I'm back from my hackspace induction at the local college-of-knowledge. It was very interesting to see the kit and meet fellow inductees and I can't wait to get stuck into a couple of little projects I have in mind. I need to get to grips with the software first though but all in good time. From the looks we were getting from one or two senior academic types in the workshop though, I did feel a bit in the way. They ain't seen nothing yet!
Burning smell coming from control box ......... check LCD flashed and will now not display ............. check Email sent to amazon vendor ....................... check!
Found the issue: Vendor is sending out a replacement board. So glad I brought from a uk supplier who I can call and talk to.
That's definitely toasted, but I'd be surprised if that was the true fault. It could be that something has pulled too much current and that's what caused the connector to get toasted. That looks like the main power input, judging by the gauge of those cables, so if something off-board is pulling too much current then the same thing might happen. Might be worth giving everything off-board (motors, sensors, LCD board, etc) a quick check over. Either way if the vendor is being helpful then you're off to a good start .
According to the vendor (in their opinion) a fault exists on a batch of the boards and it causes the board (I'm guessing its the heated bed) to draw too much current. They have encountered this with a batch of the V2.1's and they believe that the issue can resolved with a replacement board, which they have in stock and will send out to me tomorrow. I have done a brief check of all the other components and I cant see any visible issues. Your assumption about the burnt connector being the main input is correct, the one on the left in the picture with the equally thick gauge wires (and matching dodgy solder) is the connector for the heated bed. I think the solder issue is a by-product of the current draw. I was expecting to have no end of issues getting this resolved (and its early days) but so far I'm really impressed with the service being offered so far.
Decided to finally sort out my Z axis today; it seized up a while ago, but before that I was getting a lot of "wobble" in prints. Here's how the guide rod mounts to the stepper motor bracket - just a hole with a depth of a few mm, so not the greatest: So a while ago I printed these brackets to hold the guide rods more securely: So now after putting everything back together, the right-hand lead screw aligns perfectly with the motor coupler: ...But the left hand one doesn't: It's only a few mm, but it's obviously enough. So tomorrow I need to take my new brackets back off and try to get the Z-axis working again and actually let me use the printer. I think the first thing I'll be printing is a new Z-axis assembly! I definitely bought a project, not a printer. If anyone has any advice I'm all ears.
Yep, and nope. At least as far as I can tell, anyway. EDIT: I think the new guide rod brackets are just *ever-so-slightly* off. I have to go and pick up some lube for the rods today, and then I'm going to attack it again. There's got to be a better way of doing the z-axis than this...
Mine was slightly out till I did this mod: http://www.thingiverse.com/thing:921948 Its now absolutely rock solid (just a bit burny).
Got it working now - with the new guide rod braces - but still needs work. Can't say that the print quality is any better than it was before... I've just kicked off a run of 20x cable chain links, so I'll see how that goes. There's got to be a better way of moving the Z-axis than this lead screw + guide rod business...
Prusa MK2 Kit complete So I finished the build of my Prusa MK2 yesterday. Calibrated perfectly and hasn't skipped a beat. Not much to say really, the kit went together without any hassle. A little bit of cleanup on a couple of the nut retention holes but nothing crazy. It's been printing perfectly, both with PLA and a bit of ABS. I've been using simplify 3D with the Prusa supplied profile - with custom modelling (by the kids, with help) using 123D. The aim is that they'll be able to learn to model using 123D as they can use it on their laptop and iPads. I prefer higher end software, but for the kids it's very visual and a good starting point.
Looking good, Byron & Guin. I have my 3d printer specific induction at the local college booked for Friday, after which I'll be able to use their printer for my own projects. Great stuff.
It *was* looking good, until prints started losing adhesion on the bed. There was a serious amount of "blobbing" happening on a small overhanging section of the cable chain links I was printing and I suspect that the nozzle was pushing parts off the bed because too much filament had been extruded in an earlier layer. Thing is, both my z-axis and extruder steps per mm have been calibrated quite finely - if anything the extruder steps per mm is a little lower than it should be. So now I need to check that my hot end thermistor is reading the right values, level the bed again, play around with retraction values, and keep printing test pieces. I really did buy a project, not a tool.
Here's a print from my Prusa. Sliced in slic3r (Having occasional issues with the Simplify 3D and it's not supported), and printed in PLA in a little over 5hr @ 0.1 layer height using all the default settings. http://www.thingiverse.com/thing:1398242
