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It’s better for everyone if you can get it fixed on your own, but if you do get really stuck, we’re here to help. :)
Hooray! And, *thank you* for pointing out that the directions were not clear. (Hopefully, it will be a better experience for the next person to come this way.)
Hi John,
You’re on the right track. Yes, use the difference menu option to create your cutout shape. To fill a “funny shaped” path with lines, you may have better luck with the Hatch Fill extension, rather than the squiggly hatch; it handles a wider variety of shapes.If that’s still not working, try first selecting the shape, and then filling it just with a solid color, to show you where Inkscape thinks it should be filled in. That might help you figure out if there’s a bigger problem with the shape.Yes, 690 ohms sounds very low. It definitely sounds like there is something wrong there. However, it may be hard to diagnose, because it seems as though something has failed partway– not all the way open or shorted –either of which would make this pretty straightforward. In the absence of any better guidance, and if D12 seems to be working more-or-less correctly, I’d suggest replacing D21, as it seems like that is the likely point of failure.
If you’d prefer, you might want to consider sending it to us for analysis; we’d be willing to replace that LED for you, and figure out what the problem is otherwise.As far as the faceplate without a hole goes, you may not need one. A common procedure when installing the rear-projection plate is to use the original opaque clock face to cover the big hole in the other side. Just use it instead of the washers on that side.It sounds like you do not have the Time library installed correctly. If I remove the Time library from its correct location, I get that same set of errors.
Your “libraries” folder should contain folders called “Time” and “alphafive,” and you should restart Arduino (close and reopen the program) after double-checking this. Both should show up in the Sketch > Import Library menu, and you should not import either.You can approximate this as an RC circuit. http://en.wikipedia.org/wiki/RC_circuit
If 12 V draws 4 A, then you could pretend that it’s a 3 ohm resistive load.Then V(t) = V_0 exp(-t/RC), or V(t) / V_0 = exp(-t/RC)Taking the natural log of both sides,ln(V(t)/V_0) = -t/RCFor your case, we are solving for t=0.5 s. V(t = 0) = 12 V, and V(t = 0.5 s) = 10 V.Then, ln(10/12) = -0.5 s/RCApproximately given by -.182 = -0.5 s/RC, or RC = -0.5 s/ -.182 = 2.74Putting back in R = 3 ohms, that gives C = 2.74/3, or about 0.9 F.So, you’ll need roughly a 1 F capacitor rated for at least 12 V, or in practice 1.5 X higher just in case the actual voltage goes higher. It’s actually common to find capacitors in this range (1-5 F, 16-24 V rating), manufactured for use in car stereos, in the range $20-$100.Capacitors are not like batteries. They do not maintain a fixed voltage when discharged, but instead decay exponentially. Look at how an “RC” circuit discharges for an example. So, what you really need to know is how far down that curve you can go. Is 11 V an acceptable endpoint? Or is 9 V? Or do you need 11.5 V? Once you figure that out, you should be able to find how much capacitance you need to let you stay at or above that level for 1/2 second.
I must apologize; that description for how to upload the firmware was utterly terrible; it was more applicable to the v1 firmware than to the current process. I’ve updated it to say rather explicitly what you need to do. First, install the Alpha Clock Five library for Arduino, and then open up the example file from the menu to upload it.
Please give that a try, according to the newly updated instructions, and let me know if you have any additional trouble.If it was working properly to begin with, you can be assured that all of the LEDs are facing in the correct directions; they don’t spontaneously reverse direction. And, if you really need to look, the right way to verify the orientation is by looking at the flat face on the collar of each LED, rather than at the internal wireframes; those vary between different types of LEDs.
Reflowing all the solder joints is usually *not* the way to find a problem, but it can easily create new ones if you overheat the LEDs, damage the traces, or create dry joints out of good ones. Instead, try to look and see where the problem actually is, and only resolder where absolutely necessary.I’m not sure that I understand what you mean by “flipping and flopping.” You should measure the resistances with the power off; nothing should be changing while you do that.If LED D21 is very dim, that could also point to a possible connection between lines LED1 and LED2. Please check the resistance between these lines; they should not be connected.A youtube video would probably not be helpful. Checking the resistance between the LED lines would be. :)If you have a multimeter handy, you might check to see if there’s a short circuit between lines LED1 and LED2, or between either of those lines and LED10. There could be a solder blob or stray wire somewhere causing the problem. I’m having a little trouble following most of your specific LED locations, but that would be my guess from your description on the red ring.
The Zerohm jumpers really are a specific type of wire jumper. They are not actually resistors; we did not choose them “instead” of wire jumpers. They are inexpensive, easy to count out, convenient, easy to identify, and their shape makes step 33 of the instructions pretty easy. Without that “bead” in the middle, we’d need to figure out some other way to hold them in place, and make sure that there was enough length on both sides.If just one of the ten LED lines is not wired up correctly– for example, if a solder joint has failed –you will start to see these kinds of funny lit-up patterns. And yes, it’s an effect of charlieplexing.
When you’re describing the LED positions, I’m not sure if you’re describing the locations of the LEDs that are lit up, or if you mean the opposite– the LEDs that light to indicate those times. But in any case, you should check each of the vertical LED line jumper wires, and especially the connections at the microcontroller and the resistors– those are the most likely places for the issue to be located.A very thin cylindrical ring is a lot like the center slice through a sphere, so the Eggbot can probably work okay on the surface, but I’m really not sure about the engraving part. The Eggbot is meant for drawing, and does not exert the kind of downforce that you would need to make a good mark with a handheld scribe-type engraving tool, and cannot support the weight of heavier, traditional engraving tools.
Two things that *might* work well, depending on budget and requirements: Our own diamond-point engraving tool– normally meant for hard surfaces like glass and stone –could actually be used to mark anodized aluminum, on a low vibration setting, with a slow travel speed. However, the marks will not be much finer than those that you get with an extra-fine point Sharpie marker. High-speed, lightweight engraving tools, such as the Turbo Carver could be used to good effect and make very fine lines, but cost a fair bit, and will take some work to mount to the Eggbot.The added weight is slightly inelegant, but a fine solution. :) You may be able to add a little extra weight *under* the lever to make it a little less obvious.
The danger of too much weight on that side is that it will not return up when there are a lot of balls in the input guide.The test that we use– before it ships –is that you need to be able to place a ball, at zero speed, right above where it says “MAN,” and it should work *every time* for dozens of balls in a row. It’s a pretty rigorous test.
Now, what we have found is that when our Digi-Comps have been sitting still for a few days, they tend to stiffen up a bit, and we do need to “exercise” the start lever for a little while in order for this part to work reliably. The stiffening is because the wood relaxes over time and possibly with humidity changes. The likely sources of friction are as follows:1. The hole through the center of the start lever vs. the brass pin2. The start wire through the hole in the start lever3. The start wire through the hole in the ball release.I’d suggest applying a little bit of force as you wiggle these connections separately, to loosen them up. For example, turn the start lever a few times, while pressing with modest force towards the four sides of the board. And as I suggested above, firmly hold the points where the wire meets the start lever and ball release, and apply some pressure to loosen up those holes.Good; that sounds a lot better. I’d imagine that more humidity would be a bigger issue, as the wood pieces may not slide so easily.
For T4, do you find that it “clicks” when you slide it from one side to the other? If so, you may find it helpful to very slightly loosen the four wingnuts, turn the Digi-Comp on its RIGHT side, and tighten them again. If it does not “click,” but is just a little “slow,” do not loosen the wingnuts. Put one finger on the pivot pin head to hold it in place, and turn the switch back and forth a few dozen times to loosen it up.For the start lever, put your finger on the spot where the connecting rod meets the START lever, and apply gentle pressure at that location while gently moving the lever through its full range of motion, several dozen times. We’ve found this to help loosen things up.
