Multidisciplinary Project

What at first was going to be just a little cleaning and polishing has become a monster of a project. After a good hard think I decided to bring my 20th century CNC lathe into the 21st. First up is a stand or bench to hold all the bits together.

The picture was taken last friday and I've spent a lot of time on it since then so it's mostly finished by now. You can see the lathe in the background. It has lost it's control cabinet and I've taken it to pieces (right down to individual screws) to clean and adjust it. While I was at it I've painted some bits black beacause, well... because I think a black machine looks the part. Old Henry Ford and I would've agreed on one thing>> You can have it any colour you like as long as it's black!

Here's a list of improvements I want to bring to the machine.
- Replace the outdated DOS platform by a modern computer running Linux and EMC2. If anyone reads this and they have experience they'd like to share about EMC2 I'm keen to learn. I'm especialy troubled about the HAL component of EMC2.
- Fit and wire up a breakout board so the computer can talk to the lathe.
- Replace the stepper drivers to modern microstepping Geckodrives. I've bought these allready.
- Possibly replace the Slo-syn stepper motors with modern 200 step NEMA23 motors.
- Fiddle with the spindle drive circuitry to enable computer control of speed and start/stop and reversing. This bit is underway.
- Figure out an encoder arrangement on the spindle to enable "spindle synchronised motion" like threading.
- Add a coolant pump and attendent circuitry. Under computer control no less.
- Fabricate a coolant/chip guard on the front of the machine.

I think I'll be busy for a while yet.

One Last Item

Well, I pretty much finished the parts I could make over here for my steel guitar. Which means they're all in a little box winging their way to Canada as we speak. A couple of posts back I showed you the core for a pickup that I had made. All I had to do was wind crap loads of very very thin wire onto it and it would become a functional guitar pickup. I don't know if my fingers are too big or the wire is too small but after three tries I began looking for an alternative. I ended up using the coils from 4pole relays that I found in one of the scrap heaps. Then it was just a matter of making a case and pole pieces for it and ta da....pickup!

Seven more days in the pit and I get to go home for a couple of weeks. That will be my second to last run out and then I'm done. No more New Caledonia for me, but you know four years is more than enough.

What Good Is a Guitar Without a Pickup?

Continuing on the steel guitar project. Steady as she goes. I'm off for a couple of weeks back home so this is as far as it's going to get for now. But, going to Canada will allow me to buy bits and pieces that cannot be found at any price on the island >> like flatwound guitar strings for example.

Anyway, here's the progress of this last week. I made a Pickup bobbin (on the left) which, once I've wound thousands of turns of copper wire and put magnets under it, will allow the guitar to speak electronic with an amplifier. Middle spot is held by the not yet completed aluminium cover for the pickup. Last but not least, weighing in at mere grams, was once a scrap bit of aluminium but is now a super light weight, racing style, formula 1 inspired >>>>>>> ashtray. Beacause I can, as you do, and all the others apply.

Business as Usual

Unfortunately this is not a finished project. Took a picture for shits and well, now I guess I better post it online for no other reason than it's here. So, they're parts for a console lap steel. Have a look by clicking the link, it's very similar but with just one neck and no pedals. Anyway, now that the parts are half way polished I just thought of a modification I want to make so it'll probably not look like what's on the picture in the end.

And now for something completely different! I've been using crappy old computer speakers to plug my Ipod into to get some tunes going in the shop when I work alone. Well, they sound exactly like a rat stuck in a tin can maybe even a little worst. I decided to make something with a little more oumph. I procured speakers out of a Land Rover that's being scrapped and a shipping crate for bearings, oh and a door handle from the Land Rover and the amp out of the computer speakers. That's what I came up with.

 And here it is with its Steinway paint job. Can't remember where I read this but apparently when Steinway delivers a piano and they make a chip in the paint the "technicians" will use a Sharpie pen to cover the spot. If it's good enough for Steinway and sons then it's good enough for me. So I just went ape ship with a felt tip pen!

The Motor That Pushes the Speakers

As you've seen I've made fancy speakers. I needed something equally fancy to push those babies to produce really sweet sounds. I've always liked tube electronics ie: hollow state, thermionic valves, etc. I've even built a couple of tube amplifiers with scrounged parts. I found a site where I could order a complete (well mostly) kit to build a copy (or re-imagining) of the legendary Dynaco ST-70. I bought the kit thinking it would provide me with entertainment during my vacation. I haven't been the manufacturer of the kits for a good reason. Their shipping is horrible, when it got here there were parts missing, their customer is next to non existent, I've had to scrounge the internet to find instructions that should have been supplied with the kit. That being said the amplifier is mostly done but I'm still waiting for the actual tubes to get it going.

First picture, just started. I screwed and bolted all the bits to the chassis (the metal box that looks like a cake pan). The wires come out of the three transformers and one choke that are the heart of the amplifier (if the tubes are its soul)

That's me working away on it in what has come to be known as my laboratory (basically a 3' X 3' square of floor between boxes and other sundry storage in my sister's basement). Notice headphones supplying laughs and music while working. I took the picture with my butt. Not a joke, I plugged a bit of wire into my camera and soldered a switch to the other end. The switch is under my bum so I could trigger the camera without the wire being apparent in the finished picture!

And there you are, mostly complete. Well, the circuit is complete anyway. Like I said, I'm still waiting for the tubes so I won't know how it sounds until I come back in late January.

New, old speakers

I made these more than six months ago and they've been out of storage for only a couple of days. At most I've played 5 or 6 albums through them. In short, for the price, they sound absolutely amazing. If you want to build yourself a pair do a search for Dayton III. You'll find plans, parts lists, sources and the crossover schematic. I went and put a can of cider in the picture for scale.

The Warm Glow of Hollow State Electronics!

Yeah, you read that right! If the early transistor slingers where all hoopla about their new fangled germanium switches which they called "Solid State" we must conclude that the grand old dame, miss thermionic tube, must be "Hollow state". The story of this little project started long before either of us was born. In a country school science lab sometime during the fifties students where building shortwave radios from little kits their teacher had ordered from a company called Graymark. One of those kits survived, unassembled and untouched until young Patrick found it in the cupboards of said science lab and asked the teacher if he could have it. Tubes having already passed into legend by the 90's the teacher accepted and Pat went home to build his very own shortwave radio. Unfortunately, the radio did not work, though from what I hear it could give nasty shocks when touched!!!

Three or four years ago Pat asked me if I could have a look at it maybe get it working or at least get it to do some kind of noise. It was a rather nifty circuit. A regenerative receiver for those who speak the language built around a 12AT7. Also included where a 35W5 as rectifier and a 50C5 as audio power amplifier. If you heard about the all american five radios then you know the first problem with this one. Yep, that's right no transformer to isolate the incoming AC therefore the chassi was live!!!! No wonder one could contract a nasty shock! The second problem was a burnt out component, unfortunately one of those tube era components that now cost a small fortune, the rest of the world having moved on to transistor technology in their quest for massed produced, disposable electronic devices. Conclusion: radio cannot be fixed unless we throw money at it.

A few weeks back Pat and I where discussing bass guitars and amplifiers and how it would be nice to have a small tube amp to practice with at home. I mentioned that we could probably build a small amp out of his little radio that had been gathering dust on the top shelf of one of my bookcases for a couple of years. Eureka! Let's make a 1.5Watt tube monster (hahaha!) as a practice amp. So we gutted the small radio keeping all the good bits out of it. Elaborated a schematic out of ideas found on the net and spent a nice sunday afternoon breathing rosin flux fumes while soldering parts.

It's not quite done yet and I'll show you pictures of the finished "thing" once we get it going.

Testing one... two...

Here's what I've been up to lately. I've taken a fancy to record things! Be that nature sounds or musicians (hear that kiddo). My budget for the venture is close to nil. I did buy a USB analog to digital converter so I can put whatever I record on the computer and manipulate it. It wasn't expensive but microphones (good ones) are bloody expensive. So, ever the fountain of knowledge I consulted the 'net to see what others had done. Order (free samples) integrated circuit chips (INA217) from Texas instruments to build microphone pre-amps. Done. Dumpster dive the Videotron dumpster for good quality shielded cable. Done. Scrounge bits of pipe and stainless screening from the shop. Done.

So far so good, not a penny spent on the microphones! I broke down and ordered 5 microphone capsules from Digi-key. At 2.72$ each they didn't break the bank! They're the tiny black things on the penny in the pictures. WM-55A103 Panasonic cardioid microphone cartridges if anyone is interested. I intend to modify them using the Linkwitz mod so that they are closer to professional standards.

The top photo shows a stereo pair I'm building. One is assembled and one is in pieces so you can see all the little parts spread out. The bottom one is much bigger and it will be a variable polar response microphone with a proper shock mount and everything! They're not done yet. The stereo pair is all stainless and aluminum so I'll leave them in the sandblasted state. The big one's main tube is just plain steel so I'll have to paint it or else it'll rust. I think it will look nice what with a black body and the shiny aluminum end caps.

It's funky to look at what the camera did to the screening!