Unipolar 3D printer part 12 - endstops and wiring!
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- čas přidán 8. 09. 2024
- One of the last things I need to do on my super budget DIY 3D printer is installing limit switches, adding a part cooling fan and running all the wires to where the controller board is going to sit! Along the way I also ended up covering the basics of unipolar to bipolar stepper motor conversion and introducing the lost art of cable lacing. Next episode we're installing the Arduino Mega and building a custom shield to manage those five seperate voltage levels!
Link to the schematic for the endstops:
reprap.org/wik...
Here's some affiliate links* to parts I got for this printer:
5pcs A4988 stepper motor drivers: s.click.aliexp...
Cheapy hotend kit: s.click.aliexp...
Arduino mega 2560: s.click.aliexp...
Geeetech PLA filament: s.click.aliexp...
4010 turbine fan: s.click.aliexp...
100k NTC temperature sensor for heated bed: s.click.aliexp...
10m nylon coated fishing line: s.click.aliexp...
Keep in mind I got a few of these items during sale, so the total might well be above $50 now (especially with inflation)
* if you decide to purchase something through an affiliate link I may receive a small commission at no additional cost to you :)
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21:03 brother, that works. nothing wrong with that. your content is alot of fun. good job!
the thing about having 300km of cables and yet not finding the one you need it's the most relatable experience we share hahaha love this project!!
True hand craftsmanship ! Thanks
I LOVE the cable lacing!
Little context I forgot to include since I already covered it in a previous episode, but in case you haven't watched it: Z-axis and extruder remain unipolar using my custom driver, but the X & Y-axes were wired up as bipolar allowing me to use the A4988.
I actually really love how is this project turning out. I'm in the process of building my own from scratch and I actually learnt a lot watching your woodworking. I'm a computer engineer but I'm pretty bad at mechanical engineering, so this has been very refreshing and It has helped myself to solve some issues I faced. So keep it up with the nice work, I'm enjoying this a lot :)
As a matter of giving some advice I might find useful, if your v6 clone is clogging while printing, adding a bit of thermal paste to the part of the heatbreak that goes screwed into the heatsink (as in the official documentatio & installation videos) it helps with thermal dissipation and avoiding clogs. It helped me quite a lot because I usually use cheap v6 for my builds.
Bowden is not worse than direct drive, in your case you might even benefit from it, since the x carriage will have less mass.
Also, as you are into recycilng, I think you will love recycling bottles into filament. I spent the last 4 months trying to recycling some with some success, and the end result is quite satisfying. Improving the machine I have is one of my future projects, because the one I have currently is quite frustrating to use.
Cool, I'm absolutely horrible at software stuff!
Thanks for the advice with the hotend, I figured this cheap clone might be pretty awful given I've never seen anyone use those anywhere before.
I'll definitely recycle bottles, it's been on my list since starting this project, tho I'll do it slightly different to the way it's usually shown online to hopefully get higher filament consistency.
@@ChronicMechatronic well, just ensure that is assembled correctly and you will be fine :) actually, since it's all an open source standard, you could even make the parts yourself. I don't think it will be awful though. The first time I bought an original one, and then bought some good quality clones and the difference is close to none. Bad clones are a lottery.
The part that made the most nervous about pet recyling was that the disgusting gunk they add to the stick the label, that thing is a nightmare to take out and it gets everywhere (depends on the brand of the bottle though), I'm also investigating how to do it differently.
Yeah haven't thought about how to deal with the label glue yet, I wonder what they do in recycling facilities? after all they can't wash all the plastic in agressive solvants... Probably will end up just cutting out the piece with the glue, usually it's just a little rectangle after all
No idea, people usually are able to clean it while heating it, but for me it was a nightmare. That thing got everywhere and was imposible to clean without spending hours.
The lever on the endstop switched is just there to make it easier for button to be pressed.
I think there are more reasons but when making my diy cnc the lever on the limit switches was pretty handy to both give myself a bit of extra space when getting closer to the frame (to avoid breaking everything up), it also gives an easier alignment to make sure the part will press the switch and makes it way easier to use it sideways were the carriage does not bump against the switch itself but goes in front of it engaging the lever, to make such a thing with that miniscule button would be a really hard feat
True that makes sense, they were often used against cams back in the day
The initial knot is also used for basic construction, is a very good at attaching to sticks and logs
The reason for the little levers on the mircoswitches is a) to make them _less_ precise, so easier to actuate, and b) to limit the force on the actual switch and increase lifetime.
Interesting, tho how would it limit stress in the actual switch when the lever pushes it at an angle and my carriage pushes it dead straight?
@@ChronicMechatronic the lever bends, therefore limiting the force on the switch.
@@polygorg ah that's why they're so flimsy 😅
For the angle bracket I'd add some extra holes and screw the fan in, adhesives over a heated build-plate surface and all.
The lever on those switches usually helps create a springy buffer, it's harder to over-press and destroy the switch, having a shorter throw does indeed increase the accuracy, but, you have to not destroy the switch via impacts to maintain accuracy as well!
Also I don't think headphone wire is a good choice, if the enameled insulation gives out from gantry motion, that's a PSU voltage to ground inside the wiring itself?
Ah yes, hadn't thought about heat destroying the double sided tape, I don't think it should be an issue tho because the fan will cool it's housing from the inside...
Makes sense with the switches, let's see how long it takes me to destroy them 😂
Yeah the headphone wires are a bit crappy, I've never seen any short out tho even though they always tend to break - it'll be the Atmega 5V to ground in that case, so I included a polyfuse on the shield to be safe :)
some folks use old t-shirts as rags... there i am using holy underwear to wipe the dust from my solar panels. waste nothing lol loving the progress you have been making man. wont be much longer we are gonna see this thing in action :)
Maybe consider programming a PWM pin in your microcontroller to adjust the speed of your driver motor fan. You could get really fancy with linking the fan speed to the movement of the stepper motor or put a thermistor on it (would need to program another pin on the microcontroller). Anyhoo... This is a great project and made me a subscriber. I'm looking forward to seeing how it all comes together.
Yea I went through all those options compiling Marlin yesterday to try and familiarize myself with it, and was totally overwhelmed 😅 I think I'll stick with the simple options for the time being until I stop being the total 3D printing noob I currently am 🤣
It is a lot to learn. I've been doing it for years and am still learning. If you're not familiar with programming microcontrollers, you should look into learning arduino. It uses the same programming language that Marlin uses, C++. Lots of info on CZcams on how to program with it. If you can build a 3d printer from scraps, you can learn C++. Cheers@@ChronicMechatronic
Awesome!👍
If you change the spool holder, I think it would be a good idea to leave out the bearings. It looks to me like it can turn too easily, leading to the windings coming loose which can lead to annoying tangles later on. This not happening is something to pay attention to in general. I have run 5kg rolls on an old pipe just fine. I'm not sure your little motor could pull that, but I think 1kg shouldn't be a problem, at least as long as the rod is sufficiently smooth. You should of course decide based on your extruders observed power.
Thanks for mentioning! I think I once heard about tangling being an issue but totally forgot about it again! It's true, my extruder is quite limited in terms of power, it even has a hard time pushing the filament through the full length bowden tube at higher speeds, hence why I thought bearings would be great so it doesn't also have to struggle with unrolling the spool.
@@ChronicMechatronic If it has enough a bit of resistance in the bearings it should be fine. Even if the bearings are very good, the contact between the spool holder and the spool should be fine. Don't take my word for it tho lol
11:00 those byj28 motors . i have a friend that uses 12v on them for a long time. Apparently thru can handle it. I use 6v no problem.
Unipolar or converted to bipolar?
In bipolar mode you can run them on pretty much any voltage you like since the driver limits the current (of course it needs to be set to the same current the motor would naturally consume at 5 volts, or less)
With a ULN2003 I wouldn't go much over 5V as they do get quite hot already
@@ChronicMechatronic he used the uln chip and yes they were really hot . he ran them for Halloween cables pulling ghosts.
@@TheRainHarvester huh, wow.
@@ChronicMechatronic you might get extra torque speed if you increase the voltage. No warranties though...you might free the magic smoke!
pfte tube looks quite long, could end up leading to print quality issues. On my printer of this style I mounted my extruder to the top right of the frame and the tube is probably about half the length this way. I even feed the filament from the left side of the extruder (top middle of the frame) into the right side of it using a reverse bowden to keep the transition smooth
Yeah I will switch to direct drive and reverse bowden when I do the lead screws. For the time being I don't really expect great print quality anyway, given the 0.1 mm resolution.
Why haven't you cut down the bowden tube? Not doing so may cause the extruder to skip steps due to higher amounts of friction and increase stringing.
Because it needs to be this long, I said so in the beginning
@@ChronicMechatronic oh alr
10/10
keep going
12:49 but i heard that stepper motors have more torque while microstepping as both coils get energised while microstepping rather than one..
No that's when you wire a unipolar motor as bipolar using the entire center tapped winding. With microstepping one coil gets energized to pull the shaft forward while the other one pulls it back, resulting in a 'virtual' step in between the two positions. The holding torque (and any torque) on those is a lot lower since it can't rely as much on the direct transfer of magnetic flux through the steel cores of the windings (I may be talking out of my ass on that last one, but in any case the torque is lower)
Bro! I’m the same way about reusing little things lol
Please please run this thing with Skeinforge when you get it running. And then print parts for a Prusa Mendel.
I'm afraid Skeinforge goes way over my head, I'm a bloody beginner at 3D printing 😂 I'll use Repetier to control it for the time being
you should try a delta printer
Which hpgl firmware version are you using ?thanks.
Stock Marlin
reverse bowden ftw.
thats not reverse bowden
@@rubenstenlund I think he meant the future reverse bowden when I switch to direct drive
@@ChronicMechatronic yup!
Cable management is important, or else it will look like a server room, also 5 power supplys?!?
Yes, 5 power supplies 😂 more about it in the next episode
Why didn't you turn unipolar motor into bibolar motor my English is a bit bad sorry 😅
Hey! I just stumbled across your channel. It's really impressive. If you are in need of any 3D printed parts, let me know. I don't know how shipping would go from europe, but I would be more then happy to send you smaller parts like pulleys and gears to help you with this project.
That's really nice of you, but I think I'll get by! Actually I'm in Europe too, so it wouldn't even be a problem :)
4:15 what is the heat gun for? And why isn't it melting the wire insulation?
Heat shrink tubing 🤷
Oh i realizedit was transparent. Never saw that before!
I belive he's using a heat shrinking for the joints
@@TheRainHarvester I guess I should have chosen color, never thought about the transparent one not being very visible on small screens 😅
15:44 what keeps the knots from sliding together in one spot on the cable?
Excellent video! I'm book marking it for cable management!
Just friction, if all the knots are tight there's nowhere they can go. Also, since the string runs along the cables both ends are perpendicular to the way they'd naturally come out of the knot which kind of locks things up
I uploaded the cable lacing section as a dedicated video on my shorts channel, in case you'd rather bookmark the dedicated video and not have to scroll through this monstrosity to find the spot: czcams.com/video/ZrwzC1_asQY/video.html
@@ChronicMechatronic oh just saw your friction comment. I asked the same on the shorter video. But I'll leave the question there too for info/algorithm. 😃
@@TheRainHarvester haha thanks!
I also have a 12 volt 360 watt smps..but it's output is not stable sometimes it is 15 volt sometimes it's 19 volts...I wonder how can i fix it... It's inbuilt potentiometer also doesn't work..(i picked it up from a scrapyard shop)😅
Aah, the most common components to fail I've encountered so far are capacitors and the rectifier diode at the output (the diode was actually what had killed the 24v supply I'm now using, after replacing it everything was fine) tho I doubt those will be the problem on yours. I also have a big triple voltage supply from an old monitor which should put out 5.5A @ 24 volts, but whenever I try to draw power the voltage drops to just ~10V 😂
I have yet to find out what's wrong with it
@@ChronicMechatronic well i also have a 24 volt one which i salvaged from a photocopy machine..It also have a sperate 5 volt supply but after couple of short circuits it's doesn't work anymore 🙃
Subscribed!
I will watsch your career with great interest! :D
hello
I really appreciate your work, but I have a question. Ok, you're making this printer for a pretty cheap price, but even your project start date is pretty old, is it worth the effort? What I'm trying to say is that in the time you spend on this, maybe you can make money by pulling the electrical wiring of a house and with that money you can buy a nice printer. I wish you continued success and hope you come to better places.
Yeah a lot of this seems like saving money and not buying stuff just for the sake of it. It is easy enough to find cheap second hand bipolar stepper motors and 3D printers. The best option would be to just take parts from a second hand or broken 3D printer, or even just to buy a reprap or CNC shield for an arduino.
Yeah for anyone other than maybe a teenager too young to legally work it doesn't make any sense of course 😂
But I really like reusing stuff that would otherwise go to waste, even if it's not quite as suited, plus it makes for a great challenge and nice content! Originally my only goal with this series was to have the videos make back the money I spent on the project (at that time one video only made ~$1)
As they say, "the journey is the destination" and we get to learn a lot in the process!
@@conorstewart2214 spot on, otherwise what would be the fun of it? 😂
@@ChronicMechatronic Ok, you are right, it may be true for someone who cannot work legally, but someone at such a young age cannot use the woodworking machines you use, but can buy ready-made parts and assemble them. :D
Of course, I can't say anything if you like to push yourself in this way :D but one of the important condition of engineering is time. You can buy a sigma iron profile and simply assemble the case within 1 day.
But again, as I said, if you like to do it this way, I can't say anything. I couldn't do a job like this in my life.😅
too true, I hadn't thought about the machinery 😂
The "time's money" mentality is actually what puts me off pursuing engineering professionally - like, as soon as solutions get compromised over saving time the fun's over for me. Much of my engineering may not really have a place in this fast-paced world but it's very educational at the least and serves a novel niche that hopefully has future on this platform. I feel like it's the best I can contribute to society as a wole really, because spending the day squishing dough in a bakery didn't turn out to provide the fulfilling life I hoped it would after all.
Maybe you should keep the first printer and use it to make a new printer from scratch, rather than completely dismantling and rebuilding it
I will eventually, but first I need to get this one working well enough, I doubt the 0.1 mm resolution I'm currently getting is enough to print usable parts 😂 and when I go to the length of installing lead screws I might as well relocate the extruder...
Hi Ben! Cute endstops... Exotic but effective cable lacing, consistent with smart recycling of course. Useful post for people who don't know that wiring cables is an important part of prototyping. Btw I found a guy who designs his own heat bed. Interesting czcams.com/video/5CeCxkFVCdM/video.htmlsi=HZMKnzWsxxiGJY7Z&t=396 Have a great week Ben! Can't wait the very first print.
Coincidently i just found some zip ties randomly at a crosswalk here in the city where homeless people leave junk at. Here we take zip ties for granted even the poorest will toss them away, while zip tie starved children overseas are cutting theirs for re-use.... makes me sick to my stomach. Nah jk thats a good tip though never thought of it. Id like to see what kind of printer you could make if cost wasnt an object because you have some unique out of the box ideas.
Good one lol!
I don't know if I would even make a printer if cost wasn't an issue, I'm really not that into in 3D printing in general. The cost saving aspect is really what makes it interesting to me, so rest assured this will not be my only 3D printer 😁
I have some very interesting future uses for CNC technology in mind that I can't wait to explore, though I still have a lot to learn beforehand 😅