hi, i had a clog driving me crazy and i ende dup pulling what looked like white tube from inside the hot end / nozzle? PTFE Lined Stainless Steel Thermal Barrier Tube Hotend – 1.75mm – 3D Printer MK7 Is this what i would need to buy to replace? are there any videos or guides on how to change thanks!
Yes, that happened to mine as well. You need to replace it. Make sure to meatier it because there are 2 online. One with thicker walls and one with thinner wall. I think it’s 4mmx2mm and 3mmx2mm. You need the 3mm one. Also, I suggest some baby oil on the filament, it helps to keep it unclogged and running smooth. Use some sort of cloth to transfer the baby oil. One little bottle will last about 2 years. That gives you an idea of how little you need to use
Yup - this is the nasty truth of Flashforge and ctc makerbot clone machines. Even if you run at cooler temps in time you will need to replace these tubes. Its a drag for sure.
This is true in part, so long as you use good quality PTFE tubing, your looking at 260C for maximum operating temp. So long as you never reach that or close, it should last but should be considered a consumable.
I’ve actually replaced my PTFE lined brass nozzle with a solid metal nozzle so I’ve got PTFE JUST in the barrier tube which operates much cooler anyway.
That’s the PTFE tube, 3mm OD 2mm ID that serves to prevent excess heat transfer too the filament that is in the barrier tube, stops it from melting too early into the nozzle.
Looks like that you might have been running your hot end too hot and it’s melted the PTFE tubing. PTFE has a melting point around 260C, depending on the grade.
You don’t want to buy the stainless steel barrier tube, mainly because it’s the wrong size/length. All you need really is the PTFE tube itself which is a nightmare to buy in the UK.
I managed to get myself some imported a while ago and it’s been fine for me ever since. I can’t remember the exact length but I think the ones used in the CTC extruders are 33mm long but I trimmed mine to 34mm so that there was a little bit of compression to stop the filament squeezing past the tube from the nozzle and jamming itself.
I got rid of those tubes, but tried running it and kept getting clogs. I made the upgrade to better extruders, with metal & spring loaded filament guides, I haven’t had a clog since!
Hey, I’m also waiting for an order on PTFE tube from Ebay, just to have around as spare. I’ll only know for sure if it’s the right size once it arrives which should be still this week, but for reference, this one is the one I ordered:
PTFE Teflon 2 x 3mm
The inner diameter is 2mm (to handle the 1.75mm filament) and the outer diameter is 3mm, in order to fit the nozzle (I hope). Previously I got another PTFE tube which was for 1.75mm filament and it didn’t fit - inner diameter 2mm / outer diameter 4mm.
You can’t run without the PTFE tube. It acts as a guide down into the nozzle. If you run without it, the filament will just flex in the heat break, twist and jam.
The only way to get rid of it completely is to replace the heat break with to a version with a 2mm hole down the centre and nozzle with a 2mm hole and make sure when you assemble that you tighten the heat break and the nozzle very tightly against each other to stop molten filament from spilling out between them.
This happened on my E3D Clone and it was a sod to clean all the cold filament from the hot end.
Agreed, the entire extruder is built differently than the cheap plastic ones that are stock with CTC. The upgrade was about $190, and there was some retro fitting, but I have a reprap style of feeder now, no more tubing. Hasn’t clogged yet, and that’s with 350+ hrs on mine!
To be fair, the default extruder with a fixed bearing and no pre-load is terrible. I bought a moulded abs spring loaded replacement pair of extruder on ebay, best upgrade so far. I plan on getting some stainless bar and making my own barrier tubes on my lathe so that I have an all metal hot end.
The shape of the new nozzles isn’t exactly the same as the originally installed ones - the new ones seem narrower/slightly longer - but the specs seem to match.
I will do some maintenance on the printer later this week and try out the new nozzles+PTFE tube and post the results here as well.
If you have an address send me over a message on here and I’ll post you replacment ones free cut to size all you need to do is remove the nozzle and slide this tube in and out the nozzle back on
Is it possible to purchase some of this tube of you as I have 3 printers down at the moment and am waiting for some from china which seems to be taking forever or do you know of a supplier in the UK?