Support material shifting while the print is OK

[Timini 0]

Hello,

 

I now have a very strange situation that I'd like to solve. I'm printing a fairly large piece, a handle for a very heavy electric unicycle.

 

Here's the expected result with the gcode

Here's the first layer according to the gcode:

 

Everything seems normal here.

However when I go to print it, the first layer looks like this:

 

The rest of the printed object went as expected. Even reslicing, updating the fw of the printer (alfawise U20, a CR10 clone) does nothing. I have this printer for nearly 6 years and never gave me any issues before...

If I reposition the print 180° along the z axis, it goes like this :



 

It still shifts, but only one of them in another direction...

I tried everything but can't make it work. The gcode and stl are her at the end.

Thank you very much for your much needed help,

 

Tim

AU20_begode_master_handle.gcodebegode_master_handle.stl

[Slashee_the_Cow 382]

If you could share the Cura project file (.3mf, in Cura get it set up then go to File > Save Project) that might help us figure out the problem.

 

Looking at the gcode preview in Cura the first thing I notice is that I can't see any skirt, even though it's supposed to be printing one. I can see the nose wipe but not the skirt:

And the second thing I notice is that while the two sides seem symmetrical, on one side the support has a bit jutting out:

 

If I load the STL and slice it for my printer then load the gcode preview, things look pretty normal:

The first thing I noticed is that holey shirt that thing is big and yes I realise an E3V3SE is not a huge printer.

The second thing I noticed is that I can see the skirt fine.

The third thing I noticed is that the support still has a bit jutting out on the same side:

 

Looking at the STL file itself it seems both symmetrical and to have far too many tris in some areas, but that's symmetrical too so it shouldn't be making a difference.

 

Suggestion (other than sharing your project file so that we can play with settings): try tree supports. I ❤️ tree supports even if they're not really designed for this sort of thing... but hey, if they work, that bit doesn't really matter.

[Timini 0]

Hello,

I don't print any support, including skirt, so that's why 🙂
Thank you very much for your analysis and the time you take to help me 🙂

AU20_begode_master_handle.3mf
Here's the file you asked

[Slashee_the_Cow 382]

1 hour ago, Timini said:

I don't print any support, including skirt, so that's why 🙂

There's a skirt in the gcode file though 😕 

*/me thinks for a minute*

*/me looks at coordinates in gcode file and thinks for another minute*

Ah, it's the support brim. Never mind.

 

Interesting... if you rotate it so that it's facing along the X axis (either way), it does the jutting out bits on both sides:

But on the Y axis it's only on the right. And whatever way around it's rotated, the gcode still looks like it should print fine.

 

So my first suggestion (and yes it is a serious suggestion) is to try using trees. If it's a completely different support type maybe it'll act completely differently... which in this case sounds like it would be "acting normal".

Trees just have the problem of wanting to fill these holes despite the fact that they don't have LoS to the build plate:

Nothing a couple of support blockers can't fix though:

Here's that one where I set up the trees and support blockers if you want to try: AU20_begode_master_handle_trees_blockers.3mf

 

Other than that I would suggest rotating it 90° so it faces along the X axis and you'll see the little bits which I still can't explain on both sides:

And after you rotate it, open the move tool with the model selected and make sure it's at 0, 0, 0.

 

2 hours ago, Timini said:

a handle for a very heavy electric unicycle

I would say that I'm jealous you have an electric unicycle, but... I'm jealous you can ride a unicycle at all 😮

Might be the awesome technicality one would need to get around with electric power around here though. In this state you have to ride bikes on the road but e-bikes are limited to a maximum speed that the motor can get you up to (you can pedal faster if you want... and if you can) which is lower than the speed limit on almost all roads so wouldn't exactly make me feel warm and cosy and safe, and e-scooters are banned in public areas because they're too much of a vehicle for the footpath but not enough of a vehicle for the road.

[Torgeir 250]

Hi @Timini,

 

Interesting to see a practical device 3d designed and ready to be printed. 🙂 

As PLA may/will be very brittle in short time, -you may consider a stronger material as PETG or even Nylon.

Cura 5.6 had some issues, a much better version are the last version -Cura 5.71..

 

Good Luck.

Torgeir

[Timini 0]

Wow thank you so much for your help, I'm currently printing it in a strange position without support and it works fine, but it won't be in the correct position to withstand the force I'll apply to it...I will try what you suggest

Where do you live ? Technically, here in France, it is legal up to 25 km/h, but it is kinda dangerous to drive that slow in the traffic, so people do what they have to do... Riding an EUC is really not a big deal, you'll swear a lot the first 2 hours, but once you taste it, there's nothing like it...

Tim 🙂

[Slashee_the_Cow 382]

23 minutes ago, Timini said:

Where do you live ? Technically, here in France, it is legal up to 25 km/h, but it is kinda dangerous to drive that slow in the traffic, so people do what they have to do...

I'm in the down underverse. Not sure about other states but here, on an e-bike, it's only allowed to go up to 6km/h if you're not pedalling. If you are pedalling, above 6km/h the power output has to gradually go down (so you do more of the work) until you reach 25km/h, at which point the motor has to cut out entirely.

 

Pedal assist bikes don't have a speed limit where the motor cuts out but they can't move without you pedalling, and aren't allowed to have very powerful motors. Also legally they have to have a height adjustable seat 🤔

 

34 minutes ago, Timini said:

Riding an EUC is really not a big deal, you'll swear a lot the first 2 hours, but once you taste it, there's nothing like it...

I'm pretty sure if I tried it I'd be tasting the ground for well over two hours 🤕 but given the opportunity and a well padded room it's something I'd definitely be curious enough to try.

(Story time: I learned to ride an bike without training wheels, but it involved things like going slowly while my dad ran beside me holding me up. One time doing that he'd let go and I didn't realise, and as soon as he shouted with encouragement that I was doing it, I promptly fell over.)