You have a pic of the cooling fan? what size is it?by n9jcv - Printing
I always download stls from thingiverse. I then import into sketchup, import not file open. Next i use a free plugin/e,tension from the warehouse called cleanup by thomtom or something like that. Cleanup will eliminate thousands of lines. Then i can usually do what i need. Some artifacts are left. Another handy plugin is available to make solid. I do have thoughts like the original posterby n9jcv - 3D Design tools
Yes, it is open source, everything is on the web to download and build your own. I was more curious to know if constructing that frame would make a huge improvement over an already good I3, not like an acrylic frame I3, but something better.by n9jcv - General
Either missed steps or a mechanical issue, slipping belts, pulleys, etc. Mark the pulleys and shaft to ensure they are not slipping. You could probably up the voltage a bit on the missing axis if the motor and driver are not too hot. What kind of printed? If i3 is that your Y axis that it skipped on?by n9jcv - Reprappers
Also, it could be that the motor coils are shorted out, because you have all the wires bundled up. If the wires touch the coils short and then it is very hard to move the steps. Separate all the wires and you may find it moves easily. If all wires are NOT touching, then perhaps the belts are too tight.by n9jcv - Reprappers
So, I have been looking at the Lulzbot Taz 6. It seems to me that is is really just an Prusa I3. It has 2 motors that drive Z leadscrews, the same X Carriage belt driven and two z rods as well. The bed moves in the Y direction on 2 rods as well and is belt driven. Seems to be the same to me, but one difference. It has a very rigid frame built around the Z and X. So is it really just a Prusaby n9jcv - General
It appears you do not have a print cooling fan, when layers extend out/overhang, you need a print cooling fan, and you probably need to slow the printing down a bitby n9jcv - Printing
In my case I don't think the belt tension is enough to flex the 2020 extrusion, but if so, I have not noticed. As far as the bed falling, I only print when I am near the machine, that said, I could still have a power outage. I have not figured this out yet. Sometimes when I turn off the power, the motors are still engaged and the bed drifts very slowly to the bottom, as if the z motor is actinby n9jcv - CoreXY Machines
Thanks for all the help and suggestions. I went with a Z axis powered by a single motor, with 2 belts kept in sync by a 8mm rod and pulleys, and a short loop pulley to the motor. Very similar to DD's design, although less metal. My bed is very stable and accurate and there is NO noticable bounce at all on the bed!! Some pics of my solution. also on thingiverse I posted all my parts forby n9jcv - CoreXY Machines
Very nice metal working. I can already tell your finished product will be great. Nice trick with the shim for the offset bushing!by n9jcv - CoreXY Machines
probably a combination of things, First the stringing is from not quite enough retraction, but the stringing is really a minor issue. It appears you are over extruding. Meaning you are pushing too much plastic. Have you calibrated your extruder? You really need to do that. Also the tops of the object appear to come up in the corners, I would bet you need to reduce temp just a bit and you shoby n9jcv - Prusa i3 and variants
I don't want to hijack thread, But Andy can you expand on the MPCNC please? Is it this? MPCNC Did I understand you correctly you are cutting aluminum with this? What is your spindle a dewalt 660? Thanksby n9jcv - CoreXY Machines
there is always the option to use 3dhubs to get your parts printed, may be cheaper then you don't have to know anything about how a printer works, you only need to send a file of the part you need, you could have 50 made and sent to your house in a week, probably cheaper as wellby n9jcv - General
thanks that 2nd pic is pretty coolby n9jcv - CoreXY Machines
So I have been looking and thinking and stumbled on this Seems like a good solution, easy and does not require a lot of extra parts or over engineering. What are your thoughts on that? Seems like I would not have to worry about bouncing. And comments at thingiverse suggest there is not any issue with slop or wobble, like the tilting bed issue I experienced.by n9jcv - CoreXY Machines
so have others just ignored this problem and printed with this tilting/slop? I observer the t8 nut very closely and that is the cantilever point and the nut itself rocks side to side, if that were rock solid, then there would not be this issue, but I realize play is necessary for smooth movement. what is my best option for a stable bed, using 1 or 2 z steppers and 2 smooth rods, is there a goodby n9jcv - CoreXY Machines
So, I think I found a simple solution, but I am not sure why it works. I had the long side of the T8 nut facing up, to maximize my lowest z position. I now have the long side pointing down and 90% of the tilt is gone. It would seem to me that the bed weight would be the same on the T8 nut regardless of which direction it faces??? Strange So that was not the problem, I think at this point theby n9jcv - General
So, I think I found a simple solution, but I am not sure why it works. I had the long side of the T8 nut facing up, to maximize my lowest z position. I now have the long side pointing down and 90% of the tilt is gone. It would seem to me that the bed weight would be the same on the T8 nut regardless of which direction it faces??? Strange So that was not the problem, I think at this point theby n9jcv - CoreXY Machines
Here is a pic at any given point at z, the bed will tilt with even slight pressure. There are no zip ties, and again i checked, if you grab the purple bearing holder you can not move it in the x or y direction.by n9jcv - General
Here is a pic of the current configuration And also the side to side tilt seems to come from the slop/backlash (side to side) in the T8 nut. The slop of the nut in the front to back plane is basically eliminated due to the weight being on the front side of the T8 lead screw.by n9jcv - CoreXY Machines
I have a similar post in General, but did not get much traction there, I should have put it here I guess sorry Anyway, the issue I have with a corexy I am building is this; I have a cantilever bed, 2 smooth rods and LMLUU bearings and 1 t8 lead screw, in the rear, the t8 lead screw is centered. I have the frame for the heatbed, but no heatbed attached yet. The frame will not move in the xby n9jcv - CoreXY Machines
Origamib thanks for the suggestions. Let me provide some more detail. At this point I do not have the mk3 installed, just the frame for the bed. I double checked and there is NO movement side to side or back to back with the frame x or y. The movement is in the z direction. In the center z movement/slop is very tiny. But at the left or right rear bearing, the z movement can be up to 2 mm.by n9jcv - General
maybe an idea, from Digital Dentist in another post "The biggest problem with cantilevered beds is that the edge opposite the side with the guide rails tends to bounce when the XY mechanism is flying around causing the machine to shake. Flexibility of the guide rails, the printer's frame, and the cantilever itself all contribute. If you put a lead screw or two under that floppy edge the bouncingby n9jcv - General
Been looking all over, not sure I have any solutions yet. I have 4 lead screws and nuts and they all have the same amount of backlash. So, thinking, maybe just go to 5mm threaded rod and a nut, still backlash, but not nearly as stiff and maybe the bed will be enough to counter it? Thinking maybe use a belt for the z, maybe no backlash? As I said right now this is a cantilever bed, 2 smoothby n9jcv - General
I am working on a new printer. It is a corexy with a single lead screw. I am finding that the bed will tilt side to side due to the slop in the nut for the T8 leadscrew. I am wondering if there are any easy ways to deal with this issue. Has anyone else solved this? Thanksby n9jcv - General
I am not an engineer and have no metal working experience, thus the questions. If I were to have metal parts made by a CNC shop, at the cheapest rate, what tolerance could I expect. For example, if my file calls for a 5mm hole, what would be acceptable 4.8 -5.2mm?? Again, I have no idea of what is typical. If designing a hole, that is supposed to have a rod go thru it, but be held tightly, lby n9jcv - General
Sigxcpu, thank you, I think I understand now, and even if I calibrated the steps differently it would not work as it is not constant, it is the sine, which would vary so you would be unable to calibrate the number of steps as a constant. I hope I understand it properly now, thanks againby n9jcv - CoreXY Machines
Thanks for the help, so a few more questions. 1) I am just taking some/most of this from FB2020 corexy design. It shows a twist in the belts. On an I3 and on a delta I ran the ribbed belts on 625 bearings, and never had a problem with the ribs on the bearings. Never needed to twist a belt to get the flat side of the belt on the pulley. So can the same be done with corexy, even though thereby n9jcv - CoreXY Machines
I am working on modding/creating a Corexy. I have read about the corexy kinematcs, but I am not sure I really understand all of it. Anyway, I am thinking to modify the belt path to look like the drawing below. The standard belt path is blue and red. I am wanting to modify the red path and the blue path both to move just the motors. They would then follow the purple path. There would still bby n9jcv - CoreXY Machines
Ax, one more question, the y carrier left and right, they have a 5mm hole for the bolt to hold the bearings, but there is no nut on the bottom, but the hole appears to be roughly 1/3 filled at the bottom. Is the idea that the bolt will thread into that plastic to stay in place? Thanks bby n9jcv - CoreXY Machines