Finished! A Bridge Too Far?

[Andyjr1515]

Yes - it's an old picture....

[Owen]

[quote name='Andyjr1515' timestamp='1494971602' post='3300161']
The cross section here will be something like this (this is full size):


The minimum radius at the edges will be 12-15mm at these two extremes and larger where the body is narrower
[/quote]

Mmmmmmmmmmmm, curvy goodness!

[Andyjr1515]

The carve is a softly-softly job.

I started by using a generous round over router bit on the back to give myself a datum to carve towards:



At the moment I'm just using a couple of hand planes. With a super-sharp blade, I'm taking off a thickness per stroke thin enough to read news-print through. This is a slow, careful job.

Next job was to mark the fretboard-mating edge with soft pencil so that it doesn't get inadvertently planed and end up no longer flush...:


The freshly planed surface shows the figuring very well:


Here, the larger bout of the lower body half is starting to get there and the upper half is about halfway:


In the meantime, I've been speaking to Martin at Herricks to firm up the custom coils he's doing for us. This is where the positions will be underneath the fretboard. The cable channel, already cut, is in the centre of the lower body half join:



OK - that's the cup of tea done. Now it's time to hone the plane blades and continue carving

Edited May 17, 2017 by Andyjr1515

[Bigwan]

Looking awesome!

[Andyjr1515]

[quote name='Bigwan' timestamp='1495032489' post='3300704']
Looking awesome!
[/quote]
Thanks!


Probably done enough for one day. Best to leave it and review it in the morning. This isn't the final roundover (and isn't all the way round anyway) but it gives me a lot more idea how close the carve is getting:


It's pretty much there in terms of planing - before I then go onto sanding - for the lower large bout, but this view shows that I still have a 'hump' on the upper large bout relative to the fretboard:



I'm pleased with today's progress

[cheddatom]

I'm really enjoying this thread

[TheGreek]

"[color=#282828][font=helvetica, arial, sans-serif]I'm pleased with today's progress [/font][/color] [color=#282828][font=helvetica, arial, sans-serif] "[/font][/color]

[color=#282828][font=helvetica, arial, sans-serif]Me too....sit down, put your feet up, have a cup of tea and a biscuit.[/font][/color]

Edited May 17, 2017 by TheGreek

[Andyjr1515]

[quote name='TheGreek' timestamp='1495036584' post='3300755']
"[color=#282828][font=helvetica, arial, sans-serif]I'm pleased with today's progress [/font][/color] [color=#282828][font=helvetica, arial, sans-serif] "[/font][/color]

[color=#282828][font=helvetica, arial, sans-serif]Me too....sit down, put your feet up, have a cup of tea and a biscuit.[/font][/color]
[/quote]
Actually, I might just do that!

[LukeFRC]

It's like if Ned steinberger took acid

[Andyjr1515]

[quote name='LukeFRC' timestamp='1495043217' post='3300837']
It's like if Ned steinberger took acid
[/quote]
Ooooh - that sounds even better than tea and biscuits!

[Norris]

[quote name='Andyjr1515' timestamp='1494950117' post='3299896']
I can't believe that MrsNorris would do such a thing. And anyway, Norris tells me she's much too preoccupied trying to work out where on earth her clothes rack went to worry about trivia like that
[/quote]

I had to buy her a new one for domestic duties

[Andyjr1515]

[quote name='Norris' timestamp='1495047043' post='3300888']
I had to buy her a new one for domestic duties
[/quote]

[Andyjr1515]

Now I know broadly where the body surface is going to be, the next task is sorting the control chamber.

This is the basic idea:


Basically the controls will be accessible from the back but hidden from the front - a bit like Gelfin's Smoothhound on his Mouradian style:




From the back it will look something like (without the sharp wing-tip):



Basically it will have, as a minimum:[list]
[*]Onboard mixing pre-amp
[*]9v battery (18 v if it will fit)
[*]Piezo / Magnetic blend control
[*]Master Volume
[*]Jack
[/list]
I think somewhere I've seen a mini stacked pot. If I'm right I may even be able to incorporate a master tone...time will tell on that one. If not, I'll probably pop a piezo tone trim pot under the cover just in case it's a bit too jangly


After talking to Jez at the Basschat Bash, I've opted for the John East MPM01 preamp which should be with me early next week. I looked at a number of mixing preamp, including Fishman, L R Baggs
Bartolini, Cafe Walter and John East.

The John East has the advantage of having trims on both the piezo and the magnetic pickups so it should be possible to dial in the right balance for starters and then have the full live playing spectrum on the blend knob.

I will hog out the chambers with a forstner but will probably use chisels to do the final shaping - I've got to get pretty close to breakthrough and simply too much can go wrong with routers....

I'll let you know how I get on

[samhay]

With the MPM01, you shouldn't need a dual-gang pot for the mix/blend control.

[Andyjr1515]

[quote name='samhay' timestamp='1495106871' post='3301295']
With the MPM01, you shouldn't need a dual-gang pot for the mix/blend control.
[/quote]
Oh...that's interesting, samhay.

How do you get the blend? I assumed you would blend between the piezo pre output and the mixer output. Is it just a single pot off the mixer output? The PDF on the web site isn't overly clear....

[Owen]

Dual-gang blah blah blah. I have no idea what you are talking about, but I DO have an MPM01 in a bass and it has a pan pot in it to choose Mag/Piezo or blend.

[Jabba_the_gut]

Andy, I got a couple of drawings from John East - will send you a copy when I get home.

Cheers

[Andyjr1515]

While I work out exactly what type of pots I will be using with the pre-amp mixer, the fact remains that there will be only room for two of them

The access chamber has now been forstner-drilled and chiselled out.

Here you see it:


...and here you don't:

[Andyjr1515]

[quote name='Jabba_the_gut' timestamp='1495113198' post='3301367']
Andy, I got a couple of drawings from John East - will send you a copy when I get home.

Cheers
[/quote]
Great - thanks, Jez

[Andyjr1515]

This afternoon is the carve of the main controls chamber. For those of you who are paying attention ( ), you will remember that the back is also going to be scooped out. So the control chamber cover will also need carving...

[bartelby]

[quote name='Andyjr1515' timestamp='1495114230' post='3301380']
So the control chamber cover will also need carving...
[/quote]

Nice to see you're making things easy for yourself...

[Andyjr1515]

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

[Andyjr1515]

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

[Jabba_the_gut]

E-mailed you the drawings Andy. Cheers

[Andyjr1515]

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

Andy