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General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: Life span of plastic parts? - 8 months ago
You can buy metal mounts from China for $42 each (incl shipping to US), hogged out of a solid billet of aluminum (overkill, I'd say, but pretty)- you still have to add mounting holes or tap the holes for mounting the motor on the mount: My tube based mounts are a lot cheaper to make if you have a drill press.by the_digital_dentist - CoreXY Machines
Re: Life span of plastic parts? - 8 months ago
No, didn't follow existing design. I did that 4 or 5 years ago, and haven't seen it used by anyone else. Click the link on Ultra MegaMax Dominator in my sig, below to see more of it.by the_digital_dentist - CoreXY Machines
Re: Life span of plastic parts? - 8 months ago
I made motor mounts out of rectangular aluminum tubing- very cheap, and easy DIY, even with limited tools. They don't flex under belt tension, transfer heat away from motors (though in my printer, they may actually be transferring heat to the motor when the chamber heater is in use), and automatically provide an accurate, square mount. You can attach them to the printer's frame with screws in theby the_digital_dentist - CoreXY Machines
Re: Life span of plastic parts? - 8 months ago
Quotedekutree64PLA cracks ... and softens ..., but otherwise holds up just fine. Otherwise? All that, and don't ever transport your printer full of PLA corner braces, motor and pulley mounts in a car on a sunny day and stop for coffee...by the_digital_dentist - CoreXY Machines
Re: Life span of plastic parts? - 8 months ago
I have built multiple machines that use ABS motor and pulley mounts and belt clamps. If they are well designed and printed with appropriate settings, they last without adjustment or replacement (in my case, some under chamber temperatures of 50C for printing ABS). That said, there are reasons to use metal wherever possible. Metal mounts can conduct heat away from motors. Metals can be drilled, miby the_digital_dentist - CoreXY Machines
Re: Verticle belt movements on idlers - 9 months ago
t might be very hard to detect the tiny amount of tilt that would be required to cause the belt to move up/down. As I said, it probably isn't a problem as long as the belt doesn't climb into the pulley flanges.by the_digital_dentist - CoreXY Machines
Re: CoreXY Design Alternative - 9 months ago
Maybe I was wrong about linear motors...by the_digital_dentist - Mechanics
Re: Verticle belt movements on idlers - 9 months ago
Tilted pulley axles can cause this. Are the pulley axles supported at the top and bottom? It's probably not going to affect print quality unless the belts start climbing onto the pulley flanges.by the_digital_dentist - CoreXY Machines
Re: Design questions - 10 months ago
If you have bent screws in Z, they can create repetitive errors in the Z axis of prints by causing lateral shifting of the bed/print layers. That problem can be prevented by anchoring the bed to the Z axis bearing blocks and letting it float on the Z axis nuts. If you drive multiple screws with a single motor, you have to use belts and pulleys to connect the motors and screws. If the pulleys areby the_digital_dentist - CoreXY Machines
Re: Design questions - 10 months ago
1) it depends on multiple factors. Belts are driven by something- pulleys, gears, etc. If those are poor quality, they will create repetitive errors in the Z axis of prints. Of course, you can have poor quality ball screws, too, but they're less likely to create repetitive patterns in the prints. Belts are a LOT cheaper than ball screws, especially if you're using more than one, and especially ifby the_digital_dentist - CoreXY Machines
Re: New Bed Leveling - 11 months ago
Now let's see the same plot overlayed on that one at different temperatures...by the_digital_dentist - Developers
Re: New Bed Leveling - 11 months ago
Inductive sensors have been around for a long time, and most were abandoned a few years ago because they were not consistent over the temperature range seen in 3D printers with heated beds. Does your inductive sensor work reliably over a wide temperature range?by the_digital_dentist - Developers
Re: Print spool holder for 30x30 T-Slot frames - 11 months ago
IRIC, the Ratrig printer is open frame which means most people will probably be printing PLA on it a lot. It has been my experience with full spools of filament, especially PLA which is very stiff and springy, that the filament loves to jump off the spool over the flanges resulting in tangles that will ruin prints. For that reason I use a spool holder that has rollers that contact the flanges ofby the_digital_dentist - CoreXY Machines
Re: With AC mains heated beds... safely... - 11 months ago
The neutral side of the line is normally not fused because it connects to the ground wire at the breaker box.by the_digital_dentist - General
Re: Quality Parts - 12 months ago
If you're working off someone's BOM instead of designing your own machine, you're sort of stuck using whatever they chose to use, often because it was the cheapest available part. But if you have access to tools and a working brain, it usually isn't too difficult to substitute good parts for crappy ones. I prefer to buy quality used linear guides via ebay instead of poorly made, no-name HiWin knoby the_digital_dentist - Mechanics
Re: Exoslide Core XY with "trough" down the middle of the bed? - 1 year ago
Is the glass flat?by the_digital_dentist - Reprappers
Re: Silicone heatbed brand suggestion - 1 year ago
Whatever heater you use, I suggest you get it without adhesive and use high temperature silicone to mount it. The pressure sensitive adhesive they supply has a tendency to let go after a couple years of heating and cooling. And don't mount it on a piece of glass.Use a thick aluminum plate to spread the heat.by the_digital_dentist - General
Re: Isothermal Heated Bed - First Pass - 1 year ago
IR guns aren't the way to measure temperature of glass. They are calibrated to specific emissivity targets. You're more likely measuring the temperature of whatever is under the glass or reflected by the glass than the glass itself, where the molten plastic will be deposited. A thermal camera may give a better visualization of the temperature distribution, though absolute accuracy, especially onby the_digital_dentist - Tech-Talk
Re: Servomotor disaster - 1 year ago
The diode is normally forward biased which holds the transistor off. When there's a voltage spike at the motor that exceeds the supply voltage (24V in this case), the diode gets reverse biased and that turns on the transistor. The current through the 33 Ohm resistor will depend on the magnitude of the voltage at the output, not the input supply voltage. If the spike goes to 80V, there will be aboby the_digital_dentist - Stepper Motors, Servo Motors, DC Motors
Re: Servomotor disaster - 1 year ago
I prepared a PCB and gathered most of the parts for the returned energy dump. I ran a simple test and it appears to work properly. Details, including a link to the KiCAD PCB design files is here. Video or it didn't happen... Note: I wired it without the power in/out connector because they have been back-ordered for 4 months (so far).by the_digital_dentist - Stepper Motors, Servo Motors, DC Motors
Re: Stepper driver selection - 1 year ago
The Duet 3 controller board could drive those motors directly without any additional heatsinking (though you would probably want to have a fan blowing on the board). The Duet ecosystem is under active development, has an active forum (primarily in English which helps some of us), and loads of online documentation.by the_digital_dentist - Stepper Motors, Servo Motors, DC Motors
Re: DIY CoreXY - 1 year ago
It sounds like the person who generated the rsdoc file was trying different options or made updates after the initial design and left the original in the file. I do that sort of stuff all the time, especially as I make updates to my printer. I try to give new names to new parts so that I can distinguish between the different designs contained within the same CAD file, and switch on just the onesby the_digital_dentist - CoreXY Machines
Re: DIY CoreXY - 1 year ago
Define "complete". Define "not an arm and a leg". Define "your purposes". You were already talking about modifying an existing design to use 4 guide rails and 2 motors in the Z axis. You can apply the same thought processes to the rest of the machine. Look at multiple designs, be critical and list the good and weak points, then choose one to start your design, and try to fix the weak points as yby the_digital_dentist - CoreXY Machines
Re: DIY CoreXY - 1 year ago
Getting four round rails parallel to each other is going to be tricky. It is much easier to get two linear guides parallel to each other...by the_digital_dentist - CoreXY Machines
Re: DIY CoreXY - 1 year ago
You're going to cantilever a bed on end-supported round rails anchored to a 2020 t-slot frame? I think it's going to bounce like a diving board! This might be a good time to learn some CAD skills. RSDOC is a Design Spark Mechanical format. DSM is free and very easy to learn.by the_digital_dentist - CoreXY Machines
Re: Layer height as an integral number of Z steps - 1 year ago
Yes, it is generally best to set the layer thickness to an integer multiple of the full step movement. It is also best to design parts so that features like horizontal steps that occur at different Z heights are a multiple of the layer thickness. My printer has a full step Z resolution of 20 um, so I use multiples of 20 um to set layer thickness. That means I can have 0.1 mm layers, or 0.2 mm lby the_digital_dentist - Printing
Re: DIY CoreXY - 1 year ago
You have printers that you can use until your corexy machine is operational. Why spend time and effort making something "upgradeable" when you can just take a little longer and build the "final" machine?by the_digital_dentist - CoreXY Machines
Re: Extruder stops after a few minutes but x,y,z continue normally - 1 year ago
The driver chip may be over heating and going into thermal shutdown. Why does one do it and not the other? You're probably operating at the edge and one goes over and the other doesn't. Try turning the current down a bit and see if it still stops working. Those little modules suck, TMC drivers or not.by the_digital_dentist - Printing
Re: My 1st home made 3D printer - 1 year ago
Interesting build. I think the original FDM printers were made with screws driving all axes. One of the reasons people use belts instead of screws is the much faster movement you can get using belts. What sort of print speeds do you anticipate?by the_digital_dentist - Look what I made!