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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: help needed timing a clock - 10 years ago
A clock is only as accurate as the reference. Are you using a crystal to drive the clock in the uC? Or an internal oscillator? Or is it tied to the power line for reference? If the uC clock is off, the errors will accumulate and your clock won't keep correct time. If the uC clock frequency drifts with temperature changes you won't be able to keep accurate time. The power line 50 or 60 Hz isby the_digital_dentist - Let's design something! (I've got an idea ...)
Re: Manual mechanical levelling of build platform - 10 years ago
Flatness can easily be checked the old-school way- use the edge of a steel ruler. If the surface is wavy and you can get a piece of paper between the ruler and the surface anywhere, the surface isn't flat enough, though with such a large bed you're probably planning on printing with thicker layers so more deviation from flat can be tolerated. If the surface flexes depending on temperature and aby the_digital_dentist - General
Re: What 3D printer design should I pick? - 10 years ago
If you build a solid design/rigid frame you won't need auto-leveling. Get some 8020 at your local scrap yard/metal recycler for the frame and while you're there keep your eyes open for linear motion components. The frame for my machine is all scrap 8020 type stuff (3 different makers/sizes, all about 1.5" square) and cost a total of about $80 ($2 per lb from the scrap yard). The pieces are allby the_digital_dentist - General
Re: Manual mechanical levelling of build platform - 10 years ago
Use a single motor and 3 or 4 screws all belted together. Using multiple motors is asking for endless hours of bed releveling. If you can live without a glossy smooth bottom surface on your prints, you can skip the bed heater and power supply and cabling and most of the leveling/releveling nonsense and just print on PIR foam. You'll be printing on rafts and for the first layer just bury theby the_digital_dentist - General
Re: Arctic Freeze water cooled hot end - 10 years ago
Adding pumps, hoses, reservoirs, heat exchangers, etc., adds a lot of cost/complication that would have to justify itself in terms of performance. What advantage does water cooling offer over air cooling?by the_digital_dentist - Plastic Extruder Working Group
Re: Deformed circle issue - 10 years ago
Are the axes orthogonal? If not you'll never print a round circle or a square square. Print a rectangular solid and measure the diagonals in each plane. If the axes of that plane are orthogonal the diagonals will have the same length. If they aren't, you need to tweak the position of the end of one or the other axis. You can download a spreadsheet here: It will tell you the error based onby the_digital_dentist - Printing
Re: Please help with Sintron Prusa i3... stuck at the commissioning stage. - 10 years ago
Work through one issue at a time. When a stepper makes no noise and doesn't move, you're either not sending it any signals or you've got it wired incorrectly. If it makes noise but doesn't move (like your Z axis motor), you probably have connections to one of the motor's coils reversed. Start with the X axis. First, push the extruder carriage to the middle of the X axis. If the motor doesn't tby the_digital_dentist - Reprappers
Re: Odd temperature readings - 10 years ago
Bad solder connections will do this sort of thing. The ground pins in particular can be a problem because they connect to a ground plane on the PCB and it sucks heat away from the soldering iron/solder, making it difficult to get a good connection. Check the soldering at the of the thermistor input pins on the controller board. You need a very hot soldering iron with a relatively large tip toby the_digital_dentist - Printing
Re: Anybody tried these closed self lubricating bearings with teflon - 10 years ago
Measure the diameters of the guide rails- I've heard stories of 8mm guide rails from China being not quite 8mm. That may be why the Igus bearings were sloppy and may be why the teflon bearings will be also.by the_digital_dentist - Reprappers
Re: Bulldog XL settings on prusa i3 was direct drive now 5 to 1 - 10 years ago
You save them to EEPROM and they will override whatever is in config.h. I prefer to modify config.h with the final values because that way the machine behaves according to the config.h file and you won't run into mysterious behavior 6 months from now when you forget that you stored constants in EEPROM.by the_digital_dentist - Printing
Re: Anybody tried these closed self lubricating bearings with teflon - 10 years ago
Make sure the rails are smooth as glass. If there's any surface irregularity on the guide rails it will chew up the teflon.by the_digital_dentist - Reprappers
Re: Dual motor on single extruder without compromise - 10 years ago
The the phase change that occurs when the filament melts takes heat out of the block, so what is needed is a higher powered heater that can put heat back into the block faster. The reason the temperature drops is that even though the PID controller is trying its best to regulate the temperature, it has already turned the under powered heater on full blast and still can't keep up. A higher powerby the_digital_dentist - General
Re: Dual motor on single extruder without compromise - 10 years ago
Here's another one I worked on and may yet revisit. It produced a LOT of down force but was geared so far down that it would probably limit printing speed: and here: It did not retract well. I have some ideas to fix that, so may go back to it soon...by the_digital_dentist - General
Re: Dual motor on single extruder without compromise - 10 years ago
It might be OK in Bowden setup. I think the key to getting a lot of down force from the extruder is very heavy tension on the pinch wheel springs and having a gear reduced motor for increased torque helps, too. I am currently using a BullDog XL extruder and it seems very strong. I haven't had any extruder jams in the couple months I've used it. If you put the motors so they face each other yoby the_digital_dentist - General
Re: Motor only turns with full stepping - 10 years ago
Turn the pot to mid position and try again. You may think it is at min current but maybe it's actually set to max. If it is truly at minimum current position and the driver is overheating, and you haven't shorted the motor leads, the driver is probably dead.by the_digital_dentist - Reprappers
Re: Dual motor on single extruder without compromise - 10 years ago
Here's a dual drive extruder I played with about a year ago: here's an earlier version: Both worked OK, but the second motor adds to the moving mass. I don't think it was any more reliable than a single motor extruder so I abandoned both designs.by the_digital_dentist - General
Re: Z Speed Limit - 10 years ago
If you are using Marlin, in config.h, the default_max_feedrate limits the maximum speed in all axes. homing_feedrate sets speed in all axes when sending the extruder home (which should probably be set below the default_max_feedrate settings).by the_digital_dentist - Printing
Re: Small parts with eyelets won't print. - 10 years ago
The problem is the small area of the layers. They don't have time to cool before the nozzle comes around and lays down the next layer of plastic on the still soft previous layer. You need to give it time to cool before printing the next layer. In Cura you can tell the slicer the minimum time per layer and if the layer finishes faster, it will move the nozzle away and wait, then resume the nextby the_digital_dentist - Printing
Re: Motor only turns with full stepping - 10 years ago
Check speed, acceleration, and jerk settings- set all low to start. Set the current control pot about mid turn to start- if the thing is overheating you probably have the current set to max, not min. Check wires and make sure you haven't shorted any of the motor leads. Make sure the jumper settings on the board match the steps/mm setting in the firmware.by the_digital_dentist - Reprappers
Re: Bulldog XL settings on prusa i3 was direct drive now 5 to 1 - 10 years ago
Since the motor is making noises, you have at least got the pairs of wires identified correctly (it would not make any noise or do anything else, otherwise). Try increasing current a little, and check that your acceleration, jerk, and speed settings aren't too high. If none of those get it moving, try reversing the connections of one pair only. The picture I previously linked says Red, Brown,Yby the_digital_dentist - Printing
Re: Bulldog XL settings on prusa i3 was direct drive now 5 to 1 - 10 years ago
Oops, it's 5.18:1 Here's the page:by the_digital_dentist - Printing
Re: Bulldog XL settings on prusa i3 was direct drive now 5 to 1 - 10 years ago
I believe the BullDog XL is a 5.13:1 gear ratio. RRDs info on the extruder says use 495 steps/mm, so start with that. You change the E steps/mm on the LCD.by the_digital_dentist - Printing
Re: Large envelope printer - 10 years ago
Moving mass is very high. Printers generally operate at higher speeds than CNC machines (there's no resistance to the motion of the head- we're not cutting anything). High speeds and high masses don't go together- Newton's laws at work.by the_digital_dentist - General
Re: Large envelope printer - 10 years ago
For a large envelope Cartesian machine, a bed that moves in the Z axis is the way to go. The mass of the bed won't matter because you only move the bed when the extruder is not extruding. Engine blocks are generally rectangular shaped objects. A cartesian type printer's bed is usable over almost it's entire surface. To print something 600 x 600mm, you need is a bed that's maybe 620 x 620mm.by the_digital_dentist - General
Re: Odd temperature readings - 10 years ago
The analog inputs where the thermistors are connected are subject to noise pickup that can lead to weird readings. The noise can come from running the thermistor wires too close to motor or extruder or bed heater wires, or AC power wires. Try shutting everything else off and pull other connectors off the board so that only the thermistor inputs are connected. Then add other connections back inby the_digital_dentist - Printing
Re: Large envelope printer - 10 years ago
If you're talking about a printer in which the bed moves in the Y axis, your biggest problem is going to be controlling the motion of that large moving mass, unless you don't mind very low print speeds. Fully supported rails or linear guides can easily fix the sag problems, as long as the frame of the machine is sufficiently sturdy.by the_digital_dentist - General
Re: Graphite Foil - 10 years ago
Uneven heating of a print bed is a non-problem. Anything that comes on a roll is going to have to have some mechanical support, so your heat spreader insulator idea is sort of pointless. If you have to have mechanical support, just use a piece of aluminum. The slightly uneven heating of a print bed using less exotic and very cheap materials like aluminum does not affect print quality. Using mby the_digital_dentist - General
Re: Large envelope printer - 10 years ago
I don't get it. I'm nuts for suggesting that scaling up a printer isn't rocket science, but people are talking about 1.5 cm steel plates and pretensioned guide rails? It really isn't that difficult. If you're worried about guide rails flexing, use fully supported rails or linear guides. If you want to make a rigid frame, use stuff that you know will work. I'm not a mechanical engineer. I doby the_digital_dentist - General
Re: Building a 12x12x12 + reprap, need a push in the right direction. - 10 years ago
Here's 12"x12" x 11.5" printer, at least the way it looked a couple months ago. I'm doing a major rebuild now... Here's part of the rebuild: I have a CAD file of the rebuild if you'd like to look at it.by the_digital_dentist - General
Re: what is the best extruder for abs? Struggling with mk8 direct drive... - 10 years ago
The BullDog XL runs at 600 mA and never gets more than a little warm. I've never had it chew up the filament, but only used it for a month or two. The springs that push the pinch wheel against the filament are very strong and you'll need to keep an allen wrench handy to change filament because it is really hard to compress the springs by hand unless you reduce the tension on the springs by backby the_digital_dentist - Printing