Prime Tower Geometry Change?

[Rossboss 0]

I'm currently nearing the end of a 2 day, close to full height build on an UM3 and the prime tower finally decided to give way after looking pretty shaky for the last 8 hours or so. I've got about an hour left of pulling filament out of the nozzle at the end of each "ghost" layer of the prime tower as to hopefully let the build finish successfully.

Anyway, the prime tower was already 20mm in size and I dont really have any desire to go up any further if I dont have to. So instead of enlarging the cross section, is there a way to change the prime tower geometry? For instance is there a way to change the Gcode to print a hollow square tube with wall thickness x that is 30mm or 40 mm instead of a solid square pillar? I have no familiarity with gcode so I have no idea.

Thanks!

[gr5 2,172]

Well I recommend adding your own prime towers before adding your model (so they print before the model) to help hold it together and you can make the bottom wider and stronger and the top smaller/skinier. I added 2 towers - one of PLA and one of PVA:

[gr5 2,172]

In addition it's common for that back right corner to be lower on the glass - the glass or the aluminum under it can be warped down. So before you start another print check your glass with a straight edge or ruler and if the back right corner is lower then try removing the glass and bending up the aluminum bed or move the prime tower to the rear center.

[Rossboss 0]

 

@gr5 so what i'm hearing you say is add your own stl model that will act as a prime tower and then upload it first so that the tower is printed first each layer. Is that true 100% of the time? First model uploaded is printed first? seems like it could be inefficient depending on your layout.

[neotko 1,417]

The object close to the tower, is printed first after the real tower. Ofc if the real object has a Y closer to the bottom than the prime tower, then you need to readjust so you keep controlling the hierarchy. Inefficient on material use and time yeah, but can save a print sometimes.

[zerspaner_gerd 382]

change the Gcode to print a hollow square tube with wall thickness x that is 30mm or 40 mm instead of a solid square pillar? I have no familiarity with gcode so I have no idea.

Cura 2.4 Beta is here!

[gr5 2,172]

In Cura 2.3.0 you have to place your own towers before the model to get it to print your own towers first. But in Cura 2.4 beta I believe I saw mention of control of print order. I haven't played with that feature yet.

In addition I used the existing prime tower. Not sure that made sense - to use the built in prime tower. I placed my towers as close as possible to the cura prime tower without touching it to help hold it up.

[gr5 2,172]

But more important than all that is to get it to squish better in the back corner. Check your glass with a ruler. I think you will be very unhappy but it's not hard to fix.