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People building or using RepRaps.
Re: Source for nema 17 sized shaft bolt - 10 years ago
If you're talking about a screw that goes through the side of a ring and clamps it to the motor shaft, it is called a grub screw. The part you have will already have threads for a specific size. You'd better check the part specs.by the_digital_dentist - Mechanics
Re: What Softwares are you Using? - 10 years ago
Yes, they will be polygons in gcode, but the fact that circles are never circles in Sketchup leads to weird drawing problems and holes in stl files. For example, try to move two cylinders together so they touch. Once you're pretty sure you've got it, zoom into the contact area. Unless you happened to get lucky and accidentally connect polygon vertices together, the two won't be touching at a lby the_digital_dentist - 3D Design tools
Re: What Softwares are you Using? - 10 years ago
I like DesignSpark Mechanical. The UI is very easy and it is about 10X more powerful than the free version of Sketchup. Unlike Sketchup, circles are actually circles (not polygons), so it produces water tight STLs with a lot of control over the STL file resolution. You can easily do things like fillet or chamfer edges/corners, draw threads, draw lines, arcs, and circles that are tangent to othby the_digital_dentist - 3D Design tools
Re: Help me find a 3dprinter heatbed. - 10 years ago
Everything is OK until it isn't. I hope you have continued good luck with no one getting injured or killed.by the_digital_dentist - Mechanics
Re: How to alter an STL part design, or easly read dimensions for redesign? - 10 years ago
DesignSpark Mechanical seems to be able to do measurements from and edit STL meshes. I just discovered that a couple days ago.by the_digital_dentist - 3D Design tools
Re: Twisted String Actuators - 10 years ago
It seems best suited to moving objects at low speeds with moderate/strong force but poor precision. Precision could be improved by adding an encoder. You'd need a string pulling in the opposite direction to reverse the motion. Is linear displacement per rev constant? I don't think so. I wonder how long the twisting "string" would last.by the_digital_dentist - Mechanics
Re: cleaning abs juice off parts printed - 10 years ago
Hot ABS likes to stick to Kapton tape with no messy juice, hairspray, or other junk necessary. No cleanup, either.by the_digital_dentist - Printing
Re: Problems with Bulldog light extruder and Hexagon - 10 years ago
There are a number of things to look at. The regularity of the blobs says maybe the drive gear on the extruder motor is dirty (full of plastic powder from grinding filament), or slipping on the motor shaft- check the grub screw(s). Another possibility is that the motor current is set either too high or too low. If the motor gets very hot it is probably too high. If the motor doesn't get warmby the_digital_dentist - Printing
Mounting E3D V6 hot end on BullDog XL extruder - 10 years ago
I got one of each for my printer and then had to put them together. The E3D V6 I got uses a small teflon tube inside the heat sink and a tube retainer at the extruder interface that sticks up about 1 mm. The first problem I ran into was that collar of the hot-end was too wide for the groove in the BullDog's foot. I used a small file to put a couple flats in the E3D mounting collar so it wouldby the_digital_dentist - Mechanics
Re: Extruder stepper motor temperature? - 10 years ago
Nope. Typical. The extruder is working hard continuously throughout the print. You usually need to run the motor close to rated current to get sufficient torque to do the job. Running near rated current gets you near rated temperature rise. If you're concerned about it you could try turning down the current a little at a time and see when the extruder stops working properly, then bump the cuby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
OK, a lot has happened in the last couple weeks. I installed the SmoothieBoard and DSP driver/32V supply for the Y-axis. I had some problems with the Smoothieboard at first but they were solved by replacing the uSD card that came with the board with one purchased from Walmart. The machine has been cranking out beautiful prints running up to 100 mm/sec. I've been redesigning/building a replaceby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Steel balls will chew grooves into aluminum very quickly. Look into something like this: You can often find used ones for reasonable prices and they are much more precise than round rails.by the_digital_dentist - Mechanics
Re: BullDog XL Extruder dimensions - 10 years ago
Over-engineering is what I do: http://mark.rehorst.com/MegaMax_3D_Printer/index.html Are you able to get quality prints with the extruder "secured" that way?by the_digital_dentist - Mechanics
BullDog XL Extruder dimensions - 10 years ago
OK, in spite of hundreds of people asking, and thousands of these things being sold, no one has provided dimensions that would let you design your extruder carriage, check fit in your printer, etc. Until now. Here are the base plate dimensions, modeled as closely as I could with a caliper and a scale. The model is as complete as I intend to make it. Dimensions have been checked andby the_digital_dentist - Mechanics
Re: Best Z axis coupler? - 10 years ago
8mm threaded rod is less likely to get/be bent than 5mm. Motors can get hot when operating for long periods. That includes the shaft. I think ABS would be better, but PLA might be OK depending on how much current you run through the motor. I edited the file for 5mm and 8mm shafts and M3 grub screws. The shaft holes are just a little oversized so that when they print they'll fit the shafts tiby the_digital_dentist - Mechanics
Re: Best Z axis coupler? - 10 years ago
If you know someone with a printer, I can send you an stl file of a shaft coupler. Give me shaft diameters, lengths available for grub screws, and overall length of the coupler and I can send the stl. As an alternative, I have an rsdoc file of a design that I can send you if you use DesignSpark Mechanical (it's free!) and you can make the necessary changes your self. You can see a picture of tby the_digital_dentist - Mechanics
Re: Optimum Z axis steps/mm - 10 years ago
There's a lot to consider here but the answer is pretty simple... The motor driver probably does microstepping. Microstepping isn't as precise and torque is lower compared to using the motor's native full steps. In the X and Y axes the extruder moves continuously so the microstepping helps keep the motors running smoothly. In the Z axis you're normally just bumping the X axis up by 50-200 umby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
The new driver and smoothieboard are in and connected along with the 32V supply on the Y-axis. Result: the DSP controller, power supply, and higher torque motor throw the Y-axis around like it isn't even there and the thing wails like a banshee! The print bed is an aluminum plate stood up by three screws at its edges making it a perfect, harsh resonator. I'm still doing some tuning and tweakinby the_digital_dentist - Mechanics
Re: Fixed/Mobile choice in X,Y,Z axis and in Extruder configuration? - 10 years ago
There's a design that moves a single guide rail in X and a single guide rail in Y and uses a bowden extruder, and moves the Z axis downward during printing. A guy on Google+ named Shauki Bagdadi (https://plus.google.com/u/0/+ShaukiBagdadi) has built such a printer using cables to drive the X and Y axes and he runs the thing at 250 mm/sec. I suggest you get on Google+ 3D printing group because hby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
A few comments: One of the first problems 3D printing noobs run into is getting the prints to stick to the print bed. Some people spray their bed with hairspray, others use "ABS juice", others use glue sticks. Kapton tape works well and isn't as messy as any of those, but costs a little more. The heated bed is necessary to keep the ABS part stuck to the kapton tape on the surface of the bed. Iby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
That's encouraging! The new motor is in and bolted to the machine, waiting for the driver to arrive later this week. The driver is good up to 50V, but my power supply is about 32V under load. I'll try the driver and power supply with both motors. If I have to I can build a higher voltage supply- I have a transformer that can easily do the job.by the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
I'll be installing a DM542 driver module (http://www.americanmotiontech.com/upload/Manuals/DM542m.pdf) and replacing the AT Mega2560/RAMPS boards with a SmoothieBoard. The SmoothieBoard can provide up to 200k pulses per sec to the steppers compared to the 40k pulses per sec with the ATmega2560. That means I can increase microstepping which is supposed to help with vibration, especially at low sby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
OK, after some study I believe I have a handle on the vibration problem. It is inherent in the steppers- the detent force required to make it go from one step to another causes the vibration at low speeds and resonance effects cause it at higher speeds. The driver on the RAMPS board is no help- it is just a dumb driver that is capable of microstepping. All is not lost! A decent stepper driverby the_digital_dentist - Mechanics
Re: ABS delamination from heatbed - 10 years ago
You have two issues: adhesion to the bed and delamination. Adhesion is a matter of getting the right material on the bed surface and leveling the bed accurately. I like kapton tape and rarely have adhesion issues when printing ABS on clean kapton tape. I wipe the bed with acetone before printing (don't use finger nail polish remover- it contains stuff like glycerin that won't help parts sticby the_digital_dentist - Printing
Re: Fixed/Mobile choice in X,Y,Z axis and in Extruder configuration? - 10 years ago
Quoteerosnicolau Hi, there, I've been researching different 3d printer configurations lately and I saw pretty different approaches in how to choose what's fixed and what's moving in a 3d printer. Basically, 2 rules apply generally: - the lighter the moving parts, the speedier the print can be - the lighter the moving parts, the less inertia, resulting in the more precise printing. ... Thanks foby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
Well, screw drive is definitely noisier than belt drive. I installed the screw drive mechanism last night and tried a test print. At certain speeds the thing vibrates a lot. When you think about it, it makes sense because there's no belt to buffer the vibration from the motor- just a lot of metal to metal contact throughout the drive mechanism. One interesting change in the sound profile is tby the_digital_dentist - Mechanics
Re: Vibration/noise problem - 10 years ago
Update: the screw drive vibrates badly at some speeds. I decided to beef up the undercarriage plate to 1/4" cast aluminum tooling plate. I also replaced the printed plastic standoffs with aluminum tubing. The new configuration has the reference side set up with a 280mm long piece of aluminum tubing for the standoff screwed to two bearing blocks. The other side has a short piece of tubing scby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
You can print with ABS on PIR (polyisocyanurate) foam without heat. I have not tried printing on it with PLA. PIR foam is sold in big sheets for building insulation. In the US a 4' x 8' x 1" sheet costs about $15 (PIR foam sheet at Home Depot). You can cut it to the size you need with a razor knife. Stratasys FDM machines print on polyurethane foam. I've been told they charge about $70 US fby the_digital_dentist - Mechanics
Re: Design questions - 10 years ago
If you don't bury the nozzle too deeply the effect is to push the foam down without tearing it up. In the first video you can see an area in the upper left corner of the foam where I buried the nozzle too deeply and it tore the foam up a bit. The foam is soft enough that it gets out of the way when the extruder is pushing plastic against it. I did not have any problems with clogged nozzles- noby the_digital_dentist - Mechanics
Re: Help me find a 3dprinter heatbed. - 10 years ago
Any CAD program should be OK for any size bed. I have been using DesignSpark Mechanical a lot and find that I rarely run into its limitations. If you're looking for really simple, try Sketchup.by the_digital_dentist - Mechanics