Silicon hot-end "socks" are a heartache waiting to happen  

Re: Silicon hot-end "socks" are a heartache waiting to happen

And that is the reason, why they aren't includes in the kit. It's not so reliable. And without them it is no problem to clean dirty (hot) headblock with brass brush to get almost a new look. No problem with this so far.

Re: Silicon hot-end "socks" are a heartache waiting to happen

Disagree. They are very reliable if you know what you are doing.

Was that the orange volcano sock (next to impossible to remove), the new V6 style socks (the one with the two big holes), or the old V6 with the small nozzle opening?

Old V6 style can exhibit this, but i've been using these over two years (only around 4 per machine in two years, been printing non stop) without any problems until i found out that i've been buying the wrong socks. Even then only one time a sock came loose any it lay on the print bed next to a slightly damaged print.
New ones with the big holes for the screw head and the whole nozzle don't have the "bending slightly backwards and undressing on a sharp print" anymore.

Volcano socks are very hard to get on and next to impossible to get off by a sharp overhang.

The nozzle sock will only show problems when something's really wrong with your print settings, either parts are not sticking doe to dirty beds, or you get sharp overhang spikes due to insufficient cooling.

I've seen many Prusa owners cry bloody tears when this happens:

On why Prusa has found them not reliable and does not include them in Kits, my guess is that they tested only the old style V6 socks.

Won't ever be using a heaterblock without a nozzle sock.
Running 4 Prusa machines almost 24/7, 3 at work and 1 at home, all have nozzle socks. Socks will only get exchanged if i change the nozzle and notice the socks became discolored or slightly brittle.

Then there's the trick where you tie them via a piece of wire at the top of the heaterblock so that they won't slightly bend due to the heat.

Re: Silicon hot-end "socks" are a heartache waiting to happen

Was that the orange volcano sock...?

Indeed it was. I didn't take a photo, but the situation was much like the photo you posted above.

I'm glad you disagree, because that means I might learn something from this thread.

What do you like about the hot-end socks? I got it originally because my hotend wasn't keeping a stable temperature (which, I think, indicates that the PID isn't working so well, even though I did explicityly tune it). It turns out that if too much air is blowing on the hotend from the part cooling fan, then that can happen. But aside from that, I don't see what the benefit of it is. Is that your reason for liking them? Or are there other benefits?

Re: Silicon hot-end "socks" are a heartache waiting to happen

What do you like about the hot-end socks?

posted this a while back:
https://shop.prusa3d.com/forum/others-archive--f66/why-do-these-printers-still-not-ship-with-hotend-s-t14391.html

- most RepRapers cannot design a decent filament cooling solution without blowing cold air onto the heaterblock, and that includes Prusa Research
According to a few people Prusa uses 40Watt heater cartridges instead of now standard 30Watt ones to counter the effect of the air blowing onto the heaterblock, to keep the temperature somewhat normal.
- small stuff like PETG stringiness will get to the naked heaterblock like a magnet, resulting in quite some accumulation after every print. Bigger blobs will attract even bigger stray filament, it's like a game of agar.io These will either fall down to your print resulting in a defect area, or catch the print entirely.
- completely lifting models of the bed will usually get pushed off the bed entirely with a heaterblock+sock (or the pinda), since there's no hot sticky surface for them to catch on to
With a naked heaterblock and a loose model, well, hope you brought lots of time and spare parts.
- PID is a lot more stable
- You need about 4-6 watt less power when printing, since the sock shields the block from cold air (especially on the stock Prusa hotend design)
- Socks will last months. Printing to fast results in sharp overhangs that will damage it, shift it or completely remove it, resulting in the problems you described.
- A heaterblock that get regularly brushed off with rough brushes loose their shiny surface, resulting in even quicker accumulation of molten filament on them. You are worsening the problem with every clean. There's a reason why the heaterblocks are polished.
- E3D includes them with every hotend they ship.

>> Was that the orange volcano sock...?
> Indeed it was.

My respect and astoundment if you got one of these to peel off.
No offense, but i think that means there's something fundamentally wrong with the way you print, either too fast so that cooling does not keep up, resulting in sharp overhangs, or the bed is not clean enough to let parts not stick as they are supposed to. (tried acetone to get rid of finger residue?)

Re: Silicon hot-end "socks" are a heartache waiting to happen

I prefer using a sock just for temperature regulation- especially with TPU filaments. I have had the fan cool the nozzle so fast the heater could not keep up and then....a jam....followed by spaghetti out of the side of the extruder assembly.

Especially useful if you use a copper heater block, since copper is a better thermal conductor.

Aluminum- 215W/mK (watts / meter Kelvin)
Copper- 385W/mK

Meaning copper absorbs heat over 50% better.... which should alleviate the possibly large temperature swings that are possible with even a well tuned PID

I also use a piece of twist-tie around the sock, above the wires (burn the plastic from the wire) to ensure the it's placement.

Re: Silicon hot-end "socks" are a heartache waiting to happen

I notice you're not using any cooling ductwork. I've lately been doing the same, and at least so far I haven't missed it.

Re: Silicon hot-end "socks" are a heartache waiting to happen

I notice you're not using any cooling ductwork. I've lately been doing the same, and at least so far I haven't missed it.

I took the fan nozzle off just for the picture of the wire...

Re: Silicon hot-end "socks" are a heartache waiting to happen

Would it maybe be a good idea to wipe some silicone oil onto the surface of a sock every now and again to keep the surface from becoming susceptible to gathering stray plastic?

I have seen where some PETG stuck to my hot end sock (a light blue E3d sock), and stuk pretty aggressively. I'm thinking the thin coating of silicone oil will keep that from happening again maybe. I'll report back in a week whether it had a positive effect (i.e. reduce the build up).

Re: Silicon hot-end "socks" are a heartache waiting to happen

Then there's the trick where you tie them via a piece of wire at the top of the heaterblock so that they won't slightly bend due to the heat.

I've had good luck adding a few drops of high temp silicone rtv under the suck to glue it in place. Kinda deforms it when you peel it off but e3d says they're only supposed to last a couple hundred hours anyway.

Re: Silicon hot-end "socks" are a heartache waiting to happen

I prefer using a sock just for temperature regulation- especially with TPU filaments. I have had the fan cool the nozzle so fast the heater could not keep up and then....a jam....followed by spaghetti out of the side of the extruder assembly.

Especially useful if you use a copper heater block, since copper is a better thermal conductor.

Aluminum- 215W/mK (watts / meter Kelvin)
Copper- 385W/mK

Meaning copper absorbs heat over 50% better.... which should alleviate the possibly large temperature swings that are possible with even a well tuned PID

I also use a piece of twist-tie around the sock, above the wires (burn the plastic from the wire) to ensure the it's placement.

I'm back to using the sock on my volcano, because it's the only way (currently) to ensure a stable temperature on the hotend while the fan is blowing.

Is the point of the wire merely to hold the sock in place, or is it to prevent catastrophic upflow of extrusion? I actually haven't had any problems with my volcano sock moving or slipping off, per se.

Re: Silicon hot-end "socks" are a heartache waiting to happen

Yes David, the wire is just to ensure the sock's placement. The blue E3D socks do not always fit the best after a number of heat cycles- the volcano blocks fit differently, and better IMO

Re: Silicon hot-end "socks" are a heartache waiting to happen

When I fitted my plated copper nozzle and heater block I initially ran without the sock.

PLA was very nice and temperature regulation was good. Then I switched to PETG and immediately began ripping the first later. As this was being caused by PETG being attracted to the hot nozzle first I turned the temperature down as far as possible. When this was not enough the sock went on. The sock improved things but not quite perfect the final tweak being slowing the first layer even further. Because it is the hot nozzle that was causing the ripping problems only a professional sock would do here.

I may now I have slowed down the first layer enough to be able to run without a sock. However although PETG slides of the plated copper better the nozzle and block was still being splattered. So I will still be using the professional sock when printing PETG.

I have only had one blob of doom and that was on a sock that was worn and should have been replaced.

Regards,
Martin

Re: Silicon hot-end "socks" are a heartache waiting to happen

Love my socks. Wouldn't go without them.

Re: Silicon hot-end "socks" are a heartache waiting to happen

My blob count just went up to 2. Well attempted blob as I stopped it very quickly. The sock was not seated properly and the rear right corner dragged.

Regards,
Martin