Instructions

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www.cel-robox.com
7.0 Calibration and Maintenance
Printing - My print is stuck to the
bed. Help!
Sometimes, depending on the print material
you are using, your print can be stuck to
the bed very securely, making it diicult to
remove. The first step is to ensure your part
and bed have cooled down fully; because
dierent polymers have dierent shrink rates
when cooling, the part will usually cool at a
dierent rate to the PEI sheet, causing them
to detach themselves. Because the bed is
removable, this should be simple to resolve
by removing the PEI sheet - see section 4.5.
Once you have removed the sheet, lightly
flex it and you should find your print snaps
right o.
Printing - Object begins to warp
and peel away from the bed during
printing.
The warp of printed parts is influenced by
the ‘coeicient of thermal expansion’ of
the material. This parameter describes the
degree to which a polymer changes size as
a function of temperature. The higher this
parameter, the more a part will shrink as it
cools. Because 3D printed parts are hot at
the base (due to the heated bed) and at the
top (due to the molten material which was
deposited last), but cooler in between, the
middle of the part can start to shrink at a
higher rate. This causes the bottom of the
part to warp upwards, and the top to warp
downwards. By maintaining the ambient
temperature, Robox® attempts to prevent
the part shrinking, by allowing the whole
object to cool evenly at the end of the print.
Therefore when printing materials with a
high shrink rate, it is essential that the door
remains closed during printing. Using brim
can also help with warp at the bottom of the
part by increasing the contact surface area
with the PEI sheet.