CTC: Nozzle off the build plate during levelling

Jacopo_2 · 2017-02-06T19:12:57.000Z

Hello,

I just bought a CTC 3d Printer (Markerbot clone) and when I level the build plate and have the printer move the extruder to the 4 positions, when it’s supposed to move it towards me the nozzle is out of the build plate, so I cannot level it in that position

It looks as if the build plate was too small or offset by an amount towards the back of the printer

How can I solve this issue?

D3DI · 2017-02-07T09:41:56.000Z

My nozzle moves to a position which looks like it moves of the back of the build plate but in actual fact it is just very very close to the edge. Does your nozzle actually float all the way off the plate? Is the opposite position way off too, i.e. further into the build plate?

Jacopo_2 · 2017-02-07T10:02:03.000Z

Yes, the nozzle is outside of the build plate, no levelling possible in that position

one explanation I could have is that the y limit switch is not where it should be

the two screws that connect it to the frame are not aligned (the top one is not exactly above the other but it is offset by 3mm towards me) so the y ‘home’ could be offset as well

Is this the case on the other printers or is it just mine?

wirlybird · 2017-02-07T12:19:04.000Z

Sounds like a good starting point. You might be able to google for pics of other machines to see.

Jacopo_2 · 2017-02-07T13:05:16.000Z

I can’t find any

can anybody check his own one?

uniquesoftware · 2017-02-07T14:50:10.000Z

Your homing settings are probably off with the nozzle offset. This happens whenever you upgrade the CTC to Sailfish, for example. Try to reset EEPROM to factory settings in your utilities. Hope that helps!

D3DI · 2017-02-07T14:52:40.000Z

I have two CTC printers. 1 of the printers y-axis limit switch is indeed at an angle whereas on the other printer it is almost straight. I will take some photos when I have re-charged my phone a bit. Could you send some images of your printer?

You could try loosening the nuts on your limit switch and pulling the switch assembly towards the front as far as it will travel before re-tightening!? Or add a temporary bit of blue-tac to the carriage so that the switch is pressed sooner. Just to get it up and running.

I would also check over the whole printer for signs of build errors such as nuts/washers trapped between parts by accident or missing bolts etc…

Another thing you could check is if the bed levelling screws are fully extended, perhaps that is causing the bed to be pulled to one side. You could try levelling the bed to the best you can and see if the issue diminishes/gets worse/stays same.

I hope you get it up and running soon. Both my CTC printers worked out of the box and both looked like they had been tested before dispatch. When I home the bed the nozzle does appear to be off the bed however, it is very close to it.

Jacopo_2 · 2017-02-07T15:33:29.000Z

Thank you very much

The pictures of your printers would help a lot

I’ve designed a part to offset the switch towards the back of the printer (will post a photo this afternoon)

the blue tac thing would make things worse because it would offset the home position in the wring direction

uniquesoftware · 2017-02-07T16:56:05.000Z

Is this the pic you need? We’ve got 4 CTCs so just let me know which shots. Best of luck!

ctc-y-axis.jpg4048×3036 3.59 MB

D3DI · 2017-02-07T17:08:13.000Z

Sorry they are not the best photos ever.

printer_1_0.jpg1152×2048 435 KB

printer_2.jpg1152×2048 522 KB

Jacopo_2 · 2017-02-07T18:09:47.000Z

This is mine

image_192.jpg3024×4032 1.32 MB

Jacopo_2 · 2017-02-07T18:14:56.000Z

Sorry, the picture is rotated, but I think it gives the idea

I tried removing one screw and keeping the switch straigh; I now have just enough room to perform the levelling in all the points. even though there is very little space between the nozzle and the end of the build plate