I recently upscaled my 4800 with +200mm on Z-axis and bored up the nozzle to 0.9mm. The souped up Vertex looks (and ran) as sweet as can be!
After fine-tuning for some weeks we printed without any major problems. The print result was beautiful.
Since a week the printer goes roque on the X-Y and Z axis. The printhead makes one random shift on the X or Y (or both at same time) and continues printing. Now and then, in this random head-shift, it keeps on moving the head ending up colliding. This same thing happens with the Z-axis now and then. Moving the bed up ending up in a collision, or moving the bed all the way down ending up in a collision. My print job takes 5 hours and it happens somewhere around halfway or in the end :(. The rest of the print job is as steady as can be, until this ‘bug’ all of a sudden pops up.
I checked the belt tension, cleaned the IR endstops and aligned and redid the X and Y axis.
This problem happens both printing from SD and from the computer.
I uploaded the latest firmware and redid the eprom settings as requested.
From the startup I use Cura on the Mac.
To be honest, i am now clueless.
Who can help me out? Any suggestions form the Velleman R&D guys?
This is usually down to incorrect belt tension. The steppers can only ‘skip’ if they meet resistance, therefore something must be causing resistance. Did you try removing the belts and move the head in both directions to check the rods are parallel and there is absolutely no resistance? If this is the case, then try reassembling the belts as loosely as you can (don’t do the clamps all the way) and check again.
However, I’m not sure what could cause the colliding. The IR stops should always work, regardless of where the firmware thinks the head is. So I’m a bit puzzle by that one, particularly given the fact it’s happening on all axis. So when you click the home icon, the Z and XY axis home correctly, or collide, or collide intermittently?
I encountered the same problem and tried to realign axes and adjust belt tensions.
Then, I lowered the maximum speed and acceleration of the motors.
Still no solution. Finally, I got everything working well with all of the above and frequent lubrication of all six metal rods.
Especially applying some extra oil to the rods seemed to help massively
[quote=“ddumon”]Especially applying some extra oil to the rods seemed to help massively[/quote]Clean the rods on a regular basis. Oil+dust = thick paste blocking the axis.
Thanks for these suggestions guys.
Homing on the endstops works without a problem. i re-alligned the axis and cleaned and re oiled the whole thing. Belt tention is looser now and still i get these collisions on x/y/ and z. Note, when colliding on x and y the head hits opposite of endstops. And when colliding on ‘z’ the bed moves all the way down, away from the endstop (or up and colliding on the half finished print job.
Still stuck and puzzled (since al went well the first ±15 print jobs.
Exactly! Everything runs smooth the first half of the job (total print job ± 5 hours). Then all of a sudden the printhead moves away to the front-left (away from the IR endstops) where it collides. Or the bed moves in one direction until it collides. This happens randomly somewhere in the second half of the job after which we need to reset the printer resulting in a worthless unfinished print.
I print from computer (mac+Cura) and I print from SD. Both resulting in this same situation.
I just assembled my k8400 and are doing dry runs and I can see shifting happening (I don’t have 1,75mm filament yet, delivery in 2 days).
I have no idea yet how to adjust the rods, so they become parallel, as there are no adjustment in X and Y relation between same axis rods. There are no mechanism to tighten the belts either, but I guess that’s described somewhere or elsewhere in the forum.
I believe that the motor boards are overheating just as they did on the k8200. They get really warm when I do dry runs now and will install heat sink’s on the chip surface. Worked well on the k8200.
You apply 3M or similar tape, that are able to transfer the heat onto heat sink. I use aluminum 6mm x 6mm heat sinks 10mm tall with two fins. Maybe install a fan on top if needed.
You can get heat sinks from something like frozencpu etc.
[quote=“MagnusT”]I have no idea yet how to adjust the rods, so they become parallel, as there are no adjustment in X and Y relation between same axis rods. [/quote]You can begin reading [color=#408040]this[/color].
I have it all tuned in right fine right now. I have a hard time with the BuildTak, I simply cant get filament spill of it and need to chisel things of the print bed. Issues with lifting in edges too, so I will install a MK 3 aluminum heat bed.
I’m still interested in hearing of thermal cooling fins helps any of these issues.
I am now cooling the board with a big cooling fan almost on top op the drivers (no heat sinks yet). Stil no progression ending up in this colliding issue somewhere halfway the job.
I wil do a complete re-tuning of the rods soon, hoping this wil help…
I wil post the result for you guys.
So how about the Velleman team… Do they have any other suggestions that might help me?
ok, sorry to hear that. Would have been an easy fix. Do you have any idea of the temp of the chips before and after? Of so we can compare it to my heat fin temp. I have not had shifting issues after I adjusted everything to remove resistant in the X-Y axis as much as I could.
X/Y must be as friction less as ever possible. This deservers crosschecking and triple checking. Its vital for good prints, that the motors only have to move the head and not friction elsewhere.
I use a $ 20 laser heat temperature measuring device
The problems as described above are now solved and we caused by tight belt tension. As I upgraded my machine I milled custom body panels. The bearing-slots were slightly out of position. The distance between the outer rods are slightly bigger than original.
I re-alighned al rods and removed some plastic from the belt clamps resulting in way smoother handling.