with 'Rhythm/Solo' switch used to switch your chosen roll-off in or out of circuit (discussed by its creator in the same talkbass link above).



However, like Wonks, I'm now considering making a new panel of my own, with two volume pots and a central tone pot, abandoning the three switches altogether, and keeping the original intact in case I ever want to sell on the guitar in original condition.

Martin

[Martin Walker]

Thanks for your 'white marks' advice zenguitar and Wonks - I think I shall set to with a toothbrush and vacuum cleaner before applying any lemon oil, although these are only minor cosmetic blemishes.