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Homemade Robotic Arms for CD Duplication?
LA Kings Fan writes "I have this current gig of a job which requires me to make numerous copies of CDRs (in the thousands). Since it would be ludicrous to sit in front of my computer to remove a burned CD and put a fresh one in everytime, I've looked around for better, more sensible solutions. There are two alternatives: CD Duplication Towers and Automated Duplicators. They both have their advantages but are very costly. The cool thing about the automated duplicators is that the burning process is automated by the use of a robotic arm which replaces the burned CD with a fresh one. This is neat, so I was wondering if anyone has attempted to take this concept a step further by essentially building their own robotic arm for their burner on their personal computer. Is this feasible? Can a robotic arm like this be created from off the shelf parts? I'm clueless when it comes to this engineering stuff, so any help would be appreciated."
Don't over complicate a simple problem. I master CDs for a living. There are a ton of CD duplication houses out there. It is not that expensive. I've done a thousand with cases, screenprinting and distribution for about $1,500 and a week turnaround. Do your clients a favor and do it right and fast.
By the time you finish planing and building you robotic arm the whole project could be done. If this is a "gig" as you say your getting paid to do a service. Do the job you were hired to do. Don't go on a tangent just to impress us here.
I find doing a good job well and fast much more impressive than flashy unnecessary extras.
-- No Comment
As some of you may know, I have pondered how to build a homebrew CD changer - something to allow you access to all (or most) of your CDs at one time. This problem is difficult, but not impossible.
CD Duplication is much easier.
Think of device as an "arm" that can move linearly on one axis, and travel up and down by a small amount on another orthogonal axis. So, basically a 2 axis pick-and-place arm.
Place two spindles on either side of the burning drive. One spindle is full of blanks, the other is empty (to hold burned blanks). Line the centers of the holes in the CDs up with each other, as well as with a CD in the drive tray with the tray ejected, so the all the holes fall perfectly in line. Mount the drive and the spindles down in some manner (screws, glue, something).
Now, you need to build an arm - a couple of cheap RC servos and some aluminium square tubing, maybe some threaded rod, so that it can move up and down, and move in and out along the line of the holes. Build a forked picking appendage out of aluminium tubing, with the ends of the fork bent down at a 90 degree angle - the clearance between the two "tines" of the forked tubing should be wide enough to clear the spindle. At the ends of the tines, attach cheap suction cups drilled through - seal them well to the tube ends. The fork needs to have a tee split off of it that will connect to a piece of silicone tubing that runs to an aquarium air pump - this tube will connect to the pumps air inlet (the pump may need modifications for this) to form a cheap, low cost, but efficient "vacuum pump".
The arms servos can be connected to a BASIC Stamp with appropriate driver software and hardware - the stamp can be programmed to simply accept commands to move the servos properly to certain amounts as sent over the serial port (via a MAX232). The Stamp will also need to be connected to some 120VAC relay (12 volt coil, 120VAC contacts), or a 120VAC solid state "relay" to allow control of the pump. Then code would have to be written to do the following:
1. Move the arm to the full spindle. Turn on vacuum pump, and lower fork to "suck up" the CD.
2. Lift arm, eject tray, position the CD, turn off pump to drop CD, inject tray.
3. Burn CD.
4. Eject CD, turn on vacuum pump, lower arm, "suck up" CD.
5. Move arm to second spindle, turn off pump and drop the CD - goto step 1.
Remember that at step one, your pile shrinks, and at step 5, the pile is growing, so you would need coding to account for that.
At any rate, such an arm could be easily built, probably for under $200.00 if you shopped carefully (and already had the burner).
Of course, if you don't have any experience building such devices (basically, homebrew robotics and electronics, plus coding) - you won't get very far, and I would have to concede that it would be more worth your time and money to purchase a machine, as other posters have reccommended...
Reason is the Path to God - Anon
I'd agree that it can be better to use CD-Rs (if it fits your situation), never said it wasn't - There is a time and a place for everything.
What I said was that it was crazy to waste the time and money on a "rubber band" solution. I think it's stupid to try and spend time and effort on developing your own automated system that it will end up costing you as much or more as a purchased one. Especially for the original poster, since he flat out states he has no engineering experience.
He should either get them done professionally, or buy a 10 disc burnstation. They aren't THAT expensive and you can quintuple the performance your $6 an hour drone gets, or even better, make it easy enough that an employee you already have can do it - no new employee at all. It would take someone about 30 minutes of their day to change the 10 disc burner 8 times. Why pay someone to sit there and burn cds if you already have an employee? Or hell, do it yourself. The money you save in ease of use and wages will pay off the burnstation in a few weeks/months.
(If the original poster is in a Uni environment, it might be worth it to get a student worker to do it, because, if student workers are anything like they were when I were in school, they are basically free labor and have a minimum amont of hours they must put in for their work-study, anyway.)
And furthermore, did you know that pressed CDs are more likely to fail and have errors than CDRs? I bet you didn't know that. Well now you do and it was a free as in beer tip from your bud Steve in Taiwan.
The place I go through error checks all CDs. They have a 10% either way margin of error on the size of your run because of this.
I've never had a CD fail on me, ever. Never had anyone complain to me, either. Or one of my associates mention any of their discs failing. All my cd's are audio, so maybe that makes a difference. I don't deal with software, can't much about that. When I worked at a CD store, I also don't recall anyone ever returning a CD because it didn't work. Once someone did return a alternative cd because it actually had opera on it, though.
And, if you think you break even on a stamped disk at 1000 pieces I don't think you know what you're talking about. That might have been true five years ago when CDRs cost more than a buck. But guess what . .
The thing is, I'm putting out music CDs. Not software. I can't have them be CD-Rs, because that looks cheap. They have to be silver backed, they have to have silkscreened faces. Think about it, you plunk down ten or twelve bucks for a cd, open it and it is a cd-r with one of those sticker labels - are you gonna think you got your money's worth? No.
I don't care if it costs me 20-30 cents extra to look professional (at 1000 the price dips down to about 0.60 per disc)- it HAS to. If looking professional means the difference between me selling out a run and only selling half, or me being able to charge $6 for something that looks shoddy and $10 for something that looks good, I'm gonna go with professional-looking. I'd imagine it is good to look professional in whatever business you're in, too, but maybe not - I don't know your business.
I also like going through a company because, well, I do not have a steady employee. I don't put out 5,000 cds every week. I put out 5,000 one month, 1,000 two months later, 2,000 a week after that. It's not steady. I can take my master to a place on monday and have my 5,000 cds by friday. I couldn't get that turnover with an employee burning them in my office, and I don't want to pay someone to sit around when I don't need them, or have expensive equipment (and 1,000s of blank CDs lying around to go along with the regular CDs). I also don't wanna have to hire someone just for a weeks worth of work, nor do I wanna deal with a temp who is just going to mess things up somehow.
For _me_, getting them done is the way to go. They also handle getting the lyric inserts printed, shrinkwrapping them, etc. That way I don't have to sit there and put the inserts in a few thousand CDs, then shrink wrap them, nor do I have to pay someone an hourly wage to do that. This changes the dynamic of your estimates BIG TIME. How much more would it cost me to pay someone to do this, and how much longer would it take? It already would take me longer to burn them than have them made.
If you can do CD-Rs, and you're doing small run or have plenty of time to wait around, I'd say a burnstation is they way to go. Building some sort of contraption seems like a recipe for disaster, and if it's not, please post details about the contraption you built and how much time/effort/money you spent building it, compared to how much it saves you and how much it would have cost you to just buy an off-the-shelf automation solution.