e3d v6 help

I posted an issue a few days ago about random motor movements, and how I thought that was causing my extruder to jam. I replaced the SD card as someone suggested, and I didn't notice anymore random movements, but there is still a problem.

I am using an e3d v6 (not a clone), and it appears that melted plastic is oozing up into the cold end jamming the extruder.

When I first started the e3d, I printed a few parts that took a few hours, with no problems. I then went to print a five hour part, and it jammed at about 1 1/2 hours. That's when I started posting the questions (about the extruder motor randomly retracting several mm), and replaced the SD card.

I tried again, and it jammed after 10 minutes. The e3d online help said the cooling fan could be too week, so I ordered a new one. But that was when I told them it failed after an hour and a half and that it seemed a little bit slow.I don't think it's the fan because shouldn't it print fine for way more than 10 min even if there wasn't a fan installed?

I am at a complete loss as to what the problem could be.

Please help, thanks,
Scott

So I took it apart (a little bit),and tried it again. This time I watched it very carefully. The extruder never reversed directions, so that's not a problem anymore. At exactly 10 minutes into the print, it stopped extruding. I pulled the filament out, and here is what it looked like. and the entire measured end was soft and 'meltyish'.

The section that is 2mm in dia is in the area of the plastic tubing that goes into the top of the e3d v6. I am/was 99% sure that the tubing I used was the proper stuff (I got it on Ebay), but is it possible that it's the wrong material and that's causing the problem? Obviously the plastic is getting too soft way too high up into the cold end, I just don't know how.

If anyone has any ideas please help.
Thanks,
Scott

The cooling fan on the e3d is connected directly to 12v power and so runs at full speed all the time? And when running it's moving plenty of air (you should be able to feel the draft easily)? The bottom of the heatsink is clear of the heater block and the gap between the two is occupied by the narrow part of the heatbreak?

If you have a digital thermometer, measure the temperature of the bottom of the heatsink after the jam happens. The heatsink should be well below 60C, typically between 30 and 40 depending on hotend temperature and how much air the fan moves.

The fan does seem a little bit slow. I had this already from something else, so I only ordered the metal parts from e3d. I did order a new fan from e3d though just to try that and see if it helps. And yes, the fan runs all the time.

There is the gap between the hot end and cold end as you said. I will have to borrow a temp sensor from work to check the temp as you said to do. That is a good idea, and will do it Monday.

I am curious though, if anybody knows how long it should be able to print if there was no fan. It just seems like it would take a lot more than 10 min for the cold end to get too hot with a slow fan.

Thanks for the quick reply and suggestions. Like I said, I have to wait till Monday to get a thermometer, so I'll let you know then how it goes.

Thanks again,
Scott

Good to know changing SD card helped with previous issue. Can you post the temperature you are using, extrusion rate and printing speed? And most importantly what's your retraction settings?

Edited 1 time(s). Last edit at 06/05/2016 12:49AM by ggherbaz.

Are you using retraction? How much? If it's a direct extruder you should be able to use 1-1.5 mm retraction. If you're retracting 10 mm with a direct extruderyou're going to have a problem.

The E3D v6 comes with teflon tube to fit inside the heat sink. Is there any reason you aren't using that tubing? Did you lock the tubing in place with the bowden fitting?

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

To answer ggherbaz and the digital dentist:

I'm printing perimeters at 50mm/s, infill at 60mm/s
Printing with PLA at 185*C
Retraction is set to 1mm at 20mm/s

I only ordered the metal parts from e3d online, because I already had the tubing, fan, thermocouple, and heater. They did send the little plastic insert though to lock in the tube, and I am using that.

I think the fan is a cheap China made one. Someone on Thingiverse told me that he had a fan failure, and it will not print long after that. At the moment, I believe that the fan is failing, getting slower and slower. That would explain why it seems like the problem happens quicker.

Hopefully the fan will get here quicker than the v6 did.

I will post as soon as I get that in and try it out.
Oh, and to be honest, I'm not positive the SD card fixed anything. Since the unexpected X, Y, and extruder movements were very random, and I have really only watched it for about half an hour withe the new SD card, who's to say it would have acted up in that time frame anyways. Sometimes it would act up after a few minutes, and sometimes after an hour or more, I won't know if it's fixed until it never does it again. I'll just call it good if it prints the next couple of parts ok.

Thanks again,

Edited 1 time(s). Last edit at 06/05/2016 08:44AM by koenejet.

I'm a great E3D supporter - but the 30mm fans they supply are not great. But in all fairness to them, it's incredibly hard to find small fans that work well for long periods. I have fitted a shroud to my E3Dv6 that uses a 40mm fan, but even that one is starting to get a little noisy - it's not going to last a great deal longer. It's not E3D's fault - it's just that all of these little fans are made in China, and not made very well.

I'd gladly pay more for a quality fan, especially the one intended to cool the hot-end heatsink, but they don't seem to be available.

I bought one of these about 2 years ago and it has been holding up fine. It is thicker, heavier, and makes a bit of noise, but it is very well made, compared to the POS that came with the extruder:
[www.ebay.com]

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I also saw some on Amazon for rc car speed controller cooling. One is called a tornado from yea-racing. They are about $7-$8 each, and apparently very loud, but that may be the next one I try.

Actually, those I just mentioned are 5v motors, so you would have to drop the voltage a bit. So I'll probably go with the one the digital dentist suggested.

Getting reliable fans is definitely a problem. FWIW I bought 2 30mm from the following link that have been working well so far

[www.aliexpress.com]

Moving fans are quite sensitive to the orientation you mount them in. Ideally you want the movement in the plane of rotation.

I designed and built a 40mm fan shroud for my E3d V5 and its been working great. That 30mm fan was the loudest thing on the printer.

Yes, the 30s can be a bit loud. I had 40s at first, but the 30s are significantly smaller and lighter which is attractive when you have an overly heavy dual direct drive setup.

SUN ON fans are pretty reliable.

Quote
the_digital_dentist
I bought one of these about 2 years ago and it has been holding up fine. It is thicker, heavier, and makes a bit of noise, but it is very well made, compared to the POS that came with the extruder:
[www.ebay.com]

Well I got one of these and just tried it out. It printed perfectly for 1 hr 23 min. Then it jammed. I keep forgetting to get the digital thermometer from work, but when it failed, I pulled the fan off and felt the cold end. It was very warm to the touch. Not hot enough to burn, but very warm.

I'm still waiting for the fan from e3d online. Hopefully that one moves more air. Oh well. At least I'm moving in the right direction.

I do wonder though if I got a dud. The digital dentist said it works for him, and that it was noisy. The one I got is not noisy. I was surprised how quiet it was. It does move more air than the other One I had, but not as much as I expected.

Edited 2 time(s). Last edit at 06/08/2016 06:53PM by koenejet.

DC brushless fans are weird. I don't know if the lubricants need time to warm up or something, but it seems common for them to start slow and then gradually ramp up. They also seem to change speed quite dramatically over the first few 10s of hours of use. You might want to just leave it running for a while and see if it magically picks up some extra rpm. The other thing to check is that it is getting a solid 12V.

I did just think about the voltage earlier today. You would think that would have been the first thing I would have checked. Any way, I do have 11.97v to the fan. That should be close enough I would think.

It doesn't get much closer I keep thinking I'd like to get my 12V rail up to 13V or so. My fans are all on PWM mosfets so I can back them off to reach a noise/temperature compromise and the extra volt would be useful for the steppers and the heaters. Another thing on the todo list for the winter.

So I got the new fan from e3d online. I ran it on a 12v power supply for about five hours before I installed it.

It feels like it blows a bit more air than the other two fans I tried. But it jammed after a little over an hour. I pulled the fan off, and the cold end felt a little warmer than room temp. It was not as warm as it was with the other fans.

It just seems odd that it would jam like that for not being that warm. I never got a digital thermometer on it, but like I said, it didn't really feel that warm.

Any other ideas? Please help, I need to get this working.

Thanks again

Ok, if the heatsink is only barely warm we can take the fan out of the picture. Is it still the case that when it jams you have 20+mm of filament with an increased diameter? That's unexpected, and still leads us towards a heat problem. If it is still the case that the filament is expanding you could try adding heatsink compound between the threads of the throat and the heatsink to improve the rate at which heat is removed from the throat (but not on the threads between the throat and the heater block - we want that to be as poor a thermal connection as possible). Make sure the narrow part of the throat is exposed and in the clear between the heater block and the heatsink.

The other side of the coin is to make sure that the extruder is providing as much force as possible. When the hotend jams, does the extruder motor stall (make clicking noises as it jumps backwards between whole steps) or does it continue turning and strip a hole in the filament? Does the extruder motor run hot or cool?

What size nozzle are you using? Have you tried a spare, and/or a larger one?

I did assemble it it with heat sink compound between the threads and the heat sink. The heatbreak is visible.

When it jams, the motor keeps turning, slipping on the filiment. Sometimes I can manually push the filiment through, but it's very difficult to do so. However this last time, it is so stuck, I cannot pull it out or push it through. It's loose. I can move it up and down a little, but cannot pull it out or push it through.

I am using a .4mm nozzle that came on the v6. I only have 4mm nozzles.

Thanks,

Heh, just realised I've been repeating myself. Oh well, at least I'm consistent. You could try increasing the tension on the ilder in the extruder to avoid stripping the filament, which should allow more extrusion force. I'm out of ideas for why the filament seems to be getting soft so high up in the coldend though - that seems very strange. 0.4mm nozzles are relatively easy on the extruder, I'd have been more worried if you said you were using something wild like 0.2mm. It might still be worth checking for a blockage in the nozzle, but you've probably already done that.

I just took it apart to remove the jammed piece. I did tighten the idler, and I'm trying the print again. Will let you know how it turns out.

i did notice though, that on the piece of filiment I removed, there was a thin wide ring around it. This could have been from a small gap between the bottom of the plastic tube and where it is supposed to sit inside of the cold end?. But that is pretty high up into the cold end though. Any way, I made sure the tube was fully seated this time.

Thanks again,

Also, I find it odd that everywhere I read, people complain about the 30mm fans being really loud. Well the three that I have tried so far, are not. Even the one I got from e3d online. I'm not complaining that they are not noisy, but it makes me wonder if my three fans are not putting out enough.

The cold end isn't that warm, as I said previously, so it's probably not an issue. Just odd.

Ok, I may have found the problem. On the toranado extruder, there is a printed part that holds one of the drive shaft bearings. This part is real close to the motor. The heat from the motor was softening that part, allowing the bearing to move a bit, which takes the tension off of the filiment.

I wrapped that printed part with carbon tow and epoxy, wedged a Teflon shim between the part and the motor. There is now good tension on the drive roller, and hopefully it's all fixed.

I just started the print again, will let you know how it goes.

Quote
koenejet
i did notice though, that on the piece of filiment I removed, there was a thin wide ring around it. This could have been from a small gap between the bottom of the plastic tube and where it is supposed to sit inside of the cold end?

Yes, that could cause problems - good observation. Sometimes you have to chamfer the end of the ptfe tube to match the bottom of the bore and close the gap. Usually it needs to match the 118 degree angle of a standard drill to fit perfectly, but even a rough approximation with a sharp knife and sandpaper will help. But, you're right, that joint is deliberately high up in the cold end in the V6, and the filament should never be soft enough to expand into the gap up there. The mystery continues. I have some clone heatbreaks where the ptfe goes to just above the narrow part of the heat break, which is the worst possible place to have a joint. They suffer from the problem you describe unless I get the ptfe really well seated.

Getting all three fans bad from different sources would be a pretty bad stroke of luck, but I guess it's possible. There's something not right, but I'm missing it at the moment. I'm not sure how we could quantify the expected fan output. I have a strip of paper that I use both for feeling for the Z0 gap and for checking my fans are running as expected. It's about 3/4" wide by 10" long. If I hold it at one end and let the free end sit in front of the fan output from the heatsink, it deflects two to three inches in the draft. That's probably a completely unreproducible test, but it might give you some idea of what to expect?

I haven't run pla through my extruders for a while (which are homemade e3d v6 look alikes), next time I do I'll try and remember to check to see how far the filament softens. With abs it seems to barely get 2mm into the heatsink.

edit: cross posted with your last update. Sounds good - finger's crossed!

Edited 1 time(s). Last edit at 06/12/2016 05:12PM by JamesK.

So, almost two hours into the print, and it jammed again. This time the cold end felt almost as hot as the bed. About 55 degrees give or take. Much warmer than when it failed at one hour.

It also looked like my fix on the plastic bearing holder wasn't good enough. The bearing did move a little bit. Not as much as it did before. It looked like it was just at the point to where the drive gear would start to slip.

So it seems as though I have two issues. I think the biggest issue is the bearing block. Because if that isn't solid, the tension on the filiment keeps getting looser. I may just machine one out of aluminum.

Once that is correct, I'll try another print, and then focus on the fan if it's still jamming.

I'm still open to any other ideas though.

Thanks again,

If the heatsink is getting to 55 degrees, then it is likely to be the root cause of the jams. At about that temperature, PLA starts to soften and swell, Pushing soft PLA into the heat break will just make it swell more.

I didn't see it mentioned, so just to check.... You do have a shroud around the fan and heatsink, right? And the shroud is clipped to the bottom of the heatsink fins? Maybe you could post a photo of your hotend?

One point... when assembling the hot-end, it is important to do it correctly:
1. Heat the heater block to 200+
2. Screw the nozzle all the way into the heater block, then back it out about 1/2 a turn.
3. Screw the heat break all the way into the heatsink
4. Screw heat-break finger-tight into the heater block (hold using the heatsink for convenience)
5. Screw the nozzle hard into the heater block.

This way, the nozzle is as far as possible into the heater, for maximum conduction. The heat break is as little as possible into the heater, for minimal conduction. The heat break is as far as possible into the heat sink for maximum conduction. The nozzle is hard against the bottom of the heat break, to stop filament oozing out sideways.

FWIW, my experiences with "E3DV6" (actually Chinese clone) hotends... After months of trying, I never did figure out how to print PLA with an all-metal hot-end. I have good success with the hotends which have PTFE tubing inside. Retraction is especially a problem... don't retract more than 2mm for a direct drive extruder, and less is better. In fact, if I was trying to debug the hotend, I'd turn off retraction completely and live with a bit of stringing until all the rest was reliable. I thought that the puny little fan that came with it would be too small, but it works just fine. I had a 40mm fan on one, and it's no better than the 30mm. I expect a blower (radial) fan would be better than the normal axial fans, but never actually used one. The axial fans work just as well sucking hot air away from the heatsink as blowing cold air onto it.

I did assemble the v6 as mentioned. Retraction is set to 1. And the fan is on the blue plastic shroud that clips onto the cold end fins. And it does have the plastic tubing inside.

It's mounted in the Toronto geared extruder I printed from Thingiverse, so the entire v6 is covered by the print fan shroud. I have the fan blowing cool ambient air onto the cold end. I was afraid if I had the fan pulling the hot air away from the cold end, then it would suck warm air off of the heated build plate, and would not be as efficient. Make sense?

I'm in the process of making an aluminum bearing block to replace the plastic one. That should keep the filiment tension constant. After that, if it still jams (which it probably will) then I guess I'll try another fan. I saw one online called a tornado that gets great reviews. Apperantly it moves a ton of air and is really loud. It runs on 5v though, so I'll need to drop the voltage a bit.

And if none of that works, maybe I'll just buy the new assembled geared extruder from e3d online. That one came out just after I finished the toranado. Which is just my luck. I would have bought that if it came out before I started the toranado.

Edited 1 time(s). Last edit at 06/12/2016 08:22PM by koenejet.