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Re: Project: Teacup Firmware - 12 years ago
Should the example BANG_BANG_OFF in the config files be smaller than the if(value >= 8) test in heater.c/heater_set() routine? I've finally gotten around to getting a heater working on the $16 teensy 2.0 breadboard, after several missteps. I think the config.h #define BANG_BANG_OFF 45 might have led to part of my confusion, but my burning out the DIO5 pin didn't help with my confusion at allby DaveX - Firmware - experimental, borrowed, and future
Re: Serial or Parallel for the Z motors - 12 years ago
I wired mine serial on Z, but I'm a rank noob, so feel free to discount it. I had burned up a motor on my Y axis while fiddling with setting the currents, and then thought hard about it while awaiting a spare. I couldn't find significant downsides. Serial seems safer, less amps, cooler for the Pololus, etc..by DaveX - General
Re: Hotend theory - 12 years ago
How did you destroy your hot end? How tight is your temperature transition zone? Some thin the metal so that they can control the location of the cool end of the melt zone. How does your hotend deal with the issues discussed in ?by DaveX - General
Re: Printbed size: what do you actually use? - 12 years ago
Even if you don't print to the full 200x200 size of the HBP, the heated margin surrounding smaller prints might be preventing warping at the edges and corners.by DaveX - General
Re: Project: Teacup Firmware - 12 years ago
Dave X Wrote: ------------------------------------------------------- > 3) 57600 seems too fast for Teensy: > -- I got > garbled M115 results at 57600 baud. One can bypass lufa_serial and use the usb_serial_* routines from Teensy at and seems to get full speed USB communication. Pronterface at 250000 baud talks reliably to my modified Teacup on my Teensy's 16MHz ATMEGA32U4. ...stby DaveX - Firmware - experimental, borrowed, and future
Re: wildeye's simple hotend - 12 years ago
That Wildseyed's duck(Kapton)-taped solution works with some degree of reliability opens the doors to all sorts of improvements. I've staked the tip into the heater block with a bumps from a scratch awl. I like the tape just fine fine. If you are picky about neatness, you could do a more careful job of taping, but the Kapton taping is adequate and enables testing variations, like a block with aby DaveX - Plastic Extruder Working Group
Re: How to calibrate Pololu A4983 drivers - 12 years ago
With Pololus, the sensing resistors are Rs=0.05 ohm, and per the A4988 datasheet, the calculation for the maximum trip current I_TripMax= Vref/(8*Rs), so Vref of 0.4 should produce a maximum current of 0.4/(8*0.05)=1A I'm aiming for max 0.7A on my 1A rated steppers, so I rearrange it as: Vref = I_TripMax * 8 * Rs or Vref = 0.7 * 8 * 0.05 = 0.280V With a measured Vref of 0.273V, I should exby DaveX - RAMPS Electronics
Re: Weird pulsing Issue with RAMPS 1.4 - pots on motor drivers are turned all of the way down and heat sink stays cool - 12 years ago
If the Pololus are cool to the touch, then the over-temperature protection isn't causing the pulsing. The LEDs blinking in sync with the pulsing sounds like power cutting out to me. Maybe try a different supply?by DaveX - RAMPS Electronics
Re: two steppers on one axis - 12 years ago
It looks folks like wiring paired steppers up in parallel rather than series. It seems like if someone was using a current limiting driver like a Pololu, you should wire the motors in series, so that if you open circuited one stepper's coil, the other wouldn't get double the current.by DaveX - RAMPS Electronics
Re: Newbie questions - 12 years ago
It looks like might be a bit wimpy and take larger steps than the 13.7 N-cm torque, 1.8 degree standards on The plotter might be stronger. The stepper driver boards should drive these OK for learning the interfacing.by DaveX - General
Re: Building a reprap incrementally - 12 years ago
Splated Wrote: ------------------------------------------------------- > I want to do the same thing, but I have access to > some dead laser printers at work, and I'm pulling > the steppers from them. I'm just not sure what to > get controller wise, I don't want to risk burning > out my Arduino. > Many of the RepRap boards, (RAMPS, Sanguinololu, and the other ) use the Pololby DaveX - General
Re: Building a reprap incrementally - 12 years ago
It's pretty much the same as my plan. About a month ago I first read about RepRap. I had a Teensy microcontroller and a couple thrift-shop scanner steppers laying around, so I half-baked ported Teacup to the Teensy, then spent about $50 on a couple Pololu driver boards and a beefy NEMA17 stepper to see some motion. Then I was headed down the slippery slope. I saw that Wallace would work withby DaveX - General
Re: calibrating extruder stepper current - 12 years ago
There was a difference of opinion about whether you should set it high enough for stripping the filament or low enough to skip steps atby DaveX - General
Re: Hotend theory - 12 years ago
Hobbes20xx Wrote: > @wildseye, drilling a concentric hole in anything > is hard for me with only a drill press, im not > sure i can manage through that ptfe If you put the stock rather than the drill into the chuck, concentricity is enforced by the spinning of the stock. Mis-positioning the drill bit would affect the size and uniformity of the bored diameter as the bit flexes towardby DaveX - General