Is the whole arm hanging via the leadscrew from the motor with a FLEXIBLE coupler or is the leadscrew supported by a lower bearing ? The print quality is rather poor print. Note that I don't criticize the kinematic of the machine (to lay bricks, pour concrete to 3D print a house, it would be the way to go), but the way it is built here. This kind of machine must be well made not "cheap".by MKSA - Polar Machines, SCARA, Robot Arms
Quotethe_digital_dentist You still need bearings, a mount, a motor, and means to couple to the shaft at the input and an output shaft. How many hours and what additional cost is there compared to just spending a few more $ and getting a Rino? That's why my development of the device using garage door gears stopped. OTOH, a low cost stepper driven worm gear would be useful for all sorts of thiby MKSA - CoreXY Machines
Quoteo_lampe QuoteMKSA Quoteo_lampe Of course, the screws will rotate. They have to ! Where have you two been at physics classes? So please explain the Z movement with both the screw and the nut rotating (the nut is part of the stepper rotor) ! Sorry, I have to apologize. I fooled myself, because I knew the leadscrew does rotate. But you have to keep it from spinning to get axial movement. Nby MKSA - CoreXY Machines
Quoteo_lampe QuoteMKSA Quotethe_digital_dentist ..... Your CAD model looks like you have put bearings on the ends of the screws, but if I understand what you're doing correctly, the screws aren't going to rotate, so bearings won't be needed. Congratulation doc, you are the only one who spotted the obvious fault ! In fact, the screw WILL rotate at an unpredictable speed depending on nut frictionby MKSA - CoreXY Machines
Quotethe_digital_dentist ..... Your CAD model looks like you have put bearings on the ends of the screws, but if I understand what you're doing correctly, the screws aren't going to rotate, so bearings won't be needed. Congratulation doc, you are the only one who spotted the obvious fault ! In fact, the screw WILL rotate at an unpredictable speed depending on nut friction and counter motor torquby MKSA - CoreXY Machines
Quoteandornot QuoteMKSA You were the first to claim we misunderstand, isn't ? OK, then I will wait for your proper drawing. I have read several of your recent posts and all you have done is criticised their designs, what machines have you designed? I have praised a couple of designs because they were sound AND/OR ingenious AND/OR well made. NOT my fault if the majority of "designs" fail to meeby MKSA - CoreXY Machines
You were the first to claim we misunderstand, isn't ? OK, then I will wait for your proper drawing.by MKSA - CoreXY Machines
Quoteandornot I think there is a misunderstanding on how i propose the z axis will work, let me draw it properly in 3d cad and then i will post it on this thread. By the look of just your Z system, it is clear it is over constrained. Concepts you seem to misunderstand. A proper CAD package will show you what is wrong when you assemble the parts. Now, quite frankly, you should try to copy a weby MKSA - CoreXY Machines
Should be fun for you to program the firmware but frankly from a mechanical point of view this machine is a piece of junk. Just looking at it makes my eyes sore. Anyway, an other attempt to cash on a different design.by MKSA - Polar Machines, SCARA, Robot Arms
Quite an achievement, I reckon. And no auto bed leveling ? Shake it in a trunk, put it up, power "et voila". Indeed, when good engineering practice and proper assembly methods are used. Definitely belts for the Z are a good choice for tall machine and worth the worm gearbox.by MKSA - CoreXY Machines
It is the solution. Do you see autobed leveling used by people building decent cartesian machines ? If you need it, then your machine is poorly designed/made. Of course, on a Delta, it is a different story.by MKSA - CoreXY Machines
Just use the proper "assembly command" on your CAD softwareby MKSA - CoreXY Machines
No need for open source. If it works it will be copied by others in Shenzhen and offered at a reduced price.by MKSA - Crowdfunding Projects Announcements
"Tuned mass damper to allow fast printing" great idea but why they print so slowly ? Salesman B....T. An other one again !by MKSA - Crowdfunding Projects Announcements
The simplest most efficient way to avoid auto bed level problems is no auto bed level. Not necessay on a properly built cartesian machine.by MKSA - CoreXY Machines
What about removing 6 and tension the belt by moving the motor like it is done in many machines for simple ink printer to heavy farm machinery ? The less pulleys the best.by MKSA - CoreXY Machines
Just came across. What advantage compared to even a simple Prusa ? How can century old mechanism be patented just because it is used in a 3D printer ?by MKSA - General New Machines Topics
Just saw the schematic. It is indeed a bridge. Looks like 2 branches are made with I suppose, 3 tracks each, the other 10k ref R. Op amp direct to the ADC. All signal treatment done by software. Much more sophisticated and versatile than the Piezo system where it is done via OP amp and comparator. Really neat.by MKSA - Delta Machines
Quotedougal1957 QuoteQdeathstar Quotedougal1957 QuoteQdeathstar ah. I'm curious about it, where is it on the pcb? Could you take a pic Picture of what exactly? if you mean the strain gauges then they are actually designed into the PCB Traces so not much to be seen on a photo (They can be seen as very fine traces in the copper by eye but they don't show up well on photos) Oh, ok. I didn't knowby MKSA - Delta Machines
Just went through this. This embedded strain gauge strained me to discover it ! Really smart indeed.by MKSA - Delta Machines
Quotedc42 With the extruder drive mounted directly on the effector, you need very little retraction and it doesn't need to be fast. So in this situation you can use a gear ratio much higher than 3:1. The remote direct drive extruders on the market use 30:1 and 40:1. Currently I use it on a Prusa and my aim is to get the extruder/hot end... as light as possible. The mass of such a gearbox made wiby MKSA - Delta Machines
Came across this thread looking for lightweight extruder. My current extruder/hot end etc mass is 220g (270g with carriage for a Geetech Prusa) made with gears and motor from an old HP Laserjet. I got this Nema 14 motor 14Ncm and without gears, its torque is just barely enough. I am looking for a 1/3 gear ratio that will allow the use of the lighter pancake Nema 14. The gear reduction of the cyby MKSA - Delta Machines
OK and how does these test cubes look at 60mm/s, 120mm/s and 180mm/s ?by MKSA - Mechanics
How do you measure the speed to be so sure ? Is it average, peak etc ??? PLA is the easiest to print. What about PETG ? I bet at this speed and with all these fans, the required T° and filament output won't be achieved.by MKSA - Mechanics
Looks like you have far more problems than just the part cooling fan ! And definitely the speed is NOT 300mm/s. It may look like it but that is because of the noise and the shaking , typical of these playful crappy chinese bearings that must grind the rods !by MKSA - Mechanics
Quotelkcl QuoteMKSA Always look at the big picture. Done. OK, now, what is the purpose again ? Usually it is one 30mm fan for the hot end, one blower fan for the part. SO ? one blower is nowhere near enough to deal with 250 to 300mm / sec or above print speeds. i'm getting perfect prints at 50mm/sec even with 50 to 55 degree overhangs. but with a square 20x20x20mm test cube running at 300mm /by MKSA - Mechanics
Always look at the big picture. Done. OK, now, what is the purpose again ? Usually it is one 30mm fan for the hot end, one blower fan for the part. SO ?by MKSA - Mechanics
Since I use PETG, I always have a drop of PETG on the bed at home position, or a dip if I remove it (the bed is covered with BuildTack) and sticking PETG at the nozzle ip. No problem with my modified Z switch mounted on the gantry even If I didn't preheat. How do you cope with this unless you clean everything every time ? I don't as it doesn't affect the printer in any way.by MKSA - General
For TR8 I print a bit undersized and finish with the leadscrew, heat gun while turning it with a drill. For a 6mm 1mm left pitch, too small to print and had no tap. I used the leadscrew as a tap (I filed the first cm accordingly) then same as for TR. Gives the right size and proper surface finish. Can't be achieved by just printing. Same for bushing, I used hand reamers too. Got to be careful witby MKSA - Mechanics
Leadscrews on X and Y don't really make sense for a 3D printer unless one use's high lead ones. These are not cheap. Yet the biggest issue it that leadscrews must be properly mounted and they must stay that way otherwise, they will bind.by MKSA - Prusa i3 and variants