curtisa

A couple of observations: Volume pot is missing its ground connection on the right hand lug. Assuming your diagram is showing the pots viewed from the back the tone pots are wired back-to-front - move the connection on the outside lug of each to the opposite (as yet unterminated) side. Passing Lane switch has a cap across the top pair of lugs - should be a straight wire link. Extra cap on the lower tone pot between the case and earth should be replaced with a straight wire link. Neck pickup hot lead is tied directly to the volume pot via the common tab of the 5-way switch. It will always be active irrespective of the 5-way switch position. Should be moved to the next lug up if you're after proper selectivity of the neck pickup. The only caveat as far as I can see (maybe this is already known to you) is that the bridge tone control will affect middle pickup when in bridge+middle position. Likewise, the neck tone control will affect middle pickup when in neck+middle. Only time middle pickup will be unaffected by tone controls is when it is selected by itself (position 3). The super switch is definitely the easiest way to achieve your requirement of middle pickup -> bridge tone control without the signal leaking into the bridge pickup when in position 1. Perhaps you can get one from your local music store? They're fairly common replacements for Yamaha and Ibanez super strats.

Diodes won't have the "signal steering" effect you're after. Essentially they are a one-way valve, allowing current to pass in a single direction only. The signal output of a pickup is bi-directional, partly spending its time "pushing" in one direction and then turning around and "pulling" back the other way. If the pickup signal didn't alternate between push and pull we wouldn't hear anything. Diodes also have a threshold that must be overcome before they will allow the flow of current - roughly 0.7V for silicon (as Prostheta suggested above), 0.3V for germanium, 0.2V for schottky. In comparison most pickups will only have an output of around 0.1 - 0.5V depending on how hard you're playing. Placing the diode on series with the pickup would probably result in no sound (or extremely weak, distorted sound). Diode in parallel (ie, between pickup hot and ground) might be interesting, probably introduces some mild overdrive depending on the type of diode you use, and is probably what's inside the Black Ice blob. Guitar pickup signals are dumb and need to be told what to do by mechanical switches. Asking them to perform acrobatics with diodes will usually result in unexpected (but possibly happy) side effects.

Unless I'm not understanding your query, according to this position 3 is already your Telecaster neck + bridge in parallel option.

Yep. An on-on DPDT (ie, two positions) is the only switch that will work in that drawing. Nope. You shouldn't need to change anything with the bridge pickup or bridge plate.

A quick scout of the interwebs indicates that Scott's 4-way blade switch is the most common way of doing it, probably because it's simpler and saves you having to drill an extra hole in your control plate. Found this after a bit of rummaging, but it also requires you lift the ground of the neck pickup cover and re-wire it separately. It's shown as a push/pull pot, but you can substitute your mini toggle for the "block" hanging off the tone pot as drawn. Note the caveat on the usage of the series/parallel switch (ie, pickup selector defeated when pickups in series). Note also that the thin black line going from the upper-left connection of the push/pull, all the way around the outside of the controls, to the lower left of the push/pull is not a wire, as I mistakenly thought on first look - It's just the edges of the control plate when viewed from behind!:

The bigger the cap value the duller/darker/warmer/<insert suitable adjective here> the sound when rolling back the tone control. Smaller caps remove less highs than bigger ones. Generic caps are cheap - grab a handful from your local electronics hobby store and try them out to see which ones work best for you.

The problem is that the OP wants to run each output into a separate amp, each probably with its own grounded mains inlet. Normally the only way to earth via a guitar cable is via your amps' earth pin on the AC line plug, and usually results in noise-free operation. Ideally if you have multiple paths to earth then each earth location will be at the same potential. In reality this isn't the case and the difference in potential of each earth can result in current flowing between them, and is evident in audio circuits as a loud 50Hz or 60Hz hum. If each pickup has its own earth via its own amp then no ground sharing can occur and hence no chance for a ground loop hum. As soon as you tie all the pickup earths together you've created a parallel path for each amps' earth through the pickup grounds in the guitar. Whether it actually results in hum is unpredictable and depends on many external factors - how good your amp wiring is, the quality of the guitar leads you're using, how low the impedance is of your amps earth bond, whether the amps are plugged into sockets at opposite ends of the room... Players who like to run one guitar through multiple amps are familiar with the issue of ground loop hum. It's the same problem as running three pickups through three amps with the pickup grounds tried together. There are ways around it with careful planning of mains earthing and external ground loop isolating transformers on signal lines, but if you're building a special guitar with independent outputs it makes sense to try the low cost solution first before resorting to the expense of external fixes. There's lots of good write-ups regarding ground loops with multiple amps. Rane did an excellent (if a bit wordy) application note on shielding and grounding in audio systems.

You may get lucky by simply common-ing all the grounds together. Try it both ways (grounds split/grounds tied) to see which one works best for you. Ground loops can be sneaky buggers. Tying all the grounds to the bridge in the guitar may be better for controlling the buzz you get by not touching the strings, but at the expense of creating the potential of a ground loop between the three amps. Separating the three pickup grounds and grounding the bridge via only one output as I suggested above will eliminate the potential for a ground loop hum, but may make two of the three pickups more prone to "hands-off-the-strings" buzz.

3/4" square trussrod is pretty large, and doesn't leave an awful lot of wood in the neck to carve without risking hitting the channel or ending up with a structurally unsound neck. I'd be tempted to scrap the neck outright and restart from scratch with a lower-profile trussrod. The typical dual action rods that get used a lot by guys here are only 1/4" square and are more than adequate to withstand the tension of a 4 string bass neck.

For best noise performance three separate grounds for each pickup system are required. Care should be taken to ensure none of the grounds within the guitar are mixed (hint: watch out for "sneaky" connections, such as between pot cases via the cavity shielding if the usual practice of earthing a pot case is utilised). The ground connection to the bridge/strings and cavity shielding should be tied to only one of the three pickup grounds - shouldn't matter which one you pick. Note that it's not electrically unsafe to mix the grounds, just that it can be a recipe for a ground loop hum between the three amps you're connecting to. Easiset way to consider it is as three independent guitars in one common box.

I find stepping away for a while with beer in hand helps calm the nerves Is making a decorative stripe the full length of the neck (think Fender skunk stripe) out of the question? Would probably look neater and more deliberate than a small patchup job in one region of the neck. However, if the trussrod channel is routed too deep the full length of the neck it may continue to reveal issues as you carve more... Alternatively, sometimes you just need to cut your losses and start over. I'm having to do the same for a neck on one of my previous builds. I just made a poor choice on the timber for the neck and now it warps and twists around like crazy in colder weather. It happens sometimes, but it can be cathartic to start afresh. The body wings in your bass can undoubtedly be saved by cutting out the neck-thru section, and you can start over with a fresh neck blank and the extra knowledge gained by experience.

Flawless repair work there - darned if I can tell where the piece is. Good job on the book press. I've always thought they'd make great body clamps, but the only ones I can find are always sold in secondhand shops for $400+. Seems there must be some kind of weird market for them down here that allows people to charge that kind of money for 'em.

Cheers. Really happy with the way this one has turned out so far. Best sounding, best intonating. The fan fretting is really comfortable and easy to adapt to, much more than I was expectiing.

Getting dangerously close to wrapping this one up. Just need to do a trussrod cover, finalise shaping the nut and let it bed down for a bit. 'Scuse the image quality - indoor lighting in the middle of winter aint that great for pictures: One thing I've noticed from the brief play I've had of the guitar in its current state is that these ABM saddles are going to need some notches filed into the tops. The breakpoints of each saddle is flat across the full width, and there's nothing to prevent the string from moving laterally. Any string bends on the upper registers tends to make the strings roll sideways across the saddle.

There are two ways to do a scarf - one has the extension joined under the fretboard at about the 2nd/3rd fret, the other has the extension joined through the headstock. http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fapi.ning.com%2Ffiles%2FKUh3i5J4pFthuEO7rQPcAk6SEXU-TKWdTjXUyS48JpjpQ6zRyizVvbVdZlMeKnVLRrV-hkiF6EDpKCElF6VaptdATFSHgg2c%2FNeckscarfcut.jpg%253Fwidth%253D750&imgrefurl=http%3A%2F%2Fwww.cigarboxnation.com%2Fforum%2Ftopics%2Fneck-scarf-joint-question%3Fid%3D2592684%253ATopic%253A1359079%26page%3D2&h=360&w=750&tbnid=RRJ2dFVdNTRSDM%3A&zoom=1&docid=y56qAzcory34mM&ei=L6vJU9_QC4_c8AWJgoLQDg&tbm=isch&client=firefox-a&ved=0CCgQMygLMAs&iact=rc&uact=3&dur=2274&page=1&start=0&ndsp=20 For maximum strength you want the first option, where the fretboard supports the join between the two pieces. Lots of examples of a simple scarf on a plain maple neck: http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fi1008.photobucket.com%2Falbums%2Faf201%2Fwurmluke%2FDSC02767.jpg&imgrefurl=http%3A%2F%2Fwww.jemsite.com%2Fforums%2Ff21%2Fneck-scarf-joint-97809.html&h=768&w=1024&tbnid=oCRvm5bpYm86OM%3A&zoom=1&docid=0o2WuJ_TATDb1M&ei=L6vJU9_QC4_c8AWJgoLQDg&tbm=isch&client=firefox-a&ved=0CC4QMygRMBE&iact=rc&uact=3&dur=830&page=1&start=0&ndsp=20 http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fsglguitars.s5.com%2FImages%2F051015StrattonJemPainted049.jpg&imgrefurl=http%3A%2F%2Fsglguitars.s5.com%2FCustom%2520Gallery.html&h=427&w=640&tbnid=-wSzVxsO8iSgeM%3A&zoom=1&docid=th9qN9_qdAd2xM&ei=mazJU5X3Lszh8AXPvIKYAQ&tbm=isch&client=firefox-a&ved=0CB8QMygEMAQ&iact=rc&uact=3&dur=1576&page=1&start=0&ndsp=22 http://www.google.com.au/imgres?imgurl=http%3A%2F%2Fwww.warmoth.com%2Fguitar%2Fimages%2Fnecks%2Fscarf_joint.jpg&imgrefurl=http%3A%2F%2Fwww.acousticguitarforum.com%2Fforums%2Fshowthread.php%3Ft%3D81858%26page%3D3&h=128&w=360&tbnid=G6jdEh9jg-hbMM%3A&zoom=1&docid=UmEDR9iaYU7p8M&ei=mazJU5X3Lszh8AXPvIKYAQ&tbm=isch&client=firefox-a&ved=0CEMQMyggMCA&iact=rc&uact=3&dur=796&page=2&start=22&ndsp=24 Every base model Ibanez RG or S I've ever owned had a maple neck done this way.

Madness!

+1 on the angled headstock with scarf joint. The old Gibson method of making an angled headstock from a one-piece neck blank requires a thicker blank to start with, wastes more timber (half the blank gets thrown away) and creates a headstock/neck transistion that can be prone to weakness. Scarfed neck joints have been used reliably for years by many manufacturers as a method of creating strong headstock/neck transitions and for their efficient use of timber. Don't be too concerned about the visible transition line - embrace it! Do what many builders here do and make it a feature by laminating some contrasting timber into the scarf.

Magnificent, Scott. Justin is one lucky chap to be getting such a beautiful instrument.

Some companies will supply viscosity reducers as an additive to their epoxy range that would aid levelling. Pretty sure West Systems has such an additive for their products. I've done the same thing Scott has suggested, but only as a grain filler which was then sanded back down level to the surface of the wood, so the final appearance of the dried epoxy wasn't an issue. Managing epoxy as a final coat to be completely level over non-flat surfaces (eg, backs of necks, carved-top bodies, cutaways etc) is going to be extremely challenging. All the examples I've seen of using epoxy as a final coat have always been flat surfaces - table tops, bar tops, decorative paperweights etc.

Might take a look at Fast Guitars kit section. If their LP kit is anything to go by (see RADs build thread ) it is probably the best you can get for the price.

Some of the clear casting epoxies I've seen down here suggest using a small blowtorch to heat the epoxy to help level and prevent bubbles forming as it dries. Never tried it myself (sounds risky anyway).

Contour gauge is a good non-intrusive idea, although it might be more difficult to get accurate results on areas where the profile changes rapidly over a short distance (neck to heel transition for example).

Re, modelling the complex shapes: Have you considered physically making some of the difficult parts (eg, headstock-to-neck transition) using pine, MDF or other cheap materials by hand, slicing them up into 5-10mm cross sections, laying them on a scanner one by one and joining all the cross-sectional 2D scans into a 3D profile? I'm thinking kinda like putting the skin on a boat hull.

No hard and fast rule. As thick as you want as long as you leave sufficient clearance inside for the electrickery bits, and the screws you have to hold the cover are long enough.

This'll do the trick.