Preamp Pedal

Piezo pickups are a great and inexpensive way to “electrify” an instrument, but they don’t have a lot of output.  A preamp is normally used to boost the signal to a more usable level.

Instead of installing a preamp on every instrument that I make, I decided to make a pedal.

I used a piezo preamp system that would normally be installed on an acoustic guitar.  I also used a heavy duty triple pole double throw(3PDT) stomp switch, an LED, a resistor, a metal enclosure, and an extra mono jack.

The piezo preamp is an inexpensive model that I bought online.

I cut out a hole for the preamp and drilled holes for the jacks and switch.  The preamp is now smaller because I trimmed off the 9V battery compartment.

This mess is my prototype to make sure that everything is working properly.

By stepping on the switch, you toggle between the two settings which are as follows:

[Setting 1] LED off. Preamp off.  Bypass preamp.

[Setting 2] LED on. Preamp on. Through preamp.

I painted the enclosure with some leftover paint from this project.

I assembled and bench tested it.

It is now the first pedal in my pedal chain.

I wired it so that it would run off of the same 9V daisy chain that my other pedals use.  (I try to avoid using batteries whenever I can.)

The preamp pedal is now a worthy, albeit somewhat bulky, addition to my pedal board.

Bass Ukulele Build : part 02 – Body and Neck

The body is made of ash.  The neck was made with three pieces of maple.  The headstock was scarf jointed to the neck and the fretboard was glued to the top.  I got the specialized tuners and nut from https://www.largesound.com/buy/.  They provide replacement parts for Ashbory Basses.   The bridge is a knockoff “Hipshot A Style” bridge.  This type of bridge allows for the mounting of the thick “Road Toad” strings.

I sealed and primed the body. I drilled a larger hole by the the bridge to allow a rod piezo pickup to be mounted by the back of the bridge.

With a drill and a chisel, I hollowed out a cavity for a 9V battery holder.  This bass ukulele will have an active pre-amp to boost the low output of the piezo rod.

The neck was given a nitrocellulose lacquer finish after side markers were installed.

Next, the body will be given a beautiful orange finish.  Once the color and clear coats have cured, it’ll get a good buffing and polish.  Finally, my favorite steps will arrive.  That is assembling and playing the instrument.  There is something almost magical about the first tune on a brand new instrument.

 

Telecaster uke build : part 08 – Complete!

After waiting for the clear coat to cure, the time came to wet sand, apply the polishing compound, and polish the body.  I used 1000 grit sandpaper to wet sand the body.  I then used a rag to apply “fine” and then “swirl remover” polishing compound to the finish. “Meguiar’s Mirror Glaze #7″ is what I used to give the body a final polish.  It’s a car glaze, but I’ve seen it mentioned on a lot of guitar forums as a guitar polish.  It’s worked well so far.

I used this wiring diagram as a base:  One pickup, one volume, one tone.

I tweaked a few things to adjust for the higher frequencies of a electric ukulele.  250K ohm potentiometers were used instead of the 500K ones.  A 0.020 microfarad capacitor was used instead of the .047 microfarad one.  In addition, a 0.001 microfarad capactor was added between the center and right lugs.  (Okay, so I “tweaked” everything.)

Now, the Telecaster Ukulele is ready to assemble and then play!   In this video, I give a demonstration of the uke in action, and show it being assembled in real time (I work fast).

It’s been fun making this ukulele and sharing the details.  It was a lot of work, but now I have a custom instrument that plays beautifully and looks great.

Ammo Box Ukulele

Sometimes the desire to ROCK is tempered by a lack of tools.  To make a regular solid body electric ukulele, you need a scroll saw (or a band saw) and a router along with some other basic tools.  However, a hollow enclosure can be used for the body, which eliminates the need to cut and rout a wooden body.

For my ukulele, I used an ammo box that I purchased at an army surplus store.  This same kind of thing could be done with any type of sturdy wood, metal, or plastic box.

The neck was made with two pieces of mahogany scarf jointed together. Less expensive and more readily available wood could also be used.  In fact, other types of wood would probably be more congruent with the “DIY spirit”.

In keeping with the ammunition theme, many of the hardware appointments were made with spent bullet shells.  One the most difficult parts of this build was cutting a hole in the thick metal box for the single coil pickup.  I used a hacksaw blade and a file to do this.  A jig saw would have been much easier.

The bridge was made with a 30.06 shell.  A shotgun shell top serves as the volume knob.

The wiring schematic is pretty basic:  One pickup, One volume schematic

Spent .22 shells serve as fret markers.

Here is a demo of it in action!

https://www.youtube.com/watch?v=sJwUR12x1Ig

Bass Ukulele Build : part 01 – Planning

I want a bass ukulele.  After building a few dozen instruments, the thought of simply buying one from store seems very boring.  I will therefore expend the time and money to make a custom bass ukulele that will fulfill my desire.

Before I build, I make a paper mock-up of the instrument. (I included a concert sized acoustic ukulele for scale)

Here are the elements that I want to have:

  • 20 inch scale length
  • Black Road Toad polyurethane strings
  • Maple neck/headstock/fretboard
  • Under bridge piezo pickup
  • On board Preamp
  • Black Hardware
  • Orange Paint for the body

The combination of orange, black, and maple should make for an interesting looking instrument.  I hope that I don’t live to regret making a bright orange ukulele.  Hopefully, a funky color will look good on a funky ukulele.

Telecaster uke build : part 07 – Primer, paint, and clear coat

I applied a nitrocellulose primer to the sealed wood body. 2-3 coats were needed. Any slight bumps were sanded flat with 1000 grit sandpaper.

The “Midnight Wine” color coat went over the primer.  This color started to worry me.  I said to myself, “I don’t want a plum colored electric ukulele”.   I pressed on, knowing that if I hated the color, I could always repaint. I did about two coats, then noticed that my overzealous painting had cause a couple of sags on the back.  After letting it dry for a day, I used some 320 grit and then some 1000 grit sandpaper to reflatten the surface.  I sanded just enough to correct the sags, but not enough to sand through all of the color coats.  Once I was pleased with the surface, I did two more color coats.

Next came about 6 or 7 clear coats.  Clear gloss nitrocellulose lacquer was used. After the clear coats were applied, I noticed that the color had changed slightly.  It had become much closer to the dark, rich “Midnight Wine” color that I was expecting.  This pleased me exceedingly.

Filling the grain, sealing the wood, applying the color coats, and then putting on the clear coats, makes for a nice finish.  Even if you are using spray cans (like I do), you can get great results.  I follow the Stewart-MacDonald Nitrocellulose Finishing Schedule.

The next step is the most agonizing for me.  Waiting.  It is recommended that you allow 10-14 days for the finish to cure before wet sanding and buffing the finish.  I’m planning on waiting two full weeks before touching the body again.  It will be hard, but I will be strong.  Hopefully my patience will yield a beautiful, glossy finish.

Telecaster uke build : part 06 – Bridge and first assembly

My four string bridge arrived in the mail, so I was able to drill the holes for the screws and strings.  The holes for the strings go all the way through the body.

I used a long drill bit to drill a hole from the bridge to the control cavity.  I will run a wire through this hole to ground the bridge.

A long drill bit is nice to have.  It’s difficult to use a regular length bit and still get the desired angle without rubbing the wood with the drill.

On the back side of the body, I countersunk holes for the string ferrules.

The cutting, shaping, and drilling are now complete.  Before painting, I like to assemble the major components on the instrument.  This gives me confidence that all of the parts will fit together.  If something needs to be adjusted, it’s much easier and cleaner to do it now.

Now that the body has been sealed, it is ready to be primed, painted, and clear coated.  Midnight Wine paint will look great on this.  (I’ve already given the maple neck a clear nitrocellulose finish, so it’s ready to go)

Telecaster uke build : part 05 – The neck (frets and such)

I used my recently acquired drill press to drill holes for the fret and side markers.  The side markers were made by drilling shallow holes, pushing thin plastic rods into the holes and then flush cutting the rods.  The fret markers were made by gluing the premade hard plastic dots into the holes.

The frets were pounded into the slots with a plastic tipped hammer.  Excess fretwire was trimmed off with a fret cutter.

I use t-nuts to attach the neck to the body.  I feel that this makes the connection stronger.  The neck will have a lot of tension on it, so I want it to be securely fastened.  Small screws help to hold the t-nuts in place.

I took a chisel and cut out the area for the t-nuts.  This will make the top of the t-nuts and screws flush with the bottom of the neck.

I will use an oval jack plate for the neck plate.

The neck is ready to be clear coated.  I think I’ll do about 6-7 coats of clear laquer.

Telecaster uke build : part 04 – Routing the body

The major shaping and routing were done with a round-over bit and a straight bit.   I used the round-over bit around the edge.  The straight bit was used for the pickup and control cavities, along with the neck pocket.

The body is now routed.  The routing for the control cavity isn’t my best work, but the control plate will easily cover everything.

Timbermate wood filler is great stuff.  Even though alder is considered a non-porous wood,  I’ve found that spreading wood filler all over the wood (I rub it on with a gloved hand) makes sanding the wood smooth much easier.

Since I’m painting this body, I didn’t worry that my wood filler stained the wood a little.  If you wanted a natural finish on your instrument, you would use a wood filler with a hue closer to the wood’s natural color.

I penciled in the pickguard on the body.  (Remember that if you are painting the body, then you can mark out the various parts with impunity.  If you are running out of paper, you could even use it to do long division.  If your finish will be transparent, mark in a way that can easily be erased.) I then traced the pickguard shape on some tracing paper.  This is a great way to get a template for the scroll saw cutting.

The pickguard is now ready for holes.  I think I’ll use 8 screws to attach it to the body.

The body is ready to be to be sealed.  Applying a clear coat and then sanding it as smooth as possible is critical in order to have a nice, flat surface for the paint.

The bridge hasn’t arrived yet.  Normally, I’d drill all of the holes before I sealed the body, but that’s not critical.  I’ll just give the laquer time to cure, and then finish drilling.