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http://reprap.org/wiki/Laser_Cutter
Re: Extruder digging into object - 11 years ago
I suggest you follow the reprap calibration guide. It has just about everything you need to get your machine calibrated.by sheck626 - Reprappers
E3D hotend - thoughts? - 11 years ago
I just switched from a j-head over to an e3d all metal hotend, and I must say I have mixed opinions. It is a very well engineered hotend, but it does have some issues that I've seen. First off, the plastic fan adapter provided with the kit was completely useless. It was loose to the point where you could just slip it off and if you shook it, it rattled like crazy. The instructions warned to "by sheck626 - Reprappers
Re: can I use hook 2 power supplies in parallel? - 11 years ago
30A at 120V = 3600W, so I don't think you're going to need that much power! P=I*V (Power = Current x Voltage) so at 12V you do need 30A to acheive 360W, but you only need 3A from the 120V side (well a bit more to account for inefficiency in the PSU).by sheck626 - Reprappers
Re: can I use hook 2 power supplies in parallel? - 11 years ago
If your machine requires 13 amps and you connect two perfectly matched (highly unlikely) power supplies in parallel, then each one would deliver half the load (6.5A), so you've already over-loaded your 4 Amp power supply.by sheck626 - Reprappers
Re: extruder gets too hot after dropping a bolt (SMH) - 11 years ago
"M104" is the "gcode" command to set the extruder temperature. It looks like this: M104 S210 That means "set extruder temperature to 210C, but don't stop and wait for it". M109 S210 means "set extruder temperature to 210 and wait until it's stabalized at 210C". If you see something like M104 S200 or M109 S200 in your gcode, it's commanding the firmware to change the extruder temp to 200C.by sheck626 - Reprappers
Re: extruder gets too hot after dropping a bolt (SMH) - 11 years ago
It landed on one of the stepper drivers so it would have no effect on the temperature of the extruder. I'd look at the gcode and make sure there isn't an M104 commanding the extuder to 200. You might also check the PID tuning since it may just be overshooting the temp in the beginning. Does it show room temperature when it cools down? If so, then it's reading the thermistor properly. Does thby sheck626 - Reprappers
Re: Does a J-Head Really Need an Aluminium Groove Mount? - 11 years ago
Where do you find these "hot" ABS filaments? I'll admit, I've only printed Ultimachine filament, but I've never heard of anyone printing ABS above 240C. Certainly not 250-260. Does "hot" ABS require hotter HBP temperatures, or offer higher glass-transition temps? What is the advantage to using "hot" ABS filament? I'm in the process of converting to an E3D 1.75mm hotend, so I'd like to know iby sheck626 - Reprappers
Re: Printing ovals instead of circles! - 11 years ago
Could it be the pulley sliping on the motor shaft?by sheck626 - Reprappers
Re: By Jove I think I've sussed it. Sticking to the bed. - 11 years ago
Are you printing to a heated bed? If so the air flow due to the movement of the print bed may be causing parts of the bed to get too cold. Otherwise, I can't see why it would matter unless your Y steps/mm were out of calibration.by sheck626 - Reprappers
Re: Need help working out whats going wrong with this print - 11 years ago
You probably need to adjust your cooling settings in your slicing software to allow for longer layer times. Some objects need to be printed slooooooooow. I've printed ABS at 4mm/s without issue although I have my minimum speed set to 10mm/s now since it works for most objects. If you want a quick way to test if your layer time is the issue, then try printing several of the same object on the sby sheck626 - Reprappers
Re: Jhead conversion from 3mm to 1.75 - 11 years ago
>This is why the PEEK NEEDS to be cooled if printing in ABS. The PEEK does not need active cooling when printing ABS.by sheck626 - Reprappers
Re: Heatbed broken...? - 11 years ago
Definately a short. Also, why did the resistance of your heatbed increase after installing the LED+resistor? It should be connected electrically parallel to the printbed, so if anything the resistance should decrease. And why replace the entire RAMPS just because of a bad MOSFET? When you connected the light bulb in series with the printbed, and the light bulb was bright and the LED on the prby sheck626 - Reprappers
Re: 4 PLA Bushings (Mendel i2) - 11 years ago
The problem with saying you have an I2, or an I3, or whatever reprap you're building is that there are several different variants of it. No two people have the exact same machine. That said, on the standard I2 design, the bushings attach to the X carriage without the bushing clamps in photo 1 (those are for the printbed/Y axis). Also, the PLA bushings and the metal bushings are the same part.by sheck626 - Reprappers
Re: Measure your skirt with a caliper. - 11 years ago
The width of the skirt is dependant on the distance between the nozzle and the printbed, the feed rate, and the extruder flow rate, not the nozzle diameter. The nozzle diameter imposes a lower limit to the trace width (trace width can't be lower than nozzle diameter), but the width can certainly be wider than the nozzle's diameter. If you don't believe me, try moving your Z endstop and printingby sheck626 - Reprappers
Re: J-Head Hot End. Help? - 11 years ago
My first one I bought from an unknown source on ebay and it never failed me and I used it for several months after I built my printer. I still have it, I just don't use it because I have a newer j-head with a smaller oriface and a shorter barrel. YMMV.by sheck626 - Reprappers
Re: J-Head Hot End. Help? - 11 years ago
If you're just starting out, I'd go with an 0.5 or 0.4mm oriface. The smaller the oriface, the more it's prone to jamming up. Believe me, you do not want to deal with a nozzle jam when you're just learning how to calibrate everything.by sheck626 - Reprappers
Re: J-Head Hot End. Help? - 11 years ago
No, you don't need the heater cartridge, the included power resistor works just fine. I'd order it right from the source at hotends.com though.by sheck626 - Reprappers
Re: My axis wont move when I print!!! - 11 years ago
1) Your filament diameter needs to be accurately measured 2) Your layer height is a bit high for your nozzle diameter, try 0.3mm 3) Your hotend isn't heating and therefore the print never starts. The command "M109 S200" tells it to set the hotend temp and wait until it's reached before doing anything else, but since it isn't heating it never continues the print. Check the wiring for your hotby sheck626 - Reprappers
Re: Power supply question - 11 years ago
Personally, I'm using an old "broken" PC power supply because it was something I had lying around. If I had to buy one though, I'd get the one you linked to since it looks like it would work great. As far as safety is concerned, the machine you're building is probably more of a concern than the power supply.by sheck626 - Reprappers
Re: Heatbed MK2a - Can it run on 24V? - 11 years ago
If you're using Marlin, you can set BED_MAX_POWER in your configuration.h to something less than 256 (full power). I've never tried it before, but I think it would work just fine with 24v as long as you reduce BED_MAX_POWER to something reasonable. If, as Eddu mentioned, the mosfet can only handle 140W, then you'd have to set the BED_MAX_POWER to 70 which should give you an effective power dissby sheck626 - Reprappers
Re: PID settings in marlin, how important are they? - 11 years ago
>Marlin doesn't, IIRC, use PID for the heatbed since its response is much slower and temperature fluctuations less of a problem, so bang-bang control is sufficient. Marlin does support PID on the heatbed and I'd recommend using it (I do). It keeps artifacts caused by the varying expansion of the heatbed out of your prints.by sheck626 - Reprappers
Re: PID settings in marlin, how important are they? - 11 years ago
PID pulse-width modulates current to the hotend in order to keep it at a constant temperature (more or less). The other method simply applys current if the temp is too low and shuts if off if the temp is too high, the result being that the temperature is constantly either too low or too high. Since you have marlin firmware, PID configuration is easy! It can be done with a command such as "M303by sheck626 - Reprappers
Re: Bottom layer squashed - 11 years ago
Slic3r allows you to set the trace width for the first layer. By default it's set to 200% for the first layer for better adhesion, so you may have to change that if you want an even first layer. Also, in my experience, when printing to a heated surface the bottom layer always seems to be squashed, but when printing onto a non heated surface (PLA on blue painter tape for example) the bottom layeby sheck626 - Reprappers
Re: Prints Coming Out w/ Strands - 11 years ago
The print surface isn't flat/rigid like glass. Just buy a $2 picture frame at the dollar store and cut the glass with a cheap glass cutter from your local hardware store and you'll be back in business.by sheck626 - Reprappers
Re: power supply overload - 11 years ago
Does the extruder heat work with everything else turned off? The printbed uses signifigantly more power than the extruder, so if the printbed works by itself but the extruder doesn't, then there's a short.by sheck626 - Reprappers
Re: Alien Egg... - 11 years ago
That's pretty much why I don't like to do long unattended prints. I can imagine all kinds of failures that would end up much worse than what happened to you.by sheck626 - Reprappers
Re: Inaccurate Z steps? - 11 years ago
I have to constantly adjust my Z endstop as well. I don't know what it is, but it seems that before every print, I have to adjust it. It's much easier with an adjustable endstop though. I'm thinking maybe an optical endstop would be better.by sheck626 - Reprappers
Re: Mk2a PCB heatbed Woes - 11 years ago
A $30 multimeter should be accurate enough to measure the resistance in most cases. Although improving the insulation would help, in the end I think 80W simply isn't enough power to heat up the mass you're trying to heat up (and keep it hot when everything is moving). Using a higher voltage would work, but that would require another power supply which would probably cost more than just buying aby sheck626 - Reprappers
Re: Can't print moving parts 
- 11 years ago
The bottom layer is influenced by the print bed height (distance from nozzle). If your bed height is too low, it will look like you're under-extruding even if you're actually over extruding. Use openscad to generate a 50x50x50 cube, export it as STL and then slice it with one perimeter, no top or bottom solid layers, and no infill. Print out about 20 layers or so and then cancel the print, theby sheck626 - Reprappers
Re: Extruder Gear Grinding - 11 years ago
I've been using ABS gears for quite some time now with no signs of degredation. If I used an ABS small gear with a PLA large gear I would expect the small gear to wear out more quickly since PLA is more rigid than ABS. The only reason I'm using ABS is because I'm concerned that the heat from the extruder motor would soften/melt PLA. With ABS for both gears, I haven't had one wear out yet.by sheck626 - Reprappers