Build Diary of an MMB-5

**RalphH** · 07-08-2017, 07:19 AM

Day three: finishing the woodwork.

On the task list today is:
• Routing the hole for the battery compartment
• Drilling the hole for the output jack
• Modifying the PUP compartment so the PUP can be mounted in the optimum position for the MM tone. (And match the position dictated by the replacement Stingray 5 scratch plate)
As the battery compartment was a deep rout (over 25mm) and needed to be tackled in 5mm increments so not to overload the battery router, I made a little jig that was clamped to the body.
Next was drilling the hole for the output jack; this was being moved to the edge of the body as the position on the control plate where it would normally be will be occupied by the treble control of the two band EQ.
I bored a shallow 22mm diam hole (spade bit) first to allow for the convex shape of the mounting plate. Next was the 14mm hole for the body of the switched socket.

Existing PUP cavity was way too large for what was required from the factory, but still needed to be moved 12 mm toward the bridge to position so the pole pieces of the PUP are the correct distance from the saddles.(MM spec)
The combination of the pickup location shift and the routing of the battery compartment necessitated the re-routing of the PUP wire toward the location of the volume pots.

With all the woodwork complete, it’s now on to the control plate and electronics. It's starting to look like an SR5 replica now...

**andrewdosborne** · 07-08-2017, 07:48 AM

Great work coming along nicely

**wazkelly** · 07-08-2017, 07:04 PM

Much better job on the battery box than what I did on mine.

**RalphH** · 08-08-2017, 05:00 AM

Originally Posted by wazkelly

Much better job on the battery box than what I did on mine.

Yours is still functional, took a bit longer that's all..

Have you done your wiring yet Waz? If not, hold off for a few days and I'll share my setup with the preamp etc mounted on the control plate as a tidy, drop-in solution. May be a solution for you too...

**wazkelly** · 08-08-2017, 08:04 PM

Originally Posted by RalphH

Yours is still functional, took a bit longer that's all..

Have you done your wiring yet Waz? If not, hold off for a few days and I'll share my setup with the preamp etc mounted on the control plate as a tidy, drop-in solution. May be a solution for you too...

Hi Ralph, I am only 6 or 7 coats into the Tru Oil top coats with another 12 - 15 to do so that it builds up enough depth for intermittent wet sanding and ultimate final polish. When that has all been done I usually wire things up and then string it all together. With fairly cool weather here at present best to leave things a bit longer to fully cure and reckon that might be 4 - 6 weeks away. Probably not as cold here as over the ditch just north of Auckland?

**RalphH** · 09-08-2017, 09:11 AM

Originally Posted by wazkelly

Hi Ralph, I am only 6 or 7 coats into the Tru Oil top coats with another 12 - 15 to do so that it builds up enough depth for intermittent wet sanding and ultimate final polish. When that has all been done I usually wire things up and then string it all together. With fairly cool weather here at present best to leave things a bit longer to fully cure and reckon that might be 4 - 6 weeks away. Probably not as cold here as over the ditch just north of Auckland?

Yep, been quite wet and consequently humid here for the drying of finishes in a reasonable time. If this keeps up when I get round to painting, I may try the idea shown here where a cheapie portable greenhouse has been re-purposed as a drying booth. Just stick a 20W wardrobe heater or some Damp-Rid it the bottom and that will speed up your curing times...

**RalphH** · 14-08-2017, 09:26 AM

Fitting the preamp in to the control cavity was always going to be tricky, so I decided to take the MM approach and mount everything on the back of the control plate and use high grade connectors to plug everything together. This necessitated a little notching of the original control cavity to fit the preamp block, and cable holes opened up to suit the connector sizes.

Photo of the control plate shows wiring configuration for individual volume controls for each PUP coil in parallel, however I intend to experiment with a push/pull parallel series switched pot later.
This is another benefit of the removable “plug n play” control plate; modifications are really easy.

With all this working, it was time to finish the last of the installation of parts, assemble everything for the final fit and test before commencing the sanding and finishing process.
First was the drilling of the bridge plate to accommodate the thru body stringing. The 4.5mm holes were transferred through the body on the drill press and then the 9.5mm holes for the ferrules were drilled in from the back. I will use a press to push these in after the painting is complete.

As previously discovered, never assume parts (In this case the heel of the neck) are machined correctly from the factory- the image below shows the convex surface that had to be straightened to obtain a good fit. This remedial work now has the neck sitting almost 2mm lower in the neck pocket than I wanted; meaning the bridge saddles are almost all the way to the bottom of their adjustment on the B and G strings.
When I re-assemble the bass after painting, I’ll correct this with a full pocket shim.

And so here it is, fully assembled and functional- minus paint, full set-up and intonation. I have a set of Schaller BM 4L +1R machine heads on the way, and thankfully the mounting holes are the same as the ones that came with the kit. Unfortunately, I had to spend my upgrade money in Germany- the Australian/New Zealand guitar parts suppliers don’t appear to serve the 5 string market as well as they could.

Next up: body prep and paint.