Ultimaker 3 Extended crashes badly at the start of bed levelling procedure

[Tavs 0]

Hi All

 

My Ultimaker 3 crashes at the start of bed levelling procedure. The printer starts up ok but as soon as the head starts to move towards the centre for the bed checking/levelling procedure it crashes badly, meaning complete shut down with power loss. I can move the bed up and down fine and there is no problem with charging filament. I have also have carried out the axis speed test - which was also fine. I have done a factory reset and also updated to the latest firmware. I would be really grateful for any ideas on what could be wrong.

 

Cheers

 

Tavs

 

[MariMakes 198]

Hey @Tavs,

 

Welcome to the Ultimaker Community 🎉

Wow, that sounds good. 😕

Can you test the limit switches for me?

If these work, than there might be a broken part somewhere. 

Then it's better to reach out to our support experts.

You can create a ticket here: 

https://support.ultimaker.com/hc/en-us/requests/new?ticket_form_id=360000516360

[Tavs 0]

Hi Marimakers 

 

Thank you so much for your reply. I have just run the limit switch test and it shows constant contact (X) on the Z in the home position, with X and Y registering an X when I press them manually - I presume that is all correct?  

 

Cheers

 

Tavs

 

[gr5 2,167]

I'ts important to lift the bed up when you do this test.  You can just pull it up.  Firmly gripping towards the rear of the bed.

 

The amount of force to get it started is almost the amount of force needed to lift the printer so don't hurt your back.

 

Also look under the bed and you will see this long screw sticking down and look at the hole it sticks down into.  Often a piece of plastic (from earlier printing) is in that hole messing things up.

[gr5 2,167]

Your power brick is probably weak.  The power brick is sophisticated and has it's own computer.  It monitors the voltage and such and will shutdown if it is unhappy with anything.  I believe the UM3 comes with this power supply part number:

 

GST220A24-R7B

 

There is another version of this supply without the "T" in "GST":

GS220A24-R7B

 

Both versions of these power supplies can age or have "infancy failure" (meaning it dies within the first week or so) and it's quite common for these supplies to no longer put out the current/power they were capable of initially.

 

I prefer the GS version as those consistently put out more power.  Ultimaker prefers GST (if I remember right - it's because it meets more safety requirements and is probably mandatory for the CE certification - but my memory sucks on this point).

 

Anyway you can buy either version as a standalone part.  There are probably good deals on ebay.  The last I checked (probably 5 years ago) it was about 95 euros for either version.  For a new one (not used).

 

I have to tell you that your description of the issue is very critical.  It might be better if you showed a video.  But if it powers down before the print head reaches either end and the printer reboots then it's probably the power brick.

 

Also try pushing the print head around yourself to make sure there isn't double the friction on one axis versus the other.  X and Y should be similar resistance.

[Tavs 0]

Hi gr5

Many thanks for your suggestions, I have lifted the build plate during the limit switch test as you suggest, that all seem fine and the switch disengages correctly. There doesn't seem to be any plastic waste in or around the switch. The axis move fine and I have oiled them again to ensure smooth operation. I  

I taken a video of the issue but I can seem to attach movie files to messages in this forum? Weirdly it also seem to happen at the particular point of the cycle, I guess it might the be power supply, but there doesn't seem to be any issues with heating the nozzles which would draw more power - could it be the main board?

 

Cheers

 

Tavs

 

 

[gr5 2,167]

The main heater is about 150 watts (maximum).  The nozzle is about 30 watts.  The 4 steppers total about 40 watts (if I remember right).  That last bit is what puts things over the edge.  The wattage needed is similar to what the power brick can put out.  Just a little bit less.  Some power bricks can't quite do everything at once (bed heater, nozzle heater, steppers).

 

Does that make more sense to you?

 

One way to lower the power is backwards from what you might think:  Set the bed temp to a higher value.  At 100C, the bed resistance goes up so it draws less (maximum) power and sometimes that will be just low enough that the power supply is happy.  However if you are printing almost anything but nylon or ABS, then 100C is much too hot for a successful print.

 

Alternatively you can set the bed temp to 0C and use blue painters tape (washed in isoprpoly or ethyl alcohol first to remove the wax).  This can help provide evidence if the problem is the power brick or not.

[Tavs 0]

Hi gr5

 

Thanks again! I think you might be right on the power brick, I have turned off the heated bed and could get the print started. Will check again when I get back from work. 

 

Cheers

 

Tavs