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Discuss any sort of mechanical stuff here: positioning systems, gears, extruding methods, etc.
Re: Open or closed 3D printer? - 9 years ago
I find with pla the enclosure isn't really needed so open the door with pla. I leave mine closed but that's because my printers are in an outbuilding and the ambient air temperature is 5-10 deg C. If the printer was indoors at 20 deg C I'd leave the door open. A controllable print/layer fan is required for pla where the layers are small ie have a short layer time so not much time to cool. For aby DjDemonD - General
Re: ABS or PLA for prusa i3 rework printed parts - 9 years ago
I've always found pla very unforgiving when printing any functional parts, it's just too brittle to allow for a little wiggle room, such as a little flexibility to push bearings in etc...by DjDemonD - General
Re: Open or closed 3D printer? - 9 years ago
You have the best and easiest configuration for fully enclosed, it's a cube and the motors and electronics can be kept out of the enclosure. I noticed big improvements with an enclosure but it was harder to do with an i3 than a corexy. You can also then vent fumes out of the area where your printer is located by fitting a tube preferably venting to the outside. A small fan helps to circulate aby DjDemonD - General
Re: Bowden setup with flexible element - 9 years ago
I've not tried flexible but have recently changed from a bowden extruder to something different as I found the compressibilty/stetching in pla/abs too great to get very precise filament control. So I'd expect much more sloppy filament control with flexible filament. Shorter tubes will give less trouble and 3mm will work better than 1.75mm. Cant help but think a direct extruder would work betteby DjDemonD - General
Re: [Help] Capacitive sensor acting weird - 9 years ago
It's a normally open sensor so the led should only come on when it is placed next to a surface. Test the sensor first connect negative and +12v leave the signal wire unconnected. The led should be off. Bring the sensor near a surface usually around 2-4mm away the led should come on. If you now put a multimeter from negative to the signal wire you should be reading 0v when nothing is nearby andby DjDemonD - General
Re: Delta pulley and idler dimensions question - 9 years ago
I'm thinking about going over to 16 tooth drive pulleys and these idler pulleys that should improve resolution and provide reliable idlers. The 3mm bearing will wear on the 3mm bolt but at an acceptable rate. Why not use quite large idler pulleys to reduce their rate of rotation, this should reduce noise/vibration and bearing wear?by DjDemonD - Delta Machines
Re: backlash eliminating star - 9 years ago
Seems like a good idea. Makes me wonder if I am inadvertently achieving the same effect with a flying extruder since the extruder is attached by elastic to each of the carriages effectively pulling them towards the centre of the printer.by DjDemonD - Delta Machines
Re: Y motor not working - 9 years ago
All good advice thank you. I'll start by inspecting the mega and ramps carefully for bad solder joints. I checked the wiring to the motor but maybe it has an intermittent connection. I do have a scope albeit a very basic pocket type unit so this might have to be dusted off and fired up. That being said they're such cheap boards maybe replacing them is easiest if less satisfying.by DjDemonD - Delta Machines
Re: 0.9 deg steppers versus 1.8 with ramps - 9 years ago
Thanks David. I found this thread on Google groups which you contributed to which provides a very detailed discussion of this issue. I think I might just try 16 tooth pulleys at this stage the jump up to 100 steps/mm should be manageable.by DjDemonD - Delta Machines
0.9 deg steppers versus 1.8 with ramps - 9 years ago
I current have 1.8 deg steppers on my kossel mini running off a ramps board. 0.9 degree steppers should offer better resolution but will the increased steps required to drive them be too great for a ramps board to handle?by DjDemonD - Delta Machines
Y motor not working - 9 years ago
I've got a t3p3 kossel mini running on ramps/mega. Working fine for 3-4 months until the y tower axis stopped moving. I swapped over the stepper drivers but no joy, then I swapped them back and it started working. A little while later it stopped working again, so I swapped the y motor onto another channel and it worked. So I am at a lost, it doesn't appear to be the stepper motors or driverby DjDemonD - Delta Machines
Re: D8 MOSFET - 9 years ago
There is a thread about safer mosfets that can be used which have a built in protection against this problem. Also you might want to consider this fire safety deviceby DjDemonD - General
Re: assign pin to cooling fan - 9 years ago
I think that's what he's asking for help with, I'd love to know too....by DjDemonD - General
Re: mirror/inverse print - 9 years ago
There might be a market for a multitool leatherman-type thing for 3d printers?by DjDemonD - General
Re: mirror/inverse print - 9 years ago
As for building it in your living room, no you will never get to put your tools away, there is always something broken, that needs adjusting or upgrading.by DjDemonD - General
Re: Good beginner printer? - 9 years ago
It looks okay. I'd go for an i3 as my first printer as they're the most commonly available. But some kits are easy to build and work, some not so much.by DjDemonD - General
Re: Arduino stops uploading for no reason - 9 years ago
I get checksum errors uploading to either of my mega boards if I use the USB mouse whilst the upload is in progress. Leave the mouse alone and it uploads fine.by DjDemonD - Delta Machines
Re: Object 30 Pro - 9 years ago
That's a stratasys printer so it should produce excellent prints very reliably, but at a cost of £16000-£30000 you'd expect it to.by DjDemonD - General
Re: First layer modifier % - 9 years ago
Depends on you nozzle size and what layer height you're trying to print at. A 0.4mm nozzle set to print an object at 0.2mm layer height can give you a 200% thicker first layer which should help you to get it to stick. But I usually use 150% as you can't print 200% with a 0.4 nozzle and 0.3mm layer height as 200% of 0.3mm is 0.6mm which is wider than your nozzle. Your choice of layer height deby DjDemonD - General
Re: Leveled Bed >> Auto-Leveling Probe - 9 years ago
This is a choice, npn is easier to setup but if the sensor fails you'll get a head crash as the signal never appears when the bed is near the sensor and the standard open voltage 0v stays at 0v. Some sensors of this type will work on 5v so you can connect it to your endstop pins on ramps directly. The sensing distance is reduced and the triggered led might not work but its very easy. With pnp tby DjDemonD - General
Re: Worthwhile and cheap fire safety device. - 9 years ago
Seems like a worthwhile addition and its definitely worth testing, but I agree with James it might be difficult to get it high enough to trigger and then drop its fire retardant onto the fire especially if it is at the hot end which might physically be in many positions. Would work over the electronics assuming they are not enclosed.by DjDemonD - Safety & Best Practices
Re: Cleaning the hot end on the fly - 9 years ago
Don't know about retraction for cleaning purposes, but my only tip for filament removal with all metal hot ends is extrude an amount say 20mm then the moment it stops manually pull the filament briskly out so that it doesn't get chance to cool and 'bond' to the heatbreak throat on the way out. Has anyone implemented a cleaning area for the nozzle to move to to effectively wipe itself before moviby DjDemonD - Safety & Best Practices
Re: Delta homing issues - 9 years ago
The reply above seems to be accurate and sage advice. There is sometimes weirdness though, yesterday on my Kossel Mini only two of the carriage motors would move, the y motor did nothing. So I assume its a stepper driver and swap two over to test this theory but still the same. So I assume its a bad motor, swap this over and it works normally. Now totally confused I put it all back together exactby DjDemonD - Delta Machines
Re: Auto-Leveling + Z-Axis-Leveling [Prusa i3] - 9 years ago
As for the two z motors they could be independently controlled to effect a degree of x axis bed tilt correction but this would require quite a bit of firmware change and does nothing for y tilt. I feel it's best to have one z motor perhaps larger or geared and pulleys and belts to drive the two z screws. If you set both left and right square to the bed then tighten the pulleys on they should stayby DjDemonD - Reprappers
Re: Auto-Leveling + Z-Axis-Leveling [Prusa i3] - 9 years ago
When I get time to print it, I've designed an x carriage for the i3 with a hinge, spring and microswitch to act as z min probe using the nozzle. If the repeatability of it is good and the nozzle clean, it should give more useful bed levelling as it's nozzle based so no offsets etc.. Will keep you posted and publish stls if it works.by DjDemonD - Reprappers
Re: Idea: A RepRap Hanging From the Ceiling - 9 years ago
That's excellent, very impressed.by DjDemonD - Delta Machines
Re: Need help extruder jamming - 9 years ago
I've had extruder failures (mainly with PLA) from: - breakdown of PTFE linings within the hot end - too much retraction pulling hot filament too far up the heat break -filament grinding through at the drive gear/hobbed bolt sometimes from too tight (low) first, layers meaning the filament flow is restricted at the nozzle. -insufficient hot end temperature for a given filament -excessive hot end tby DjDemonD - Delta Machines
Re: I want: micro stepper motors for bed levelling - 9 years ago
Quotewaitaki Yeah, good post DD! I don't really understand why people give up with normal bed leveling and switch to auto bed leveling. Its an education problem. My first printer (i3) was ready made, built by someone else (badly) and I had no idea how to level the bed properly, it had no bed levelling screws, the heatbed was bolted direct to the y-carriage. I started inserting washers at one coby DjDemonD - Mechanics
Re: How to use G29 on a Delta? - 9 years ago
I'd suggest some type of z probe and an autocalibration firmware. I use Rich Cattell's marlin. Once done just add g28,then g29 to your start G code (I also add a heat extruder without waiting and heat to just below the temperature at which my filament begins to ooze to save time, it heats whilst it does the auto level.)by DjDemonD - Delta Machines
Re: Exceed print area - 9 years ago
It can't print itself 100% generally the frame is wood, acrylic or probably the best - metal. The electronics and cabling, hot end, motors, bed are all bought or salvaged from other (discarded) devices. Printing parts larger than the bed is handled by designing them to fit together after printing. This is not that easy or automatic. Keep doing your research.by DjDemonD - General