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Rostock, Kossel, Simpson, 3DR, and more. See: http://reprap.org/wiki/Category:Delta. Previously named "Delta Robots and Stewart Platform"
Re: Heated Bed ideas? - 10 years ago
You could place a couple fans along side the bed and turn them on after a print has finished using custom gcode. That should speed the cooling of the bed. If you go with aluminum, definitely get cast tooling plate. Extruded plate is not flat enough in the size you're talking about. If your bed moves in the Y axis you'll have a high moving mass which will require a more powerful motor if you wby the_digital_dentist - Mechanics
Re: Belts constantly slipping: correct tension? - 10 years ago
Sometimes the motor will slip but it will sound like the belt is slipping. You can check that by making a mark on the drive pulley with a marker or a piece of tape. When the noise occurs is the pulley actually turning or is it stuttering without turning because the motor is slipping? If the motor is slipping, check the current, speed, and acceleration settings. Make sure the grub screw on theby the_digital_dentist - Printing
Re: Keeping print bed level (melamine bed) - 10 years ago
If the problem is at the bed and not the X axis, it's probably a structural problem, not the material from which the bed is made. A lot of printers are relatively flexible and after you apply some effort to remove a well-attached print the bed ends up in a different position than it was before, requiring releveling/zeroing. The cure for that is either beef up the structure so it doesn't happenby the_digital_dentist - Printing
Re: Aluminium Heat Bed - 10 years ago
I have a 1/4" x 12" x 12.5" cast aluminum tooling plate bed with a 450 W kapton heater powered by a 24V transformer with AC power switched by an SSR. I turned the max PID frequency in smothieware down from 20Hz to 8 Hz. The thermistor is screwed to the bed. There is currently no insulation on the bottom side of the bed, except for a small piece of silicone foam that is covering the thermistor,by the_digital_dentist - Reprappers
Re: Aluminium Heat Bed - 10 years ago
Your scope photo is impressive, but the avalanche is over in under 250ns and the ringing voltage has dropped below 20Vpk in under 1 us. The FETs in the RAMPS board are rated for 50A continuous and the SOA curve shows that they can handle >100A for 100 us (that's 400x the duration of the avalanche in your scope image). I don't think avalanche is going to be an issue. Marlin PID operates at aby the_digital_dentist - Reprappers
Re: Acetone Vapor Finishing Device - 10 years ago
Acetone boils at about 56C. That Peltier junction device is like any other semiconductor - you'll have to be very careful to ensure you can dissipate the heat it produces or you'll kill it very quickly. Your idea seems overly complicated to me. Acetone isn't expensive or toxic enough to bother with vapor recovery. I think a real problem to be solved is circulating the vapor so it treats theby the_digital_dentist - General
Re: Mig 4-roller extruder? - 10 years ago
I think at 50 or 60:1 it's going to have a very low maximum printing speed, especially if you're using 1.75mm filament.by the_digital_dentist - Mechanics
Re: Keeping print bed level (melamine bed) - 10 years ago
Checking alignment or axes is best done printing a rectangular solid. A rectangular solid will have two diagonals in each plane. You can check all three axes for orthogonality by measuring diagonals in the XY, YZ, and XZ planes. Leveling the bed does not compensate for axes that are not orthogonal. It only lets the first layer stick to the bed. If the axes are not orthogonal circles won't beby the_digital_dentist - Printing
Re: Aluminium Heat Bed - 10 years ago
Running a 12V heater from a 24V supply will dissipate 4X the power at 100% duty cycle (maximum PID duty cycle setting of 255). If you set the duty cycle to 25% by using a maximum setting of 63 you'll get the equivalent power dissipation of a 12V supply. Since it is taking too long to heat at 12V, you can set the maximum duty cycle to maybe 70 or 75 to increase the average power to the bed. PIDby the_digital_dentist - Reprappers
Re: Aluminium Heat Bed - 10 years ago
I think he means to get a big 24V supply to power the bed and then a smaller 24VDC- 12VDC converter to power the controller and motors.by the_digital_dentist - Reprappers
Re: Keeping print bed level (melamine bed) - 10 years ago
Check the couplers that connect the Z axis screws to the motors. If one or both are slipping the Z axis will never behave properly. Make sure the motors have adequate current.by the_digital_dentist - Printing
Re: Aluminium Heat Bed - 10 years ago
If the controller runs on Marlin or Smoothieware (and probably others), PID control is an option that should be turned on. Bang-bang control allows relatively large swings in the bed temperature that will cause artifacts in the Z axis of the print.by the_digital_dentist - Reprappers
Re: Best material to reduce those pesky vibrations - 10 years ago
I'm not entirely sure. When I switched to the DSP driver + 32V supply on the belt driven X axis it became weirdly quiet, so I guess the answer is yes. I never operated the Y axis motor without the DSP driver so I don't know how it would behave with a chopper driver- the pololu drivers I have can't handle the current that the motor needs. I did some earlier tests on the Y axis screw drive withby the_digital_dentist - General
Re: Keeping print bed level (melamine bed) - 10 years ago
Have you checked the Z axis? Maybe the screws are getting out of sync due to binding, slipping, etc.by the_digital_dentist - Printing
Re: Aluminium Heat Bed - 10 years ago
Increasing the voltage should get it to heat up faster, but be careful if the power supply is near its current limit. If it's good for 20A at 12V it will only be good for 17A (or less) at 14V. If you exceed the designed power limit it will die quickly. In my experience, if the power supply's cooling fan turns on, you had better turn the voltage back down because the supply won't last long if iby the_digital_dentist - Reprappers
Re: print quality issues - 10 years ago
If you haven't calibrated the machine you will naturally have all sorts of printing problems and they will continue until you calibrate the machine. Calibration includes adjusting motor currents, setting maximum speeds and accelerations, steps/mm for all axes and the extruder, running PID autotune for the bed and hot-end, limit switch functions, bed leveling and zeroing, etc. You may find thatby the_digital_dentist - Reprappers
Re: Holes at sharp turns and angles - 10 years ago
Check this site for an explanation of how to tweak the settings for optimal infill: richrap.blogspot.com/2015/01/slic3r-advanced-perimeter-tuning-3d.htmlby the_digital_dentist - Printing
Re: Temporary Support Structures - 10 years ago
They are usually only lightly attached (you can tweak parameters for that) so that the support material breaks off easily.by the_digital_dentist - General
Re: Temporary Support Structures - 10 years ago
Cura and slic3r will both generate support structures automatically.by the_digital_dentist - General
Re: I think I figured out how to make a self replicating robot! - 10 years ago
I suggest you patent the idea before someone beats you to it...by the_digital_dentist - General
Re: Belt Clamps - Ord Bot Hadron - 10 years ago
Try this: It uses the belt's own teeth to prevent any slip. Even if the the center post were to break loose, the belt won't slip.by the_digital_dentist - Mechanics
Re: print quality issues - 10 years ago
Here's what I'd do in your situation. First, I'd make sure all the mechanical relationships in the machine were right. That means making sure the frame is bolted tightly together, belts are tight, moving parts are moving freely throughout their allowed ranges, pulleys are firmly attached to motor shafts, etc. Next I'd check the wiring and make sure everything is connected properly with adequaby the_digital_dentist - Reprappers
Re: Guide rails and other questions - 10 years ago
You're kind of building your machine backwards. Normally you decide what the machine should do, then you figure out the mechanical stuff required to make it do that, finally you select the electronics. I'm not sure why you think you need NEMA-23 motors (why not NEMA-34?) or why you think that a smoothieboard can't drive a NEMA-23 motor (it will drive any size stepper up to 2A). You have a loby the_digital_dentist - Reprappers
Re: I think I figured out how to make a self replicating robot! - 10 years ago
Are you suggesting that the hardest part of making a self-replicating machine is copying data from a memory stick? I think you need to spend more time thinking about the whole project. You are clearly misunderstanding the function of a RepRap printer. These machines don't replicate themselves. That is a philosophical concept within the RepRap project/community, not a reality. RepRap machinesby the_digital_dentist - General
Re: Bulldog XL + E3D v6 - 10 years ago
I have the BullDog XL and E3D v6 combo. I did not buy an extra $30 foot for the BullDog XL and I left the plastic Bowden tube adapter in the top of the hot-end because it holds the teflon tube in place. Since you have the extra foot presumably made to marry these together, you probably don't need to do any of what I did: 1) file a notch in the heatsink fins on the hot end to allow easy accessby the_digital_dentist - General
Re: How to chose a linear slide system? - 10 years ago
I recently converted my printer from 1/2" round guide rails to fully supported linear guides and found that the friction and precision are both higher. In general, even small linear guides are spec'd for much heavier duty use than we subject them to in a 3D printer, so they should last a very long time. The increased friction means you may need more current or higher torque motors to push them aby the_digital_dentist - Mechanics
Re: Best material to reduce those pesky vibrations - 10 years ago
OK, you got things moving fast. That's what all the cnc guys posting youtube videos of the dampers did. I don't think it reflects the realistic situation of printing where you have to start, stop, and reverse direction rapidly. What's the print quality like? I suspect that by increasing the moving mass (about 200g for the smaller flywheel) your ability to start and stop the motion has diminisby the_digital_dentist - General
Re: Questions about Z axis drive - 10 years ago
The main thing you need to worry about with 3600 steps/mm is the maximum speed you try to move the Z axis- can the controller send pulses fast enough to move the axis as fast as you're telling it to go? If you're using Arduino/RAMPS, the max step rate is 40k/sec. 40k/3600=11.11 mm/sec maximum travel in the z-axis. That should be faster then you ever need it to go. OTOH, since it sounds like tby the_digital_dentist - Mechanics
Re: Weird distortions internal holes - 10 years ago
Have you calibrated the X and Y axes and made sure they are orthogonal? Have you measured the outer diameter of the gear at different points to check for roundness?by the_digital_dentist - Reprappers
Re: Best material to reduce those pesky vibrations - 10 years ago
So this is a flywheel? What is the mass?by the_digital_dentist - General