FIRE CLEANING Filastruder Wall Contamination - [ Filastruder Renewal ]

How do you deal with the loss of Temper in the metal?

-os3dp

Hi os3dp,
Sorry I should have mentioned 1000°C is on the flame temperature, The metal itself was around 500°C , So the tempering isn't significantly affected .... but is better than throwing it out or giving up.

CFTechno
We used masterbatch from a supplier in China. Came as a Free sample for PA747, apparently for ABS use.
Apparently that was what our agent said... Carrier MG94 and PA747, tried both and jammed. but we discovered the carrier didn't matter as it was the masterbatch pellets that scrapped against the wall and created that 'oxidized or hardened' layer which affected flow,

"Could it not be that the switching plastic types "-Yes possible, but so far we use ABS+ Polycarbonate without issues.

The key point of this post is :

""" If all Hope is lost, use fire to reset it, it's better than throwing out the filastruder "

Generally, the purpose of this post is to advise a way to use fire to clean out experimental "trial" chemicals or polymers.
So you can experiment without fear or worry that it'll ruin the filastruder shaft, because fire cleans out plastic polymers really well.

So we hope it helps those who have all but given up or are fearful of experimenting.
We're letting you know that there's a confirmed solution

Cheers

i'm more afraid of burning plastic fumes than experimenting.. i usually use fire to clean/remove the screen on the melt filter.
this isn't practical for 1+2 but i'll be using 3 for test filaments and i'll prob be torch cleaning it, 3 also extrude outside. 1+2 for abs/pla

good posts just remember everyone's setups are different and its always gonna be about what works best for you.
kind of the fun of it is figuring that out.

Just tried this after some running some bad masterbatch through my filastruder - it certainly works and beats the alternative of having a non-functional machine.  My extrusion rates are back up to what they used to be and I'm very happy I tried this!

I am totally new to the forum and in fact still waiting for our own filastruder to arrive, so please excuse me if this information has been posted before: I notice a lot of people having trouble cleaning between batches and/or colour changeovers: In an industrial environment dies and other parts are cleaned in a furnace by pyrolysis (= simply HEAT) but it is a very, very controlled environment. Torching clogged parts may seem be a solution to remove residue but to me it looks like really wild and  uncontrolled.

Even if industrial extruder components can be cleaned by pyrolisys, operators tend to avoid this because it complicates matters and one ends up with burned residue which has to be removed anyway. Using a purging compound is the best solution to remove pollution and to clean out the barrel/screw and die between colour or product change-overs and also as a regular maintenance habit to keep things clean and shiny.

I have seen posts that mention the use of ready made so-called purging compounds which  are offered on ebay and the likes but these products are usually too weak to do anything more than to keep a clean barrel clean for a little longer. What you people probably need is a real industrial purging/cleaning compound: one that lightly foams up once it is inside the barrel: that feature, combined with its ability to rub off residue and polish the internals is what is going to make your life easier.

We use several types of these compounds on Industrial extruders: some are universal type and are to be mixed in small quantities into the polymer granules that you are using whilst other types have been specially mixed for a specific application. When our filastruder will be up and running we intend to try the different types of compounds and will report on the outcome to the forum.

Being friendly with our supplier, we might even persuade them to make a "special brew" for filastruder use and he may even be persuaded to supply the product in small quantities especially for filastruder use - These outfits traditionally only sell by the pallet-load to the plastic industry and that's probably why this type of product has not yet been discovered by private users.

Would the community be interested in our findings?

I think the trick with using a purging compound with a Filastruder is knowing when the purging compound is purged.  Does it get purged itself effectively by the next plastic, and are there compatibility issues between compounds and the plastics that follow?  I've found that switching from ABS to PLA can be tricky because bits of ABS can show up intermittently in the PLA some time after it seems like it has been purged, depending on temperature.  I noticed that at lower temps the PLA would drag out burnt bits of ABS while at higher temps the PLA seemed able to slide past it.  I wonder if there would be similar concerns with purging the compound.

Basically we have the use of two main types of purging compounds:
1./ a concentrate that can be mixed through any polymer that you use: I believe this would be a very good choice for filastruder applications as most filastruder users seem to be switching grades and colours a lot: the liquid concentrate would give them the freedom to mix their own purging compounds at will: mixed into the polymer grade of choice at a ratio of some 4 pct the compound then passes through the machine: It relies on physical properties (I avoid the word "chemical" because that idea frightens off people without reason) to rinse and polish the screw, barrel and die. As it foams lightly it also reaches into nooks and crannies inside the machine.

2./ A ready-made compound that is specifically mixed for a specific purpose: these compounds come in the shape of ready to use pellets and can be made very potent to remove difficult polymer-residues or notoriously stubborn colours. The product usually foams and maker can even decide to mix fibreglass into the compound to make it more effective. This may be less universal than the Par 1./ solution in a filastruder environment. Plastics processing plants usually work withing a limited range of polymer grades and these may prefer a tailored purging compound.

As mentioned our own filastruder is not yet delivered so I am not yet able to check if the set of rules used in the Plastic Industry also apply to the filastruder but I am determined to find that out for you - I've also received some kind messages from individual community members offering to test on their equipment and that might be a intermediate solution, provided said memebers would be willing to share their findings and recommendations.

This is going to be very interesting

Assuming you remove the thermocouple and heater, all of the materials on the auger/barrel/flange/coupling/nozzle are either

steel
stainless steel
brass

So you should be good up until around 800C.

For any/all interested, I have had success cleaning my Filastruder nozzle, couplings, etc. at 500C for anywhere from 6-9 hours, leaving them to cool slowly overnight. I understand not everyone has access to an oven that gets to these temperatures, so YMMV.