Electronic Kits, Who's are the best??

I am looking to buy a set of boards to build my repstrap and I found a guy on ebay who can supply the lot, but when I was checking his feedback I noticed the only neutral feedback he had was from nophead00. I think you are a respected member of this community and so was wondering who you would recomend as a supplier. I cannot afford to make a mistake on this one as my budget is already hard pressed.

Don't get Gen 3. More hassle with wiring and it seems to have serial communication issues. RAMPS is probably the best choice now. The Arduino Mega 2560 is $65 (US) in most places and cheaper in ebay. If you're on a tight budget, the shield board can be bought bare, as a kit in addition to fully assembled. You can even make it using a stripboard. Ultimachine.com is a good source.

+1 for ultimachine RAMPS

one of the best things about it IMO is that it's a single board and modular. it would be pretty easy to replace each individual component as opposed to something that is multilayered and surface mount soldered.

I give my vote to RAMPS as well. It's so small that you can strap it almost anywhere on your machine with a couple of plastic ties. I've put together five of these in less than three hours!

Ultimachine is an excellent vendor too, and they offer the options of buying fully built, DIY kits, and single components. Very cost effective if you already have many of the components.

Anything but Gen3! The nasty hack of driving the extruder stepper (the most critical torque-wise) with dual h-bridges instead of a proper current-chopping driver doesn't work very well. And that ignores the comms issues. If you already have it, it's not worth completely replacing though. Just buy another stepper driver board (pololu or whatever) and use that instead of the extruder's h-bridges.

---

--
I'm building it with Baling Wire

jgilmore Wrote:
-------------------------------------------------------
> Anything but Gen3! The nasty hack of driving the
> extruder stepper (the most critical torque-wise)
> with dual h-bridges instead of a proper
> current-chopping driver doesn't work very well.
> And that ignores the comms issues. If you already
> have it, it's not worth completely replacing
> though. Just buy another stepper driver board
> (pololu or whatever) and use that instead of the
> extruder's h-bridges.

I have done this but it's still not good enough. I can't run the Pololu's at 1/16 steps for the extruder and I had settle for 1/2 step in order to get retract/restart to work right. I also had to limit the x and y to 1/8 steps and leave the z at 1/2 steps. This allows me to print at 20 mm/s reliably. I know that the RAMPS and Gen 3 share the same CPU but for some reason, I can't step as fast with the Gen 3 as others can do with their RAMPS electronics.

Thanks very much for your help. I checked out their website and they are out of stock of everything. Do you know any other reliable vendors?

That was fast! I just received my order after they went back in stock about a week ago.

brnrd: It sounds like you're running into firmware limitations. Which firmware are you using?

---

--
I'm building it with Baling Wire

I have two fully built RAMPS for sale. Send me a message if you are interested.

jgilmore Wrote:
-------------------------------------------------------
> brnrd: It sounds like you're running into firmware
> limitations. Which firmware are you using?


Right now, 20101221 reprap host firmware. it seems to run well with the host on Mac Leopard or Windows XP. But above 20 mm/s, it can't keep up when going around small circles or small segments.

Unsurprising. The standard firmware has all sorts of limitations. It does work, which is the best thing that can be said for it. There is a reason that there's all sorts of alternative firmwares though. I'd recommend Teacup, mostly because that's the one that I'm familiar with. It has been run successfully on gen3 hardware, but I can't remember by whom. You'd have to ask for lots of help getting it going, I'm sure. It would certainly address the segment pausing and max speed issues though!

---

--
I'm building it with Baling Wire

I have RAMPS but I don't have the time to switch to it yet.

Im using the monotronics. Any one have issues with it yet?

I havent begun printing yet because of a overheating motor issue melting my plastic, which I will purchase heatsinks for.

The motors shouldn't get hot enough to melt or soften the plastic. Have you adjusted the trim pots for the stepper controllers?

Yeah I adjusted them and they did get too hot. They got to 58C which was too hot to handle. I was told by Kurt from Techzone that he had to do that once too (in order to have enough torque) and had to add a heat sink to the motor to reduce the temp.

The motors I used were NEMA 17.

---

[omemon.wordpress.com]