You should always use a granite surface plate desk, even in the kitchen! I sleep on a granite surface plate to make sure I get the most precise dreams ever, to within 3 microns.
@@reps EVERYTHING IS CROOKED! REALITY IS POISON! *LAMBS TO THE COSMIC SLAUGHTER*! I've seen that scene at least 5 times this week because it keeps popping up in UA-cam for me.
Hey Marco, the Steinmeyer ball screws are induction hardened as well (only the threads up to a few mm depth into the material). They also start as rolled part but then they get precision ground to fit to the pitch within tolerance (as low as a few µm). Of course the abrasive grinding will heat up the thread but they balance the cutting depth to control the soft-annealing. So no worries - they will hold up fine.
bearing blocks on linear rails must have a certain amount of preload to give you accuracy and rigidity under load. that's why a new linear blocks don't slide freely and have some amount of friction. (and that used rails from industrial machines slides freely just because they are WORN OUT and lost their preload. that's why they was removed and replaced with new ones)
Sounds all correct! The banggood ones however have an uneven friction and seem to get caught on some high spots. And since hobby stuff is the only area where you would consider used rails anyway I think even the most worn-out ones will be easily good enough? Maybe I can find a way to actually measure my worn-out Rexroths ...
@@reps I've recently bought some used miniature Bosch rexroth linear guides (size 15, 4 bearings, 2x330mm rails) from ebay, alongside 500 steel bearing balls. Had to replace the old balls and even replaced the new ones multiple times until I found a "good batch" of those cheap balls that were running smoothly with slight preload. All in all this costs me 120€ compared to new ones from Bosch for over 500€
@@michaelkelly3158 the original Bosch rails are very similar to hiwin rails. You'd have to compare lifetime, friction or other technical properties in a specific use case. Just saying "these are better" is impossible. As long as you get new brand name rails (hiwin, Bosch, SKF, Schneeberger,...) you should be good to go for any hobby project.
I have some cheap Chinese linear rails in a 20mm size. They run kind of rough but don't seem like it's specific high spots. Do you think taking them apart and cleaning would help smooth out the motion? I kind of suspect it's small particles in side the carriages are causing it to stick
@@operator8014 Your in luck I happen to be in charge of the cnc department of Infinity Drain. We have brand new AMS Loader from Amada paired to our 4kw Laser. The Loader uses just that to tell where the pallet traverser is and to also measure sheet material thickness.
@@operator8014 already done. We use those at my work. Picometer accuracy. It's a pain though, as in Australia this accuracy encoder systems requires defence approval. We had one system fail, and I had to arrange approval from ministry of defence to be able to send it back to the manufacturer for repair.
@@brianjensen5200 Does everything run in a temperature controlled oil bath? I saw a video from Mitutoyo and that's how they keep their master leadscrew at a fixed temperature when screw cutting.
@@evildrome no our motion stages are in free air. We keep the technical hall under 1K temperature deviation and encoder feedback loop controls the rest
I know it's been a while but at my job we have what is essentially a large pair of calipers to calibrate cinema cameras. In order to discover and correct for long distance accuracy we use the distance traveled and revolutions of the motor. It uses a belt and pulley along with a very nice absolute encoder. We note the error (difference) of where it ended up vs the target and use the encoder resolution as well as the revolutions of the pulley. So if the machine was 0.015" off we would use that distance multiplied by the ticks/mm of the encoder (a constant), divided by the number of revolutions made during the move. This would give us a long range error correction value that the machine can compensate with. Essentially the number of encoder ticks it should increase or decrease by with every revolution of the pulley. I believe a similar calibration technique could be used with a ball screw mechanism.
6:04 When a ballscrew shaft is ground, the metal can already be very hard prior to grinding and the resulting screw can be far superior than a ballscrew that gets some hardening in its roll forming process.
Depends a lot on the application, but most companies will replace ball screws when it starts causing problems. If it's in a machine that NEEDS to run without a hitch, consumables will generally get replaced or at least checked for wear on a predetermined schedule. I used to work for a company that would always have a maintenance crew scheduled for holidays so they could do that sort of thing without creating excessive downtime.
The standard operating procedure in North America is: A more and more frequent motor overload error, operators get frustrated enough to complain, so maintenance come and grease it, same thing happens a few more times, maintenance get frustrated with greasing it every damn shift, and then they tear it open to find out it’s completely fucked, ball bearings all over the inside of the machine, parts are ordered in a hurry, often resorting to physically sending a guy to the distributor to get the parts faster, because the line is completely down and hemorrhaging money. You guys have a better system in Germany?
Here in Vietnam we can get those linear rail and ball screw second hand for dirt cheap. They are often disassembled from old machines. Just got a pair of unused IKO LWA15 rails and NSK 1602 ball screw for like $40. $200 can get you a nice 400w servo with driver from Japanese brand like Yakaswa.
I'm working with high precision CNC mills and we use 30mm diameter ballscrews with 16mm pitch. But the bearing blocks are something different. They cost around 1500€/piece and weight around 6-8kg I think. But we use much more beefier motors. 2.2kW per ballscrew. That crackling noise in that nut hurted very badly.
I think it's important to note that the final hardening comes just before grinding (which happens after rolling in the case of rolled ball screws) and so the effect of surface hardening is minimal compared to the higher precision and therefore tolerances of purely ground ball screws.
Always interesting ! In my experience, too much precision is useless, because, at the end, the total deflexion of the structure, leadscrews, the motor head, the tool, etc. is very significant, but, of course, "too much precision" is better than "meh!". I'm saving money for the parts of my next CNC router. Thanks for sharing !
FYI: You should look into Klipper if you are interested in interfacing a regular threaded OS with a realtime OS. Klipper is a 3d printer software that does all the heavy lifting on a computer (usually a Pi) and then uses one or more microcontrollers to schedule and execute commands.
@@reps I honestly think it's the way forward for 3d printing as opposed to using STM32 based boards with webUI addons like the Duet. Plus it can be infinitely scalable. Want to have two Y-axis gauntries with two X-axis carriages with two independent extruders each? Slap a few cheap reprap boards together and hook them up to a Pi and install Klipper on everything.
I know this is off topic, but what is your planned controller setup? I know you have some LinuxCNC experience, but have you looked at the MachineKit? It’s a pretty cool fork, far more modern in architecture and much more modular ecosystem. You can find out more at machinekit.io. I have no connection to the project, just believe that is superior and worth a look.
Finally, a new video!! I was getting really tired of watching reruns and can't seem to get my fix anywhere else! I just got my MK3 Extended last week and already started my collection of cheap Chinese knock-offs….I'm in too deep already and obsession/fascination with Micro Reps isn't going away..one video every couple months just won't suffice!
The qualifying test for becoming a marine artificer in the royal navy in the 1970s was to build a miniature metal lathe. By hand from scratch, to a maximum accuracy of so many thou. Apparently creating those jack screws and whatever they made to run along it is tricky.
Yep, turning the nut is tricky. It takes a while turning it back and forth to be ‘happy’ again. For a while it was trying to force out the plastic seal. At one end the plastic seal is held in by two tiny grub screws.
Edit: Gets addressed in the 'Shaft' video. Don't CNC machines usually control their travel using DRO? If built that way, the lead precision of a ball screw doesn't matter as much as the backlash. (I think "Umkehrspiel" called backlash in English.) Probably because the ball screw, because it is warmed by friction and cannot be protected as good, is much more susceptible to thermal expansion than a glass scale. Possible that a good controller even uses both to achieve sub micron positioning.
Your drift is likely caused by thermal expansion. You'll get about 10um/m change if your ball screw changes temperature by 1 degree. You can confirm this by heating the ball screw with your hand.
Nice to see some SMC stuff in the video. I have never used anything from them other than pneumatics but i got a tour around one factorie and they do make very high quality stuff....
A simple laser interferometer can be used to measure accuracy over long distances. All you have to do is to program maybe an arduino to count how many times the interference pattern cycles. The accuracy may not be great because you can't really properly calibrate it but it should be super precise, as long as you don't loose count.
Anxiety when using expensive ball screws? We use them in a foundry enviroment where there's sand everywhere, they trash out about once a year. Also, you know when linear guides are replaced? When the carriages explode from all the dirt and grease inside them and the rails look like an apprentice filed them out of one solid bar and got bored halfway through.
"These are the polar opposite to the Chinese ones" Aaaaand of course they are german. Germany, the place where a a simple thread can be overengineered so it's super expensive but still being worth it lol.
That's some quality hardware! I'm only worried a bit about this Z axis, it looks going to be 2-3 times longer than spacing between rails, this will amplify load on the rails, and then amplify deflection at the tip of an end mill even more. I might be overthinking it but i'd be tempted to make something like Okuma double column machining center.
I was just pooping and was searching for some video to watch on the meantime.. And then I saw that you uploaded a new video! That was the best poop I had this year, thank you!
Hello, it's my first comment here.. First of all love your channel...So I am writing aboute the "el chepo chinese linear rails" i've bought some more then a year ago.. Frustrated over the laggy performance, etc... Solution disassemble the carriage submerge in alcohol (to clean some wierd oils inside) reassemble, greas up... It worked for me... Still going strong after a year or so of modernet to heavy use..
What's the amount of the slow drift? Steel has a coefficient of linear expansion of ~10-12 microns/meter/degrees c, so temperature expansion vs the desk should certainly shown up on your micron scale.
I am also German but have been living in the US for over 40yrs. I am looking to build a reasonably priced desktop machine to route/mill parts for my hobby. Why is it that I am also obsessed with precision and worry about thermal expansion of materials? I guess it’s in my genes? 🤪
To measure long distances you could attach levers to the encoder. It's the same technique that people used back in the day to convert large movements into small ones for precise machining. You'd be trading micrometer precision for mm or cm precision though.
You might want to consider adding a DRO to your CNC machine. You can get them cheaply on ebay up to ~2m+ lengths and its probably easier to make the glass ruler in the DRO nearly perfect than it is to make a perfect ball screw. You could use the DRO for absolute position in a feedback loop with the servo motor.
For measuring longer travel accuracy, a fairly cheap method would be to get one of the cheap 12" (~240mm) digital calipers. Note that it has to be one of the cheap ones, but for some reason nearly all of the cheaper digital calipers have serial output, and there are tons of tutorials for interfacing with them. Resolution isn't spectacular (+-.05"), but they are much cheaper than something like a lathe bed axis DRO and would likely provide some good data (at least for repeatability testing). At least in the US, they are normally avaliable for ~15USD, I would imagine they aren't much different in the EU. Plus, then you don't have to feel bad about hacking a nice starrett or mitutoyo instrument!
Hallo Marco, Ich habe mir auch die BK20 gekauft auf aliexpress, und sehe da sind ganz normale lager verbaut. Denkst du das die irgendwie ok isnd für den konstanten axialen druck auf zwei seiten? Ich brauche es fuur meine Fräsmaschine (machinable area = 2440 x 1220). Mein setup hat zwei 2525 ball screw spindles für die lange Y achsee, und eine 1616 für die X Achse. Denkst du es würde sich lohnen gleich jetzt vor der montage um zu rüsten, oder erst mal schauen was die billigteile hergeben? Danke für einen Tip!
Hello Marco. At 3:38 you show us a voice coil similar in construction with voice coil from hard disk. Please explain me how it remain fixed on the position. On hard disk if you apply +and- the voice coil goes to the end. If you reverse polarity - and+ it goes to the oposite end. The question is what kind of electricity makes this voice coil to remain fixed on a track on any other position betwen right end and left end ? This is interesting to put an osciloscope on the voice coil on this device and show us how can be stand still with incredible acuracy. Nobody know to answer me this question for several years. Thank you.
I love ball screws, but everytime I see one my mind flashes back to the $500 Bosch-Rexroth paperweight on my desk resulting from the spindle spinning off the shaft and onto a dirty floor.
you can get away with using thinner screws by tensioning them slightly, either between 2 angular contact bearings (use roller ones, preloading is hard on bearings that are mostly stationary), or rigid and rotating the nut. I like the chasing micrometers, but harmonised stiffness, adequate stiffness and vibration dampening is where it's at with diy cnc methinks. still, i wouldn't say no to those Steinmeyers either:)
Less vibration since a long screw would flex while rotating. a nut that rotate around a static screw would not make the screw wobble. You could use thinner screw and improve over longer distance
At my old job they did replace them after operating hours. And yes this is done by a lot of companies as they said. It's cheaper to replace a rails + carriages before it fails rather than failing during a cnc job which will cost a lot more like failed material and downtime hours which can cost thousands of dollars.
@@Underp4ntz_Gaming_Channel It's also usually done when "you're already in there." If you've got a machine torn apart, and it's halfway to the replacement time, it's easier and cheaper to do it all at once.
If I pick a handful of UA-camrs about 3D printing (you being one) and I can get us all all in a conference call with video if possible so “talking with hands to help with visuals” will help. .... And in this live group call we form a “company/Organization” for my truly revolutionary design of a printer to be sold as a product. I’m not asking for money, I am a over the road semi truck driver, I make plenty of money for everything needed, I just don’t have the time to do anything other than talk really. And I live out of my Simi Truck. So I don’t have build space. Most of my design is set in stone, but there are multiple ways to do different factors of my design, can we all discuss it and maybe add tweaks to make it better. But what we all discuss as a collective does not leave the project and stays private until it is ready for sale, can we all agree on this and talk about
No matter how many times I watch one of your uber crack me up videos, I still get a great chuckle! Super dooper. Mike's Radio Repair and Davey Jones? at EEV BLOG have recently experienced the displeasure of thumbs down bots and comment bots. Would you consider making a video called "Das Bots"? I apologize in advance for the edginess of the idea, but if anyone can pull it off, you das man. If I have offended, please forgive me. The quality and expertise of your sharp wit is no laughing matter. I have nothing but respect for you. And much admiration. Thanks!
Tiny fpga? It's time that you discovered the Parallax Propeller. The new P2 is mind blowing. Any/all of its "smart pins" can decode quadrature signals at sys clock rate (180 to 300+ MHz) . Eight independent processors can be programmed in C/BASIC/FORTH/ASM and Python is on the way.
I'd recommend using a double ball set up not, a single.. take those plastic seals out & degrease the bearing balls and you'll find a good amount of play. The grease & plastic seals mask the ball screws axial play.
You should always use a granite surface plate desk, even in the kitchen! I sleep on a granite surface plate to make sure I get the most precise dreams ever, to within 3 microns.
< Insert Rick & Morty True Level Scene here >
It also straightens out the back
@@DeDeNoM ...Or make a "C" with your column, if you sleep over your side. Cheers !
@@DeDeNoM Raises hell with the "roids" tho!
@@reps EVERYTHING IS CROOKED! REALITY IS POISON! *LAMBS TO THE COSMIC SLAUGHTER*!
I've seen that scene at least 5 times this week because it keeps popping up in UA-cam for me.
Hey Marco, the Steinmeyer ball screws are induction hardened as well (only the threads up to a few mm depth into the material). They also start as rolled part but then they get precision ground to fit to the pitch within tolerance (as low as a few µm). Of course the abrasive grinding will heat up the thread but they balance the cutting depth to control the soft-annealing. So no worries - they will hold up fine.
bearing blocks on linear rails must have a certain amount of preload to give you accuracy and rigidity under load.
that's why a new linear blocks don't slide freely and have some amount of friction.
(and that used rails from industrial machines slides freely just because they are WORN OUT and lost their preload. that's why they was removed and replaced with new ones)
Sounds all correct! The banggood ones however have an uneven friction and seem to get caught on some high spots. And since hobby stuff is the only area where you would consider used rails anyway I think even the most worn-out ones will be easily good enough? Maybe I can find a way to actually measure my worn-out Rexroths ...
@@reps I've recently bought some used miniature Bosch rexroth linear guides (size 15, 4 bearings, 2x330mm rails) from ebay, alongside 500 steel bearing balls. Had to replace the old balls and even replaced the new ones multiple times until I found a "good batch" of those cheap balls that were running smoothly with slight preload. All in all this costs me 120€ compared to new ones from Bosch for over 500€
@@mariusb6035 How do these Bosch rails compare to Hiwin rails? Only ever heard of Hiwin rails being used in high end CNC applications.
@@michaelkelly3158 the original Bosch rails are very similar to hiwin rails. You'd have to compare lifetime, friction or other technical properties in a specific use case. Just saying "these are better" is impossible. As long as you get new brand name rails (hiwin, Bosch, SKF, Schneeberger,...) you should be good to go for any hobby project.
I have some cheap Chinese linear rails in a 20mm size. They run kind of rough but don't seem like it's specific high spots. Do you think taking them apart and cleaning would help smooth out the motion? I kind of suspect it's small particles in side the carriages are causing it to stick
That's going to be one hell of a PCB etcher
the worlds most expensive dickbutt plotter
Can’t wait to see the 1:100000 scale city that he etches.
When you go below 1um accuracy you start getting weird effects like the heat from your body causing thermal expansion.
I want to see someone use laser interferometry to measure the position to kick off the next generation of hyper accurate making.
@@operator8014 Your in luck I happen to be in charge of the cnc department of Infinity Drain. We have brand new AMS Loader from Amada paired to our 4kw Laser. The Loader uses just that to tell where the pallet traverser is and to also measure sheet material thickness.
@@operator8014 already done. We use those at my work. Picometer accuracy. It's a pain though, as in Australia this accuracy encoder systems requires defence approval. We had one system fail, and I had to arrange approval from ministry of defence to be able to send it back to the manufacturer for repair.
@@brianjensen5200 Does everything run in a temperature controlled oil bath? I saw a video from Mitutoyo and that's how they keep their master leadscrew at a fixed temperature when screw cutting.
@@evildrome no our motion stages are in free air. We keep the technical hall under 1K temperature deviation and encoder feedback loop controls the rest
I know it's been a while but at my job we have what is essentially a large pair of calipers to calibrate cinema cameras. In order to discover and correct for long distance accuracy we use the distance traveled and revolutions of the motor. It uses a belt and pulley along with a very nice absolute encoder. We note the error (difference) of where it ended up vs the target and use the encoder resolution as well as the revolutions of the pulley. So if the machine was 0.015" off we would use that distance multiplied by the ticks/mm of the encoder (a constant), divided by the number of revolutions made during the move. This would give us a long range error correction value that the machine can compensate with. Essentially the number of encoder ticks it should increase or decrease by with every revolution of the pulley. I believe a similar calibration technique could be used with a ball screw mechanism.
I understand NOTHING but I can't stop watching.
Precision engineering with German precision dry humour. God I love this guy!
6:04
When a ballscrew shaft is ground, the metal can already be very hard prior to grinding and the resulting screw can be far superior than a ballscrew that gets some hardening in its roll forming process.
Marco we see so much stuff in your videos we cant find nowhere else..TY.
And cant afford haha!
Made with carbon metal not a trace of cabon wood LMAO
Oh finally a new video. 😀
Just found this channel... Been binge watching since : )
I just love how you worked that ad right in there. Smooth as butter i didn’t see it coming and then BAMM like a freight train.
Your videos are usually pretty funny, but that joke at the end about rails getting replaced preemptively in industrial settings was hilarious.
Bigger companies do this all the time. Regular maintenance is important when your Nestle and bottling 10's of thousands of water bottles a day.
@@adisharr
I am not sure if you have ever replaced a ball screw, but it doesn't sound like it.
@@SystemsPlanet Most industrial machines (outside Germany at least) get run to death, rarely get the love or greasing they should.
Depends a lot on the application, but most companies will replace ball screws when it starts causing problems. If it's in a machine that NEEDS to run without a hitch, consumables will generally get replaced or at least checked for wear on a predetermined schedule. I used to work for a company that would always have a maintenance crew scheduled for holidays so they could do that sort of thing without creating excessive downtime.
The standard operating procedure in North America is: A more and more frequent motor overload error, operators get frustrated enough to complain, so maintenance come and grease it, same thing happens a few more times, maintenance get frustrated with greasing it every damn shift, and then they tear it open to find out it’s completely fucked, ball bearings all over the inside of the machine, parts are ordered in a hurry, often resorting to physically sending a guy to the distributor to get the parts faster, because the line is completely down and hemorrhaging money. You guys have a better system in Germany?
German precision oozing out of this video. I had a German accent for an hour after watching this. Love this channel! Subscribed!
Precision wood block table
Here in Vietnam we can get those linear rail and ball screw second hand for dirt cheap. They are often disassembled from old machines. Just got a pair of unused IKO LWA15 rails and NSK 1602 ball screw for like $40. $200 can get you a nice 400w servo with driver from Japanese brand like Yakaswa.
Any "Stuff Made Here" fam?
Looking up what screw balls are? 😂 Same
@@creativeoutlet3148 Ayyyy
@@creativeoutlet3148 lol same
No
That's why I'm here lol
I'm working with high precision CNC mills and we use 30mm diameter ballscrews with 16mm pitch. But the bearing blocks are something different. They cost around 1500€/piece and weight around 6-8kg I think. But we use much more beefier motors. 2.2kW per ballscrew.
That crackling noise in that nut hurted very badly.
Just gonna change the ballscrews at a customers machine tomorrow
Had no idea FPGAs could be so adorable. I need to dust off some micro-controller unworthy projects and exchange some financial details with Elektor.
Elektor: "only 0 left"
Me: "oh great... fuck my life."
My wallet: *quiet sigh of relief*
I can confirm that in 2025, FPGAs will go beying Kittens in the minds of serial-video-watchers.
I think it's important to note that the final hardening comes just before grinding (which happens after rolling in the case of rolled ball screws) and so the effect of surface hardening is minimal compared to the higher precision and therefore tolerances of purely ground ball screws.
Always interesting ! In my experience, too much precision is useless, because, at the end, the total deflexion of the structure, leadscrews, the motor head, the tool, etc. is very significant, but, of course, "too much precision" is better than "meh!". I'm saving money for the parts of my next CNC router. Thanks for sharing !
Oh, it seems I got lost in the CNC UA-cam rabbit hole. That said, now THIS is some serious DIY CNC shit.
FYI: You should look into Klipper if you are interested in interfacing a regular threaded OS with a realtime OS. Klipper is a 3d printer software that does all the heavy lifting on a computer (usually a Pi) and then uses one or more microcontrollers to schedule and execute commands.
Yeah, cool project. I think Cetus is also based on that principle
@@reps I honestly think it's the way forward for 3d printing as opposed to using STM32 based boards with webUI addons like the Duet. Plus it can be infinitely scalable. Want to have two Y-axis gauntries with two X-axis carriages with two independent extruders each? Slap a few cheap reprap boards together and hook them up to a Pi and install Klipper on everything.
YESSS! I freaking LOVE your videos!!!
FYI: micrometre = μm, micrometer = an instrument for measuring small distances
Thanks
nerd :)
@@reps fair, fair
I know this is off topic, but what is your planned controller setup? I know you have some LinuxCNC experience, but have you looked at the MachineKit? It’s a pretty cool fork, far more modern in architecture and much more modular ecosystem. You can find out more at machinekit.io.
I have no connection to the project, just believe that is superior and worth a look.
Came for the precision, subscribed for the humour! Nice and dry, just how I like it.
best video ever. inspired me to study engineering and will build a machine.
Finally, a new video!! I was getting really tired of watching reruns and can't seem to get my fix anywhere else! I just got my MK3 Extended last week and already started my collection of cheap Chinese knock-offs….I'm in too deep already and obsession/fascination with Micro Reps isn't going away..one video every couple months just won't suffice!
I could listen to you say "steinmeyer ballscrews" over and over on repeat endlessly. I wish I had your voice, fantastic vid
That's how we Germans say it ... 😀
The qualifying test for becoming a marine artificer in the royal navy in the 1970s was to build a miniature metal lathe.
By hand from scratch, to a maximum accuracy of so many thou.
Apparently creating those jack screws and whatever they made to run along it is tricky.
Thank you so much. You saved me a lot of time. Going to replace my end bearings and get that Tiny FPGA kit now! Excellent.
You are such a knowledgeable and funny guy.
Just because linear rails don't move freely, does not mean they are bad. They could just be preloaded, wich can be beneficial in some applications.
3:10 when your hardware is so precise that your nut has bolts inside it
Liquid nitrogen on an ATMega was the funniest niche shit ever. Thank you sir.
That tiny FPGA thing... I didn't knew such a thing existed! That's the size of an Arduino nano!
I did not know that Germans knew about humour LOL
ONE OF THE BEST TECHNICAL CHANNELS ON YT (and funny too)
Yep, turning the nut is tricky. It takes a while turning it back and forth to be ‘happy’ again. For a while it was trying to force out the plastic seal. At one end the plastic seal is held in by two tiny grub screws.
Your videos are awesome, I can't believe I hadn't discovered these sooner, bravo.
1.07 luckily you didn't fall on the staircase behind ... hahaha
I'm really glad I'm subscribed to this channel. I feel like the humor here is within the same vein as This Old Tony.
thank you for the lesson in angular contact bearings
Very good. I like your sense of humor too.
I love the shot at 3:37 where you can see a die with all the traces allong it.
Good humour and technical knowledge. Subbed.
A new video from Mr Reps makes my day.
Classic case of a "spec creep"
Jep
Know that feeling
@@johnsnow8186 en.wikipedia.org/wiki/Scope_creep
I got my first two 12mm ballscrews today from china, 600mm long with a straight nut, I hope they are not bent
Edit: Gets addressed in the 'Shaft' video.
Don't CNC machines usually control their travel using DRO? If built that way, the lead precision of a ball screw doesn't matter as much as the backlash. (I think "Umkehrspiel" called backlash in English.) Probably because the ball screw, because it is warmed by friction and cannot be protected as good, is much more susceptible to thermal expansion than a glass scale. Possible that a good controller even uses both to achieve sub micron positioning.
More, please sir! One of my favorite channels.
Your drift is likely caused by thermal expansion. You'll get about 10um/m change if your ball screw changes temperature by 1 degree. You can confirm this by heating the ball screw with your hand.
I actually shuddered when you rotated the ballscrew with abrasive in it
The lubrication sounds are very inspiring. Fruits & vegetables are good for you, Marco!
Nice to see some SMC stuff in the video. I have never used anything from them other than pneumatics but i got a tour around one factorie and they do make very high quality stuff....
A simple laser interferometer can be used to measure accuracy over long distances. All you have to do is to program maybe an arduino to count how many times the interference pattern cycles. The accuracy may not be great because you can't really properly calibrate it but it should be super precise, as long as you don't loose count.
Nice, I just replaced a Z-axis ball screw on a VM-3. Fun times.
Well I'm screwed with my M6 threaded rod and 5V stepper motors lmao
Linear rails have different amount of preload and various combinations of seals that will affect how easy they slide.
Anxiety when using expensive ball screws? We use them in a foundry enviroment where there's sand everywhere, they trash out about once a year.
Also, you know when linear guides are replaced? When the carriages explode from all the dirt and grease inside them and the rails look like an apprentice filed them out of one solid bar and got bored halfway through.
"These are the polar opposite to the Chinese ones"
Aaaaand of course they are german. Germany, the place where a a simple thread can be overengineered so it's super expensive but still being worth it lol.
Clearly you have never visited Japan...
Funny , ohh the humor , most excellent content. This is exactly the info I was looking for as I'm currently trying to repair a TL-1 Lathe : )
That's some quality hardware! I'm only worried a bit about this Z axis, it looks going to be 2-3 times longer than spacing between rails, this will amplify load on the rails, and then amplify deflection at the tip of an end mill even more. I might be overthinking it but i'd be tempted to make something like Okuma double column machining center.
Valid point!
A German tech nerd channel with a sense of humor?
Subbed!
It's not that unusual, check out bitluni.
Thank you for the unfiltered sharing of information. It is quite refreshing.
For testing longer range you could Mount an standing plate and Drive the carige against it..
Hey! Check out
Piotr Fox Wysocki's video on his Jianken ATC spindle.
I have! I even wanted to go down the granite machine path, but then a lot of steel happened ...
Wow ! I didn't know that guy ! Thanks for the info !
I was just pooping and was searching for some video to watch on the meantime.. And then I saw that you uploaded a new video! That was the best poop I had this year, thank you!
Good to know!
Er . . . too much to know.
You need to give your narrator a raise in wages. What a great voice.
May I once again express my appreciation for your hydrophobic humour! :grin:
Finally a new video! I'm so happy to see your CNC machine coming together😍 can't wait to see those beauty in action
There is a recent video how to clean and "upgrade" cheap linear bearing, like you are using at 7:45 the difference is outstanding
I used to work with these in laser trimmers and C02 lasers. The C02 had a 200 pound polished slab of granite that everything was mounted on
Hello, it's my first comment here.. First of all love your channel...So I am writing aboute the "el chepo chinese linear rails" i've bought some more then a year ago.. Frustrated over the laggy performance, etc... Solution disassemble the carriage submerge in alcohol (to clean some wierd oils inside) reassemble, greas up... It worked for me... Still going strong after a year or so of modernet to heavy use..
What's the amount of the slow drift? Steel has a coefficient of linear expansion of ~10-12 microns/meter/degrees c, so temperature expansion vs the desk should certainly shown up on your micron scale.
I am also German but have been living in the US for over 40yrs. I am looking to build a reasonably priced desktop machine to route/mill parts for my hobby. Why is it that I am also obsessed with precision and worry about thermal expansion of materials? I guess it’s in my genes? 🤪
To measure long distances you could attach levers to the encoder. It's the same technique that people used back in the day to convert large movements into small ones for precise machining. You'd be trading micrometer precision for mm or cm precision though.
You might want to consider adding a DRO to your CNC machine. You can get them cheaply on ebay up to ~2m+ lengths and its probably easier to make the glass ruler in the DRO nearly perfect than it is to make a perfect ball screw. You could use the DRO for absolute position in a feedback loop with the servo motor.
You are an asset to humanity.. and futue A.I overloards alike!
For measuring longer travel accuracy, a fairly cheap method would be to get one of the cheap 12" (~240mm) digital calipers. Note that it has to be one of the cheap ones, but for some reason nearly all of the cheaper digital calipers have serial output, and there are tons of tutorials for interfacing with them. Resolution isn't spectacular (+-.05"), but they are much cheaper than something like a lathe bed axis DRO and would likely provide some good data (at least for repeatability testing). At least in the US, they are normally avaliable for ~15USD, I would imagine they aren't much different in the EU. Plus, then you don't have to feel bad about hacking a nice starrett or mitutoyo instrument!
Nice to hear from you again
Thanks for sharing👍😀
dunno about the tiny fpga, but you can use the blue pill stm32 fr a cheaper/faster upgrade to the arduino
Yes, the $1 STM32F103C8T6 with true USB 2.0 at 72mhz ought to be enough. Maybe?
Whoa that SMC card motor is just so cool!
Hallo Marco, Ich habe mir auch die BK20 gekauft auf aliexpress, und sehe da sind ganz normale lager verbaut. Denkst du das die irgendwie ok isnd für den konstanten axialen druck auf zwei seiten? Ich brauche es fuur meine Fräsmaschine (machinable area = 2440 x 1220). Mein setup hat zwei 2525 ball screw spindles für die lange Y achsee, und eine 1616 für die X Achse. Denkst du es würde sich lohnen gleich jetzt vor der montage um zu rüsten, oder erst mal schauen was die billigteile hergeben? Danke für einen Tip!
Hello Marco. At 3:38 you show us a voice coil similar in construction with voice coil from hard disk. Please explain me how it remain fixed on the position. On hard disk if you apply +and- the voice coil goes to the end. If you reverse polarity - and+ it goes to the oposite end. The question is what kind of electricity makes this voice coil to remain fixed on a track on any other position betwen right end and left end ? This is interesting to put an osciloscope on the voice coil on this device and show us how can be stand still with incredible acuracy. Nobody know to answer me this question for several years. Thank you.
I love ball screws, but everytime I see one my mind flashes back to the $500 Bosch-Rexroth paperweight on my desk resulting from the spindle spinning off the shaft and onto a dirty floor.
you can get away with using thinner screws by tensioning them slightly, either between 2 angular contact bearings (use roller ones, preloading is hard on bearings that are mostly stationary), or rigid and rotating the nut. I like the chasing micrometers, but harmonised stiffness, adequate stiffness and vibration dampening is where it's at with diy cnc methinks. still, i wouldn't say no to those Steinmeyers either:)
Marco.. You should check out rotating nut instead of rotating screw
Why?
Less vibration since a long screw would flex while rotating. a nut that rotate around a static screw would not make the screw wobble. You could use thinner screw and improve over longer distance
ua-cam.com/video/4unEngqU09A/v-deo.html
ua-cam.com/video/WXv5breXGLw/v-deo.html
@@IBICO74 mkay, interesting! but I am already too far on the 'normal' route ... maybe later
3:37 Awww look at that little 6th generation iPod being assimilated.....
7:48 "they get replaced based on milage or time" soooo, i work as cnc lathe operator, and no they do not :D
That depends on the shop, where I work they get replaced BEFORE they fail, since they´re cheaper to replace than most of the products being machined!
At my old job they did replace them after operating hours. And yes this is done by a lot of companies as they said. It's cheaper to replace a rails + carriages before it fails rather than failing during a cnc job which will cost a lot more like failed material and downtime hours which can cost thousands of dollars.
@@Underp4ntz_Gaming_Channel It's also usually done when "you're already in there." If you've got a machine torn apart, and it's halfway to the replacement time, it's easier and cheaper to do it all at once.
well the good thing about carbon wood is that its actuall pretty good at absorbing vibration
glass linear scale for overall measurement and mapping.
Excellent video about a thing that gets ignored quite often.
One way I could think of measuring long distance movement, would be measuring rotation shaft movement vs fixed point via laser distance sensor.
You worry about the possible error induced by the table? Are you building a gravity wave detector? o.0
If I pick a handful of UA-camrs about 3D printing (you being one) and I can get us all all in a conference call with video if possible so “talking with hands to help with visuals” will help. ....
And in this live group call we form a “company/Organization” for my truly revolutionary design of a printer to be sold as a product. I’m not asking for money, I am a over the road semi truck driver, I make plenty of money for everything needed, I just don’t have the time to do anything other than talk really. And I live out of my Simi Truck. So I don’t have build space.
Most of my design is set in stone, but there are multiple ways to do different factors of my design, can we all discuss it and maybe add tweaks to make it better. But what we all discuss as a collective does not leave the project and stays private until it is ready for sale, can we all agree on this and talk about
No matter how many times I watch one of your uber crack me up videos, I still get a great chuckle! Super dooper. Mike's Radio Repair and Davey Jones? at EEV BLOG have recently experienced the displeasure of thumbs down bots and comment bots. Would you consider making a video called "Das Bots"? I apologize in advance for the edginess of the idea, but if anyone can pull it off, you das man. If I have offended, please forgive me. The quality and expertise of your sharp wit is no laughing matter. I have nothing but respect for you. And much admiration. Thanks!
Tiny fpga? It's time that you discovered the Parallax Propeller. The new P2 is mind blowing. Any/all of its "smart pins" can decode quadrature signals at sys clock rate (180 to 300+ MHz) . Eight independent processors can be programmed in C/BASIC/FORTH/ASM and Python is on the way.
German engineer with humour. Subbed
That tiny fpga looks f*n cool !
I'd recommend using a double ball set up not, a single.. take those plastic seals out & degrease the bearing balls and you'll find a good amount of play. The grease & plastic seals mask the ball screws axial play.
Genuine Hiwin rails take force to move because the fit is tight - I have some and they move just like those.