A Quick Look at Cube3 Firmware v1.10 Purge function.

I had an opportunity to briefly try PURGE on two clogged ABS cartridges and one working PLA cartridge.

I was hoping for a miracle cure; but, unfortunately this wasn't it.  The PLA spit out a very long stream of filament that was long enough to make 3 or 4 coils on the print table.  Neither of the clogged ABS cartridges fared as well.  I think I know the reason why.

First, let's take a look at the print jet housing on each of the ABS cartridges.

Filament Guide Separation

Notice that the filament guide, which should be seated flush with the tip housing is pushed away by a substantial distance.  It was pushed from the inside of the print jet,  So, how does that happen?

Eric Albert sent me an image that gives us a clue.

Filament Block Taken From Print Jet Tip

As is apparent, this block of filament has not only taken on the shape of the print jet tip; but, seems to have moved out of the metal part of the print jet and backed up into the area of the plastic guide.  A part of the block of filament is beyond the range of the heating element of the Cube3's heating system.  It has solidified enough to block anything trying to get to the tip.  As the extrusion gear continued to feed material, something had to give  And, that something was the metal retaining ring that held the filament guide in place in the print jet housing.

In this case, the PURGE function is not going to have much chance of unclogging this particular tip since there is filament blocking the path that is not going to be heated.

My early conclusion is that we can probably predict the efficacy of PURGE by first taking a look at the filament guide as it enters the print jet housing.  I'd still try it; but, wouldn't hold much hope for a miracle cure.

On the other hand, if we catch a clog by being alert for that dreaded clicking sound, we may be able to avoid a total backup like we see above.  In these case, I think we are going to have very good results with purge.

I'll keep testing it.  I certainly have some good test cases.  An d, I'll let you know the results.  At least we now have a shot of recovering a mildly clogged cartridge.  And, that is a step forward.