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Hiya,

I’m new to 3D printing and also to forums but I really need some advice and guidance about my Makerbot Replicator Mini.

It’s constantly saying “Filament Jam” it starts printing and does a couple of seconds and then it stops.

I have been reading online and I have been lubing my filament with some oil (only a tiny bit) as the filament is PLA and I’ve read that it’s not already lubricated for printing? (If this is wrong then i have other spools I can use)

I have opened up my Smart Extruder, there was a slight build up of filament which i removed and put back together.

I have heated the extruder up, removed the nozzle and then ran filament through without the nozzle on and it seemed to come out fine.

When it does come out of the extruder with the nozzle on it’s quite a thin strand.

The nozzle itself looks bunged up so I have been soaking it in acetone and I think I may retry a print later with it back on.

The only thing I have managed to print was the Makerbolt set, so like 30 mins printing. I did have to keep unloading, lubing then loading the filament through the print though.

It isn’t making any clicking noises. I have the temp set at 215 degrees.

I have also read that the filament guide tube could be a problem too so I don’t know whether to remove it and try one without the guide.

I have a batch of new nozzles being delivered tomorrow, I’m hoping that they will make a difference. Does anyone have any advice about build up of filament around the nozzle?

Apologies for the long list of issues but I am really hoping that someone has some answers! :slight_smile:

Thank you,

Becky

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Hi Becky,

Filament jam detection is based on the difference between how much the feeding shaft is turned by the motor and how much filament feeding encoder has turned. There are a lot of things that can trigger this event like a weak motor in the printing head, the extruder shaft is not turning well and resists for many reasons like a bad nozzle or filament, filament is hard to pull by the extruder, the load spring is weak and does not push the filament against the feeding shaft hard enough, feeding tube is moving and pulling the filament out of the extruder, head moves so fast for changing position and filament roll is not turning freely so the filament is being pulled out, over-extrusion by wrong filament diameter value in settings, different filament materials with higher temperatures. At 215c good quality PLA should run out of the nozzle by itself when the extruder is not running. Some filaments have too much additives and particles that clog the nozzle frequently.

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Hi Becky,

A friend and I ran into this problem this week, trying to use some PLA filament from different brand than makerbot, on the replicator mini. What is triggering the “filament jam” is the encoder wheel. If you google “smart extruder makerbot” you will see how it is inside. Makerbot filament is slightly bigger than 1.75. Mine was thinner (1.74). Therefore the encoder wheel (which is fixed, and not spring held) doesn’t grip well against the filament anymore. When you print, if the encoder wheel stops spinning, it triggers the “filament jam” error. My friend had some tiny rubber-bands that he saves from when he buys vegetables. By opening carefully the smart extruder, we were able to fit this rubber-band around the encoder wheel, in the groove where the filament is supposed to rest against. This give additional grip to the encoder wheel, while being able to accommodate several thicknesses of PLA filament as rubber band is expandable.

It now works like a charm.

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Also i suggest to look on reddit/makerbot I found answers there for other problems related to this printer.