Viktor, While your 'old' technology works (and I do like it myself) its so horrendously inefficient its unbelievable, SMPS is much better, line volts insensitive to boot. J.by John W - Controllers
Have you followed this? J.by John W - Controllers
Does it have current sense lines you need to connect up? If the fan comes on it must be working. J.by John W - Controllers
Why do you think it is the powersupply? Are you using a PC ATX supply? I would be surprised if you could blow one up.... Try metering it just on the bench without anything connected. J.by John W - Controllers
Like Viktor says, you should be a square wave like the picture below Not a sine wave Assuming its the former your seeing rather than the latter it should be just about running, if you put a second probe on one of the coils it should be out of phase with the first if it is working properly. Try uploading the following code to your arduino and see if it runs better (change the pin assignmentby John W - Controllers
I was just musing to myself - is it better to use a stepper or a high torque DC brushless motor with an encoder in terms of precision? Instead of outputting PWM you receive it as an input, is backlash a problem this way? J.by John W - Controllers
kylecronan Wrote: ------------------------------------------------------- > The heat sinks on all of my motor controllers are > getting really hot, even when inactive (I guess > for holding torque?). Is this normal? I believe thats because you always sink the max current from the steppers when stationary because the single arduino config does not have enough free pin outs to control thby John W - Controllers
Hmm pricey (more than ball screws)... Near the bottom, but the concept is still there, you could ask supermagnets to deliver a unit which is one piece and suitable that has 1mm protrusions like a H to achieve the same effect, and reprap the gaps in the H with plastic. J.by John W - General
We have a few of these kicking about at work And a really large one on the big CNC machine (6'x4' at least) that can do 15mm cuts through plate steel with a 10mm cutter at high speed, with the magnet holding it in place easily. Cant see an online vendor for pricing though.... Building it out of a pair of electromagents is more rappable than a perm and electro really. J.by John W - General
That sounds like exactly the problem I had yesterday, issue one I had was my SMPS kept dropping the 12v line every second or two for a few milliseconds, fixed by switching to a proper bench supply. The second problem I had was I needed to tune speed pretty accurately to get good results - I did this using the code sample on the stepper driver page. As for an oscilloscope, the link below looks pby John W - Controllers
Is your answer here? Where you need to swap a coil over? My problem at the minute is the stepper exerciser works in reprap on snap 1.3, but when I load a stl and try and build using the host software the steppers dont do anything at all J.by John W - Controllers
The boards already have the resetb thing enable with a capacitor and transistor arrangement (by the looks of it). I have got some newer 530 based boards which have both directions fully enabled now, I had to hack the cw/ccw bit on the 540 boards as in thier proper application they only rotate ccw. I'll try uploading the gcode firmware tonight as I can just send that gcode down the serial port.by John W - Controllers
Ah, but if I upload the gcode firmware rather than reprap it would appear you can simply send it gcode down the serial port - which is easy Which is what I will try out tonight J.by John W - Controllers
Hmm, I deleted everything and re-installed it all and now its working proper. Can I use the 1.3 to do the stepper motor debugging without the rerap software or do I need to fire that up? J.by John W - Controllers
Hi, I have another quick question - I am using my own driver boards which I already have lots of (and paired motors), I know they work when you bit bang them from the parallel port but I couldnt seem to get it working quite right from Arduino, using the code that is below It only works in one direction from the re-rap PC software, using that code with some small amendments (changing delayMicrby John W - Controllers
o: In function `__static_initialization_and_destruction_0': undefined reference to `ThermoplastExtruder::ThermoplastExtruder(unsigned char, unsigned char, unsigned char, unsigned char, unsigned char, unsigned char, unsigned char)'Couldn't determine program size: C:\Program Files\arduino-0011\hardware/tools/avr/bin/avr-size: 'C:\Documents and Settings\John\My Documents\reprap-arduino-firmware-1.3\by John W - Controllers
Well I had never even installed any previous versions - only 1.3 and it didnt compile - I dl 1.2 and it compiled and went straight on without problems. Will try 1.3 again, perhaps later tonight - need to find the 24v powersupply I have to breath some life into the steppers... J.by John W - Controllers
Ok thats got the RXTX lights flashing on Arduino when I set the port to COM3, and the exerciser routine opens now - the comms test still does nothing though. Still progress. J.by John W - Controllers
Ok I'm installing the RXTX bits now - pre-compiled version is Quite old don't know if it'll work yet or not. J.by John W - Controllers
Well the Arduino arrived from cool components today, got the Single_Arduino_SNAP.pde v1.2 uploaded fine, v1.3 doesn't compile on my machine. Then I closed the Arduino software and opened the reprap host but I'm not sure its connecting - I presume it still works over the usb lead/serial host. Which on my XP laptop is COM3. The basic comms test doesn't seem to do anything, and there doesn't seeby John W - Controllers
I retitled the thread to something more useful. J.by John W - General
I have virtually unlimited access to steppers and driver boards suitable for the task (albeit 24v), which may alter my design somewhat from the cheapest. Although the old adage 'good enough is best' still rings true. Attaching the stepper to the bed and having static screws makes things a whole lot simpler though thats what I am going to do I think. Back to BnQ today I reckon for some more bitby John W - General
I am about to start building (already have a working cnc pcb driller) I really liked the elegance of arnie, as in this pic where the vertical members are also the table bearings, which I understand is not without near perfect alignment idiosyncrasies. Then the blog shows that direction was moved towards the current darwin design using 4 sets of studding as lead screws, which again seems oveby John W - General
Thermocouple is significantly more robust and significantly more accurate - I believe its a case of either or... J.by John W - General