Once a new hot end leaks is it just throw away and get another?

Well I have successfully updated the firmware and calibrated my mendel (botmill) after two nights of reassembling the "pre assembled" glide :-(

Anyway all seems OK so I decide to trun on the heat for a test. I get a few little rat dropping then nothing... extrude a little more a few more rat droppings. the head must be hot enough as they drip from the tip. eventully I get it to extrude about 2 inches then nada until... a massive blob comes out from under the kapton tape. Urg.
Does anyone sell a nice complete hot end that comes with evrything you need and just works?. The extruder is a Wades.
So it looks like the best I will get to do with the printer on my holidays is simulate 3D printing haha,

I have no idea how to actaully remove the hot end.. I am trying to find good articles hoping I can salvage something..

Bill D

I had this happen with my mendel-parts v6 hotend , you have to heat it up to melt the plastic , then unscrew it. i just scraped the plastic out of the threads with a razor blade , but you can either burn it out or soak it in acetone to dissolve the plastic(will take a long time).

anyway i put it back together but this time with plumbers tape and i tightened it very tight, no leaks and ive extruded 3 feet plus of pla.

OK after the second failed attempt at extruding. I found the problem. Even though the second time around I had straightened the thing out and reinforced the join where the brass tube attaches to the PTFE with I high tem resistant putty. It should at least allow me to do a test extrude.
Heated it up to PLA tem, managed to clear the nozzle and then extrude a few inches befor it jamed and burst again.
This newbie could not work out what was going wrong. So I "Dismantled" the hot end and I find the Bore in the PTFE is 3mm not 1.75 even though it said use 1.75 and and 1.75 in it. Surely this will allow heat from the hot end to travel up the tube and clag things up?

Bill D

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'Serenity' Observatory

[www.billd.net]

"Money frees you from doing things you dislike. Since I dislike doing nearly everything, money is handy."

Groucho Marx

Yes the bore should be about 2mm all the way up.

Once PTFE has let go it done for in my experience. The thread expands and never grips tight enough again. Unsupported PTFE always fails like sooner or later.

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[www.hydraraptor.blogspot.com]

hey guys, i'm new on these forums.. i also purchased from botmill recently, but i got the axis 2.1 and assembled it myself. there's no support from botmill whatsoever even though i emailed time and again.

i would think that the axis 2.1 is just the glider but unassembled... but the 1lb of PLA they sent me is 3mm instead of 1.75. and it did fit down the PTFE very well. after many tries of reassembling the hotend, extruder and x-carriage, i've gotten the thing to extrude continuously.

a quick question for technobill... does the gears on your extruder face the front of the machine or the side of the machine? is the PEEK block mounted?

On mine, the the gears face the side.
If you have the option of making them face front its better I think. On mine as the Z axis goes up you get a narrower print area because the stepper or gears can hit the Triangle frame as it narrows.

PEEK Block? I wish. This was brass glued directly onto the PTFE no support whatsoever.

Amazing, if they had of shipped mine with the 3mm filament instead of 1.75 I probably would have been extruding and calibrating while on my holidays instead of having to wait a week for a replacement hotend and extruder to arrive from a third party.
Not even gonna bother chasing up BotchMill as earlier enquiries were not answered.

Bill D

I'm sorry to see that people are still trusting and having problems with Botmill. I bought a kit from them over a year ago that was literally useless. I won't go into my own trials and tribulations, but I ended up buying a set of plastic parts from nophead and recycled the nuts and bolts from the Botmill kit; pretty much everything else went into my pile of regrets.

From your description of the hot end you have, my advice is to just set it aside and buy either a Makergear kit (wonderful quality and technical support) or get the J-head from hotends.com. I've been using Makergear hot ends and have been very happy with them, but since I have seen so many people praise the J-head I figured I would order a few for my next few printers. The first one arrived today, and it appears like one that will last for a very long time and will be easy to service when I mess up and cook some plastic inside it.