I am quite satisfied with this little beast. It does a lovely job at melting whatever I point it at.
( First, I had some shopping to do ) Since the new head will require a new mirror bracket, and another method to hold objects to be cut at the correct height, I haven't yet given the new air assist system a tryout. I'll need to realign the optics once the new mirror mount is fabricated and installed, then I can give the new air assist system a test drive.
( Sweet! )
My interest in it was as a stepper motor driver I could control via USB from any modern computer (it appears as a serial device, and it is controlled by sending it simple ASCII commands).
1. NOw we comfirm your machine is 110V 2. Please check the laser tube has the broken or not inside. and then tell us, because we think it is mostly the laser tube broken Much apprecaite
I explained that the laser tube was intact, and I was convinced that the laser power supply was broken. They replied:
Can you please return the problem laser power supply and we will send you a new one OK?
So I removed laser power supply from the unit, and figured it was worth a look before sending it halfway around the world for replacement. Since the supply appeared totally dead, not even the fan running, I suspected the problem was something pretty basic, and perhaps something I could fix.
So I took the cover off the power supply, and found this:
The power supply had an internal connector that was unplugged! It is a locking connector too, so it had never been fully engaged at the factory. I plugged it in firmly, buttoned up the supply, re-installed it in the cutter, powered it on, and the fan spun! Thus encouraged, I fired up the cooling pump and hit the test button. Nothing. Maybe the tube doesn't strike at minimum power. I turned up the power a little and tried again.
( It worked! )
I did a few other tests, and determined that the laser was emitting plenty of power (even unfocussed, the beam burns through a sheet of paper immediately).
I wrote the manufacturer and explained that I had repaired the power supply and wouldn't need a replacement.
Next step is to replace the control electronics with something more useful. The existing controller only works with nasty ancient software on an MS-DOS PC with a parallel port.
I elected to buy it from the eBay listing, even though it cost me $40 more, so I'd have the eBay feedback process to use as leverage if the unit was DOA. I told them I preferred the engraving software, as that seemed like something I would be able to resell. I also told them I wanted a 110V unit.
When the unit arrived, it showed up in two boxes completely covered in yellow tape, pretty banged up by EMS/DHL. The small box contained the smoke fan, which was a 220V, 50Hz unit (oops). Its motor was also loose on its mounting. It also contained the software and some clear plastic tubing.
The large box contined the laser cutter itself, double boxed with styrofoam spacers. It also contained the (crushed) smoke vent pipe, an aquarium pump (for cooling the laser), a UK style power cord, two UK-US adapters, and a combination "surge suppressor"/ adapter with no ground prong.
The laser cutter was in fairly good shape after its journey halfway around the world. The orange plastic viewing window was cracked (no big deal, I planned to replace it with a clear one, the orange plastic is of no benefit for a 10.6µm laser, it just looks cool or something). There was a loose screw rattling around, and the fuse had fallen out.
The laser tube was intact, but the water cooling channels had some cruft in them (so much for "use purified water"). The water tubing also had random cruft in it.
I hauled it down to my lab, rounded up a bucket and US power cord, hooked everything up, and turned it on. The fan spun up, and the steppers zipped to their home positions. So far, so good. Then I pressed the "laser enable" button, and the "laser test" button. No result. No glow in the tube, no current on the current meter, nothing.
So I had a good look at the innards. The unit has two power supplies, one for the logic (and fan), and one for the laser. The logic supply had a sticker warning "make sure switch is set for the right voltage", and pointing to one end, where there was no switch.
I tried powering it up with the electronics access door open, and could see that the laser power supply fan wasn't turning. I got a voltmeter and determined that the laser power supply was indeed getting power. I also measured its 5V control output, but that only yielded 0.69V. Looks like either the laser power supply is a dud, or perhaps it's a 220V one.
The unit was packed with a polite note requesting that I contact them if there's anything wrong, not to leave negative feedback. I'd do this anyway, naturally. So I sent them email detailing what I'd found. We shall see.
I got back a response:
1. YOu machine is 110V verison and also all the accessary is 110V. please do not plug to 220V or it will damage
2. can you please check the back of the machine and see it is mark as 110V or the 220V
I replied that the machine is marked 110V, the laser power supply still doesn't work, and asking what to do next. No reply yet. I have found the power supply manufacturer's website.
When I bought my cell phone, it was the latest and greatest. But it didn't support tethering (using the phone as an internet connection). There was a software update for all the other phones to support tethering, but none had appeared for mine. There was some payware stuff, and I'd tried the trail versions on the train in Massachusetts, but they didn't work very well.
So yesterday, I decided to try one of the open-source ones. There wasn't a working binary for my phone, but I had the Android SDK up and running and figured I'd compile it myself for my phone. This took a fair amount of research and tweaking, but I finally got a clean compile. I rounded up the appropriate cables and my phone and uploaded it. While I was uploading, the power failed (this tends to happen when there's interesting weather afoot). I didn't know if the process had completed or not.
I rounded up the laptop and tried pairing the phone with it and connecting to the internet. I didn't know all the right parameters for this lashup, and things had changed somewhat since the last time I'd done this (I have no idea what Bluetooth DUM and PAN are, for instance). But I tried various things until I got a connection. It took a while to negotiate, but hadn't failed, so I let it be. I went to make a sandwich, and then curled up with a book by the window to eat.
When I got back to the laptop, it had made a connection. So I tried firing up AIM (a utility that doesn't use too much bandwidth) to test it out. It connected, slowly, but I didn't see anybody I knew on. I figured my ISP might be having connectivity issues too, and didn't worry about it. Then I got a message. I didn't recognize the sender, and figured it was just a scammer, but had nothing better to do, so I accepted it. Yeah, looks like junk. In Korean. But a few seconds later, I got another message. Usually the garbage messages send one URL then disconnect. This wasn't a URL, and didn't disconnect immediately. Probably someone trying to talk to someone with a similar AIM ID.
I tried using the Systran widget in my Dashboard (much less bandwidth than firing up a web browser and using Google Translate or somesuch) to make a short message in Korean, explaining that I was probably not the person they wanted. I cut and pasted the result into the chat window and sent it. I immediately got back several lines of text I couldn't read. So I cut and pasted that into Systran, and asked it to translate Korean into English. No joy, the symbols stayed unchanged. Maybe it wasn't Korean? I can recognize many of the scripts used around the world, and it did have that blocky, phonetic look like Korean, but closer examination revealed it was something else.
Oho! A mystery! The sort of mystery my language-loving friends like ayasdollz and dcseain would enjoy. Too bad I couldn't reach them. I tried launching the Facebook app on my phone, but it crashed as usual (I really wish Froyo could come out for this phone, I suspect a lot of things would work better).
I sent some English text, and received a few more lines back that I couldn't read. Maybe it was someone's secret code?
I cut and pasted some into some cryptography software I'd written and did the basic analysis on it. Yup, looked like language, character distributions were consistent with a phonetic language, and several short words occurred more than once. Didn't look like English, however.
With nothing better to do, I chose a few of the short words, pasted them in the chat window and sent them.
There was a bit of a delay, then a brief response. Also short words. Probably useful, but I was out of my element. So I sent a few short words in English.
Another pause, then a very brief response that looked to me like punctuation. Were they asking for more of my text to analyze?
I cut and pasted a couple of simple children's stories and some stuff I'd written, chunk by chunk.
Eventually, I got two foreign words back. I guessed it was "hold on" or "that's enough" or somesuch and waited.
I got back "what is". Okay, sure looks like they're trying to use my language, but don't have a lot to go on. Are they asking what language I'm using, or what? I sent back "I am speaking English."
After a little while, I got back "send more". So I started grabbing whatever text files looked likely and sending them, piece by piece.
Then I got back "Where speak English". English is pretty well known around the world, but maybe they just want to know where I'm sending from. "I am in the United States."
Another long pause, then "Not hear of", followed by "Sun up".
Were they telling me the sun is up where they are, or asking if the sun is up where I am? Sort of like the old Star Trek ep where the Horta writes "NO KILL I", with similar ambiguity.
I replied "The sun is up here. It is snowing. Where are you?" There was no reply to this, and I realized that while they can apparently puzzle out what the words mean, they don't have a workable phonetic mapping, and can't tell me something like "We are in uhzbekeestan" or whatever.
So I sent "What time is it where you are? It is 2:30PM here."
No reply. And the phone battery is running low. Apparently, the local cell site is down and I'm burning transmitter power talking to a more distant site.
( pic of apparatus )
When they showed up, I grabbed a pair of USB-PATA2 adapters, pulled the drive out of the Series 2, and hooked it and one of the new drives to the computer. I used the Unix "dd"3 command to just make a verbatim copy from the old drive to the new one. It didn't fit. It turns out that not all "80GB" drives are alike, and the one in the TiVo had a little more storage than the new one. Grump. So I pulled the drive out of the DVD recorder (which was the identical model drive), and copied that one instead. The copy completed without issues, I popped the new drive in, and it worked fine.
1fizzygeek and I
just re-watched my old laserdisc copy of the original Tron movie tonight.
And it struck me that I'd just used that phrase from the film
(I wrote that text earlier today). Hee-hee!
2PATA: Parallel ATA, as opposed to the more current SATA (serial ATA) drives. Also known as IDE or EIDE.
3The "dd" command is the "convert and copy" command. But since the C compiler was already called "cc", it got called "dd", in typical Unix harebrained naming style.
While playing with the computer tonight, I noticed a worrisome odor in the air. Shortly, I was able to identify it as the scent of a dying electrolytic capacitor. Sniffing around failed to localize it, but I figured it was the computer (which was warm and spinning its fans), its power supply (also warm), the monitor, its power supply, or the external disk drive. I wouldn't be pleased by any of these things popping a capacitor. I also checked the shelf of electronics nearby, but they didn't seem to be the source either. I fired off a backup and shut down all the other stuff, just in case.
Then I stepped out in the hall, and the odor was much stronger. Hmm, the CFL in the hall fixture had flamed out a few months ago, maybe it's the replacement. I unscrewed it and gave it a sniff. Smelt like warm plastic, but not much else. Probably not that, unless the heat was volatilizing spew from the earlier failure, but it seemed a bit strong and sudden for that. Checking fizzygeek's room, the craft room, the bathroom, and the office yielded nothing useful. But the stairway to the kitchen seemed to point the way.
I told fizzygeek what was up and she said she didn't smell anything. But when she came out into the hall, she sure did! She checked around too, and agreed that the other rooms probably weren't the source. But what was?
I had replaced the kitchen lightbulb earlier in the evening, but it wasn't a CFL, as they didn't live long in that enclosed fixture. The previous bulb had been a 100W halogen, but when I ordered replacements (they're oddballs that can fit), they sent me 230W frosted ones by mistake. So I had put one of those in. Sure enough, the globe was uncomfortably hot. Our theory is that the spew from the failed CFL had been vaporized by the heat from the monster halogen, tricking me into ignoring anything that didn't contain electrolytic capacitors!
1+1000 experience points!
People who know me will not be surprised by my next move. The ballast (called a "gear pack" by the seller) is clearly marked "DO NOT OPEN. NO USER SERVICEABLE PARTS INSIDE." maugorn and others might remember me reciting the litany "Do not open, no user serviceable parts inside, pilot lamps soldered in place, danger high voltage, warranty void if opened, etc." as I tore into things.
Well, I found out some things. The manufacturer claims that you can't just make your own lamp by buying a gear pack, because the gear pack doesn't include "the transformer". I had initially believed there was a transformer tucked into the base of the lamp, as the lamp was sufficiently large and heavy. But there isn't one. The AC leads go straight to the gear pack. You could easily retrofit any ordinary threaded-tube lamp by buying a $60 gear pack and screwing it on top.
The ballast is patented. This means I can download the schematic. It's not quite the same as the one used in the lamp, but it's pretty close. It's just a current-regulated DC power supply with a transformer-coupled starting pulse network, run off a voltage doubler. Armed with that info, and the failure mode, I deduced that it isn't the starting circuitry (the lamp failed when it was already started), and it probably isn't the current regulator (those generally work right or not at all). That leaves the voltage doubler. Not much to it, an inrush current limiter, a pair of diodes, and two big electrolytic capacitors. And electrolytic capacitors are famous for drying out and failing. So I read the specs off 'em, measured the relevant dimensions, and found equivalent units on Digikey. The inrush limiter was a house-numbered part, but a little research convinced me that it was a 10Ω, 1.7A unit or thereabouts, and such things aren't critical (it's just there to make sure that the discharged capacitors don't pull too much current when first turned on). I chose a similar unit that would physically fit and ordered it too.
While I waited for the parts to show up in the mail, I considered my other options. These days, low-wattage metal halide bulbs aren't too hard to find, and ballasts can be had from Fulham (a manufacturer whose products I like) and cheaper manufacturers. If it dies again, I can always re-use the lamp body and nice, high-temperature ceramic socket with a 70W (or more!) metal halide bulb and ballast.