E3D V4 All metal hotend

[626Pilot]

The through hole in the heater block is for the Honeywell axial thermistor like what the buda uses. It's not recommended by E3d because they think it will give an inn accurate temp because of its placement, right next to the heater block.

That thermistor went out on my Budaschnozzle (started intermittently reading zero) so I ordered a couple replacements from Mouser. The first replacement failed. The second one lasted for a couple weeks until I got my E3D.

Long story short, the Buda thermistor SUCKS.

[Nylocke]

I never had any troubles with mine, even when I put it back together incorrectly and PLA flooded its way throughout the heater block (still haven't cleaned it...) dunno whats goin on with yours mate!

[mhackney]

An E3D question:

I had a "situation" today where I printed with black PLA. I then changed filament to pink. The way I do my filament changes is this:

With the hot end at temp, I retract 20mm. Then I pull the filament out from the EZStruder end. Insert my new filament and push it manually up to the hot end, forcing the remaining old PLA out the nozzle until I see the new color come out and I keep pushing about another 50mm or more. Then I extrude another 50mm from Repetier Host. With the SeeMeCNC hot end, I never have any problems changing this way. Today, after printing black and switching to pink, I had fairly large globs of black come out and contaminate the pink part. These didn't look to be extruded through the nozzle, in fact they looked like blobs and sat above the print surface. This happened 3 times during the print. I then switched to red PLA, did the normal procedure. I'm printing now and have had two sizable blobs of black again! (no indication of pink). Here's a photo:

[img]http://mhackney.zenfolio.com/img/s10/v1 ... 6629-3.jpg[/img]

You can see other black specks in lower layers. This seems like a lot of excess black filament that was collected somewhere but it doesn't seem to have come through the nozzle given how it sits above the surface (by 1mm or more). I've tried to watch the print to see if i can figure it out but to no avail. Anyone see this?

[626Pilot]

You may have some gap inside the hot end that allows the plastic to hide until the other plastic drags it out. Cleaning and reassembling the hot end, following the E3D instructions to the letter, might help.

When I change filament, I just remove the Bowden tube and pull the hot plastic out with it. This leaves a small melty blob at the end, which I cut off at a 45 degree angle. The angle makes it easier to feed in the next time.

To put in the new filament, I extrude it all the way out of the tube (so the hobbed bolt can deform it to match the calibration) plus another 40mm or so. I feed that in and seat the Bowden tube. If the filament hasn't completely changed color at this point, I feed in some more 10mm at a time until it's finished.

[mhackney]

I didn't RTFM for the E3D so I will do that!

[626Pilot]

I didn't RTFM for the E3D so I will do that!

While you're at it, make sure you don't make the same mistake I did. I thought to wrap PTFE tape around the threads as I had for other hot ends, but this will screw up the thermal characteristics. It runs better metal on metal.

[mhackney]

I've taken my hot end off and sure enough, there are leaks. Not 100% sure but it looks like PLA is leaking out the top of the aluminum heat block where the SS heat break installs. I followed the instructions when I set this up and made sure that the brass nozzle is not screwed against the heater block - there is supposed to be a small gap. Maybe I didn't tighten it against the end of the heat break and molten PLA was able to leak past?

[mhackney]

There is definitely PLA in the threads of the brass nozzle too. I was able to peel a string of it out of the threads. I suspect I didn't have it tight enough, I didn't use tools, only hand tight as I'd read that the heat break is a little delicate and I didn't want to over torque and break it.

[dpmacri]

There is definitely PLA in the threads of the brass nozzle too. I was able to peel a string of it out of the threads. I suspect I didn't have it tight enough, I didn't use tools, only hand tight as I'd read that the heat break is a little delicate and I didn't want to over torque and break it.

Did you do the part where you heated the hot-end up to 300C and then tightened the nozzle? I'm suspecting 'no' since you didn't mention seriously burning your fingers

[mhackney]

No! I didn't see that in the PDF.

[mhackney]

Ah, you mean Step 14 where it says:

Final step - DO NOT SKIP THIS STEP – using your electronics/software heat the now complete hotend up to 300C, then once up to temperature you need to do a final tightening of the nozzle against the heatbreak to form a good seal that prevents any plastic leaking. Use an adjustable spanner on the heater-block and another spanner or pliers to tighten the nozzle up.
The amount of torque needed is very low, using a spanner you can apply all the need- ed torque with a single finger.


NOW I've read it!

[626Pilot]

It would be nice if they redid that PDF. The layout is weird.

[mhackney]

Agreed, I didn't realize there was a 3rd page - where Step 14 is. Of course, I am old a senile too. And I didn't realize there was a 3rd page.

[626Pilot]

Agreed, I didn't realize there was a 3rd page - where Step 14 is. Of course, I am old a senile too. And I didn't realize there was a 3rd page.

I'm young and senile, so I understand.

[mhackney]

Ok, so I've cleaned out all the PLA - PIA! checked everything and I am certain my lack of RTFM resulted in improper assembly! I have now followed the instructions and heated the hot end up to 300°C (!!!) and tightened the nozzle against the heat break. I have a small space between the base of the nozzle and the heating block as instructed. Got everything back together and I am now printing again. I should be good.

I'm loving that pointy little nipple on the nozzle! Nice and clean.

[MSURunner]

I'm loving that pointy little nipple on the nozzle! Nice and clean.

Yeah, I'm a big fan as well. Provides enough brass to have captive heat but moves most of that heated mass a couple of mm above the part. Speaking of nozzles, what's the situation on that custom nozzle order that was floating around?

[Eaglezsoar]

Ok, so I've cleaned out all the PLA - PIA! checked everything and I am certain my lack of RTFM resulted in improper assembly! I have now followed the instructions and heated the hot end up to 300°C (!!!) and tightened the nozzle against the heat break. I have a small space between the base of the nozzle and the heating block as instructed. Got everything back together and I am now printing again. I should be good.

I'm loving that pointy little nipple on the nozzle! Nice and clean.

What was the best way to get the PLA out of the heat block and nozzle?

[Nylocke]

I had some junk PLA suck in mine and I took the nozzle off and put it in the oven at 500F+ and that cleaned it out well.

[Eaglezsoar]

I had some junk PLA suck in mine and I took the nozzle off and put it in the oven at 500F+ and that cleaned it out well.

Thanks, that's 260 degrees Celsius so when Michael took his E3D to 300 Celsius it should have burned out the PLA.

[mhackney]

I didn't want to risk having char in my nozzle and hot end so I did the best I could to clean things out first. Here's how I did it.

I heated the hot end to 180°C so I could remove the nozzle and the heat break. I then let it cool. The heat brake and nozzle had PLA on their threads which simply pealed off. Nothing inside the heat block or heat break. I then heated the block up to 190°C. When it was hot, I laid the nozzle in its hole tip side down. That let the nozzle get up to temperature but allowed me to access the backside. When it was hot, I removed it, held in pliers, and waited 30 seconds. I then jammed a 4" piece of PLA in the back side towards the tip opening. I allowed this to cool and made sure that the piece of PLA was fused in place (it feels "stuck" in there). Then I repeated the heating but this time I held the nozzle in pliers and pulled gently on the PLA. At some point the PLA in the nozzle, now fused to the 4" piece, started to pull out so I continued to pull a long (12") strand of PLA out. If you use a different color for the 4" PLA you can see what you are pulling out. When it finally all came out, the nozzle was relative clean. I could see light through the opening.

Hard to explain, easy to do!

[626Pilot]

What was the best way to get the PLA out of the heat block and nozzle?

Fire. Takes a few minutes and then you have a clean part. Just don't overheat any of the aluminum stuff beacuse eventually it could get brittle or deform. I use my stove in "blowtorch mode" but if that wasn't available I would use a brazing torch or similar. All you need is heat and some pliers.

[mhackney]

This is interesting and worth knowing about.

I am in "production printing" mode printing my Tenkara Line Holders:
[img]http://mhackney.zenfolio.com/img/s5/v12 ... 6832-3.jpg[/img]

This means that I print, remove parts, and print in quick turn-around cycles. At the end of each cycle, Repetier Host turns off the heaters (like it should) and I quickly turn them on and start another print - after removing the parts of course!

Well, I have this down to an art and my turn around time is something like 10 seconds. In that 10 seconds, the nozzle actually cools enough to "freeze" the PLA but the heater block is still very close to print temperature. So, upon restart I was getting the "Tat, Tat, Tat" from the EZStruder skipping steps, but only for a few seconds and then everything was fine. It took me a little while to figure out what was happening!

Now I turn on the hot end and bed heaters BEFORE removing the parts and restarting the print cycle and all is well.

[mhackney]

Ok, I want to go on record and clear up ANY concerns folks may have about the E3D's ability to print PLA. There may have been issues with version 4 but I can unequivocally state that version 5 is the best hot end I've used (and I've tried 6) and after at least 100 hours of nearly continuous printing with many different PLAs I have not had a single hot end issue - no plugging, no dribbiing/drooling, and no stringing (even on a particularly nasty yellow PLA that always strings. This is simply one fen hot end. I'm really looking forward to the water cooled 4 nozzle Kraken that has a similar SS heat break design.

[altarke]

Ok, I want to go on record and clear up ANY concerns folks may have about the E3D's ability to print PLA. There may have been issues with version 4 but I can unequivocally state that version 5 is the best hot end I've used (and I've tried 6) and after at least 100 hours of nearly continuous printing with many different PLAs I have not had a single hot end issue - no plugging, no dribbiing/drooling, and no stringing (even on a particularly nasty yellow PLA that always strings. This is simply one fen hot end. I'm really looking forward to the water cooled 4 nozzle Kraken that has a similar SS heat break design.

I was wondering what is your retraction settings for the e3d hothead for PLA prints?

[mhackney]

For most of the PLAs I use 2mm retraction and 1mm Z lift. For that gnarly yellow, I use 4mm retraction and 1mm Z lift. No wipe. This is in KISSslicer.