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People building or using RepRaps.
Re: Ammissible deflection in 3d printing - 10 years ago
Very tiny. Everything that causes the extruder to deviate from the gcode path in the XY plane will have a visible effect in the print. Even vertical errors will be visible because the plastic line being laid down will vary in width. The prints we make can still be functional and aesthetically pleasing even with the errors- that is why there are so many machines using laser cut plywood in the sby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
Looks like a great printer! Much more presentable than MegaMax. What temperature do you run inside the cabinet when printing ABS? Is all the heat provided by the print bed and the motors or do you have an additional heater? I normally run my printer inside a thermal enclosure (http://www.thingiverse.com/thing:269586), letting the print bed heater provide all the heat. It takes about 5 minuteby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
Right now I'm running the motors off the 12V supply. I am considering switching to 24V. What is your experience with running the higher voltage on the motors?by the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
QuoteGarry Bartsch Sorry I can't comment on the vibration but that's a wicked looking Heavy Metal printer. How's it's print quality? It's pretty good, but I am always striving to make it better. More photos of the printer and some recent prints for the SnakeBite extruder here: https://drive.google.com/drive/#folders/0BxckS0Y4E9lzN1hlOGtaeUdZcUU QuoteA2 It looks to me like the idler belt pullby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Quotecozmicray jaguarking11 Point taken -- you sound like an electrical engineer Please comment on the use of a 120V AC heated bed on a 3D printer since the expert, the_digital_dentist, has stated that it isn't a good idea? Thanks Before I was a dentist I was an electrical engineer for 22 years. I can state unequivocally that low voltage is safer than high voltage. Comparing commercial prby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Connecting 110V to the printer isn't a good idea because of potential safety problems. In order to be safe you'd have to connect through a transformer, but if you';re going to do that, you may as well use a lower, safer voltage. Glass plates are fine for unheated beds, but glass is a poor conductor of heat and you'll end up with hot and cold spots. Some people use an aluminum bed to spread theby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
I just ordered some 9mm wide GT2 belt and pulleys from Folger and will give that a try to see if it helps either the vibration problem or print quality. The pulleys are for 5mm shafts so I'll have to bore them out to 1/4", but that will be quick and easy. I am now preparing to try a ball screw drive instead of the belt. I pulled a ball screw assembly from a scrapped industrial machine and madeby the_digital_dentist - Mechanics
Vibration/noise problem - 10 years ago
My printer has 12"x12.5"x 1/4" cast aluminum tooling plate bed riding on and aluminum undercarriage with 4x Thompson Super 8 ball bushings and 1/2" guide rails. The bed is moved by a NEMA-23 stepper with a 5mm pitch, steel core, urethane drive belt and matching pulley. When printing at low speeds the whole thing vibrates and makes noise. If I disable the motor current and push it by hand I getby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
You know it is possible/easy to print with ABS on unheated PIR foam. I have done it- see As you can see, it sticks quite well! I got the idea from an industrial Stratasys 3D printer that prints on expensive polyurethane foam blocks. No, the bottom surface won't be as smooth as it would on a glass or aluminum bed, but most of the time that smooth bottom surface isn't needed. The Strataby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Hmmm. You're talking about casting a plate. Then you have to finish it. I would consider the time, effort, tools, and materials all that would take, and the low probability of success, and then ask myself what is my time/labor worth and is that really the sort of problem I want to devote my energy to. For me, no. Maybe you have different priorities. You could buy rod stock and a tap and dieby the_digital_dentist - Mechanics
Re: Homemade vibration damper for stepper motor - 10 years ago
Don't the screws transfer the motor vibration to the frame?by the_digital_dentist - Mechanics
Re: Astrosyn Dampers (Reduce vibration and printer noise!) - 10 years ago
I have a ginormous printer that uses NEMA 23 motors and is too loud. Did you ever get an order together for some of the dampers for NEMA 23s?by the_digital_dentist - For Sale
Re: auto bed compensation via end-stop-wired bed mounts - 10 years ago
John, It sounds like the autoleveling scheme is actually much better and more useful than I would have thought. When I built my machine I went for maximum rigidity and used 1.5" 8020 for the frame. For an example of the result, I recently threw the machine (OK, I set it down gently) in the back of a pickup truck, drove it to the Milwaukee Maker Faire, turned it on and started printing withoutby the_digital_dentist - Mechanics
Re: auto bed compensation via end-stop-wired bed mounts - 10 years ago
As I understand it, this "bed leveling" technique will result in all layers being skewed in the Z-axis by the amount of the error in the physical level of the bed. It seems to me you're trading a relatively small problem for another small problem with a lot of complexity thrown in for fun. To use your example, if the far side of the bed is 1mm higher than the near side, your print of a cube wilby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Glass doesn't conduct heat so you'll end up with a lot of hot/cool spots. There are some circular pieces of tooling plate about 400+ mm dia that are pretty cheap on ebay.by the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
A little bigger than you need:by the_digital_dentist - Mechanics
Re: Kossel Extruder Not Turning - 10 years ago
The difference between your printer and the thing you used to test the motor is the cable from the controller board to the extruder motor in the printer. When you tested the motor you didn't use THAT cable. Steppers don't turn if there's an open connection, a shorted connection, or a couple swapped wires. Check the cable.by the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
You will need to get aluminum "tooling plate". Extruded plate is always curved. Tooling plate is cast, and milled to guaranteed flatness. Extruded plate will tend to warp when heated, cast plate expands but doesn't seem to warp as much (probably due to more amorphous structure). I use 1/4" x 12" x 12.5" tooling plate in my printer and can print edge to edge. I don't know if you can get 20"x2by the_digital_dentist - Mechanics
Re: DesignSpark Mechanical - 10 years ago
I'm no expert, but I use Designspark Mechanical a lot and like it. My training on it is strictly as needed- when I want to do something I haven't done before and I go to the web to find out how to do it. I used to use sketchup but kept running into the limitations- curves/circles are never actually curves/circles which causes numerous mysterious problems with STL files. A lot of things thaby the_digital_dentist - 3D Design tools
Re: Max length of GT2 6mm - 10 years ago
I have steel reinforced 9mm wide 5mm pitch belts (don't know the exact designation- they came out of a piece of industrial scrap) on the X and Y axes of my printer. The Y axis span is about 700mm. It used to bounce a lot as the printbed moved and I considered putting a piece of soft sponge or something against it to control the bouncing but never got around to trying it. I did put a 1/2 twistby the_digital_dentist - Mechanics
Re: Belt on flat surface - 10 years ago
I have used toothed belts on smooth pullies. In my printer Y axis the motor is about 700mm from the pulley. When the toothed belt rode the smooth pulley I found two things: the print has tiny bumps in the surface that I attributed to cogging of the Y axis as the bums on the belt met the pulley (this causes small changes in Y axis speed that result in modulation of the thickness of the line of pby the_digital_dentist - Mechanics
Re: Belt on flat surface - 10 years ago
Are you asking about using a toothed belt with a smooth, untoothed pulley?by the_digital_dentist - Mechanics
Re: Steppers hesitate - 10 years ago
Check the motor current settings on the driver board(s).by the_digital_dentist - Mechanics
Re: Heatbed vs 3d printer size - 10 years ago
Putting the electronics under the printbed sounds like a good way to keep the printer small, but you might want to reconsider. You are making a pretty big printbed, so I assume you are going to want to make big prints. If you try to make big prints with ABS and you don't enclose the printer your big prints are going to delaminate even as they are printing. I suggest that you enclose the printeby the_digital_dentist - Mechanics
Re: power question - 10 years ago
A mechanical relay on the printbed heater circuit will drive you nuts with all the clicking, and probably won't last long because of the large current being switched. You don't need to use a relay at all if you have a 12V heater, as long as the current is less than about 10A. The MOSFET on the RAMPS board will switch the full 10A for you without complaint. I have moved away from switching poby the_digital_dentist - Mechanics
Re: power question - 10 years ago
The RAMPS board allows you to power the printer from two different supplies. They don't have to be the same voltage. One supply, typically 12V, drives the board, electronics, and motors. The other is just for the printbed heater. The printbed heater side has a MOSFET switch and a thermal cutout (a varistor?) that will shut down power to the printbed if you try to drive too much current for thby the_digital_dentist - Mechanics
Re: Heatbed vs 3d printer size - 10 years ago
I have a 12"x12.5" bed with a 24V, 450 Watt heater. There is no effect on the controller- a standard, unmodified RAMPS board. I power the heater from a 24V transformer and switch power into the transformer using an SSR connected directly to the RAMPS board. The SSR doesn't even get warm, and the bed heats to 105C in about 7 minutes. I used to use a switching power supply but burned it up in sby the_digital_dentist - Mechanics
Re: Printer stops extruding PLA after about one minute, running out of options. - 10 years ago
Good!by the_digital_dentist - Mechanics
Re: Printer stops extruding PLA after about one minute, running out of options. - 10 years ago
Check the filament where it is pinched between the gear on the motor and the bearing. Is there a round divot cut into the filament? If so it indicates that the hot-end is jamming. Play with the temperature setting of the hot-end- don't trust the electronics to read the correct temperature unless you can verify it for yourself with a reliable thermometer- either a thermocouple or RTD. If you cby the_digital_dentist - Mechanics
Re: Bed leveling issues - 10 years ago
The bed leveling serves only one purpose: to get the first layer of your print to stick to the bed. The bed has to be level relative to the extruder nozzle at all points on the bed so that when the nozzle visits those places it will "press" the plastic onto the bed with equal pressure everywhere. That means you must move the extruder nozzle around the bed in order to check and level the bed. Aby the_digital_dentist - Mechanics