Andyjr1515

Mick and I are getting close to finalising the headstock shape and in the meantime I've been starting to round the edges: Mick has asked that there are no flat surfaces anywhere so the headstock will also be radiused and rounded. In the meantime I've just head that the custom pickup coils are ready

[quote name='ikay' timestamp='1495473065' post='3304005'] Re #4 - only thing I'd add to this is that the slightly greater string length from the saddle to the tailpiece, and the shallower break angle over the saddles, makes the strings feel a bit more 'compliant' compared with a regular one-piece bridge. Both these factors give the illusion of slightly less tension but in fact it's just down to the geometry and the strings moving ever so slightly more freely over the saddles. The string tension itself is exactly the same as if they were on any other bass of the same scale. [/quote] ^ Yup - spot on

With reference to intonation, Jack is also right where you have a floating bridge! If a bridge is set at EXACTLY the scale length, then what you will generally find is that the notes ring out sharper and sharper as you go up the fretboard. That is because, by pressing the string down to the fret, you are basically doing a string-bend, albeit vertically and not horizontally. The further up the frets you go, the larger the gap is between the string and the frets and therefore the more you are bending the string. Also the thicker the string, the more the bending affects the pitch. So the saddles are actually usually positioned approximately 1 to 3mm further back than the actual scale length To set your bridge in a rough approximation of intonated, position either the bridge or saddles so that G is 1mm longer than the 30.5" scale length and the E is 3mm longer and the other two are relative to those two points. Then tune up to proper pitch, sound the harmonic at the 12th fret and then CAREFULLY fret down (vertical so you are not actually bending the strings horizontally too). If it's the same note, you are intonated. If the fretted note is sharp, move the bridge (if it's all of them) or the saddle (if it's only one or two of them) back a mm and try again. Likewise, if the fretted note is flat, then move the bridge / saddle forward a mm and try again.

I agree with Jack's answers above. I think your confusion is probably between string length and scale length - easily done. The scale length - 30" on your Mustang and 30.5" on your violin bass - is the distance from the nut to the bridge saddles, and nothing to do with how much string is behind the saddle. The string tension, for a given set of strings, will be the same as any other 30.5" scale bass, although a tiny bit higher than any 30" scale bass. Different designs of basses then have different ways of securing the strings - some attached to the bridge assembly itself (such as a Fender P-bass) where the ball ends are very close to the saddles and some with a string retaining stop bar some distance behind (think Warwick or a semi-acoustic jazz design). Neither affects the scale length or string tension. Hope that helps

For me, it's Tru Oil slurry and buffed everytime. Basically you apply a couple of coats, allowed to soak in and dry. Then apply the oil with fine grade wet n dry (400 or 800 grit), using the oil as the wet. This creates a wood / oil slurry that fills the pores and grain. Within a few minutes, wipe it all off, back down to the wood and let it dry. Repeat this step and let it dry overnight. Repeat the step, but now not only wipe the slurry off, but vigorously buff it up to a dry shine. Let it fully dry and then one more buff for good measure. If you've missed a bit that isn't silky smooth to the touch, just repeat the final step. As Grangur says, let the rags dry laid out to avoid risk of spontaneous combustion and also best to wear latex or nitrile gloves - it's a messy job and some people are sensitive to the oil. The result will be a super-silky smooth neck that still feels like wood. Wonderful!

[quote name='owen' timestamp='1495460356' post='3303882'] You know, fancy dan wood tops are all well and good, but when you can follow the grain all the way round an instrument - that is where it is at! [/quote]

The basic body carve pretty much done - just need to check with Mick how rounded he wants the lower horn. Lots of sanding to do but here's how it's looking: I talked about there being a drop-away after the 24th fret to at least provide a modicum of playing clearance from the bass's top. This is what I meant: I've also deepened the control chamber and now know I can get a battery in and a cover on! So that and the pickup cover are shortly due on the list. I can't carve the neck until the fretboard's on and I can't glue the fretboard on until I have the coils, that are being made at this very moment, so the covers are probably next on the 'to-do' list Oh - and Mick and I are crystallising the design thoughts of the headstock...

[quote name='JPJ' timestamp='1495360004' post='3303173'] I've got to admit that I didn't like the original concept. I'm a 'dyed in the wool' Fender shaped bass type of guy, who prefers big slabs of wood. But this is shaping up (no pun intended) to be something really special. I love how the flame in the body wing wood has 'popped' as you've carved away the excess material, and the whole thing is a testament to your woodworking skills. One question though, how is the overall weight now you've done most of the wood removal and how is the balance? [/quote] Thanks, JPJ I must add the hardware so I've got for a better estimate, but at the moment it's sitting at around 5lb 4oz for all the wooden bits. That will reduce a tad with the carving of the neck then plus the tuner block and pickups, etc. Balance wise, it's OK at the moment and the headstock equipment will be very light indeed so I suspect it will be fine. Difficult to know exactly where it will hang in terms of arm reach but, again, I have high hopes that it will be good

The carve continues. I don't know if everyone else is the same but, after sorting a basic concept out and the absolute functional positions, I carve on the basis of removing what doesn't seem to belong and what creates the illusion I am attempting. It's a slow process and this is probably half way through time-wise... so another couple of days for the basic carve. What I am trying to do is to create the illusion of the 'contact lens' without compromising the functional needs of the controls, neck and pickup provisions. Here is is so far end on: Mick doesn't want the edges to be sharp so the tip won't be much narrower than this, However, on the left hand side I will increase the under-scoop and bring the top radius just a touch closer to the fretboard. The right hand side is scooped more once you get past the chamber, but I'm leaving the back flat until I've safely got all the electronics and cover confirmed to fit OK. So there is a bit of artistic licence going on. Nevertheless, even though it will be even closer when finished, the radius does actually visually look compatible on the top: ... and it already is starting to look sleek and contact lensy: Also, the neck carve will transform the look. Maybe it's familiarity with the shape on my part and me now starting to see in wood what I've broadly had sitting in my head for the past few months - but don't you agree that there is an undeniable elegance creeping in here?

Thanks, folks. It means a great deal

That's really good news, Nic . Thanks for posting. Andy

Beautiful....

Softly, softly, catchee monkey,

OK - couldn't wait until tomorrow Back carve has started:

Final couple of jobs ready for starting the carve on the back over the weekend, MrsAndyjr1515 permitting. I've glued a couple of sycamore fillets either side of the tuner block wedge and routed the back of the neck ready for the coils access cover: The stripy cover will be flush with the stripy neck, and the body rebates will be carved down to the neck level as part of creating the concave curve at the back.

One of the jobs to be done while the back is still flat is the holes for the magnetic pickup coils: The other is the rout to flush fit the hatch at the back that will cover those holes - which will be a longer version of this...

[quote name='TheGreek' timestamp='1495191845' post='3301992'] It's all Greek to me!! [/quote]

[quote name='samhay' timestamp='1495185667' post='3301909'] ^That all makes sense. Why that's not on the website escapes me. John's potentiometer suggestions of 5k blend, 25k volume seem quite sensible, so that's what I would use. You may find it easier to get hold of 4.7k and 22k pots. These will work fine too. [/quote] Great - thanks

[quote name='Jabba_the_gut' timestamp='1495179414' post='3301823'] E-mailed you the drawings Andy. Cheers [/quote] Brilliant! In addition to a couple of more technical drawings explaining the shunt options, this is the one that, for me, clarifies the basic wiring options and is pretty much what samhay says above: Now I don't reckon many of us would have been able to work that out without the diagram! Many thanks samhay and Jabba_the_gut Andy

[quote name='samhay' timestamp='1495183857' post='3301884'] Indeed, the MPM01 'detailed' information sheet is pretty poor. I would expect input and output impedance and some suggested wiring schemes at a minimum. (John - if you are listening...). Sound like you may have this covered now though. The MPM01 page confirms that 'Outputs can be mixed with the addition of a simple single gang blend pot.' I assume that both the mixer and piezo outputs are low-impedance. The pictures of the unit show an 8 pin IC, which I assume is a dual op-amp, which would almost certainly be configured this way. I would try a small-ish value pot - maybe try 10k - wired with lug 1 to the mixer output, lug 3 to the piezo output (or vice versa) and lug 2 connect to lug 3 of the volume pot. I would then use a 100k pot for the volume. You could scale these values up, but the key is to keep the mix pot much smaller resistance that the volume pot. The problem you will have is that the tone control won't work very well if wired as for a passive bass - i.e from lug 3 (or 2) of volume pot. However, if you don't have room for a tone control anyway, then that problem is solved. [/quote] That's great info, samhay. I've just read Jez's mail which pretty much confirms what you say - I'll post the pics that John East did for Jez...and drop John a mail suggesting he just adds this to his website to replace the out of date one that's there at the moment! Thanks Andy

[quote name='Si600' timestamp='1495183187' post='3301870'] Why haven't you finished carving the front before starting the control cavity? [/quote] It's a bit iterative. It's only the lower bout that's critical but where I've got to so far on that is the minimum curve I would be happy with: I then need to work out how deep my chamber can go without breaking through the top, and how deep it needs to go to accommodate the components, the cover and the scoop at the back. If it's generous, then I will go back to the top and increase the curve a tad. If it's tight, it will stay where it is. Also, what I do with the rest of the top carve will depend on what I've done to the back carve. So the sequence will be: [list] [*]Sort the back carve [*]Review the top carve of the lower bout [*]Finish the top carve [/list] ...if that make any sense whatsoever! Once I have the final top curve sorted of this boutcurve

Well, this looks almost artistic... ...which is probably more than the carve itself is The carved chamber's essential kit:[list=1] [*]Thickness gauge [*]Chisel [*]Deepest item you're going to need to fit under a flush cover [/list] I'm at another "Sit and THINK, Andyjr1515, before even touching anything that is going to remove wood". It is a great temptation to get out the pullshave and start the back curved carve - but I mustn't...yet Factors include:[list] [*]I need to preserve the present flat surfaces until I'm sure all and any routing has been completed. It is extremely difficult to rout on a scooped surface - ask me how I know! The one thing that probably will be routed is the covered shallow chamber the pickup coils will sit under [*]I probably should finish the reference point roundover along the back edge [*]I need to add the two small sycamore fillets at either side of the tuner block support [*]I need to work out just how much depth will be lost from the control chamber when I scoop - and where. Almost certainly I will need to go deeper (and therefore thinner) with the control chamber carve if I want to have a flush cover [/list] So I'm going to spend much of the day just sitting on my hands, looking at it

[quote name='Jabba_the_gut' timestamp='1495179414' post='3301823'] E-mailed you the drawings Andy. Cheers [/quote] Great - thanks, Jez Andy

Of all the 'go carefully' jobs, this is the one... It needs to be deep enough, but the remaining top needs to be thick enough. I know carved-archtop makers do this all the time but I'm going very carefully. I will check the thickness with some calipers this evening but I reckon there's another 3mm to come out of this. A job for tomorrow.... You can see here in the top left of the chamber the pickup cable rail breaking through. Phew - right place

[quote name='bartelby' timestamp='1495115901' post='3301404'] Nice to see you're making things easy for yourself... [/quote]