Winston discovered an issue with the extruder steps per unit. The default Zeepro configuration of 290 appears to under extruding by a few mm per 100 mm. Three printers we have tried exhibited this behavior (Winston’s and two of mine) so it is probably common to all of them. The new version 18.104.22.168 makes this change default. Please be aware that the JPod Marlin as of 22.214.171.124 enables the EEPROM saving of these parameters, and subsequent restore. If you are running this version, you can simply use M92 E316 to adjust the extruder steps per unit to 316 to match the new default. This only sets it temporarily, however, and is good for testing your own printer to find the ideal setting. Once you get the right value, use M500 to save the setting to EEPROM so it will persist across a power cycle. This newer version 126.96.36.199 enables printing the EEPROM parameters, so you can use M503 to check your settings (Look for “echo: M92 X201.00 Y201.00 Z3200.00 E316.00” to confirm the change).
You could likely make a similar fix to stock firmware by adjusting the extrusion multiplier. I just like my extrusion multiplier baseline to be 1.0 for some reason.
Thanks Winston for forwarding this information!
Here’s a couple of pics with the tweak. The two gray cubes are printed with the old setting. I believe I tweaked the extrusion multiplier on the second one, but not enough. See the thin top layer filament and insufficient bridging. The white and yellow were printed with the tweak and now look water tight.