3D printing forums

Hi all, Using different brands of PLA that run at different temperatures on a UM2 with an Olsson block/2+ upgrade. As there is no way to change temperature in Cura ( the Ultimaker draws on the values in it's config file,) I created a custom printer in Cura.   I am looking to block out the corners of the build plate to avoid the nozzle hitting the bed clips.  Ideally adding this to the Start G-code, assuming I can do this without manually editing the fdmprinter.def.json file   I did find this, which was promising. https://files.fieldofview.com/cura/Replacement_Patterns.html   I can change the nozzle temp using this syntax, but couldn't find a syntax on how to clip out the corners of the build plate A 1hr google did not show syntax - tried the Reprap forums also as well.     Could anybody point me in the right direction for this syntax?   Regards,   A   ps:   FWIW, the below is the custom Start G-code to allow custom temperature setting  in Cura on an Ultimaker and produce a prime blob on a 0.25mm nozzle as well as a nozzle wipe.  For a 0.4mm nozzle, I'd increase the E values by 16/6.25 ~250%.  Not a perfect blob, but good enough to prime it.   M82 ;absolute extrusion mode G28 ;Home M190 S{material_bed_temperature_layer_0} M109 S{material_print_temperature_layer_0} G1 Z15.0 F6000 ;Move the platform down 15mm ;Prime the extruder G0 X0 Y10 Z0.5 G92 E0 G1 F300 G1 E4 Z2 F4000 G0 F300 G4 S5 G0 Z8 F300 G4 S5 G0 X0 Y30 F2000 G0 Z 0.15 G1 X0 Y200 E8 G0 X0.4 Y200 G1 X0.4 Y30 E8    

Thanks, Solved the problem with this link https://support.makerbot.com/s/article/1667412437627   That goes together with your proposal. Setting should be changed from windows instead of doing it form AMD catalyst software.    Thanks again and take care

Exactly. Its a really strange adjustment thats been made to the prime towersin 5.7. When using a tall prime tower and printing with TPU (where there is a lot of excess ooze that gets caught on the prime tower) the stress exerted on the tower after around 80mm becomes too much and it fails. It has failed with PLA on large towers a few times for me but it fails almost every time with TPU. This is a pretty massive oversight imo. I love 5.7 but I think I am going to have to go back to a previous cura rev. Im trying to get prototypes for work done with TPU and with the prime towers failing if im printing anything over 80mm. And its leaving me with some ugly prints. @GregValiant

Maybe @Dustin can explain.  Here is what I see:   This is the first layer of an "Interleaved" prime tower with a brim.  There is no actual prime tower, just a brim.  The same thing happens with a skirt.  The Prime Tower doesn't actually connect to the bed.   The first layer of the actual tower goes down on layer 2 so the base of the actual Prime Tower is under-extruded by around 50%.  It doesn't really connect to anything.   This is the first layer of a "Normal" prime tower.  This sure looks "Interleaved" to me, and there is very little contact area with the bed.  As the tower grows, this weak point gets stressed more when the nozzle comes across and makes contact.   Also in regards to a "normal" tower, every other layer is "interleaved" and so there is poor layer adhesion on those layers.

How can I check that? If it's not, how can I fix it?