Sunday, January 26, 2014

12V wall wart power supply in a jar


I did this project a while back and didn't document it terribly well, so I'll keep it short. About a year ago, I took apart a 5V / 12V SMPS wall-wart (for a long-obsolete Iomega Jaz drive, 5V 1A and 12V 0.75A, IIRC) out of curiosity and destroyed its casing by doing so. Soon after I found myself in need of a 12V source of power, and running a wall wart without a case is a great way to kill yourself, so I needed to find an enclosure for it. So why not put it in a jar?

I punched some holes in the jar's lid to add a 3-prong IEC jack, a power switch, a standard 5.5mm DC barrel jack for the 12V (which plugs into the power supply via a 3.5mm jack), and a USB charging port (for the 5V), all held in with hot glue. The PCB is wired to those connectors and hangs off those wires like in the picture.

I also added LEDs because cool beans. Presently it powers my crufted set of computer speakers, and I occasionally charge my phone off the USB port.


Wednesday, January 1, 2014

Defretting a Squier bass guitar

I picked up bass guitar in high school, mostly as a result of listening to excessive amounts of Jaco Pastorius.

After using my high school's bass for over a year, graduation forced me to buy my own instrument. I originally intended to buy a fretless as my first bass. Unfortunately, that plan fell through - I specifically wanted a fretless Fender Jazz bass, but used Made-in-Mexico Fender Jazz fretless basses were priced above my reach, and I didn't dig the look of the budget Squier VM fretless. I wound up with a white, fretted Squier Classic Vibes Jazz Bass that I quite liked, which I promptly installed flatwounds and a black pickguard on and played on happily for several weeks. Still, the temptation to defret (especially after repeat listens to the bass intro from Weather Report's "Cannonball") was just too great.

So why fretless? 

-Much more control over pitch. Without frets, you're free to play much more expressively.  Smooth glissandos, cello-style vibrato, non-12 tone scales, and much more are possible with a fretless that are impossible with a standard fretted bass.
-Listen to some Jaco Pastorius - "Cannonball" (from Weather Report's album "Black Market" and "Continuum" (from Jaco's debut album) are pretty good examples of the expressiveness possible on a fretless.
-Fretless looks awesome. There's no frets breaking up the clean, sleek lines of the bass neck. 

Unfortunately:
-Fretless is (much) harder to play in tune for obvious reasons.
-A finger has much more area than a little wire fret, so fretless also changes the tone (which can be good or bad). 
-For the same reason, fretless basses often have less sustain. 
-It's hard/impossible to slap on a fretless.
-Unless you epoxy/hard-coat the fingerboard, roundwound strings can't be used without wearing out the fingerboard.
-Because they're more of a niche instrument, resale values (especially self-defretted ones) tend to be poor.

In my case, I was willing to tolerate a change in tone, didn't slap, used flatwounds anyways, and didn't intend to sell this bass ever. So defret it was.

Anyways, photos! Credits to Noel Hwang for many of them.
(The Jamaican strap, which I originally did not realize was of the Jamaican flag, was found in a thrift store for $3)



My bass, pre-defret
Removing the strings.
Masking tape so I don't damage the surrounding wood.

The frets were glued in, so I heated them up with a soldering iron to weaken the glue before removing the whole fret with a chisel. Masking tape was used to reduce fingerboard damage, but I often ended up burning the tape with the soldering iron, and the fingerboard often got chipped anyways. The chipping was minor though, and didn't end up affecting playability at all.
Using a soldering iron to weaken the glue.


Coming out (with taped scorched from soldering iron)


One out, nineteen to go. A lot of that crud is masking tape glue residue,
which was easily removed later with a sanding block.

The general strategy was to use chisel (with the soldering iron applying heat) to get under the fret at one side and push it out of the wood and up, and then slowly using the chisel (or pliers) to gently remove the rest of the fret, going from one side of the fret to the other. 



A fret. (the nail clippers in the background proved to be useless)

I slowly spent the next hour or so pulling all the frets out. It went pretty well - there some light chipping of the wood around the frets as I pulled them out, but nothing too heavy. The frets got a bit harder to pull as I went down the neck, most because it was harder to find a place to use as a fulcrum for the chisel.The last 3 frets or so took forever.

I also went too long with the soldering iron for the 2nd fret and ended up burning some of the wood, forming a cavity after the rosewood smoke cleared:




There was also some darkening around the wood on the other frets. I ended up filling the cavity with CA (super glue) and sanding it. It's visually still a bit noticeable, but it's perfectly flush with the wood.

No frets!
  I decided to fill the fret slots with black .020" styrene sheets, often available at hobbyshops; I bought mine's off Ebay at $7 for two 12"x12" sheets. I ended up using far less than that. The strings of a bass are at pretty high tension and pulls on the neck quite hard, so it's definitely advisable to fill them in. Black styrene looked decent against the rosewood, although they later proved a bit hard to see. 

I cut them into small strips the width of the fret slot with a pair of scissors. The bottom of the slots also have a slight radius, so it's a bit wise to cut a slight C-shape into the bottom of the styrene.



After being cut to width, CA was applied to both faces of the strip of styrene and the strip was inserted into the fret slot. It sticks pretty much upon contact, so you need to align it just right when you insert it.


Afterwards I shaved the plastic strips down as best I could with an X-acto knife. It doesn't have to be perfect, since the whole fingerboard is getting sanded later.



There were a few chips from earlier that I filled in with blobs of CA. They take a while to dry. The blobs were made flush in the sanding process later.

Noel was bored and decided to make me a 9.5" radius sanding block as a break from his electric scooter project  (Thanks Noel!). I put on a breathing mask (rosewood dust is quite an irritant) and sanded down the fingerboard until all the styrene strips and CA filler was completely flush and smooth.

I put the strings back on, picked it up, and plugged it in. What does it feel like? A bass with no frets. It takes a while to get used to, but eventually I got the hang of it. Playing it in tune is still tricky, but the gains in expressiveness is well worth it.
My bass in its final form.

Also, never use fretted vibrato (up and down) on a fretless. This will wear out your fingerboard really fast, even with flatwounds. Use cello-style (side-to-side) vibrato by rolling your finger. It sounds better that way, too.