PTFE vs PEEK

Anyone tried using PEEK (polyetheretherketone) in place of PTFE for the extruder?

No I had never heard of it before. Looks like a good insulator but is says here [en.wikipedia.org] that it has a glass transition temperature at 130-150C. My understanding is that it will become flexible, possibly rubbery at that point so it may give way mechanically a lot sooner than PTFE.

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[www.hydraraptor.blogspot.com]

Hi Steve,

i made some tests with thin PEEK sheets, on which i placed conducting glue and tempered in the oven at 120

We tried this out. At first I was a little worried about the glass transition thing but after reading up on wikipedia i found out that this is not the melting point...although the article left me rather confused. Anyway...I ordered a 20mm PEEK rod from RS components. here is the link to the product that has a link to the data sheet for this variant of PEEK:

[at.rs-online.com]

According to this data sheet is has:
Max. service temperature
short term

Edited 1 time(s). Last edit at 08/29/2008 06:09AM by wizard23.

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greetings
wizard23
[reprap.soup.io]

Looks good I will have to give it a try.

BTW, the reason PTFE gets longer is simply thermal expansion. You have to warm it up to the extrusion temperature and give it time to expand before you calibrate your z-axis because the amount it expands at 230C is about 0.5mm, more than a layer height.

I also start my raft with a 1mm thick widely spaced base layer with the head set lower. That compensates for a slight inaccuracy in z (my machine frame is wood so it varies with weather). If the head is a little low the first layer has room to expand sideways, if too high it expands vertically. The last layer of the raft is then exactly at the right height and level.

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[www.hydraraptor.blogspot.com]

My Lord, guys! You don't want your PTFE getting very hot at all, the point being that if it does your filament melts in the PTFE or PEEK or whatever before it gets to your heated extruder barrel. That's not something that you want to happen.

Quote

That's not something that you want to happen.

Yes but unless you have a perfect insulator that is what happens. The heater is at say 230C, ABS melts at 105C. so the PTFE is hot enough to melt it some significant distance down its length.

It is definitely molten at the junction of the PTFE and the heater barrel because if you dont seal the thread it leaks out.

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[www.hydraraptor.blogspot.com]

nophead Wrote:
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>
> It is definitely molten at the junction of the
> PTFE and the heater barrel because if you dont
> seal the thread it leaks out.
>
Not in my extruder design. The junction in mine rarely exceeds 80 C.

Edited 1 time(s). Last edit at 08/29/2008 09:23AM by Forrest Higgs.

Yes but then the point that it just melts (and is very viscous) is part way down the copper tube, which is less slippery than PTFE, so it is harder to push. That was exactly the problem I had with my stainless steel version.

Edited 1 time(s). Last edit at 09/27/2012 03:26PM by nophead.

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[www.hydraraptor.blogspot.com]

can any1 tell me how to fabricate PEEK-ALUMINA composites..can it be made by powder metallurgy..if yes, how???