Answered Wow! what a difference "SEASONING" makes!

Ive been printing fine since christmas when I got the robo... Recently Ive been having consistent jamming problems with 3 types of filament, all which worked fine before. Im thinking of pulling off the extruder and looking for problems. Anyone have any tips on what to look for? I have not changed temps, still using the default temps. When I pull out the filament, it usually has some teeth marks on it from the hobbed bolt.... not extremely deep, but easy to see and feel. Could I have it too tight? too loose? could the chamber not be getting cooled enough?

 

to add to this, it prints the first few layers fine, then the jamming typically starts after layer 4 or 5....

 

I pulled out the extruder, first off, there was tons of stuff gummed up around the thin part of the extruder (between the heat sync and the black square tip. Maybe this would hinder proper cooling of the fan. will look for a post about seasoning the nozzel. not sure how to go about that.

 

will try it now and report back.

 

Then add an oiler. It's a must have for trouble free PLA printing.

 

Just making sure. Your parts fan is running right?

 

both fans running well. I took the whole contraption apart today, loading tube off the hot end etc.... (Pain in the ass BTW) but made sure all was working ok.. Heated the hot end, cleaned off all the gunk on it and then put it back together... Added some oil drops through the chamber and then also oiled some filament and pushed it through as you suggested (all vegetable oil) now just going to do a few test prints with Simplify3d and see how it goes. We all have problems from time to time, and this forum is really helpful... just a tip for newbies, you cannot be afraid to take things apart on 3d printers, they are not yet at the point of maintenance free out of the box solutions....

On that note, I have never heard about seasoning the tip! thats a new one for me! Can anyone give some info on how/why this works, and how often it should be done?

 

printing the filament oiler... will add that. But is it necessary, or just the occasional seasoning?? At the beginning of each print couldnt I just add a couple drops of oil on the filament near the entry to the hot end?

 

Think of it the same way you season a cast iron skillet or coat a non-stick pot with oil before cooking something.

If we imagine that PLA is the same as sugar (which it's actually very similar) as you cook the sugar, any part exposed to hot metal will start to crystallize and harden.

When you coat it in oil, the oil actually polymerizes and creates a super slick coating that prevents the sugar from having points to stick to and crystallize.

The same is basically true in the nozzle. You coat the brass with a layer of super slick polymer. As the material begins to melt the oil prevents it from contacting the scalding metal and causing crystallization. These crystals can break off and cause a jam otherwise.

Occasional seasoning is pretty effective, though it's hard to say exactly how long the seasoning will last. Since PLA is pretty rough it will break off these polymerized oils from the surface and created crystallization points. Around 100 hours of printing or so is a decent approximation.

 

Well I put some veggy oil in a bottle with a small tip (used for applying MEK based ABS glue)

I will try to remember to add a small drop to the filament each time I start.... or use the filament oiler.... anyway, will try the large print I was doing and mark this thread as solved if it works....

 

If you add too much oil you can have bed adhesion problems. You only want the very slightest amount of oil applied to the filament, that's why am oiler is good as you can start with a drop or 2 and monitor it then add another drop if/when necessary.

 

I've also has the oil leaking out through cracks or above the heatbreak. Though never noticed a print issue from it.

 

well the oil seemed to have solved my issue, print that failed 4 times is now almost done... marking as resolved... Out of curiosity, is this a PLA specific issue, or will it affect other filaments as well?

 

Pla mostly but it can be beneficial for some other filaments

 

well seasoning and oiler seemed to solve the issue.... You guys rock!!!!