Extruder Jamming

Hi

I am having a very frustrating problem. I am using a Gregs/Wades Extruder and it was working just fine for a while. But now after printing about 1 layer of my model the extruder jams every time. I open it up and I have a mess of bent filament beneath my hobbed bolt. I clean it out and restart. It prints about 1-2 layers then it jams again. I have tried both with abs and pla .. they both jam.

I am using pronterface and marlin.

hot end temp set at 230 for ABS and 185 for PLA.

Has anyone else had this sort of issue ? Would I be better off to try another type of extruder ?

What type of hotend? Could be alot of things. I would look at z height at start, are you too close, and not extruding very well. Is your hotend partially clogged?

Ive tried 2 different hot ends, right now im using a j head, and both give the same result. When I test extrude in the air everything works beautifully.

At what speed do you do a "free air" extrusion? You should be able to do it at 300 mm/min at least. Try a 30mm "extrude" first, wait a few secs then extrude say 40mm. It should be able to deliver a consistent continuous thread without breaks in it. If it doesn't, its an extruder/ hotend problem, If its ok, then we need to look at other possibilities.

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Waitaki 3D Printer

I don't get total jams, but I do have the extruder battling if I have the head too close to the bed.

I figured out the problem. I had upgraded my heated bed and due to the increased thermal environment my peek tubing was now getting too warm. I solved the problem by adding a cooling fan that now blows on the peek.

I am having this problem also. What command/speed are you using to set your fan?

Quote
drastic00
I am having this problem also. What command/speed are you using to set your fan?

I have no idea why anybody would want to put the hot end fan through the software and electronics just connected to 12 V anywhere you can connect directly from the power supply where power goes into your board anywhere. There has been a couple posts in now about that it's ridiculous you want to run it all the time and preferably even after the print shuts off to keep the plastic parts of your extruder cool

Edited 1 time(s). Last edit at 05/15/2014 04:11PM by cnc dick.

I am asking what speed he is running the fan. Half speed? Full speed all the time? What is giving good results? I am just getting started in this. I would imagine there are some applications in which you would not want the fan running all the time, but I do not know. I have not seen the posts you mention.

In less you have some extremely poor hot end you want this fan running full speed constantly all the time No matter what material no matter what. The plastic part your printing cooling fan you want control will say printing ABS would be totally off with PLA probably the first layers off and then come on gets to a small area like and antenna or some small diameter would be on full

Edited 2 time(s). Last edit at 05/15/2014 07:07PM by cnc dick.