Print starts in mid-air

[Billzilla]

Hi there.
I've had an UP 3D printer for a couple of years and really like it but it was time to get a unit with a larger print volume and having twin extruders is quite handy as well, so I got a Flashforge machine a week ago.
The test print of the supplied cube-like thing went perfectly, but when I try to print something of my own design the printer starts to squirt out a little plastic in the FL corner of the platform, then zips diagonally over to the RR corner, then goes off the edge and starts extruding into mid-air.
I've set the object in the centre of the platform, what have I missed?

[Geoff]

Hi there.
I've had an UP 3D printer for a couple of years and really like it but it was time to get a unit with a larger print volume and having twin extruders is quite handy as well, so I got a Flashforge machine a week ago.
The test print of the supplied cube-like thing went perfectly, but when I try to print something of my own design the printer starts to squirt out a little plastic in the FL corner of the platform, then zips diagonally over to the RR corner, then goes off the edge and starts extruding into mid-air.
I've set the object in the centre of the platform, what have I missed?

Hi Bill,

You have made sure its on the platform ?

Another possibility is often the model isn't watertight depending on what modelling software you used and how you used it. I know for me and Blender, before I print there is one step required to make the model printable, and that is run it through netfabb cloud.

https://modelrepair.azurewebsites.net/

Agh.. ive just checked and now microsoft run netfabb cloud so you need to sign in now to fix the model.

Upload your file to there it will send it back to you in an email with any holes fixed. What might be happening is the base layer is missing an edge, and Replicator G can't figure out the layer so it effectively leaves it out.

[Billzilla]

I'm pretty sure the model is fine, I drew it up in Autocad, have done that a few times with no problems on the UP.
Anyway I'm attaching it here, let me know how it goes.

[Geoff]

Ill try a small version for you, makerware sliced it no problem and the preview looked good so ill give it a go on replicator G. If you printed something out and it was ok like a cube, your z height is obviously fine, so it's a bit wierd. Illl let you know how it goes, ill give it a bash in the morning.

[Billzilla]

Thanks for that.

[Billzilla]

Apart from that, anyone got any other suggestions?

[Billzilla]

I think I might know now .....
I'm doing a print right now of a different part and it's working just fine. (though it scooped up a bunch of plastic when the extruder zipped from the corner of the platform to the middle. The small mound of goo is sitting on the edge of the raft but it otherwise seems fine)
I'll give that 1st part another try tomorrow and let you know.

[Billzilla]

Yep, it was my fault - I didn't save the file before printing.
It's now printing the part out perfectly, it'll be done in a couple of hours.
Thanks anyway!