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Discuss here what makes your printer moving.
Re: core idex feedback - 4 weeks ago
You could anchor the bed hold-down springs with screws and t-nuts, or even just regular screws and nuts by drilling through the 4040. The motor offsets relative to the corner pulleys are determined by the need to keep the belts parallel to the y axis rails.by the_digital_dentist - CoreXY Machines
Re: core idex feedback - 4 weeks ago
Why can't you use a longer piece of 4040 for the bed support? I have found that there really isn't any need for the XY motors to go outside the printer enclosure, which would make it slightly easier to enclose the machine because you don't have to cut holes in panels for the belts. I suppose it depends on the enclosure temperature you use. I set it to 50C for printing ABS, which I don't do veryby the_digital_dentist - CoreXY Machines
Re: rhino worm gear - 5 weeks ago
That brass part is probably the hub of the disc gear, so there's no chance that it is bent. The error looks pretty small to me- probably a tolerance of fit issue. I wouldn't worry about it. You're going to put bearings at the ends of the shaft, so put them in the correct positions and mount the shaft. That long shaft will flex a little if it has to.by the_digital_dentist - CoreXY Machines
Re: rhino worm gear - 6 weeks ago
There's nothing yellow in my Rino. Can you post a picture? It's far more likely that the shaft is bent than anything in the Rino. Try rolling the shaft on a glass table or stone counter top. If it isn't straight it will be obvious. The screws on the disc that the shaft goes through are used to adjust for minimal backlash. I wouldn't touch them.by the_digital_dentist - CoreXY Machines
Re: rhino worm gear - 6 weeks ago
Still using it. I've never had any problems with it. Just printed this- 638mm tall, 923g of PETG, 1.2mm line width, 0.4mm layers, 15 hours at 40 mm/sec. I'm not home right now, but I'll take a look at mine when I get back. I don't recall anything yellow on mine.by the_digital_dentist - CoreXY Machines
Re: Stall detection for stepper motors - 2 months ago
I would think the drivers for such large motors would have multiple alarm conditions built-in, including stall detection.by the_digital_dentist - Safety & Best Practices
Re: what causes this gap ? (Prusa Slicer) 30$ reward - 3 months ago
Looks like it might be a z axis problem. If the Z axis doesn't move the full layer distance, the plastic will be squished outward and lines will be fatter than they should be. If it moves more than the full layer distance lines will be narrower than they are supposed to be. Another possibility is that the extruder carriage is shifting - does the concavity go all the way around the print, or doesby the_digital_dentist - Printing
Re: Bed temperature offset and stabilization - 3 months ago
QuotePCLoadPLA it seems incredible if everyone is printing a first layer 10+ degrees cooler than their nominal bed temperature without knowing it. Typical, not incredible. For some reason everyone wants to make their printer go as fast as possible and can't wait for the tugboat to finish before they start the next one. You think they'll wait a few minutes to let the bed heat up properly? Hah!by the_digital_dentist - Tech-Talk
Re: Opinion on 24AWG for hotend - 5 months ago
Wire current limits are based on the insulation material, and whether the wire is in a bundle (3d printer extruder cable) or in free air. Essentially, the resistance of the wire will cause it to heat up at higher currents. If the increased temperature causes the insulation to soften or melt, it's going to be a big problem. Same gauge silicone and PTFE insulated wires can handle more current thanby the_digital_dentist - Safety & Best Practices
Re: Homing vs. end-stop sensors - 6 months ago
All true. I just don't do any of it. I've been using a 1mm nozzle for a couple years and I'm getting tired of struggling to get good print quality from it - retraction and drooling are problems with large nozzles. It's great for large vases, etc., but doesn't do small parts or detailed parts well. I'm thinking I'll build another printer that will use a small nozzle for detailed work and smallerby the_digital_dentist - Tech-Talk
Re: border agglomeration issue - 6 months ago
I see two problems- under extrusion that is keeping perimeter and fill lines from sticking together, and the uneven spacing of the fill lines- they are in pairs - indicating some backlash or other mechanical problem. The lines should all fuse together, and spacing between fill lines should be even, not paired. I would try to fix the uneven spacing problem first, then the extrusion problem. If yoby the_digital_dentist - Printing
Re: Homing vs. end-stop sensors - 6 months ago
I don't bother mapping the bed at all. I just used a flat bed (cast tooling plate) with a same-size heater, and put it on a kinematic mount. The last time I leveled and zeroed it was over a year ago. When I do eventually relevel it, maybe in another year or two, it will take all of 1 minute to adjust two screws. Printers don't have to be made of cardboard and duct tape...by the_digital_dentist - Tech-Talk
Re: Homing vs. end-stop sensors - 6 months ago
Your semiconductor fab machines are typically moving much more weight, and driven by high torque steppers or servomotors and something very expensive may get damaged if the controller loses track of whatever is moving. 3D printers typically use low torque steppers and when properly set up, the controller always knows where the nozzle is, after the initial homing. With the low torque motors usedby the_digital_dentist - Tech-Talk
Re: Maybe a new 3d printer design? - 6 months ago
That would be more like an infinite X or Y axis. It might actually work if the floor it was rolling/printing on was perfectly flat. Are you planning to print with cake frosting or cement? Plastics often require a heated bed. That could be a problem. Keep trying!by the_digital_dentist - General New Machines Topics
Re: Tool for sanding disc brake pads - 8 months ago
I eventually came to realize that my squealing brakes problem was due to fluid leaks that had developed. I hunted for replacement seal kits for the brakes and couldn't find any, so I bought some Shimano OEM brakes that were already assembled. I just bolted them on the bike, cleaned the rotors with IPA, and it's working like new again. If you have disc brakes that squeal, they're probably leakingby the_digital_dentist - Look what I made!
Re: Positioning the z-axis endstop - 8 months ago
With an optical endstop when the flag enters the gap between the emitter and detector and is right at the edge of triggering, the output can bounce up and down a bit. In better optical endstops there is an LM393 comparator chip that adds a bit of hysteresis so that bouncing is eliminated. In mechanical endstop switches with a springy lever the spring adds mechanical hysteresis but the switch coby the_digital_dentist - Mechanics
Re: Positioning the z-axis endstop - 9 months ago
Are you using some sort of bed leveling sensor on the extruder carriage? If not you might want to use an optical endstop instead of a microswitch. Optical endstops are usually much higher precision devices, especially if the microswitch has a lever. The lack of precision can mean varying first layer thickness from print to print. I like optical endstops with a comparator chip that eliminates switby the_digital_dentist - Mechanics
Re: Z axis Kinematic or fixed industrial printer - 9 months ago
Sorry, but I can't quite figure out what you're asking. A kinematic mount is normally applied to the bed because it allows it to expand when heated without causing anything to flex. It is always a good idea to use a kinematic mount on the bed plate if it is heated. Three screws are used to lift Z more often than four because any error in the movement of four screws will cause the bed or XY staby the_digital_dentist - Reprappers
Re: Which Kit? Railcore? SecKit? Other? - 10 months ago
I'm not really familiar with the belt layouts people are using for IDEX, but the basic principle of keeping the working segments parallel to the guide rails will apply. If you think you might want to build with a single extruder and convert to IDEX at some point in the future, it would be best to design the XY stage to accommodate that now- trying to shoehorn an additional extruder and mounts forby the_digital_dentist - CoreXY Machines
Re: Which Kit? Railcore? SecKit? Other? - 10 months ago
I wouldn't cut the frame pieces yet! If you do you'll have to figure out how to stuff everything into the frame. It's better to design the stuff that goes in the frame first, then figure out the frame pieces needed to enclose it. Since you have decided on the print volume, I'd start by designing the extruder carriage first, then the rest of the XY stage. It will have to be 400-450 mm square to aby the_digital_dentist - CoreXY Machines
Re: What is the cause of magical random ripples on the Core XY printer? - 10 months ago
I see two problems in the prints you have posted. There are regularly spaced vertical ripples in both X and Y sides of the print, and there are semi random ripples in the Y axis side of the print. If you print the same box multiple times, do the semi random looking ripples look identical in each print? I asked about the diameter of the bearings you are using for pulleys (you gave no answer) beby the_digital_dentist - CoreXY Machines
Re: What is the cause of magical random ripples on the Core XY printer? - 10 months ago
I don't know if helical gears are supposed to fix the problem associated with dual drive gear extrusion. If you have a single drive gear extruder available, give it a try and see if the problems persist. What is different when the extruder moves in X and when it moves in Y? With Y axis movement the Y axis linear bearings move and the corner pulleys and pulleys at the motors turn. With X axis moby the_digital_dentist - CoreXY Machines
Re: What is the cause of magical random ripples on the Core XY printer? - 10 months ago
Post some pictures of the prints. Are the problems only on the Y axis and not on X axis? Dual drive gear extruders such as the BMG and Sherpa Mini are known to cause uneven Z axis surfaces due to poor meshing of the gears.by the_digital_dentist - CoreXY Machines
Re: CubePro Upgrade 2023 - 11 months ago
See this thread for starters:by the_digital_dentist - General
Re: 3D printed sand table mechanism - 1 year ago
Update: The plywood bottom of Arrakis' sandbox was warping with changes in humidity, causing the normally air-gapped magnet to drag against the bottom of the sandbox, making a scraping noise. I solved that problem by using a piece of 5mm thick glass for the bottom of the new sand box. This time I used contact cement to mount fake white leather on the table bottom surface so you can't really see iby the_digital_dentist - Look what I made!
Re: CoreXY X axis wobble - 1 year ago
No, that would be a precision problem. The error is one of accuracy, not precision. A long, flat surface parallel to the printer's X axis would have waves corresponding to the displacement caused by the out of round drive pulley(s). I have never actually seen such a wave. The stacked potato chip Z surface is more likely caused by using a geared extruder with two drive gears. Seeby the_digital_dentist - CoreXY Machines
Re: Intermittant diagonal layer shift, how to diagnose? - 1 year ago
Good find!by the_digital_dentist - CoreXY Machines
Re: TronXY X5SA 330x330 bed thicker? Impossible to tram with 6 set screws! - 1 year ago
What is the Tronxy bed made of? Does the X axis sag or is the bed warping upward?by the_digital_dentist - CoreXY Machines
Re: My printed circles are oval - 1 year ago
Check belt tightness, make sure drive pulleys are securely screwed to motor shafts, set speed and acceleration to lower values, make sure motor and pulley mounts are solid, use glass core belts instead of steel core belts. Post photos of machine...by the_digital_dentist - CoreXY Machines
Re: Heated Beds - 1 year ago
siblues - heaters are typically attached to aluminum plates using 468MP adhesive. If that is all that holds the heater on the plate, the adhesive will let go after a couple years of use. Keenovo's manual says the edges of the heater should be sealed using silicone caulk, presumably to prevent the adhesive from letting go. But there's a better way- don't use 468MP adhesive at all. I've had the heby the_digital_dentist - Mechanics