V6 Troubleshooting
Common solutions to issues with your V6 HotEnd
The most common causes of trouble with extrusion on E3D hotends are as follows
Inadequate cooling and Filament Jamming
Inadequate cooling is the most common cause of problems, accounting for nearly half of all issues reported to us. Consistent performance of the extruder is heavily dependent on having a sharp temperature differential between the nozzle and where the cold filament enters. If the unit is not cooled properly, filament will melt too high in the unit and cause jamming.
The entirety of the heatsink must be kept cool at all times during printing. For this to happen enough airflow must be directed at the heatsink, and that airflow must be distributed over the whole heatsink. The use of the supplied 30mm fan and duct is highly recommended, the supplied fan has adequate airflow (4-5 CFM) and the duct is specifically designed to aim that airflow at the fins of the heatsink.
An easy way to check that your heatsink has sufficient air flow is to simply feel the heatsink with a finger after a print has been running for some time. (Be careful not to touch the heater-block, it will burn you instantly) The entirety of the heatsink should be cool to the touch, including the bottom fins closest to the hot parts.
Like the heatsink and fan cooling your CPU, proper thermal conduction is necessary for the heatsink to work. In the case of your E3D hot end, the threaded heat-break tube should be snugly tightened into the heatsink otherwise the threads will not make sufficient surface contact to conduct heat. If you are printing in hot climates or continue to have issues, a liberal coating of thermal paste on the upper heat-break threads will ensure much better thermal contact with the heatsink. Even with thermal paste the threads can vibrate loose and cause performance issues. To combat this heat up the heatsink with a heat gun and then thread in and tighten the heat break tube with two pairs of pliers. The heatsink should contract around the heatbreak when it cools and ensure a solid connection.
Common issues are:
- Not wiring the fan directly to a 12v or 24v power supply.
- Connecting the hotend fan to the “Fan” output on an electronics board, which is software controlled and should be used for print cooling, not for a hotend fan.
- Using a 3rd party designed printed duct that is improperly designed and impedes flow or does not direct flow properly to all fins. This is not to say all ducts other than the supplied one are bad, but that you should be cautious in your selection or design of a duct.
- Having some sort of obstruction in front of the fan or behind the duct which restricts airflow.
- Heat break tube is not snugly tightened into the heatsink.
Misconfigured Retraction
Choosing slicer settings is a bit of an art and everyone has their particular preferences as to how they print. The following guidance is to help people avoid common configuration pitfalls.
A common issue is massively excessive retraction distances. In direct configurations retraction of 0.5 to 2mm is all that should be needed for ooze-free prints. We use around 0.6mm for ABS that oozes very little, and 2mm for the very floppy flexible filaments that like to ooze a great deal and need a good tug to pull back the soft filament from the melt zone. For PLA we stick with retraction settings no higher than 0.8mm.
Bowden configurations are more tricky as the amount of retraction needed is dependent on factors such as the length of tubing and the stiffness of the filament has more impact on the needed retraction. A good starting place is around the 2mm mark, which you can increase if required.
Retractions of 5mm or more are troublesome as they pull hot filament up into the cold areas of the hotend where they can freeze, adhere and jam.
You should be able to print at both very high, and very low speeds with your E3D hotend, but you may need to adjust your temperatures. Very high speeds will require higher temperatures in order to melt the filament quickly enough as it passes through the hotend. Very slow prints do not require as high a temperature.
Nozzle Blockages
Debris, dust, scorched carbonised plastic, contaminants in your filament, all of these things can enter and accumulate in the hotend. Debris can then block or partially obstruct the very small hole in the tip of the nozzle. This can be as subtle as high extrusion force, or thin ribbon like extrudate, or it can simply be a complete blockage of the nozzle where no plastic can pass through at all.
There is a fantastic guide to unblocking nozzles present on the Bukobot website which shows a range of techniques and procedures. http://bukobot.com/nozzle-cleaning
Bad Filament
There are a huge number of filament vendors out there, to cater to all needs and budgets. The E3D hotends are designed to cope with and print the vast majority of filaments on the market.
Filament must be of an appropriate dimensional tolerance in order to smoothly pass through the hotend. Filament that is too big will have excessive friction in the hotend. Filament that is too thin will buckle or snake inside the hotend and jam. Be aware that just making a couple of measurements on the start of a spool will not reveal if the filament has bulges where the diameter of the filament is too wide, or hard kinks that will not easily pass down the hotend. Filament can also be out-of-round or oval in cross section, this can lead to deceptive measurements if you do not measure your filament at multiple angles.
1.75mm Filament:
Should be within 1.65mm to 1.85mm in diameter.
Significant increases in friction occur once diameter exceeds 1.90mm.
3mm Filament:
Usually 2.85mm nominal diameter, but the hotend should handle filament that is 3mm nominal as long as it is accurately 3mm.
Significant increases in friction occur once diameter exceeds 3.05mm.
Some particular brands/colours of filament are particularly troublesome despite having good dimensions. This may be due to additives added to bulk-out the filament and reduce costs, particularly in the cheaper filaments. The exact mechanism or cause of why this happens is not clear, but it seems that some of these filament are more “sticky” when partially molten and therefore cause more jams. Ultimately the solution is here is to stick to good quality filament.
Black is often a troublesome colour as unscrupulous manufacturers can easily hide low quality recycled regrind behind lots of black pigment.
You cannot use 1.75mm filament in a 3mm hotend. Please stop asking. If you think you might be able to use 3mm filament in a 1.75mm hotend you shouldn’t be modifying or building a 3D Printer. Put the screwdriver down.
Misconfigured thermistor/temperature
The supplied thermistor is a Semitec 104-GT2 and your firmware must be configured to use this thermistor.
For more information about how to update your firmware for your new thermistor, look through the V6 Firmware guides.
Using an incorrect thermistor can result in temperatures being too low and increasing extrusion force, as well as producing prints that are poorly bonded.
You may find that after changing your HotEnd you may need to use slightly different temperatures, as a guide at E3D we tend to print PLA between 190C and 210C, and ABS at 230C to 240C. Your particular filament may however need different settings.
PTFE tubing not properly inserted (where applicable)
In hotends that use PTFE tubing:
- E3D-v6 Bowden 1.75mm
- E3D-v6 Bowden 3mm
- E3D-v6 Direct 1.75mm
- E3D-Lite6
The PTFE must be inserted to the fullest extent possible, the HotEnd is designed to allow the tubing to pass right down into the heatsink, and in v6 1.75mm HotEnds the tubing passes right down into the HeatBreak.
On bowden systems it is especially helpful to 'lock in' the PTFE tubing so that it cannot move around during retraction, this increases reliability, and gives much better retraction performance in general. To do this, push the PTFE firmly into the HotEnd, while pulling upwards on the black collet that retains the tubing. This locks the tubing into place so that it cannot move during retraction. It is important to do this at both ends of the tube.
Without the tubing the filament has room to bend and slightly buckle inside the HotEnd, which prevents the extruder being able to exert adequate force through the filament as it acts like a spring when buckled.
The PTFE tubing is absolutely necessary in the E3D-v6 1.75mm Direct HotEnd. Some people on the internet say it is not needed. Those people are wrong.
Poor extruder design
We recommend the use of a geared extruder such as the Titan with a compact but powerful motor for use with the V6. Many stock ungeared extruders that come with 3d printers are not capable of providing enough torque to provide reliable extrusion. If you are still using a stock extruder and finding issues with under extrusion or constant jamming you may want to consider upgrading the extruder.
Still having trouble?
If you are still having trouble, we are here to help. Please contact us either via the website live chat or via support@e3d-online.com.
9 Comments
hi guys, what should the temp be on the outside of the heat block at 215c? should it be 215c / 419f or is there loss through the block. I’m troubleshooting a jamming heat break and my infrared temp gun is only showing 244f (on the outside of the block) when 215c or 419f is requested by the controller. Seems cold filament would definitely jam. This is after trying to load filament in a clean nozzle with no obstructions and getting jam on 3rd attempt.
Mike Hayes - Reply
You IR gun makes use of a measuring spot that is larger than the heat block. The laser point is NOT the measured heat spot, it marks only the center of it!
Thorsten R. -
Doing some experimentation and testing, I found out that listing just the CFM of the fan is absolutely not enough. This document recommends using the CFM of 4-5, but this might not be enough depending on another parameter, and that is static pressure. The fan supplied with the E3D v6 is actually 6.50 CFM according to the specs (https://dcfan.en.alibaba.com/product/604...). I tried to use a fan which was 5.47 CFM (https://www.tme.eu/en/details/ha40201v4/...) as it was within the specs that this document listed. I found that the lower fins were hot to the touch (at least 50 °C). Then I found out about static pressure. The fan supplied with E3D v6 is 4.82 mmH2O, while I was using 2.03 mmH2O. As you can see, this is absolutely not enough. I found that the supplied fan cools at least 4x better. It would be nice if this guide could be updated with the correct specs AND the static pressure.
Thorinair - Reply
my heat block is leaking out through the top, i took apart and re-tightened several times. the only thing i cant get clean is the heatblock. there is filament on the threading inside the heatblock and i cant get it out. Do i need to buy another heatblock or is there some way to remove this filament from the heat block effectively?
Suntorn Pogasic - Reply
E3D guys, could someone comment on the maximum ambient temperature surrounding the hot end? On the Prusa forums people are saying that having an enclosure air temp 35C or higher will cause PLA to clog, but I can’t find any E3D documentation to that effect. Given that many high end 3D printers are enclosed and manage to print PLA just fine, there’s nothing wrong with enclosing the printer, it would just be nice to know the operating assumptions.
Thanks!
Michael @ http://3dupfitters.com
Michael Czeiszperger - Reply
hello i have a stock cr10s my first upgrade. i ordered the 12v e3dv6. i am having an issue when i turn power on it starts to heating up by its self untell i turn the machine off.
Thank you in advance!!
Douglas w Paul Jr - Reply
I recently replaced my Prusa hotend with E3D Prusa MK3 MK3S V6 HotEnd Kit. Since installing I’m getting fluctuating temps and suspect the thermistor and/or its firmware.
Is there Prusa specific instructions somewhere since it seems to be a special version?
Jeff Storey - Reply
I bought a Titan aero for my cr-10s but it won’t allow me to upload the changes in firmware. I can easy upload a hex file but not a marlin file. Idk y. Is there a modded cr-10s hex file I can flash with instead of a marlin file? Everything is a stock cr-10s. So the only changes that are needed is for the Titan aero. Please help or send me a modded hex file please. My email is: peterlaucella@gmail.com
Peter Laucella - Reply
After 4 years of heavy use, my E3D V6 head started clogging frequently. Reading this blog, I did 2 things. First, I cut 1mm off the PTFE bowden tube to give it a new square sharp end. Then I disassembled the heater block from the head and did a good cleaning of the gap and cooling fins, which had accumulated some gunk. I also used electronic heat-conductive grease on the threads when reassembling. I had to heat the block (ABS preheat) for disassembly and reassembly, since there was trace stuff in the threads. The end result was successful, clogs ceased. The E3D V6 was a replacement head for a Deltaprintr Kickstarter kit.
Mark Gaponoff - Reply