Monday 5 December 2011

Rotary Speaker - update

Some update on the rotary speaker project.


I finished the enclosure and decided it needed covering.


Blue vinyl table cloth.


Control panel - photoshop, printed on paper and laquered onto box.


I need to clean up the front a little. I have a temporary plastic grill in there until some wire mesh comes my way.


It's looking a bit 'Toys 'R' Us'.


I need to wire a socket for the power supply. The pot on the back sort of fine tunes the speed. One control would be better, but until I can build a proper speed control, this allows slower speeds. I did build a very simple PWM circuit but the motor actually makes too much noise as it pulses on and off. so either I need a more sophisticated circuit, or an enclosure to silence the motor? Anyway, at this stage it works as required, so aside from a few cosmetic jobs, it's more or less finished.

Audio/video to follow

Saturday 12 November 2011

rotary speaker

Been working on a rotary speaker project.

I spent a while experimenting with drive bands and pulleys before settling on a coffee cone/dripper attached directly to the shaft of an old motor from a tape deck.



A paper cone sticks out the side of the coffee dripper

A sawn-off funnel over the speaker channels sound into the coffee cone spinning above.


Using an old Fostex speaker.

I'm now thinking about how to finish the enclosure and mount the controls. I have a PC fan controller to adjust speed but it only has an affect from 12V down to about 6V - it needs to go down to about 3V for slow rotation. I might build a PWM circuit to control the motor.

Here's a video test drive:

Saturday 17 September 2011

My Junk Guitar - bake 1 - paint job

Been lacquering and waiting for it to cure.

In the end I went with a chocolate brown and sealed the gold flakes with clear overcoat.
not a great shot - i hoped the flash would make the gold sparkle more.

I gave the pick up shell, volume knob, bridge screws and tuners an ivory coat - the pure white was too harsh. The ply body has been bound with a few layers of wood banding tape and sealed with more clear lacquer.

first assemble

Though part of me thinks the natural wood had its charms, I'm quite pleased with the results - just the right amount of cheese. I'm happy how the logo turned out - bent from wire and sealed into lacquer.


The name is "Daizo". The "zo" coming from Z0-3 - the source of the neck, and the "dai" meaning big. However combined this way, they sound like "Daiso" which happens to be the name of a very well known 100yen store (dollar/under a pound store). A fiiting tribute to the 'build it cheap'.

The volume knob came from a tube of toothpaste. It has a nice 'tri-star' thing in the center.

Finally, here's a shot of the horrors lurking beneath the facade. I still need to make a cover to go over the electronics.

I've discovered the lacquer could have done with more curing as it's rippled in a couple of places under pressure from attaching things. I'll likely take it apart and touch it up.

Hopefully I can post some sound or video files shortly.

Monday 29 August 2011

Junk guitar - bridge and pickup

A few small jobs done.

Reinforced the tail-piece with an aluminium blank. this should make it more rigid and prevent any give under string tension:

much better now !

I also routed out the hole and cavity for the pickup. Not the most precise cut - I hoped to get the edge much flusher with just a hair's width of space between the pickup cover and the body. Unfortunately the rounded corners came out a little wider. Still, maybe when I lacquer it, the space will be filled slightly?

You can just see the wider margin at the corners from this angle:


The grain looks nice from here!

I also cut and filed a new saddle. I used aluminium, but maybe I'll try some steel or brass later on and see if there is any discernable difference to the sound.

I wired the pickup to a lead and plugged it in. It works and sounds promising. I'm still wondering about electronics, but I think it's just going to be a single volume pot and no onboard tone control - that will keep the design simple and spare and save me from lapsing into buying any new parts. That would defeat the object since this project's about re-fried scrap all the way!

Here's a view of the whole thing as it stands. Hopefully the onlooker will note that the horn of the body echoes the shape of the headstock...


Starting to think about the finish. The grain on the front is quite pleasing. I think the patterns work well with the shape of the body. I could try staining it to bring that out more, but being ply, the edges will need some treatment.

On the other hand, I'd like to try some new lacquering techniques and this would make a good practice piece. Recently, in my rummaging, I came across some small sachets of gold flakes. This is real gold that, I kid you not, came free with beer. In less austere times, there was trend here in Japan to decorate food and drink with gold flakes. Perhaps it still goes on? Not being one for ostentation, I put them aside and forgot about them. They must have been sitting in the kitchen draw for over 10 years. I'm now thinking these could be employed for a sparkle effect over dark blue, brown or black.


Saturday 27 August 2011

Junk guitar - checking the bridge

I fitted the bridge earlier in the week and strung the guitar up. I thought I should leave it for a while to see how it behaves under tension. So far all is well on the wood front but I think some attention is needed for the tail-piece - a lot of re-tuning was needed at first and I suspect it wasn't just the new strings. I believe the tail-piece has too much give in it. After about three days it seemed to settle more, but I've decided to insert an extra piece of metal to provide more support.

before stringing. the ply facade sits over the bridge so it's slightly recessed.

strung. the black marker pen is just to see if anything drifted

so far, so good

While the guitar was settling under string tension, I began work on the pickup, or pickup housing to be precise. One thing that I will have to buy is wire for winding the pickup but so far I haven't found a ready supply. I will have to either order some on line or take a trip across town to Akihabara, and hope to find some in a shop there.

Anyway, I've begun construction on what will house the pickup and allow height adjustment. This is a actually half of a plastic pill box with a hole cut out. A sheet of aluminium mesh sits inside and acts as a cover. You can just fit a humbucker in there and I used an old one for guidance when making the housing. I expect to make a single coil for this guitar but it's good to know a humbucker will fit in there should the need arise. I should get some more photos of the construction, but here's one for now:
I think it looks like some bizarre cross between a transistor radio and an electric shaver circa 1963 - very Pifco!
(that's good)




Saturday 20 August 2011

Junk guitar - progress - adjustable bridge

I've been working on the bridge. I wanted something adjustable in order to set the action and intonation. As I don't have many tools for metal work (no milling machines here!) it has to be a wood job. Fortunately, I found an old box made from something that seems hard and tropical and decided to use that.

My initial idea was to construct something akin to the bridges found on archtops. After a rummage through my nuts and bolts I realised I didn't have anything that was really suitable, but it then dawned on me that I could use a couple of the saddles fom the ZO-3's original bridge. These are the regular sort with worm-screws for height adjustment that are found on strat-type bridges. There were six on the original bridge, one for each string, but three of them were so badly rusted up that their worm screw couldn't be removed. My idea however only requires two - one at either end of the bridge. I'm not sure if it really provides sufficient strength, but the bridges on a couple of my old Japanese twangers are similarly raised by just two, not so heavy-duty, bolts.

I found some bolts with grippable heads to replace the worm-screws.

Hopefully these photos show how it all works:

side view - the saddles from the original bridge are now upside-down


the wooden blank


as seen from below - two of the original saddles - one at each end


from the front


and from above - the plastic saddle is temporary and will probably be replaced with something like brass. there is still some shaping to do once I see how it works with the body

There was also a tail piece to make, plus a bracket for the scale length adjustment. For these I used some sheet steel from the casing of an old Technics hi-fi amp.

cutting and bending the tail piece


slots for strings


still needs a lot of polishing


testing the bridge


the bridge and tail piece are fitted to a block of cherry wood


there's about 3-4 mm of vertical play at the bridge which means I can get an acceptable action at the 12th fret - hope that's still the case when it's fully strung and up to tension!


checking the alignment down the neck

Next step is to glue the bridge block to the body block, I'll probably add some dowels for extra strength. After that, I'll be routing cavaties in the plywood facade to sit over the bridge. I'm thinking the electroncis will be entirely mounted into the facade - that way it can all be removed as one unit which may make maintenance easier.

Thursday 18 August 2011

Junk guitar build - progress report

I spent a while deciding what to make the body from. As I intend to avoid purchasing any materials there are going to be some restrictions on what I can do.

I'd already conceded that the body would somehow be composite and expected to make a blank out of several sheets of ply. However, I found I didn't have enough offcuts of sufficient size to do this as expected. What I did find though, was a nice piece of cherry - very hard and solid but still too small - it was the end of a plank.

However, I then got the notion to build the resonating structure of the guitar by mounting the neck and bridge to the cherry wood and fitting a facade on top. I did a google search to find out if, a) cherry was ever used for guitars, and b) whether anyone else had built a similar instrument of plywood facade over a solid block. I knew a little of the Danelectro construction with masonite and suspected that some archtops/semi-acoustics may have been similarly comprised, albeit with a full structure encasing the inner block. My idea though, was simply to have the solid block fronted with a facade.

Here's something I found on the net - Eric Mecum's plywood guitar


nice!

http://img.photobucket.com/albums/v118/turquoisemoleeater/guitars/EricMecumplywoodguitar.jpg

The above guitar is pretty much along the lines of what I was envisaging and I was enboldened to continue. By the way, you can check out more of Eric Mecum's guitar builds here: http://www.ericmecum.com/?page=guitars

I also found cherry has been used but not widely - it seems that the standard mahogany, ash and alder being known quantities has led to folk having little desire to stray from the norm - the builder/player knows what they're getting with these. Still, no problem for my project - I barely have a clue how it'll end up and I'm trying to use whatever's to hand, so cherry it is..

I went ahead and cut some parts...


rough cutting the plywood facade


the hardboard template and the plywood facade


lined up ready for routing


the parts - neck attached to cherry wood base


a design tryout with paper and toothpaste cap


by products - the kids get involved



Monday 15 August 2011

Build a Guitar from Junk

I finally have something to document on this blog - a 'build it as cheaply as possible' guitar inspired by a neck I already had lying about waiting for a home. The neck came from a Fernandes "Zo-3" that I originally picked up from the junk corner of the local Hard-off store.

The body and many of the fittings (bridge, tuners, etc) have degraded somewhat, probably as a result of storage in humid conditions, but the neck seems surprisingly intact. Here's a photo of an intact ZO-3 (not mine):


http://commons.wikimedia.org/wiki/File:Fernandes_ZO-3.jpg

When spoken, Zo-3 becomes "zou-san" and is Japanese for elephant. Perhaps you can see the resemblance in the design? (picture the guitar in playing position).

The following principles will apply:

- Use existing scrap, junk, parts, bits and bobs, etc that I have lying around the house
- Allow aesthetics to dictate the flow of project (more below)
- Learn something new - in this case that'll probably be winding my own pickups
- Have fun

My Yes/No of Aesthetics

Yes - the guitar should appear to be:
- Space junk mated with agricultural machinery
- Earth bound but beaming out to cosmos
- Transmitting the unknown

No - the guitar should not embody:
- Machismo
- Death
- Auto-industry(?)
- Rock without any roll

(will probably add more to the above as the project progresses)

I sketched out a few shapes and used photoshop to get a full-size template:



Next step is to make a proper template out of ply or hardboard. This will be used for routing the body.