magma hot end jams
September 22, 2013 08:28AM
Hello, yesterday i collected my first 3d printer (prusa i3) the steps the motor tuned and calibrated, the heating temperature is exactly as instructed. After printing the first layer - filament feeding stopped. I took apart ekstruder, pulled out the filament out and started printing at a lower speed again. After 5 minutes, he was jamed again. What could it be? Should cold filament pass the part on photo fully, (i mark the jam by red circle)? I want to take a 3mm drill and expand the hot end hole, but first I want to listen to advice. Thank you.

Re: magma hot end jams
September 22, 2013 09:06AM
Are you using PLA or ABS?

I have the same Magma hot end and some people have been able to print PLA but I have had no success. ABS works fine with lots of precautions.

You don't want to use metal tools inside it - the inside of the stainless steel tubing is supposed to be polished smooth.

You can find a thread here where there are some details (and complaints) about Magma but a few things to note:

1. Printing too slowly with Magma is more likely to jam.
2. Printing with PLA is going to be much more tricky than ABS
3. You want to set the reversal amount to be less than 1 (something like 0.8 or 0.4)
4. You want to make sure the teeth on the hobbed bolt are cleaned out every time it jams. I use compressed air for this.
5. It will jam if the Z axis is not adjusted properly and the nozzle is too close to the glass on the first layer.

The best way to clean out a jam like this is to unscrew everything. Sometimes it requires getting it hot and using leather gloves and/or pliers to handle while hot (the top aluminum part should remain cool enough to touch, the bottom part is hot). After unscrewing the brass nozzle you may be able to push the material through. Usually what happens is you are using PLA and it swells inside the stainless steel tube. I have gotten this unstuck by carefully inserting a very small Philips screwdriver and twirling it (by hand!) in the center of the filament (avoid touching the walls) to remove the jammed filament.

Once you have it disassembled you can soak everything in acetone in a closed jar overnight.

You can get air sprayer cleaning brushes which use nylon bristles on a small metal shaft - these are good for solvent cleaning. You want to avoid metal bristles. There are also small dental brushes available in pharmacies (for cleaning between the teeth) which are nylon on wire and work well also (but are not long enough usually).

You probably have some swollen filament in that part of the tube. Once you get it out everything should go freely. The stainless steel doesn't carry heat and has probably never gotten hot enough to melt anything. The aluminum heating block and brass nozzle may have gotten clogged (especially if you tried to print using PLA) and may need the solvent cleaning approach.

Search for magma clogged and I think you'll find quite a few threads addressing this both here and in Printing.
Re: magma hot end jams
September 22, 2013 10:10AM
What temp are you printing at?

Iv found with all metal hotends you need to run much hotter then normal

i run Faberdasher PLA at 230C

Cheapo pla around 250C

otherwise i get jams

iv also confirmed my temps with a temp probe pushed into the hotend.

try going hotter remeber theres nothing that can melt and your okay up to 300C (set max temp in firmware to 300)
Re: magma hot end jams
September 22, 2013 12:09PM
Thanks to all for advices. I do not know how, but not seen that magma head not support correctly pla. I use 230ะก for pla. And i tried up 250C - same result. This will be the right decision, if i order J-HEAD for PLA 3mm? As I understand it - J-HEAD has thicker hole.
Now i try to clean my magma hot end.
Re: magma hot end jams
September 24, 2013 11:38AM
i have a similar stainless steel hotend i tried many including everything papergeek says it did help but i would still get jams just less often.

what worked for me was sponge and oil on filiment. i used cooking oil and have not jammed since(about a week so far) i even let hotend sit at 170c for 3 minutes and still no jams. its an easy thing to try. it does not seem to effect prints at all. i even noticed i had so much oil at one point it left a puddle at cold end of tube so just a drop or two of oil in sponge goes a long way.

hope this helps
Re: magma hot end jams
September 24, 2013 12:57PM
Try pointing a fan at the barrel of the hotend. It helped me.
Re: magma hot end jams
September 24, 2013 07:17PM
what about other filaments ? did you try abs atleast or nylon ?
Sorry, only registered users may post in this forum.

Click here to login