Build surface advice
Posted: December 8th, 2016, 8:40 pm
Hello all
I've tried a couple of different build surfaces and I get issues with each. My aluminium heated bed is warped, and from what I can gather this is quite common with aluminium plates. I'm interested in hearing the advice of others on what they have found to work well on their printers; I'll detail my experiences below.
Heated aluminium build plate lined with masking tape:
Excellent adhesion, but some issues with under-extrusion: the warp in the bed brings the nozzle too close to the bed and the nozzle gets blocked.
Heated aluminium build plate with no liner:
Pretty much unusable. When I properly level the bed, the nozzle will hit the build plate when moving across the X-axis (the plate appears to be warped upwards along the centre of the Y-axis). Lots of extrusion problems due to the nozzle being too close to the warped part of the bed.
Heated aluminium plate with borosilicate glass build surface:
Very flat surface, so I get perfect bed leveling. But... the glass is 200x300mm and my alu plate is 220x275mm, and all of my prints lift. From what I gather this is due to the temperature differential: glass absorbs heat very well, so the lower layers are warmer and more pliable than the upper layers: et voila, printed items lift. I get the best results with this method so far (see these examples - sorry for the facebook links! https://i.imgur.com/Kqg0Rgb.jpg https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58B5CF99 https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58F481E8 https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58B83843)
Un-heated aluminium build plate lined with masking tape:
Not tried.
Un-heated aluminium plate with borosilicate glass build surface:
Not tried.
Un-heated aluminium plate with borosilicate glass build surface lined with glue stick (or some other material):
Not tried.
I've also tried an inductive Z-probe so that I can use automatic mesh bed leveling. That's currently on hold because the sensor I bought appears to be knackered and the seller is being really fussy about refunds/returns (the sensor accepts 6v-12v; the output should be 0v when not triggered and the same as the supply voltage when triggered - my sensor reads 6v out (on a 12v supply) when not triggered and 4.7v when triggered). I can trigger the Z-min input when I hook it up to my bench power supply and feed in 5v, but the sensor itself appears to be knackered.
Based on everything I've learned so far, my best bet seems to be an inductive sensor and mesh bed leveling. That should allow me to use the bare aluminium heated bed and have the software compensate for the warp in the bed. While I shout at some useless seller about a replacement sensor (I'm not buying a new one, I begrudge paying out of my own pocket for a faulty item) there are still quite a few things I'd like to print. I'd be keen to hear any advice people might have on build surfaces.
FYI: I print PLA at 205°C with the bed set to 50°C (60°C first layer); I usually use a layer height of 0.2mm. I can post my Slic3r settings if needed.
I've tried a couple of different build surfaces and I get issues with each. My aluminium heated bed is warped, and from what I can gather this is quite common with aluminium plates. I'm interested in hearing the advice of others on what they have found to work well on their printers; I'll detail my experiences below.
Heated aluminium build plate lined with masking tape:
Excellent adhesion, but some issues with under-extrusion: the warp in the bed brings the nozzle too close to the bed and the nozzle gets blocked.
Heated aluminium build plate with no liner:
Pretty much unusable. When I properly level the bed, the nozzle will hit the build plate when moving across the X-axis (the plate appears to be warped upwards along the centre of the Y-axis). Lots of extrusion problems due to the nozzle being too close to the warped part of the bed.
Heated aluminium plate with borosilicate glass build surface:
Very flat surface, so I get perfect bed leveling. But... the glass is 200x300mm and my alu plate is 220x275mm, and all of my prints lift. From what I gather this is due to the temperature differential: glass absorbs heat very well, so the lower layers are warmer and more pliable than the upper layers: et voila, printed items lift. I get the best results with this method so far (see these examples - sorry for the facebook links! https://i.imgur.com/Kqg0Rgb.jpg https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58B5CF99 https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58F481E8 https://scontent-lhr3-1.xx.fbcdn.net/v/ ... e=58B83843)
Un-heated aluminium build plate lined with masking tape:
Not tried.
Un-heated aluminium plate with borosilicate glass build surface:
Not tried.
Un-heated aluminium plate with borosilicate glass build surface lined with glue stick (or some other material):
Not tried.
I've also tried an inductive Z-probe so that I can use automatic mesh bed leveling. That's currently on hold because the sensor I bought appears to be knackered and the seller is being really fussy about refunds/returns (the sensor accepts 6v-12v; the output should be 0v when not triggered and the same as the supply voltage when triggered - my sensor reads 6v out (on a 12v supply) when not triggered and 4.7v when triggered). I can trigger the Z-min input when I hook it up to my bench power supply and feed in 5v, but the sensor itself appears to be knackered.
Based on everything I've learned so far, my best bet seems to be an inductive sensor and mesh bed leveling. That should allow me to use the bare aluminium heated bed and have the software compensate for the warp in the bed. While I shout at some useless seller about a replacement sensor (I'm not buying a new one, I begrudge paying out of my own pocket for a faulty item) there are still quite a few things I'd like to print. I'd be keen to hear any advice people might have on build surfaces.
FYI: I print PLA at 205°C with the bed set to 50°C (60°C first layer); I usually use a layer height of 0.2mm. I can post my Slic3r settings if needed.