mastory

This is not the behavior I experience. I am very much on the same page as @hoegge on this. It is very difficult to rotate a model and have it stay in view. Much less have the sensitivity it should have to zoom and rotate on fine details of the slice paths. Several times, the model and build plate has been tossed off into space to some unknown location where it can only be recovered by reloading. Is there, or should there be a 'view fit" button to reset? My feeling is that the pan and rotate inputs are resolved with very low resolution. EDIT Or maybe the pivot center is mistakenly at some distance from the model thereby exaggerating the inputs? This coming form a non-programmer, but very long term CAD user. No program I have used acts like Cura. The default pivot centering behavior is not predictable. I must say though that I have not experienced higher releases than 3.0.3. I am really happy to read that the new beta 3.2 has introduced orthographic views that shuld be a help for slice inspection. I should say that I have not had a problem rotating a part in reference to the build plate, only pan and rotating the overall view.

This page shows the blocks more assembled. https://ultimaker.com/en/resources/20910-align-print-head The screw goes thru the small block with a nut underneath. It would pay you to go thru the head alignment procedures to get your gantry nice and square from the start. The instructions do seem to skip over (or don't show it well) the part about inserting the small piece and clamping the belt. Maybe it's hidden in some other part of the instructions. No problem. For once a small mistake caused no harm and some stuff was learned. There are a lot of better alternatives out there for the slider blocks that can be printed. I like the "banana" variations. Although I have been interested in some of them, I have never made it a priority to print any of them as the originals are still satisfactory.

Look on the bottom of this page. Are your blocks like these? https://ultimaker.com/en/resources/20905-xy-axles

I can't seem to find a good picture of the slider blocks. Are yours made up of a stack of plywood pieces? If so, the center piece pivots and is meant to clamp into the belt, thereby adding tension. A screw captive in another piece pushes against the swiveling piece, locks the belt, and retains the tension. I think this area isn't assembled right causing your problems.

When you do remove the tape, be thorough when cleaning belts and pulleys.

The tape may be allowing slippage despite the fact the belt are tight.

I don't believe there's anything to gain from having tape on the pulleys. Have you figured out how the tensioners built into the slide blocks work? They are normally enough to get the machine functioning and often for a very long time.

If you feel the belts are tight by the descriptions given, don't over do it. I've heard of belts being stretched from use or more likely installed too tight. I think some people have attempted to improve backlash issues beyond diminishing returns by over tightening. You want them taunt, but not stretched.

Is the tape now removed from the pulleys? You'll want to get that taken out if not already. It's not part of a long term fix, and probably cause more issues down the road.

How much friction is in the gantry? If the machine is turned off, you should be able to move the print head around by grabbing it directly and it should take no more than a pound or two of force (and uniform) in any direction - the primary resistance is normally only the notchy feel of the stepper motor turning.. Perhaps your have a bad alignment of the gantry causing too much friction? or a tight bearing? If either, the motors could be losing steps, but this would be drastic and the should be audibly noticeable. It is easy to check. So both pulleys associated with the short belts have been tighten well? and also the primary drive pulley on each of the X and Y axis belt shafts? All the pulleys need to be tight really. Not so tight that you strip the screws or wrench. It really is a matter of feel that all mechanics learn by experience. I think the UM+ slider blocks are the same as on UMO. If so, there is a belt tensioner built into them although it leads a bit to be desired. However, mine are still in service after 5 years.

You could adjust your extrusion constant. This is a constant in your firmware, or gcode that relates to the mechanics of the filament drive. The correct value will cause the drive to feed accurately by length. It can be added to your start gcode if your printer is compatible. The code is M92 Exxx where xxx defines the constant. The correct value can be found by trial and error testing with Pronterface (printrun) console. Maybe yours needs a multiplier of 22 of whatever it is currently running. Search about fine tuning extrusion constant for more info...

For various reasons, every print has a prefered orientation on the build plate. Sometimes the reasons conflict each other. Choosing the best position to print in is key to getting the best print possible, reducing rework, etc

I model the bottom of holes as if they were drilled, but with a tip angle that is less than the support structure threshold angle. I'm not sure what the standard support angle is, but if were set to support anything lower than 40 degrees, model holes with a 90 degree or less inclusive angle. The slicer should not apply support inside the hole. Edit -- Per Kmanstudios response below, my comment assumes the holes are vertical and facing the print bed. Obviously, if horizontal, that technique won't help

Awesome. And thanks, but with that... I was just typing a reply to another topic, was informed that someone else had posted since I started writing. Was probably warned, but when I went to post, my post disappeared. Fortunately it was a short post. Is this the expected and preferred behavior?

How is the panning and zooming sensitivity in 3.1? I have a difficult time with the mouse inputs being hyper sensitive in 3.0.

+1 For mechanical design, perspective views are rarely turned on in CAD software. It is generally seen as a detriment for the kind of reason @pa9k mentioned. What would be nice are a set of hot keys that center and zoom the model/build area from each of the orthographic viewpoints.

I don't have a UM3, only a measly UMO. I thought maybe an UM3 power user would speak up. Some people are reporting problems with the site access, loading pages etc right now. Maybe that's an issue. It is hard to diagnose from one picture. From what I can see your problem may be with the extrusion mechanics. Since you asked about belts, I'll addressed that. They are straightforward to check and tension. If you still have problems after checking belts and pulleys, look into extrusion inconsistencies. Having looked at the model of the UM3 extruder, I am not comfortable coaching you how to maintain it. I would not personally be afraid to take it apart and check for problems. It depends on your mechanical confidence. What to check for would be loose set screws, clogged drive wheels, or that the spring is free to operate etc… Problems in the drive train though are often loosened set screws in the drive pulleys – especially on new machines. It’s not a bad idea to check them all. The UM3 3D model shows there are 11 pulleys. The 2 mounted to motors may be hard to reach, but you should be able to get to them without removing the inner covers. It could be possible that the belts have loosened on your new machine. It is as likely for the belts to have come loose on a new machine as one that has been in use. It is easy to check. If you suspect it, it should be investigated. The mechanics are in many ways the same between our units. I opened a 3D model of the UM3, and I can explain how to check the belts. If you have a belt tensioning issue with your UM3, it is more likely the short belts. The X & Y slider blocks on the UM3 have torsion springs built into them applying a constant tension which if assembled correctly and are confirmed to have worked they should not be a problem going forward. I cannot tell from the model exactly how the springs are assembled, but they are inside the slider blocks. One spring per long belt. Like I said, if you have a belt lash issue, it is most likely short belts connected to the motors. These belts link each of your X and Y motors to the rotary/linear shafting. The motors are mounted with screws in slots in the back of the print chamber and behind covers. The screws are outside the print chamber (4) for each motor. The belts should be snug, but not being stretched overly tight. It is hard to explain in concrete terms. Basically, it is a matter of feel. I would slightly slacken the mounting screws on each of the 2 motors, hold a moderate down pressure (2-3lbs?) on the motor and re-tighten the mounting screws. Check the belt feel again. Print something that won’t take a lot of time or material, but still tests your issue. If you want to check the long belts, pluck them like a guitar string with the print head parked in a corner. If the built in tensioners are working properly, they should make a quiet low pitch twang. Also, asses them by feel. You should be able to easily tell if they are overly loose. Another way to test is to hold one of the shafts at a pulley from turning (by hand not pliers or anything that would damage the shaft or pulley) and feel the backlash at the head by trying to shift it with the shaft held. Backlash should be minimal.

You may not have one on your system. It would only be there if you have previously either downloaded and/or configured it for upload to your printer. Configuration.h gets compiled in Arduino and the result is uploaded into your printer. If you've never messed with it, it probably doesn't exist on your PC. I'm no expert. If you wish to make changes, you'll need to research the best firmware for your needs, download the package and make your configuration.h edits starting there.

I just remembered that there were issues with the pictures moving over. Don't recall particulars. Wanted to bring it up in case it hadn't been considered.

Hopefully all the pictures in the existing forum will get migrated to the new forum. In the last transition, they weren't, and it was a huge loss for the community.

Unfortunately that drop-down menu is useless...99% of the time the "popup" vanishes when you move the mouse pointer down...making it impossible to select anything...yet another catch22... Ya, this has been iritating me for a long time. The function of the top menu bar is not intiutive. Mouse over and pause, submenus pop up only to disappear when attempting to select. Most of the time. Several attempts result in being allowed to select sub menus.

I added SSSDriver chips, and in the process needed to change some firmware options. I thought I would update to something newer. I tried the version on Bultimaker, with various issues, and have now switched to what I think is now Ultimaker stock for UMO and UMO+. After alot of "experimenting" I got the machine set up and completely functioning, except: Every print starts 10mm elevated off the bed. Printer homes correctly and performs my start Gcode correctly, and then moves the bed down to start printing in the air. Any ideas what I might have wrong? I don't have and Z height probe hardware. Thanks

You might like to check out this app https://bultimaker.bulles.eu

I'm re-onfiguring Marlin for my mildly modified UMO. None of the builders I could find address the aspects that make my machine unique, or provide a configiration.h file that I can further edit for my particularities. I've done some searching for my issues below without success. If anyone knows the following, your help will be greatly appreciated. I would like to backup my currently loaded firmware from the machine in case I mess up a new version. Possible? Are the end stop i/o inputs on the 1.5.7 board interupt capable? Newer branches of Marlin can take advantage of this if it can. Has anyone explored the Marlin feature called linear advance? It's billed as sort of like coasting, but better. Yes, @mechaneil, manually editing Marlin is a bit overwhelming. It's been a couple years since I did. The Marlin home page is a great reference. Matt

With your hot end being built up from new pieces, it would be a good idea to establish new PID parameters for your nozzle after everything is up and running. I would have to search up the method to run the test, and write the settings to the controller. It can be done by Gcode sent thru USB/Pronterface. That is how I did it.