# Specific 3D Printers, Scanners, & Hardware > RepRap Format Printer Forum > MakerFarm Forum >  Prusa i3v   ---  Filament Jamming and Slipping  ---  Replacement/Upgrade Extruder ?

## jtice

Ever since I have had my Prusa i3v 10" I have had alot of issues with the Filament slipping, and I am recently thinking that its due to the filament jamming in the extruder.
Since abbout 60% of the time, when I pull out the filament, it will have a bend/kink in it.

What tips do you guys have for preventing this?

and 

What is a good replacement / upgrade extruder setup?
The more open direct drive setups look like they would be easy to keep an eye on, and less to go wrong.

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## iDig3Dprinting

what extruder and hotend do you currently have?

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## jtice

I have the origial extruder setup, looks like this.

With this cooler setup installed.
https://www.thingiverse.com/thing:335613

And this fan duct.
https://www.thingiverse.com/thing:351280

Hotend is what came with the printer, Hexagonal 0.4mm

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## tonybuckley

Let me say first, I am a noob to 3D but an engineer.

But I have played a lot with this on my E3D-V6.

At first I had clicking from the extruder and this was because the tension bolts were too loose.   Maybe yours are too tight so the filament is being deformed?   The extruder should neither bend nor kink just serve.   It is kinking at extruder level, or in the hot end?

Only other thing I can think off is temp.   Is this bog standard PLA or ABS or one of the newer magic 'things'.   It would bend and jam if it cannot be extruded due to a low temp.    And do not believe your temp reading depending on your hotend thermistor; they can lie.   If you can independently measure, then do so.

Have you raised your Z axis and done a nice long extrusion while watching and listening?   Both watching and listening are brilliant tools to diagnose a problem.

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## printbus

A composite listing of what people have reported as causes for their extrusion stopping is available here - http://3dprintboard.com/showthread.php?13045-Extruding-Problems&p=58220&viewfull=1#post58220

The bend/kink is very insightful. You're using 1.75mm filament, right?  The greg's wade extruder parts provided by MakerFarm are, by default, optimized for 3mm filament since the same parts are used with 3mm hot ends and filaments.  This creates at least two problems for users of 1.75mm filament.  First, when the smaller filament is pushed against the hobbed bolt, the center of the filament is a bit offset from the center of the feed hole in the top of the hot end.  Second, the pass-through hole at the top of the Wade's block is oversized for the smaller 1.75 filament.  For some people, this combination has led to the filament bending or kinking in the short distance where the filament is unsupported between the hobbed bolt and the top of the wade block.  More flexible filaments are obviously more prone to do this. 

One easy option is to add a 2mm ID tube to that channel in the wade block, raising it up above the block as far as you can without getting in the way of the hobbed bolt or the idler pulley.  I used aluminum tubing from a hobby store, but I've heard a section of empty ink tube from a Bic pen works fine as well.  This tube eliminates the slop in the hole through the wade block and reduces the length of unsupported filament.  

FWIW, the thread above includes a link to my modified Greg's Wade parts on Thingiverse that give the user a lot of control over the extruder parts, including being able to optimize them for 1.75mm filament.

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## jtice

This is plain PLA filament. (though I have had it do it with ABS also)
I run PLA at 190. I have not played with the temps all that much, I have sliiiiight stringing, so I dont think I should raise the temp anymore.

Far as I can tell, it seems to kink/bend right above where the metal of the nozzle starts, basically right below the extruders hobbed bolt.

So, I think printbus, you might be onto something here, I will look into adding that section of tubing like you mentioned.

I used to have it slip, alot, but tightened up the tension bolts, now, I dont think it slips, until it has a jam.

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## printbus

A picture of the aluminum tube added to my original extruder are in this post of my build thread - http://3dprintboard.com/showthread.p...ll=1#post26647

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## jtice

Thanks alot, that solution really makes sense.
Now, I just hope I can find the right size tube !

But, if its kinking due to jamming, I still need to figure out the cause of the jam also.
Though, with your tube fix, I figure it can force the filament through stronger than it could without it.

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## tonybuckley

> This is plain PLA filament. (though I have had it do it with ABS also)
> I run PLA at 190. I have not played with the temps all that much, I have sliiiiight stringing, so I dont think I should raise the temp anymore.
> 
> Far as I can tell, it seems to kink/bend right above where the metal of the nozzle starts, basically right below the extruders hobbed bolt.
> 
> So, I think printbus, you might be onto something here, I will look into adding that section of tubing like you mentioned.
> 
> I used to have it slip, alot, but tightened up the tension bolts, now, I dont think it slips, until it has a jam.


I only use 1.75.   But as I use the E3D hotend I had to drill out the hole to allow the plastic sleeve to be inserted and it has been brilliant.

As always there are so many variables and your kit is different to mine so my opinion is pretty worthless.   Good luck with it; others have so much knowledge across multiple kit.

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## printbus

Yeah it could be a combination of things. Most issues on these printers are. 

Don't rule out borderline low temperature as part of what is going on.  FWIW, I print all of my PLA in the range of 210 to 225, depending on the PLA and the degree of finish gloss I want to achieve.  The uncalibrated settings don't readily port from user to user, but at 190 it could be you're marginal.  Printing too fast, or printing too fast for too long, or printing with too much print cooling airflow could be having an effect on how easy the filament can be pushed through the nozzle.  

Also note that newer hexagon hot ends ship with a silicone insulating boot that slips around the aluminum block.  Something like that might help maintain a desired temperature throughout the aluminum block, especially with cooling airflow passing over the block. Even with the e3dv6 hot end I'm using now, I box the aluminum block with a few layers of kapton to help serve as an insulator.

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## jtice

Been a while since I really read up on all this, so I might be mistaken...

But, I though that if the upper end of the hotend, where its fins are, got too hot, that it would cause the filament to melt a bit in it and start to stick, causing jams.
That is the main reason I have been afraid to go over 190
That is why I went ahead and installed that upgraded cooling system shortly after building it.

The other day was my worst jam ever, after if was printing for about an hour. I left it overnight.
Next morning, I heated up the nozzle, and when I went to pull the filament out, and it snapped off, down in the metal part a bit,
So I had to poke a guitar string up through the bottom to force the filament out.

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## tonybuckley

> Don't rule out borderline low temperature as part of what is going on.


I print PLA at 225 on my E3d.   My infrared temp sense says it is 180!   But of course that is an exterior temp.

As with all this stuff.  EXPERIMENT and do not believe the readings.  As I said watch and listen.   A simple long exttrusion from Z height is very revealing.   See how it flows straight, or if it coils.

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## jtice

> I print PLA at 225 on my E3d.   My infrared temp sense says it is 180!   But of course that is an exterior temp.
> 
> As with all this stuff.  EXPERIMENT and do not believe the readings.  As I said watch and listen.   A simple long exttrusion from Z height is very revealing.   See how it flows straight, or if it coils.


What is the coiling a sign of?
Mine will coil, like mad. Pretty much always has.
If I have recently cleaned out the tip with the guitar string, its a bit better, but generally, will never fall straight out of the extruder, it will coil and kinda ball up.

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## tonybuckley

> What is the coiling a sign of?


So what I was suggesting was raise the z axis a fair bit and then extrude via a tool such as pronterface.   That's my procedure for loading new filament and running it through to change colours for example.

In my opinion, you should see a nice line of filament coming through and stringing down to the base under gravity, very quickly cooling and setting from the hot end.

If it madly coils under those conditions, I would suspect it is far too hot so as it comes out, it is shocked and coils and clumps. 

I'd be very interested to see what the thermos report as your temp to achieve a nice clean line of filament?

I will say again.  I am a noob on this so take everything I say with a pinch of salt and my only experience is the e3d hotend which I chose after looking at the designs and been very pleased with.  I don't mind being shot down in flames (nicely) but this is the behaviour I would expect.

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## kd7eir

I've had much better luck since increasing my PLA temp to 225°. I have the same setup except that I am using 3mm filament.

The coiling is most definitely a sign of either a clog in the nozzle or something at the very tip of it. I once found a small piece of lint just touching my nozzle and causing the filament to coil. You can easily clean the tip of the nozzle of such stuff by CAREFULLY placing a small lid with some isopropyl alcohol in it right against the nozzle tip while it's heated to extrusion temperature.

I always raise my Z axis and extrude several millimeters of filament through the nozzle anytime that I change filaments.

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## tonybuckley

Don't know then.

But you could use it to your advantage :-)   http://www.bbc.co.uk/news/science-environment-35171408

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