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Everything about Marlin firmware : Discussions, questions, support and feature requests...
LV8729 motor current setting - 2 years ago
I am getting strange results setting up a motor driver for my printer head changing mechanism. I am using a LV8729 and am driving a NEMA11 which has an Imax 0f 0.67A. I understand from the data sheet and other sources that IOUT = ( Current setting reference voltage / 5 ) / 0.22Ω. For 0.5A the setting should be 0.55V but this won't even move the motors. Increasing the trimmer voltage to 0.91V theby leadinglights - Stepper Motors, Servo Motors, DC Motors
Re: Heated Chamber Advice - 2 years ago
Silicone is very flexible and works up to about 230°C. Use the thick-walled variety often called "Vacuum Tubing". You can see examples of this in use in the following videos. (at about 15:45 ) and Mikeby leadinglights - General
Re: Revived a Dremel 3D20... Duet 2 Wifi, PanelDue, kinematic bed, hot swap PCB - 2 years ago
QuoteMKSA Quoteleadinglights As far as I can see, your kinematic mount should work satisfactorily although you may find unwanted behavior with heating or cooling of the build stage.... Mike No, it doesn't. Hmmm, you may be right or you may be wrong. When I looked at the video from doublec4 I saw a Kelvin kinematic mount with tension springs to maintain a seating force. Within the constraintsby leadinglights - General
Re: Precision Piezo Z-probe Now available. - 2 years ago
The 27mm diameter ones are 7BB-27-4LO while the 20mm ones are 7BB-20-6LO. The LO at the end signifies that they have leads attached. It is probably better NOT to try to solder on leads yourself as this needs a special low temperature alloy. Mikeby leadinglights - General
Re: Precision Piezo Z-probe Now available. - 2 years ago
Piezo disks should give a useable output up to about 80°C although some "no-name" piezos have not been too good. Murata piezos are more reliable. A pdf on shows the effect of temperature (about page 7 I think), time and multiple probe strikes on a disk. Your mileage may vary, this development after all, and many boojums wait to jump on the unwary. Mikeby leadinglights - General
Re: Revived a Dremel 3D20... Duet 2 Wifi, PanelDue, kinematic bed, hot swap PCB - 2 years ago
As far as I can see, your kinematic mount should work satisfactorily although you may find unwanted behavior with heating or cooling of the build stage. This is caused by slip-stick friction as the bed expands or contracts. On my printer, I used Maxwell type kinematic mounts and found the middle of the bed could rise and fall by up to 50 microns. Picture below of one of the three mounts with anby leadinglights - General
Re: Biceps, a two headed 3D printer - 2 years ago
The next bit of work on this printer is to try out the water cooling in printing conditions. I have already established that quite a bit of heat that the cold-end will be required to remove comes from hot filament being moved into the cold-end during retractions ( ). As far as how much, checking this by manually extending and retracting filament gives a not very precise value of "quite a bit". Tby leadinglights - General New Machines Topics
Re: My 6 input (5+1) mixing hot end - 2 years ago
Thanks, deckingman, it looks like I will be following you on YouTube from now on. I always find your progress inspiring and it is nice to see how well your printer is coming on - but also good to see that I am not the only entertainment that the gods of adversity have. A couple of thoughts from your video: I have started to move to Torx stainless steel screws as I am also getting too many roundeby leadinglights - Developers
Thermocouple hotend sensor question - 2 years ago
Is there an existing configuration of Marlin which would support two thermocouples with Adafruit AD8595 conditioners? The output from these is 5mv/°C with a -1.25V offset. Mikeby leadinglights - Firmware - Marlin
Re: Water Cooled Cold End tests - 2 years ago
I have done some preliminary tests by manually (software not set up yet) feeding PLA through the hotend, retracting the filament by 20mm then extending and feeding a couple of millimeters - repeating this approximately every 2 to 3 seconds for a minute. The temperature increase I read on the cold-end was about 0.7°C Without the filament it looks like the cold-end is extracting somewhere around 3by leadinglights - Tech-Talk
Water Cooled Cold End tests - 2 years ago
The first time I saw watercooling discussed on this forum the poster had soldered a straight bit of brass tubing at 90° to the stainless steel feed tube just above the heat break so that the cooling tube was touching at only one place. That user reported that it worked well. A more recent forum entry had somebody enclose the fins of an E3D V6 All-Metal hotend in a water jacket - a task that had tby leadinglights - Tech-Talk
Re: Two probes, Underbed for Z height and Z carriage mounted probe for leveling - 2 years ago
@Mr_Huns, Thank you for your interest. The piezo sensor work is coming on well-ish insofar as it has not given me any unpleasant surprises. The sensor shown in that earlier photo can be seen installed on the Z carriage in I wish the rest of it was coming on as well as I seem to be fighting the twin demons of leaks and airlocks on the water cooling. I have just sidled silently away as it seems toby leadinglights - Tech-Talk
Re: Precision Piezo Z-probe Now available. - 2 years ago
Piezos are inherently very sensitive and this means that they can pick up movement that is not what is being looked for. The most noticeable example of this is that the end of a X, Y or XY movement will result in shaking of the printer which can last for several hundred milliseconds - this movement will be picked up by the piezo and, if it is above the trip point, will result in a false signal. Tby leadinglights - General
Re: Biceps, a two headed 3D printer - 2 years ago
The present stage of the project is to determine how good the water cooling is. When I first started this project I designed a water cooled cold-end and did some simple trials to assure myself that it was satisfactory. The notes having been lost I think that a bit more disciplined approach worthwhile. The diagram below shows one of my water cooled cold-ends. The aluminium body has bee ghosted tby leadinglights - General New Machines Topics
Re: Biceps, a two headed 3D printer - 2 years ago
The last couple of days has been spent sorting out the wiring and making sure the documentation is up to date. The RAMPS 1.4 is getting a bit crowded in its housing and will be fitting homemade oversized heatsinks to get the heat from the motor drivers where the fans can cool them Something I didn't think of untill I thought "where are the Pololus?" Connection diagram to show what the RAMPS isby leadinglights - General New Machines Topics
Re: Connectors for HotEnd. - 2 years ago
Molex Microfit 3 are my goto for this They are rated at 10.5A so should be good for any normal hotend. JST make a 2.5mm in cable connector which is good for about 3A - still fine if you are using a 24V hotend Both of the above have shells that can be clipped into a bulkhead. Another option is the 10A connectors use by RC model aircraft to connect the battery to a brushless motor driver - these hby leadinglights - General
Re: Biceps, a two headed 3D printer - 2 years ago
Biceps is beginning to emerge from nearly a year in the wilderness. This was partly because I came across a problem with the design of the underbed sensors which needed several months of head-scratching. Besides this though, there was at least a degree of concern that documenting my build may be shouting into the wilderness with my words only read by netcrawling bots or the occasional dyslexic Goby leadinglights - General New Machines Topics
Re: Thingiverse taking it's last breath? - 2 years ago
I have received about 12 "comments" in the last few days all of which are essentially:- QuoteI want chat with a guy because I'm very lonely. Write me here please and I`ll give you my phone number.............................................. All of them are from the same poster, Sosatel3D. Although they are taken down as soon as I flag them, what I want to know is why they didn't remove the poby leadinglights - General
Re: Computer Motherboard - 2 years ago
With the most modern technology it is often a lot like magic - a brief typed, or spoken command, or one selected with a mouse click and magic happens. Few people have any idea of what is happening to make the magic: Even fewer have this knowledge if you exclude those who were alive and active when the magic was being developed. It is no good though for me (or us*) to get smug about our deep undeby leadinglights - General
Re: Computer Motherboard - 2 years ago
Like Roberts_Clif I used a SWTPC; but in my case it was a 6809 running Flex - later replaced by Uni-Flex then a Unix knock off called Quix - all on 96 Kilobytes (not Megabytes or Gigabytes) of RAM. This was in the very early 1980s. Back in those days an elderly (elderlier than I am now) technician used to re-filament and rebuild radio valves from the 1920 and 1930s as a hobby. When asked why heby leadinglights - General
Re: Heatsink pastes for hotends - 2 years ago
Quotethe_digital_dentist .................. Is your extruder having some sort of problem? I am not having any problems yet, but if I use a wirewound resistor rated at 3 Watts in air and ask it to dissipate up to 32 watts I have to be sure that the heat will get away - or I will have problems. Early trials showed that it will, but now the resistor body size has changed and most thermal compoundsby leadinglights - General
Re: Heatsink pastes for hotends - 2 years ago
I have found 3 of the original 5 dummy hotend blocks that I used some years ago to do the failure test. I think I will try a repeat of the earlier test with different compounds - with and without copper shims to fill the gap. Machining new blocks to fit the resistors would be a pain - and wouldn't guarantee that the next batch would have the same diameter. Mikeby leadinglights - General
Re: Heatsink pastes for hotends - 2 years ago
The hotend is my own design but uses a vitreous enamel wirewound resistor instead of a heater cartridge. The reason for this is that I was an early adopter of heater cartridges but they let me down badly - I have never had a WW resistor fail. Part of the problem here is that this design uses a very small resistor which is over-run to the wazoo and beyond: The element wire temperature gets to 420by leadinglights - General
Heatsink pastes for hotends - 2 years ago
Has anybody used pyrolytic graphite based heatsink compounds on their hot-end heaters? Arctic MX-4 is an example of such a compound but they offer no data on maximum temperatures. The significance of this question is that I have used such a compound that I acquired when it was banned by a health and safety officer due to the lack of a material hazards datasheet. This compound had a thermal conduby leadinglights - General
Re: Filament measuring thingy - 2 years ago
When I looked for PAT9125 the first thing I came across was a PR (pull request) on Github from the Prusa team . Some interesting stuff there. Between the Prusa and Duet laser sensors and the simpler wheel sensors, I think this field is pretty well covered so I will use my efforts elsewhere. Mikeby leadinglights - General
Re: Filament measuring thingy - 2 years ago
@ECJ I am intrigued by the "Prusa" sensor that you linked to at as I can't understand out how it detects movement in what must be a very short path length. I am moderately sure that I can detect movement including direction and speed by monitoring the movement of a texture on the surface of the filament. My problem is that any practical way I can find to do that needs a decent optical path, notby leadinglights - General
Re: Thingiverse taking it's last breath? - 2 years ago
QuoteThingiverseAfter scheduled maintenance yesterday, Thingiverse is experiencing issues with search. Our engineers are investigating now. Please try again later. The engineers have obviously tried Ctrl-Alt-Del dozens of times and even tried switching it off and on again I think it is just not a priority - and maybe never will be again Mikeby leadinglights - General
Re: Filament measuring thingy - 2 years ago
QuoteECJ ......................................................... As for the filament presence sensors, I believe that the most useful are those that are also capable of detecting movement, because if something occurs that obstructs the movement, the simplest sensors become useless. I believe that the work of creating a new sensor using capacitance detection would only be justified if it could aby leadinglights - General
Re: Patents - 2 years ago
If a member of this community comes up with an idea that transforms 3D printing for the better and then successfully keeps it from the capitalists of the western world and the cloners of the Orient then it would never be made and will not transform 3D printing. The RepRap world may have been different in the past, but how many now make their own 3D printer? How many make their own extruder? Doesby leadinglights - General
Re: Filament measuring thingy - 2 years ago
@ECJ I think you are right on all counts although there is still a possible place where the capacitative sensor could be used. Humidity will vary between the outer layers of a roll and the inside. The layers most exposed to the most recent humidity will reflect that. Filament quality when I made my first printer in 2011 was pretty awful but I don't think I have seen a thickness problem in severaby leadinglights - General