Rambo Expansion?

Hey everyone, I’m looking into (very early stages right now) doing some odd expansions for the Rambo board. I notice there’s a PWM Expansion section, and a Motor Expansion area on the Rambo (still trying to find a bit more info on those). It looks like some of the pins in those sections are shared with other things (I see a Fan on the PWM extension in the schematic).

Does anyone have an Eagle schematic/brd file for the Rambo? Does the TAZ4 Use Rambo 1.1, 1.2, or 1.3?

Essentially, right now I need to find a PWM pin for a servo, and further down the line I may attempt to add a 3rd (and possibly 4th!) extruder motor, hotend, and thermistor. I’m very comfortable soldering, designing PCBs, etc, but I know very little about the Rambo itself, so any tips would be appreciated!

Did you try googling “Rambo controller” to find this: http://reprap.org/wiki/Rambo

I looked into this prior to ordering my Taz5. It would seem that there are a few PWM availabilites on the board. IIRC Pin 3 on PWMExtra (dont hold me to that) was one. I believe there is a header installed already on the board. I will be adding a 5w laser to mine as soon as it is available.

Yeah, I found the eagle schematic and board file for the latest Rambo board (not sure what my Taz 4 uses) on github - I don’t have the link on hand at the moment but I’ll try and post it in later tonight.

It looks like the PWM expansion has two free PWM pins, and another PWM pin that’s shared with the electronics/case fan (so probably not that useful) and GND and Voltage pins. The Motor Extension has a few more PWM pins on it, along with ground, voltage, etc.

Anyone know if those Gnd and Voltage pins are logic level (5v? 3.3v?) or are they 24v for some insane reason?

Right, here’s that board and schematic file: https://github.com/ultimachine/RAMBo/tree/master/board

Slightly annoying, you can’t just alt-click the link to rambo.sch or .brd, as it’ll actually download as an HTML file (with the .sch or .brd extension!) and Eagle will complain. Took me a while to figure that one out, silly Github.

Here’s a zip you can download: https://github.com/ultimachine/RAMBo/archive/master.zip

Thanks, Orias!

One thing I’m noticing is that the RAMBo 1.1 seems to have a different pin arrangement for the Motor Ext - after 1.2 the whole section is rotated 90 degrees. So it looks like I’d need to make at least two versions of this board - one for pre 1.2, and one for post 1.2.

Though at first I will likely just make one for anything after 1.2, and if there’s enough demand for a 1.1 version then I’ll put that together.

I don’t think you’ll find enough interest to justify manufacturing and expansion add-on to RAMBo. Last year about this time a number of guys started down this path to support the Kraken hot end (4 nozzles). Then Azteeg released the very nice X3 Pro that supports 8 steppers, up to 5 extruders with too the hotend, a heated bed. It has 8 MosFETs, 6 thermistor inputs, w thermocouple inputs and if that isn’t enough, the darned thing is expandable too. That pretty much shut down the RAMBo efforts. All this for $135.

Sure - But I (and many others, especially here on these forums) already have and are accustomed to the RAMBo. I’m not looking to make a ton of money on this (and honestly haven’t decided if I’ll even do it).

More options are always better. From my own consumer standpoint, I’d feel much more comfortable plugging in an expansion board and running a firmware update compared to totally swapping out my current control board, reconnecting everything, making sure it all works and I’m not going to fry anything, etc. I also wouldn’t have a ‘scrap’ 3d printer control board laying around (the now-unused RAMBo).

Plus, that Azteeg board won’t fit in my nice little lulzbot machined electronics enclosure with the nice fan and everything :stuck_out_tongue:

Oh and that Azteeg board also (similar to mine) requires you to buy and socket a whole bunch of Polulu stepper drivers. From their site, that means you add another $64 to that $135 just to buy 8 stepper drivers - when the RAMBo you’d be expanding already has 5 of them on-board.

Edit: and no heatsinks on those drivers! More little costs that add up.

Second edit: AND, far as I can tell (haven’t looked TOO deeply into it) I’d need a new LCD panel for the Azteeg as well - it’s not readily apparent that anything other than the Viki LCD works with the Azteeg. So that’s another $75 to get a new LCD screen.

True, but you buy what you need. And the drivers are 32 micro stepping.

Anyway, I just wanted to give you a heads up in case you were unaware. I’m converting all my printers to smoothie. Now, there is where an expansion board would be nice and there is not competition.