My first build: left-handed JM-1L

[jarro_2783]

Sorry I said half a cent, I meant 50 cents, half a semitone.

[Simon Barden]

Half a semitone is a lot to be out. First, are you sure you intonated at the 12th fret (using the 11th or 13th has been done before). The nut being high can mess things up a bit but not normally by that amount. And the frets would have to be a long way out of position to be that far out, and they don't look it.

But the kit strings are utter rubbish and of variable thickness and output and are only good for basic set-up like action and nut slot depth when you are taking them on and off a lot and it saves spoiling a good set of strings. Always do the intonation with a good set of strings fitted.

To adjust the nut, you either need a set of nut files, or you need to remove the nut and sand the bottom down and put it back again. (and repeat until the nut is at the right height). Good nut files are expensive (a worthwhile investment if you work on several guitars though), so filing down the bottom of the nut is the normal route without them.

Tapping lightly from either end using a hammer and a largish flat blade screwdriver is my normal method of nut removal. they should be help in by a smear of PVA glue which stick well to the wood but not the plastic. You can also tap lightly from the headstock side of the nut, but don't tap towards the headstock as it's very easy to break off the end of the fretboard holding the nut in place.

You'll need to clean out the old glue from the slot. I normally use a mixture of a sharp blade and a needle file.

I wouldn't glue the nut back in place until you've done all your set-up adjustments and are 100% sure the nut is the right height. String tension will keep it in place and I normally loosen the strings off, smear the nut bottom and the slot sides with a little PVA or Titebond, slide the nut back in press it down, remove excess glue with a wet cloth or paper towel, then replace and tighten the strings to clamp the nut in place whilst it dries. Just make sure the nut is centred properly so it's not sticking out of the slot on one side of the other - but you should find that the strings centre the nut on their own.

[jarro_2783]

Thanks, adjusting the nut doesn't sound as hard as I thought it would be. How do I decide what height the nut should be?

For reference here is how high it is now:


If you can zoom in it looks like it's just over 3mm to the bottom of the string.

Another question, I had the bridge up around 5mm from the body and the strings were still touching at the bottom of the neck, even with the saddles quite high, any ideas what could be wrong there?

[Keith Walters]

I've only just noticed this thread.
I've built a left-handed Jazz Bass and a left handed Strat.
Both of them had badly aligned neck mounting holes, and both had Log-types pots wired back to front, which basically magnifies the problems you have with linear pots.
As far as I know, no other manufacturer of Left Handed guitars does this, so I don't know where they got that from.
Regarding the tremolo claw mounting screws, I found the ones that they supplied with the Strat kit were totally unfit for purpose. Maybe the original Fender screws they copied from just aren't good enough for the softer basswood.
I substituted some much thicker stainless steel screws from one of those "handy hardware" packs I bought at Aldi.
I ground the head diameter down with my bench grinder and they fitted nicely.

I followed the setup instructions on Fender's website and it just doesn't go out of tune.
I understand that main source of problems with those is simply people not setting them up correctly.
I went to the trouble of making up a wooden strain relief block for doing string replacements, and it's quite easy if you know what you're doing.
I don't actually use the tremolo arm much, I just like the sound you get from a floating bridge.
And yes, it took me a while to work out how the bridge is fitted. Basically it balances on "tiptoe"

[Simon Barden]

I use nut files, so cut down rather than sand the bottom of the nut, and I also cut down using my eye and experience as to the right height (and often cut too low so I've got a good stock of spare nuts). But I'd use feeler gauges to measure the height of the first fret, and add 0.4mm on top of that. The base of the nut needs to be sanded down so the nut slots are that distance from the fretboard. Just use the two E string slots, the rest will take care of themselves.

That will give you a reasonable string height over the first fret, but you can probably go a bit lower if you want. But don't take it lower before you've got the action and neck relief sorted out.

As to the bridge height, what sort of neck relief is there? I'd start off with the neck set flat, as string tension will add some bow to it, raising the strings up slightly.

Are the body neck screw holes big enough to just pass the screws through without them binding on the sides and needing screwing down? They should only screw into the neck itself in order to fully pull the neck flat into the bottom of the pocket. If you have to screw through the body and neck, there's a good chance that the screw can't turn further because its all the way into the body, but there's still a gap between the neck and the body. This gap will change the neck angle and if it's at the body end of the pocket, will raise the neck angle requiring a higher bridge position.

Also check for any splinters or other small objects in the neck pocket. It doesn't take much for the neck not to sit flat and change its angle.

Once you get the neck flat and it seated properly in the pocket, then run a long metal straight edge along the neck and see how much height there is between it and the body at the bridge position. A photo of the bridge alongside a ruler would be nice to get an idea of how tall it is.

As has been said by others, the 2-point bridges are a bit different to the vintage 6-screw types, and the bridge plate does sit a bit off the body, allowing it to float. But maybe 2-3mm rather than 5mm off. But you can also raise the individual saddle heights as well.

If the neck angle is very wrong and the bridge needs to go very high, then the options are 1) put a shim under at the neck end of the pocket (easy to do) or 2) modify the pocket or the neck heel to adjust its angle (harder). I'd always suggest doing 1) first to work out how big an increase or decrease in angle you need. I normally use a 10mm x neck width piece of veneer as a shim, though any hard material will do. A shim at the body end of the pocket is invisible, but any sizeable shim at the neck end of the pocket will be visible, so you may want to think about altering the heel angle or pocket floor angle instead.

Just realise that a small shim has a much larger effect on the neck angle than you may think. Depending on the neck pocket length it's between a 4:1 or 5:1 increase, so a 0.5mm shim can lower (or raise) the string height at the bridge by 2mm-2.5mm.

[dozymuppet]

Love that headstock shape.


Sent from my Pixel 4 using Tapatalk

[McCreed]

Hi jarro.
I also use nut files for all my nut action adjustment and have a slightly different approach than Simon but his advice is solid.
Presuming you don't have nut files, I addressed the issue of nut height adjustment by sanding the bottom of the nut in another thread recently, and being lazy, I've just copied & pasted the reply I posted there:

re: the nut, yes, you can adjust it from the bottom. You need to be careful to not sand an angle in the "front to back" direction.
You may wish to put a slight angle on the E to E direction so that the bass E is higher than the treble E.

When you sand, don't do it freehand. Use a block that you know to be flat, placed on a bench/table and put the sandpaper on that working the nut across the sandpaper. A plate of glass makes a good flat surface for doing this, and you can sticky tape the sandpaper so it doesn't slide around too.

When you measure the nut action, you want to depress the string at the 3rd fret and measure the clearance from the bottom of the string and the 1st fret. Since you won't be adjusting each individual string height, just measure the two E strings presuming the nut slots are radiused from the factory. The best way to measure this is with feeler gauges.

As a rough guide, you want the bass E to be .010" - .008" and the treble E .006" - .004" (at 1st fret, string depressed at 3rd).

FWIW, I just measured one of my strats with a 2-point vibrato on it, and the bottom of the bridge plate is 3mm above the body with the fulcrum points and "knife edge" adjusted accordingly. I have the spring tension adjusted so the bridge plate is parallel to the body (I also have a stop shim, but that's not relevant here). My string action is right where I like it - bass E: 1.75mm and treble E: 1.5mm at the 17th fret.

As Simon has pointed out there are a number of ways to gain or lose a couple mil if needed, but I would check all the things he mentioned first and not get too hung up on it in this stage of the build. I don't think it's anything that can't be addressed in the final set up. That's one of the good things about screw-fixed necks, you can always take them off to make adjustments or modifications.

[jarro_2783]

Thanks all, I'll play around with the nut first, and it looks like I have more saddle adjustment room than I thought. Pushing the string down at the 3rd fret there is definitely more than 1mm just eyeballing it, so I'll start there.

A couple of other problems: I keep breaking the wires at the solder points, I'm going to run out of wire at this rate, so I'll have to find some more to extend it, some of that shrink wrap I bought years ago might help here too. I also plugged it in to see how it sounds and ironically the humbucker makes the most buzz. The volume pot is also buzzy when it isn't on full.

[Keith Walters]

Thanks all, I'll play around with the nut first, and it looks like I have more saddle adjustment room than I thought. Pushing the string down at the 3rd fret there is definitely more than 1mm just eyeballing it, so I'll start there.

A couple of other problems: I keep breaking the wires at the solder points, I'm going to run out of wire at this rate, so I'll have to find some more to extend it, some of that shrink wrap I bought years ago might help here too. I also plugged it in to see how it sounds and ironically the humbucker makes the most buzz. The volume pot is also buzzy when it isn't on full.

Buzz is more likely to be coming from devices like LED lights or TV sets on standby.

I have a 40" LCD TV mounted above my workbench and I have to turn that off at the power point if I want to work on audio equipment.
The easiest way to track down sources of interference like is just with a portable AM radio tuned to a distant station.

[jarro_2783]

I do have a large fluoro directly overhead, maybe that did it.