Very nice that you dedicated a full section to the Critical speed. I'm one of those people who talked about it in the previous posts, and I like to think that I could help you at least in a tiny bit. It's a small return for all the advice and information that I've learned from you. Great content
@@DrDFlo About the critical speed... Why did you not get leadscrews with a higher pitch? I think igus has some leadscrews with a really high pitch, you could move much faster with the same rpm. The torque of the NEMA 23 motors should be plenty.
@@qutlicopatlixhotutti6552 I was also thinking of the Igus lead screws as well as their high temperature options. I have also seen on some thermwood and I think multicam? cncs that use an hdpe (or at lest it looked like it) stabalizer block that supported the lead screw and rotated out of the way when the gantry passed , that could be a low cost solution
I would use brass for the drive nut, I service and build the parts for bucket wheel excavators from RWE in Germany and we use brass for these applications. Love the build, keep up the good work.
@@TheLordinio I've seen it described as milling bars of soap. It has outstanding chemical and thermal properties, but it's mechanical properties are horrible. Honestly? If I was to go to the trouble to make new nuts, I'd make them out of oilite.
I hope you have calculated the thermal expansion and a whopping in the aluminium the difference of 20 degrees Celsius to 100 degrees Celsius What an expansion approximately of 2.2mm at a distance of 1200 mm 8 mm spindle screw has only expansion approximately at the distance of 1.25MM but by inserting spring washers at the end you may be able to compensate for that I wish you good luck with the project
@@alejandroperez5368 the prusa did this for heat zones and expansion on the heat zones the build plate will not expand or contract that much due to the heat bed not directly mechanically attached to the heat bed
I feel like you could build one beastly battlebot with your shop as well :) Your production and passion you put into your videos is awesome, always look forward to new content !
@@DJ-wl5yi not currently. I'll be posting about it as I get it working. Right now I'm still assembling the frame of the kit which has plenty of coverage
Nice job but just be wary that PTFE can cold creep under load. Try to minimize the PTFE thickness and constrain the PTFE by metal where possible i.e. a thin PTFE part in a metal block. Keep up the great work!
Also, free handing the tap is not good when you want it to be square to the part. This alone could induce some of the lead screw whip see in the video, and cause binding and excess friction.
no worries about differences in thermal expansion? looks like the aluminium will expand 1-2mm more than the steel leadscrew when getting to chamber temp. bed could be tricky too at those temps/sizes
Add an accordian connecting the edge of each rail to the carriage on that rail, and have a smooth bearing attached at segments of the leadscrew along it to act as a moving track to prevent sag
I have been working as a tech in plastics extrusion and injection molding for 20 years. This extruser is cool but they missed something. It should have a suck back function. Wich pulls the screw back just a bit causing whats called suck back. It removes and reverses the pressure so you dont get that ooze when the extruder needs to move. Would be awesome with that function. Then it could move without oozing
Consider taking those lead screws back out and milling a flat at each end for the set screws. I'm picturing the set screw walking right up the thread over time.
Very nice build. I'm so envious about the CNC and laser cutter. Also the voron, which I will build myself in the near future. Keep up the great content
Interesting project. Subscribed. One note tho, rater then rotating the lead screw that gets wobbly at longer length. Rotate the nut instead. The draw back is that you have to have the motor mounted on the carrier thus it gets additional weights.
Moment of inertia is i^4 and is the measurement of mass from the center of mass. The higher the number the worse the whipping of the lead screw. You really DO an amazing job. I Enjoy your research.
I ran into the problem of lead screw sagging many times in the past, and while I always managed to solve it with more or less succes, I had this one idea I never had a chance to test. The idea is pretty simple, just one or more blocks (Teflon in your case) on either side of your carriage which can slide on the same rail, have a hole just a bit bigger than the screw diameter and are tethered to the carriage (and to the next block if there are more) by a string or a thin strip plastic or metal with length equal to a portion of the screw which should be stabilized (approximately 1/4 of total length is two blocks are used, 1/8 if four etc...). This way the carriage always drags the blocks behind and pushes the others. Maybe using elastic string would work even better is fixed at both ends to the frame. Some length is lost, but the blocks can be pretty thin if guided well. Just an idea in case you find out you need greater speeds. If you wanted to use linear rails, I suppose the wipers could be laser cut from silicone rubber sheet easily enough. Some silicones are rated for 230 oC or even more.
Beautiful machine! I would like to ask you to make some runs without a heated chamber or plate to explore the challenges of cold printing and if it is possible at all at such scale. I have this wedge in my brain that tells me 99 ways of printing in a cold environment will not work but there is 1 correct way that can make everything fit together and you can print without the need of heating or cooling.
I'm not sure of you did it after and just didn't film it, but from the way you applied the idle nut and motor to the lead screws doesn't tension them at all. I would think you would apply the motor side first, then run your idle nut in to pull the desired tension before locking the set screw down.
Amazing build. Really ambitious that You're planning to use high temperature materials too. Fyi, you can also increase the critical speed of a drive screw by pre-tensioning it.
Another way to go is spin the nut and leave the screw stationary which eliminates the problem. But then the motor is in the heated space and attached to the drive where it's inertia is an issue. We really need a product that no-one makes. A tube ball screw. Then the stiffness is high, but the mass is low.
@@court2379 spinning the nut is a tricky trade off. While it is a small and light part, it's usually 3-4 times larger diameter so often ends up with a higher rotational inertia than the spinning screw. For the same reason a tubular screw doesn't help with rotational inertia. That said, you can buy tubular screws. They allow you to water cool the screw for high precision applications.
@@martylawson1638 I doubt the nut inertia is going to be higher than the shaft when you are getting into these sizes due to needing to use larger shafts to deal with loads and whipping, and due to the long lengths, but ultimately it would have to be calculated. I have never seen the hollow ball screws, but if they are for cooling purposes the design is not likely what you would need here. Cooling likely uses a small bore. For lowered inertia, the wall would need to be as thin as possible to keep the inertia close to that of the solid shaft. Mostly likely a hardened alloy, maybe 17-7. Then it would be stiffened by it's cross section and material. Since the loads are small, I am not sure screw drive is really the best option here. Great for accuracy and staying in place when not being driven, but this printer is huge. It needs to run as fast as possible to get a part done in days instead of weeks. There is no perfect solution though and just depends on what things the design focus is on as to what is best (apart for just bad engineering, and not saying that is the case here).
Interesting experiment if you're wanting to increase the diameter of threaded rod or screw size but you don't want the mass to where you can print faster but you don't get the SAG in the rod and the whipping that it causes then have threads turned on a lave in thick wall pipe it should keep its read rigidly but yet you don't have the mass
You can easily CNC rout Aluminum Composite Panels using a V-bit and the rout-and-return method to make custom electrical enclosures. I model them using the Fusion 360 sheet metal workspace to get the flat pattern.
I was looking into this the other day after realizing how expensive enclosures and backplates are currently ($70 for a 21x21" painted backplate?? lol). However, I think for larger boxes, you would be very hard-pressed to save money (and time) building an enclosure or backplate yourself unless you just happened to already have the materials -- most of the cost of the enclosures is just raw material (most good quality electrical enclosures are 14ga powder-coated steel, aluminum and SS are more expensive). I would still be interested to see David (or somebody else) do it, though. lol
I have dreamt of lead screws for my Y axis since 2017. I went looking for M8 trapezoidal replacement and found a supplier at Aliexpress that sells them in much higher pitch than you are using. My idea was to use a closed loop stepper by MKS, and experiment with various pitch values in the range of 8 to 16mm. Your RPM per given feedrate and travel will be dramatically lower thus avoiding the whipping as you exhibited. There will be the matter of anti back lash feature to add in that pre-loads the lead nut..Being that the lead nut is brass as are currently offered, there would be the need for regular lube. I understand that the mass of the components and assemblies are orders of magnitude larger than a little bed slinger. I have no idea if you are dealing with any "stickshun" But maybe it is worth a look. The closed loop option is a small circuit board that plugs in where your drivers go and bolt on to the body of the NEMA23, at least you can rest assured that every pulse will be accounted for. All you have to beyond that is hack the firmware. to suit your choice of pitch. I would be happy to share sources.
My custom-built FDM printer is "only" abut 650mm cubed with a 310mm cubed build volume, and it was a pretty crazy project to build. I shudder at the thought of something 9 times larger...
Would be interested to see how that large bed heats up.. Prusa in their new large printer went with small modular heater stating one large heated bed can warp more..
cool machine you made)) in order to make the parts more detailed, I would add a small spindle and cut each layer in layers with a cutter, a cutter with a small diameter) the rigidity of the machine allows you to mill plastic)
@@khaderach19 right the pellets are much cheaper, but did he really build a huge ass machine just to make 1kg prints at a time? Heck that could be made on a foot cubed machine… no his parts will still be extremely expensive for the size they will need to be whatsoever it may be.
Incredible video production here. 👏 I'm in the middle of my mechE degree, so I just eat this kind of content up. Absolutely loved when you touched on the critical speed of the leadscrews and how mass moment of inertia comes into play. Consider me 'Subscribed'
Thanks for sharing, you taught me a few things! One problem I've noticed though, your Z leveling system with the multiple Z motors is only going to work without breaking things if there is some flex somewhere where there shouldn't be flex. Take a look at the Hevort printer, the short linear rails just under where the bed mounts (I can't find the words to explain it, but you'll see what I mean).
I think he's addressed that with the spherical bearings, they allow a degree of freedom to prevent stress. I think the hevort project uses that decoupled approach on their Z access to work around the runout in cheaper ballbearing lead screws
man. a larger leadscrew (or ballscrew) not sure which your using. would have taken so much of that wobble out. love the build thus far though. looks great
Amazing you unlike most understand much like heated chamber requirements for exotic thermoplastics 140c plus !!! CHEERS finally! the only thing i think you may have some back lash resonance super supporting you here going for high temp resins this chamber will need fire pillows to keep your hydro in the box and maybe a bellow set in my opinion great job selecting Teflon and PC v wheels as back up for now, but you may need the bellows to isolate the heats from thermal expansions on the x,y keep it up all eyes
This is an intense project, it will be interesting to see what you can print with it. I shudder to think of how much it will cost to feed it with pellets, even with lower cost materials like ABS. And printing with PEEK.. there's just no room for error, a failed print could cost hundreds along with the time and effort to dry the pellets out
how did you match up the threads of the dual teflon blocks for the smaller carriages? With two in series, I would have thought they would require some specific consideration.
I would consider belt driven axis and the use of closed loop servos and you'll get a much quitter machine and with much less vibrations from the lead screws. Not going to belts consider ball screws...
I watched your SLA build and it was very involved and detailed. You are producing great content. Do you have your own business? Where did you learn your skills?
Regarding for lead screws proportional to the fourth power, is that related to the second moment? Like because there''s that extra distance from the centre point? I may be misremembering it all, I do need to go over all that again
Why didn't you use multiple 'regular size' bed heaters and wired them in paralel or even enable only those you print on currently (with plastics wicht doesn't require a heated chamber)
Would it be possible to add bushings/bearings midway between the carriage and the ends of the leadscrew on springs to help reduce the whipping of the leadscrew? As the carriage nears the end of the leadscrew, the springs would compress to keep the bushing centered.
Took a while to figure out your vision here. These bearings will need to move at 1/2 the speed of the carriage then? May work. Well, something needs to be done. Perhaps a system where the screw was 51% enclosed, resting in a cup. I know automotive drive shafts are hollow. Do hollow lead screws even exist?
The solution would be a stationary and tensioned leadscrew an a rotating nut. But keep in mind simple leadscrews aren't nowhere to be meant for high speeds. I'd at least use 1204 cheap ballscrews for that matter. Our DIY large printer will feature 15mm belts for X and Y.
If you haven't found a use for all those removed bearings I take donations! Killer build, excited to see the final final and what your first print project is going to be!
wouldn't it be possible to make some kind of scizor frame supports for the lead screws like enclosing the frame in a scizor lift the supports would then slide along the lead screw and divide it's length in half or quoters, thirds or wkatever i know supports on both sides could reduce some travel but it would be like travel reduced by milimeters vs screw resonance frequency multiplyed by the number of supports in theory 2 times shorter screw should be able to move 2 times faster and accuracy should increase in the low end what do you think, worth the effort or too much complexiti?
I'm really curious to see how you'll tackle all the challenges of printing engineering polymers in such a massive printer. My first thought is that this is not the proper printer for that task, but I'd love to be proven wrong.
Bed adhesion will be a massive pain. This will not be a successful project. And who needs to print this large petg or pla parts? Abs and asa parts will warp like hell on this machine
How come you went with lead screws vs. those larger kind of ball screws? I figured ball screws would be better for the longer travels like this but are they worse for some reason? (other than cost)
Hi. This is an awesome build. I am creating a very similar build myself. I was curious if you had a system figure out yet for your pellet distribution? My build is 1500x3000 and I think I'm moving towards a fan blown process but am curious what your solution is. Good build. I love the tips.
It's looking great so far. I have a question about the Y axis cable chain support - It appears to be rigidly fixed to the two Z axis plates, doesn't that defeat the point of your spherical bearing mount for the Y axis? For the cooling of the motors within the chamber, you could consider a peltier on each motor in order to reuse that thermal energy. The amount of energy to move is not huge and the energy you'd need to put into the peltier would offset whatever you need to put into the chamber heater for any lost heat.
omg thats the biggest single heater ever... any idea how much total draw your expecting less the chamber of course... you also look to have decent pitch not to much or little nice job ! this makes my day i am not alone doing this less the size of course using same motors in my open stratasys conversions with duet2 on rrf
instead of using a lead screw with a nut block, it should be better if the ball screw is utilized also, to increase your translation speed, the ball screw can offer wide range lead value.
Great work, I am hoping to do this build with my younger brother who is going off to college for engineering this august. Any way we can get the BOM and the CAD for all the additional brackets you manufactured? Thanks Dr. D Flo!
I think belt drive with gear reduction from the motor would have been way better for X and Y ,, also did you consider using high heat paint for the panels as it will flake if not ,, keep up the good work !
Why not use metal for the nut block instead? I would expect those plastic ones to wear quickly. Ball screw setup with anti backlash nut would cost more but, taking the thing apart every time those wear out would suck.
What motherboard and drivers are you using? I am new to building machines and also want to use nema 23 motors, but it seems difficult to find good information.
Very nice that you dedicated a full section to the Critical speed. I'm one of those people who talked about it in the previous posts, and I like to think that I could help you at least in a tiny bit. It's a small return for all the advice and information that I've learned from you. Great content
Yes your comments have been very helpful!
@@DrDFlo About the critical speed... Why did you not get leadscrews with a higher pitch? I think igus has some leadscrews with a really high pitch, you could move much faster with the same rpm. The torque of the NEMA 23 motors should be plenty.
@@qutlicopatlixhotutti6552 I was also thinking of the Igus lead screws as well as their high temperature options. I have also seen on some thermwood and I think multicam? cncs that use an hdpe (or at lest it looked like it) stabalizer block that supported the lead screw and rotated out of the way when the gantry passed , that could be a low cost solution
The build is looking amazing. I can't wait to see the world's largest benchy
And to see him row around a pond in it😁 (it isn't a very good boat design...)
Those gantry brackets you milled are absolutely gorgeous.
*Ivan Miranda enters chat*
Just found your channel. Love it!
I would use brass for the drive nut, I service and build the parts for bucket wheel excavators from RWE in Germany and we use brass for these applications. Love the build, keep up the good work.
jup ptfe probably won't live long under load
Came here to say this
@@TheLordinio I've seen it described as milling bars of soap. It has outstanding chemical and thermal properties, but it's mechanical properties are horrible.
Honestly? If I was to go to the trouble to make new nuts, I'd make them out of oilite.
I hope you have calculated the thermal expansion and a whopping in the aluminium
the difference of 20 degrees Celsius to 100 degrees Celsius What an expansion approximately of 2.2mm at a distance of 1200 mm
8 mm spindle screw has only expansion approximately at the distance of 1.25MM
but by inserting spring washers at the end you may be able to compensate for that
I wish you good luck with the project
I don't think so. Otherwise the Prusa XL wouldn't have that modular bed plate design... And it's only 350mm in size...
@@alejandroperez5368 the prusa did this for heat zones and expansion on the heat zones the build plate will not expand or contract that much due to the heat bed not directly mechanically attached to the heat bed
I feel like you could build one beastly battlebot with your shop as well :) Your production and passion you put into your videos is awesome, always look forward to new content !
I'd be curious to see him try this. It's a completely different set of challenges, but I think he could handle it.
Part 1 made me really want to try a pellet extruder on a smaller scale. I'm now currently assembling a ratrig vcore 3 500 with a mahor pellet extruder
That sounds like a BEAST! Any online presence to follow that build?
@@DJ-wl5yi not currently. I'll be posting about it as I get it working. Right now I'm still assembling the frame of the kit which has plenty of coverage
hope this works. a 500mm ratrig is on my business road map and a pellet extruder is a great idea on it
Looks great - can't wait to see the next part. This'd be great for printing furniture too, for example. "You wouldn't download a car"... why not?
Also I'd look at using support blocks positioned by concertina mechanisms to reduce the unsupported length on your leadscrews.
open builds is great, ordered my aluminum extrusions through them... Great Prices, My kinda website! -Props that thing is a beast!
ohhh i remember the noise my ender 5 made right out of the factory, my wife would love this thing inside the garage, 2 floors below our bedroom^^
It amazes me that your channel still has sub 100K viewers. Lots of good analysis and information.
I'm so hyped for this beast to print a gigantic Benchy!
Nice job but just be wary that PTFE can cold creep under load. Try to minimize the PTFE thickness and constrain the PTFE by metal where possible i.e. a thin PTFE part in a metal block. Keep up the great work!
Also, free handing the tap is not good when you want it to be square to the part. This alone could induce some of the lead screw whip see in the video, and cause binding and excess friction.
no worries about differences in thermal expansion? looks like the aluminium will expand 1-2mm more than the steel leadscrew when getting to chamber temp. bed could be tricky too at those temps/sizes
Add an accordian connecting the edge of each rail to the carriage on that rail, and have a smooth bearing attached at segments of the leadscrew along it to act as a moving track to prevent sag
I have been working as a tech in plastics extrusion and injection molding for 20 years. This extruser is cool but they missed something. It should have a suck back function. Wich pulls the screw back just a bit causing whats called suck back. It removes and reverses the pressure so you dont get that ooze when the extruder needs to move. Would be awesome with that function. Then it could move without oozing
Can't wait for the last video and see how it all comes out.
Consider taking those lead screws back out and milling a flat at each end for the set screws. I'm picturing the set screw walking right up the thread over time.
Very nice build. I'm so envious about the CNC and laser cutter. Also the voron, which I will build myself in the near future.
Keep up the great content
Interesting project. Subscribed. One note tho, rater then rotating the lead screw that gets wobbly at longer length. Rotate the nut instead. The draw back is that you have to have the motor mounted on the carrier thus it gets additional weights.
That sound of electric motors being fed square waves!!!
Moment of inertia is i^4 and is the measurement of mass from the center of mass. The higher the number the worse the whipping of the lead screw. You really DO an amazing job. I Enjoy your research.
I ran into the problem of lead screw sagging many times in the past, and while I always managed to solve it with more or less succes, I had this one idea I never had a chance to test. The idea is pretty simple, just one or more blocks (Teflon in your case) on either side of your carriage which can slide on the same rail, have a hole just a bit bigger than the screw diameter and are tethered to the carriage (and to the next block if there are more) by a string or a thin strip plastic or metal with length equal to a portion of the screw which should be stabilized (approximately 1/4 of total length is two blocks are used, 1/8 if four etc...). This way the carriage always drags the blocks behind and pushes the others. Maybe using elastic string would work even better is fixed at both ends to the frame. Some length is lost, but the blocks can be pretty thin if guided well. Just an idea in case you find out you need greater speeds.
If you wanted to use linear rails, I suppose the wipers could be laser cut from silicone rubber sheet easily enough. Some silicones are rated for 230 oC or even more.
Why not some tight fitting telescoping Teflon
Beautiful machine! I would like to ask you to make some runs without a heated chamber or plate to explore the challenges of cold printing and if it is possible at all at such scale. I have this wedge in my brain that tells me 99 ways of printing in a cold environment will not work but there is 1 correct way that can make everything fit together and you can print without the need of heating or cooling.
The Dr. is back at the office!
Wow, very excited to see the next episode!
This thing is crazy. However thermal Expansion is crazy and the wobbly X Leadscrew should be adressed.
Wow, awesome build project! Looking forward to the next episode!
I'm not sure of you did it after and just didn't film it, but from the way you applied the idle nut and motor to the lead screws doesn't tension them at all. I would think you would apply the motor side first, then run your idle nut in to pull the desired tension before locking the set screw down.
The leadscrew wobble of the X-Axis is crazy... you realy should swhicht that to metal core timing belts. There are heat resistant versions available.
Amazing build. Really ambitious that You're planning to use high temperature materials too. Fyi, you can also increase the critical speed of a drive screw by pre-tensioning it.
Another way to go is spin the nut and leave the screw stationary which eliminates the problem. But then the motor is in the heated space and attached to the drive where it's inertia is an issue.
We really need a product that no-one makes. A tube ball screw. Then the stiffness is high, but the mass is low.
@@court2379 spinning the nut is a tricky trade off. While it is a small and light part, it's usually 3-4 times larger diameter so often ends up with a higher rotational inertia than the spinning screw. For the same reason a tubular screw doesn't help with rotational inertia. That said, you can buy tubular screws. They allow you to water cool the screw for high precision applications.
@@martylawson1638 I doubt the nut inertia is going to be higher than the shaft when you are getting into these sizes due to needing to use larger shafts to deal with loads and whipping, and due to the long lengths, but ultimately it would have to be calculated.
I have never seen the hollow ball screws, but if they are for cooling purposes the design is not likely what you would need here. Cooling likely uses a small bore. For lowered inertia, the wall would need to be as thin as possible to keep the inertia close to that of the solid shaft. Mostly likely a hardened alloy, maybe 17-7. Then it would be stiffened by it's cross section and material.
Since the loads are small, I am not sure screw drive is really the best option here. Great for accuracy and staying in place when not being driven, but this printer is huge. It needs to run as fast as possible to get a part done in days instead of weeks.
There is no perfect solution though and just depends on what things the design focus is on as to what is best (apart for just bad engineering, and not saying that is the case here).
cant wait to see the first print run
I cannot wait for the first print!
Interesting experiment if you're wanting to increase the diameter of threaded rod or screw size but you don't want the mass to where you can print faster but you don't get the SAG in the rod and the whipping that it causes then have threads turned on a lave in thick wall pipe it should keep its read rigidly but yet you don't have the mass
You can easily CNC rout Aluminum Composite Panels using a V-bit and the rout-and-return method to make custom electrical enclosures. I model them using the Fusion 360 sheet metal workspace to get the flat pattern.
I was looking into this the other day after realizing how expensive enclosures and backplates are currently ($70 for a 21x21" painted backplate?? lol). However, I think for larger boxes, you would be very hard-pressed to save money (and time) building an enclosure or backplate yourself unless you just happened to already have the materials -- most of the cost of the enclosures is just raw material (most good quality electrical enclosures are 14ga powder-coated steel, aluminum and SS are more expensive). I would still be interested to see David (or somebody else) do it, though. lol
I have dreamt of lead screws for my Y axis since 2017. I went looking for M8 trapezoidal replacement and found a supplier at Aliexpress that sells them in much higher pitch than you are using. My idea was to use a closed loop stepper by MKS, and experiment with various pitch values in the range of 8 to 16mm. Your RPM per given feedrate and travel will be dramatically lower thus avoiding the whipping as you exhibited. There will be the matter of anti back lash feature to add in that pre-loads the lead nut..Being that the lead nut is brass as are currently offered, there would be the need for regular lube. I understand that the mass of the components and assemblies are orders of magnitude larger than a little bed slinger. I have no idea if you are dealing with any "stickshun" But maybe it is worth a look. The closed loop option is a small circuit board that plugs in where your drivers go and bolt on to the body of the NEMA23, at least you can rest assured that every pulse will be accounted for. All you have to beyond that is hack the firmware. to suit your choice of pitch. I would be happy to share sources.
My custom-built FDM printer is "only" abut 650mm cubed with a 310mm cubed build volume, and it was a pretty crazy project to build. I shudder at the thought of something 9 times larger...
GE12C for the win! Glad to see those being part of the build! Stop stepping on the bed hahaha
Thanks for your suggestion!!
If leadscrew flex becomes an issue, maybe a mini carriage/bearing combo could work? Very very cool build
Would be interested to see how that large bed heats up.. Prusa in their new large printer went with small modular heater stating one large heated bed can warp more..
Sounds like you have a product you can sell now with those teflon nut blocks. I'm sure you're not the only one that needed those before
cool machine you made))
in order to make the parts more detailed, I would add a small spindle and cut each layer in layers with a cutter, a cutter with a small diameter) the rigidity of the machine allows you to mill plastic)
that thumbnail brings up repressed memories
wish i didnt get this reference
not gonna lie, that spherical bearing would make a killer wedding band for a dork like me
This thing is pretty incredible. Excited to see the first layers. What kind of electrical service is run to this beast?
PEEK parts of this size will be sooooo expensive! Great job and thanks for this amazing build series.
Hence the pellet extruder. $40/kg vs $600/kg filament
@@khaderach19 right the pellets are much cheaper, but did he really build a huge ass machine just to make 1kg prints at a time? Heck that could be made on a foot cubed machine… no his parts will still be extremely expensive for the size they will need to be whatsoever it may be.
I would definately use slider couplers with this kinda of inertia even though it has thrust washers
6:10 hold on. I think its important to check the bearing carrier. It might be in plastic. I would tear one down to see.
The data sheet the came with the metal shielded bearing said good for up 250C operation
Incredible video production here. 👏 I'm in the middle of my mechE degree, so I just eat this kind of content up.
Absolutely loved when you touched on the critical speed of the leadscrews and how mass moment of inertia comes into play.
Consider me 'Subscribed'
Thanks for sharing, you taught me a few things! One problem I've noticed though, your Z leveling system with the multiple Z motors is only going to work without breaking things if there is some flex somewhere where there shouldn't be flex. Take a look at the Hevort printer, the short linear rails just under where the bed mounts (I can't find the words to explain it, but you'll see what I mean).
I think he's addressed that with the spherical bearings, they allow a degree of freedom to prevent stress. I think the hevort project uses that decoupled approach on their Z access to work around the runout in cheaper ballbearing lead screws
Finally is right! Very excited to see this.
man. a larger leadscrew (or ballscrew) not sure which your using. would have taken so much of that wobble out. love the build thus far though. looks great
Amazing you unlike most understand much like heated chamber requirements for exotic thermoplastics 140c plus !!! CHEERS finally! the only thing i think you may have some back lash resonance super supporting you here going for high temp resins this chamber will need fire pillows to keep your hydro in the box and maybe a bellow set in my opinion great job selecting Teflon and PC v wheels as back up for now, but you may need the bellows to isolate the heats from thermal expansions on the x,y keep it up all eyes
It's awsome!! Can you share CAD file or BOM List please?? I wanna make it too.
Amazing explanations and good way to show how to make things to ensure good results💪💪💪💪
This is an intense project, it will be interesting to see what you can print with it. I shudder to think of how much it will cost to feed it with pellets, even with lower cost materials like ABS. And printing with PEEK.. there's just no room for error, a failed print could cost hundreds along with the time and effort to dry the pellets out
how did you match up the threads of the dual teflon blocks for the smaller carriages? With two in series, I would have thought they would require some specific consideration.
Thanks for the video, i want to see you inside a benchy asap haha
I would consider belt driven axis and the use of closed loop servos and you'll get a much quitter machine and with much less vibrations from the lead screws. Not going to belts consider ball screws...
5:55 Teflon is great and unfortunately is in the body of almost every living civilised human being and will never go away.
I watched your SLA build and it was very involved and detailed. You are producing great content. Do you have your own business? Where did you learn your skills?
Incredible build
What a creator, bravo!
It would be convenient to have a link to part 1 somewhere in the description :)
Regarding for lead screws proportional to the fourth power, is that related to the second moment? Like because there''s that extra distance from the centre point?
I may be misremembering it all, I do need to go over all that again
Great video, you inspire me with every video!
Thanks, that has a lot of useful experimental information!
I've been so excited for this! Keep up the great work. 😁
Why didn't you use multiple 'regular size' bed heaters and wired them in paralel or even enable only those you print on currently (with plastics wicht doesn't require a heated chamber)
Would it be possible to add bushings/bearings midway between the carriage and the ends of the leadscrew on springs to help reduce the whipping of the leadscrew? As the carriage nears the end of the leadscrew, the springs would compress to keep the bushing centered.
Took a while to figure out your vision here. These bearings will need to move at 1/2 the speed of the carriage then? May work.
Well, something needs to be done.
Perhaps a system where the screw was 51% enclosed, resting in a cup.
I know automotive drive shafts are hollow. Do hollow lead screws even exist?
The solution would be a stationary and tensioned leadscrew an a rotating nut. But keep in mind simple leadscrews aren't nowhere to be meant for high speeds. I'd at least use 1204 cheap ballscrews for that matter. Our DIY large printer will feature 15mm belts for X and Y.
I can't wait to see the Part3 ! When will it come out?
If you haven't found a use for all those removed bearings I take donations! Killer build, excited to see the final final and what your first print project is going to be!
wouldn't it be possible to make some kind of scizor frame supports for the lead screws like enclosing the frame in a scizor lift the supports would then slide along the lead screw and divide it's length in half or quoters, thirds or wkatever
i know supports on both sides could reduce some travel but it would be like travel reduced by milimeters vs screw resonance frequency multiplyed by the number of supports
in theory 2 times shorter screw should be able to move 2 times faster and accuracy should increase in the low end
what do you think, worth the effort or too much complexiti?
I like everything about this vid.
Where did you get that Metric T8 tap, because I have been looking for one that will fit the openbuilds lead screws
Excelente trabajo 👍👍 se ve que sabes mucho de este tema ,felicitaciones
I'm really curious to see how you'll tackle all the challenges of printing engineering polymers in such a massive printer. My first thought is that this is not the proper printer for that task, but I'd love to be proven wrong.
Bed adhesion will be a massive pain. This will not be a successful project.
And who needs to print this large petg or pla parts?
Abs and asa parts will warp like hell on this machine
@@alejandroperez5368 Ah, a classic negative armchair expert youtube comment.
I think there is a reason you couldn't find ptfe drive nuts. It isn't very strong. It will be interesting to see if it holds up.
Waiting for the linear rail upgrade lmao, I’d also be a little more concerned when standing on the build plate
Add hoses and common hair dryers to speed up the chamber heating.. should help.. OR wait a very loooong time
How come you went with lead screws vs. those larger kind of ball screws? I figured ball screws would be better for the longer travels like this but are they worse for some reason? (other than cost)
Fantastic project. Are you going to be manufacturing with this printer? Looking forward to more videos!
The wiring montage. 👌🏼
Nice project looks similar to what I’m building (600mm x 1200mm) but i went with chinese linear rails and ball screws
There is a thing that gives you should get one of those kits that can do multi color extrusion threw 1 head
Hi. This is an awesome build. I am creating a very similar build myself. I was curious if you had a system figure out yet for your pellet distribution? My build is 1500x3000 and I think I'm moving towards a fan blown process but am curious what your solution is.
Good build. I love the tips.
This looks like it will be super interesting. How cool 😎 👍
It's looking great so far. I have a question about the Y axis cable chain support - It appears to be rigidly fixed to the two Z axis plates, doesn't that defeat the point of your spherical bearing mount for the Y axis?
For the cooling of the motors within the chamber, you could consider a peltier on each motor in order to reuse that thermal energy. The amount of energy to move is not huge and the energy you'd need to put into the peltier would offset whatever you need to put into the chamber heater for any lost heat.
Interesting idea.
omg thats the biggest single heater ever... any idea how much total draw your expecting less the chamber of course... you also look to have decent pitch not to much or little nice job ! this makes my day i am not alone doing this less the size of course using same motors in my open stratasys conversions with duet2 on rrf
instead of using a lead screw with a nut block, it should be better if the ball screw is utilized also, to increase your translation speed, the ball screw can offer wide range lead value.
Why did you choose flexible motor joints? Don't they introduce play in the axis?
Good luck compensating the thermal expansion!
Great work, I am hoping to do this build with my younger brother who is going off to college for engineering this august. Any way we can get the BOM and the CAD for all the additional brackets you manufactured? Thanks Dr. D Flo!
it would be complicated, but what if you had a smaller system of movement for smaller movements, while the large is for long travel.
I like it, nice and quiet 😂
I think belt drive with gear reduction from the motor would have been way better for X and Y ,, also did you consider using high heat paint for the panels as it will flake if not ,, keep up the good work !
Honestly I agree with you there. Beefy enough brand name belts and you get away from weight and many issues with drive screws wobbling.
Why not use metal for the nut block instead? I would expect those plastic ones to wear quickly. Ball screw setup with anti backlash nut would cost more but, taking the thing apart every time those wear out would suck.
What motherboard and drivers are you using? I am new to building machines and also want to use nema 23 motors, but it seems difficult to find good information.