Compare notes on Prusa's prime tower

[3D Printing Tips and Tricks]

Printing a two color object both colors in PLA Silk which can be tricky depending on who made the stuff and how old it is...

I decided to use a priming tower to ensure an optimal finish this time because the silk was really old...

Anyways I noticed that when the nozzle started a layer and went first to the prime tower it Detracted... and when it Detracted it left a blob which eventually caused a crash that knocked the tower over. GRRRRR!!!

So... I fixed it in the following way...

The "Retract on Tool Disable" (in the Extruder 1 thru 5 settings in the Printers tab) was set to 1.2mm with 0 for "Extra Length on Restart". I typically set this retraction to much higher when I don't use a Prime tower to get the material out of the melt zone. However with a tower that should not be needed.

This setting would retract 1.2mm when the tool goes to park then Detract 1.2mm when it started a new layer at the Prime Tower. I set the Extra length to -1.2mm which in turn meant that there would be no Detraction. I.e., the material retracts 1.2mm and stays there and as the tool extrudes on to the priming tower it then primes up the tools pressure as it extrudes on to the tower (which is what it's for!).

Worked fine...

So... Note to self... When I use a Prime Tower I have to nix the Detraction at the start of the layer for each tool used.