Thanks for the thumbs-up Bob. I don't remember reading that did-bit anywhere. It's starting to come together in my head. Still a long way off from a pretty print but it's starting to look better. Regards! Rossby rossfree - Reprappers
Thanks Misan... I suspected as much. And I agree Brian, it's probably not much error to worry about. Still... I think homing before print and staying energized through print to keep track of steps would be my preference. Turning off after print sound fine. Regards, Rossby rossfree - Reprappers
In the shower today I had an epiphany! (That's where I do all my best thinking.) All those settings in Sfact (Skeinforge) are for building the gcode file for building the part. Once the gcode file is made, changing those settings only affects the next stl file that I pull in. Is this correct??? Put another way... if I have a gcode file of a part and change settings in Sfact, it does not changeby rossfree - Reprappers
Thanks all, I was pulling my hair out looking for the "switch". With all that's in there, I am surprised that there isn't something simple to scale everything without having to convert it. But then... I didn't lift a finger to write the code. :-) I'll find the mm switch and re-save the stl files in mm. (now i've got to find THAT switch) **bother** :-) Rossby rossfree - Reprappers
Hi all, I'm trying to print some stl files I created at work. When I pull them into Pronterface, they look really really small. I assume they are comming in as metric conversions. How do I change the settings so that they come in as inch conversions? I have been looking but don't know where (Sfact???) Stuck and needing an answer. Thank you! Rossby rossfree - Reprappers
...as am I! Congrats foshon! I'm currently trying to de-blob my first prints (sae prussa mendle). Having fun! Rossby rossfree - Reprappers
Rule of thumb... never rely on friction for anything except rug burns. Microstepping is an in-between step. If you are between steps and turned off the motor, it would cog back to it's closest step. Designers of stepper control boards often build in current reduction when steppers are stationary. This accomplishes exactly what you are referring to without undue heating. I do not know if this is dby rossfree - Reprappers
HI Arnold, Stepper motors do get pretty warm. Even hot to the touch under a lot of use and load. But you can calm things down a bit by backing off of the current to them. If you have the pololu stepper boards, there is a pot on the board that allows you to adjust the current to the steppers. Rule of thumb, if you can put your hand on the motor but have to remove it, it's hot but not too hot. Iby rossfree - Reprappers
Thank you Bryan, I'll try that! Rossby rossfree - Reprappers
Thank you Mlagana, That was a great link. I'm all over it! Is there a link like that for Pronterface? Thank you, Rossby rossfree - Reprappers
So I have something that looks like a Prusa Mendle. And when I push print... by golly, my print head moves around and spits snot all over the table. It doesn't look like anything yet but "she's givin it all she's got Captain!" I have Teacup, Pronterface and Sfact and loaded it all following the Youtube video... (I'll insert the credit and source here later). My head is buzzing from all of the sby rossfree - Reprappers
Quick update: It turned out to be the power supply after all. I thought it was large enough. Nope... 12volts at 12amps max. Not enough. I changed power supplies to one with 18 amps and the problem went away. First print this morning... a BLOB! Yeah baby! rossby rossfree - General
I'll be wiring the end-stops tonight and try another USB cable with ferrite. I never thought to switch to the USB supply... will do that as well. Then we'll see. Power supply if I get desperate. Tonight may be THE NIGHT! Whoot woot woot!!! Thank you Bryan! Rossby rossfree - General
Hi Pinaise, I agree... they really aren't expensive... and when the power is off, with the threaded rods, the Z-axis shouldn't move. Not so sure with spur gears and pulleys. Check out the video below... what a way to build machines... with everyone at the same time. Two day build! Awesome! Prusa Mendle Group Build Good luck! Rossby rossfree - Reprappers
By gear, do you mean timming pulley? Have a look at the Prusa-Mendle. The Z-axis threaded shafts are driven directly on each side by stepper motors wired in series. Simple and it just plain works. So much easier with fewer parts than the original Mendle. Regards! Rossby rossfree - Reprappers
Hi Misan, I'll be wiring in the endstops tonight. Still figuring how to mount them. :-) Rossby rossfree - Reprappers
Certainly that can be done! But it might add more components than you want to fool with. You have to have two belts, one for each side, a set of gears for reduction, two driven pulleys connected with a shaft (or two stepper motors with two sets of gears), Two idler pulleys to keep the belts tight. I don't know... the threaded shaft gives you great gear reduction and is pretty simple... copied oby rossfree - Reprappers
HI Misan, The power LED indicator comes on when the power supply turns on (out of standby mode). Power from the supply drives the LED. I'm leaning towards noise generated by the stepper motors. I think noise is interfering with USB communications and sending the control software to "yaya" land. I am going to try powering the AVR from the USB cable and using a different USB cable with a ferriteby rossfree - Reprappers
Thank you for your reply Misan, I am using Gen7 electronics. The computer power supply is turned on and off as needed in software. The power supply always provides a small current 5 volt supply for the processor but the main supply is turned off and on. There are two led's on board that indicate the small current 5 volt supply and the main supply when it is on. When I turn on the power supply (by rossfree - Reprappers
misan Wrote: ------------------------------------------------------- > i did have some problems with my electronics > (RAMPS-based). My problem was that USB would get > disconnected because of EMI interference, mostly > when a motor or extruder hot-end would be started. > The error code you get suggests there is a > communication problem once the print tries to > start but noby rossfree - Reprappers
Back at you... I'm typing on a different computer... don't have the host computer in front of me... but I think it was SFACT that I installed. I don't remember. My brain is jelly. I've spent the weekend on this. Whew! So... All the motors are wired up and jogging them moves them all in the right direction. That's good. I'm using fairly small steppers but they are surprisingly strong. Very happyby rossfree - General
Got it going Bryan!!! Thank you! Now I'm trying to get skeinforge running so I can run a dry test with an stl file. Having a bit of trouble figuring out where to put it. Sure is nice to see thing moving! Thank you! Rossby rossfree - General
Hi all, Update: I've built the prusa, the electronics board, and have loaded my firmware. Now I'm wading through the software choices. Exhausting! I wish someone would just point and say, load that, that, that and this. Now push go! Thanks for the suggestions Tiny. So far, I'm doing pretty good. I've turned a few parts to make the extruder. It's likely that I will have to play with it to get itby rossfree - General Mendel Topics
Thanks your your help folks, I purchased a new atmega 644 and a Pololu USB AVR Programmer. I was able to get it working and loaded the fuses, boot loader and firmware. Now I am wading through the process of determining the right software to run things. You know... I'm a dang good mechanical designer, a good electronics tinkerer, and I can build most anything... but my brain is in constant overlby rossfree - General
Thank you for the responses! It has been a weekend of frustration... I currently have only one (of three) computers to program with. Once computer is dead with a suspected bad motherboard, the other has no parallel port (bother). So I'm stuck with the one. I saw the boot loader hex files for the different chips and speeds... just didn't get that far. Trying to set the fuses first. I think, in tby rossfree - General
Hi all, I'm just stuck. I've spent the majority of two days trying to get a parallel port talking to the Atmega644 to set fuses and load the boot loader. I don't know what else to do. There are so many places this problem could be... my XP computer's parallel port, a possible mistake on my gen 7 board, the cable I made, a typo at the dos prompt... etc. It relentlessly gives the message: AVR deby rossfree - General
Thank you James! I'm not very west... bout as east as you can go. About ten miles north of Portsmouth, NH. Wish you were closer! I got the gen 7 v1.3 board etched, drilled and partially populated with parts I had in stock. I've made a list on digikey of parts I need but haven't yet pressed the button. The Atmega chip is holding me back. I don't have a bootloader board so I'm looking at bit bangby rossfree - General Mendel Topics
HI all. This is my first post. I'm a design engineer by trade working with Autodesk Inventor and a Dimension printer in-house. Love our printer but they frown on personal projects as the stuff is pretty expensive at about seven dollars a cu in. So I'm building my own! Plastic parts are being printed (on the Dimension) as I type this. The rods and hardware are in and I should have the board etchby rossfree - General Mendel Topics