SoliForum - 3D Printing Community — Help! Layers shift during printing.

Re: Help! Layers shift during printing.

2014-01-29T08:06:50Z

you can put fans on the m/b and steppers

Re: Help! Layers shift during printing.

2014-01-29T07:13:43Z

Wait a min. Does fan go on the stepper motor or the motherboard? I think I may have misread. I was thinking putting the heatsinks on the stepper motors themselves. Would that help? Or is it the mOtherboard that needs to be cooled? If the latter can I just buy a table fan and put it next to the mobo? Thanks

Re: Help! Layers shift during printing.

2014-01-29T06:20:58Z

no, don't splice into the wires that power the stepper, Hmmmm hadn't thought about the HBP... should work

Re: Help! Layers shift during printing.

2014-01-29T04:51:05Z

adrian wrote:

Photog wrote:
DigitalWhitewater wrote:
Also your stepper drivers might be overheating. Place a fan on them when you print.
Will a stick_ on heatsink work?
It will improve the situation, but its a magnitude below what any sort of active cooling will provide. The default currents for a SD3 mean that the controller really needs to be actively cooled when in use for any period of time in any sort of realistic ambient environment (if you can print in a 18°C AirCon controlled room, then you can probably get away without active cooling ). A heatsink might get you working to print one of the many fan covers available here or on thingiverse ...
The symptoms either way will drive you nuts long term and be entirely intermittent.. so if nothing else, taking the step of active cooling it means that you can rule out the issue in the future when trying to troubleshoot print quality issues.

if I get a 12v fan can I just splice it into the wires that are going to the stepper motor? If not what about the heatbed?

Re: Help! Layers shift during printing.

2014-01-28T08:07:14Z

Photog wrote:

DigitalWhitewater wrote:
Also your stepper drivers might be overheating. Place a fan on them when you print.
Will a stick_ on heatsink work?

It will improve the situation, but its a magnitude below what any sort of active cooling will provide. The default currents for a SD3 mean that the controller really needs to be actively cooled when in use for any period of time in any sort of realistic ambient environment (if you can print in a 18°C AirCon controlled room, then you can probably get away without active cooling ). A heatsink might get you working to print one of the many fan covers available here or on thingiverse ...

The symptoms either way will drive you nuts long term and be entirely intermittent.. so if nothing else, taking the step of active cooling it means that you can rule out the issue in the future when trying to troubleshoot print quality issues.

Re: Help! Layers shift during printing.

2014-01-28T07:53:25Z

DigitalWhitewater wrote:

Also your stepper drivers might be overheating. Place a fan on them when you print.

Will a stick_ on heatsink work?

Re: Help! Layers shift during printing.

2014-01-27T09:56:59Z

Also your stepper drivers might be overheating. Place a fan on them when you print.

Re: Help! Layers shift during printing.

2014-01-27T09:56:56Z

Also your stepper drivers might be overheating. Place a fan on them when you print.

Re: Help! Layers shift during printing.

2014-01-27T01:07:16Z

If the belts are not evenly tensioned and in sync(loosen one back pulley when tensioning) then they will fight each other and you can get missing steps and other problems.

Re: Help! Layers shift during printing.

2014-01-27T00:51:17Z

Both belts are loose but the left belt is exceptionally loose. What was that popping. Sounded like the belt skipping on the drive hub. Every-time the belt skips a tooth then you will loose a step and the part will be slanted.

Re: Help! Layers shift during printing.

2014-01-26T21:18:24Z

from the sounds of it it's not slipping, the belt sounds extremely tight...

but you can clearly see the left Y belt is not tensioned properly with respect to the right Y belt

Re: Help! Layers shift during printing.

2014-01-26T16:23:17Z

I did the extruder caliberation. It was overextruding by 15mm. I corrected it but the problem isnt solved yet.

It looks like a mechanical issue. The belts slip. Here is a link of the video. You can just watch the first 10-15 seconds and should see the belts slipping with a popping sound:

dropbox.com/sc/a3jiqby6kovvaty/QsoIodH4yN

Also, It always happens with this design in layers 7 and 8. Here is an image of initial stages when the layers starts to shift. If you zoom in you will see one side of the arc the supports are shifting but on the other its pretty much printed in the centre. I printed the same thing before so not sure why this problem would happen now.

Re: Help! Layers shift during printing.

2014-01-26T10:44:23Z

I would say that is a mechanical issue. The belts slipping, drive gear slipping on the shaft, stepper skipping from to low or to high of current. Do you hear anything abnormal, popping ect?

Re: Help! Layers shift during printing.

2014-01-25T17:19:06Z

It looks to me like the main problem is Z-height and bed level. First if your not printing on glass you should as your bed is probably not perfectly flat. This makes leveling difficult if not impossible.
Second squish your first layer more by adjusting your z Height. Also you can go into your slice settings and set your first layer height to a lower number like .3 if it's a .3 profile. it is probably at .35 I never understood that why that first layer height was set higher than the rest of the layers.

Re: Help! Layers shift during printing.

2014-01-25T16:48:55Z

Hi,

The settings could be seen in the snapshots from the repetier host. Anyways, the extruder temp was 198 and 196 in the two instances and the bed temperature was 85. I tried both 0.1mm and 0.3mm and the problems remained. I had printed good looking parts with these settings but have been recently having this issue with these arc like designs.

I did think about a partial clog so I cleared the clog in one of the instances when it was occurring by pausing the print and moving the extruder around. The clog issue was fixed and yeah it did drop straight. My concern is that the filament does not follow the radius that was given in the design. The first few layers are printed ok but as more and more layers are printed the layers keep shifting away from where its supposed to be. I have been mostly using the stock repetier host settings for speed with 50% speed for the first layer. Here is a snapshot of my slic3r settings for 0.3mm layers.

Thanks a lot for the help!