New PEEK

[Sandtoe]

I was having some trouble printing PLA and put it over here http://forum.seemecnc.com/viewtopic.php?f=54&t=4312 because I thought some of the picture may be helpful to others. Anyway...I ordered a new PEEK from SeeMeCNC. I thought I should have one since I print close to 230 a lot. But my new peek is different from my old PEEK. It appears to be only big enough for a 4mm tube at the top of it and there seems to be some room for a 5-6mm tube around it at what I think is the bottom connection. Not sure of the set up for this. But perhaps this will fix my PLA woes from above other post.
I assume the first picture will connect to top of hot end (Bowden side) and next pic will connect to lower end (Nozzle Side). Does anyone have experience with this PEEK. I didn't see anything in the forums per say. Thank you.
Top view assumed

Top of PEEK assumed

peektop.jpg (21.25 KiB) Viewed 6369 times

Bottom View assumed

Bottom of PEEK - assumed

Previous PEEK Setup ( like this pic from a previous post)

http://forum.seemecnc.com/viewtopic.php?t=2254&p=16132

I had this setup where to PTFE tubes ran through the PEEK.Sandtoe Plasticator Posts: 5Joined: Tue Feb 11, 2014 11:10 pm

[enggmaug]

I don't understand.

My Rostock was delivered in oct 2013, and my Peek was alike your "new" Peek. It was fitted with 2 PTFE tubes, a short 6mm cut opened, and a longer 4mm in which the filament ran through.

After I melt it, I received in december 2013 2 Peeks that look alike your "old" peek design, needing only one PTFE tubbing.

There are obviously 2 differetn designs for PEEKS, but what I believe is the old one is the one you just received.

[Sandtoe]

On the PEEK with only one tube. Do I install a very short amount PTFE tubing at the bottom nozzle end to fill that small gap or leave it empty for the setup?

Does/did this style PEEK that has only one tube have more or less jamming/clogging issues? Did it melt more easily? Wonder which is the preferred PEEK? Wonder which would transfer the least amount of heat to the Bowden PTC connection? Is there a consensus in the forum on this as I haven't seen any other posts on this but maybe I used the wrong search terms. Thanks.

[geneb]

The "old" PEEK section is designed to use two PTFE liners - a small inner and a split, larger outer.

The "new" PEEK section is designed to use a single PTFE liner and is more aggressively bored to give an air gap around the top end of the nozzle to help reduce jamming issues.

If you don't have a PEEK fan installed and running, it WILL jam with PLA, no matter what.

If your PTC fitting at the top is getting hot, chances are your hot end is currently on fire, and the reason for the heating should be pretty obvious.

g.

[Sandtoe]

Thank you Gene for replying. I think you confirmed that I have assumed the correct setup pictured above so that is helpful as I was not sure. So yes I do use a PEEK fan, and I agree my jamming issue most likely occurs because the hot end it to hot for the PLA. Now I have done some research on PLA hot end temps but it does not always replace experience. When I was pushing filament through the hot end by hand and lowering the temp to find the low end of where the filament melts and where it gets difficult to push I had a hard time determining what is hard to push verse smooth to push. I settled for 195 (perhaps high from what I have read where most use 165 to 180) and my jamming issues occurred because the PLA seemed to soften enough after about 18 lines of g-code or so that it twisted inside the space of the PTC connection where it leaves one 2mm bowden tube and enters the hot end 2mm tube. It would seem that this PEEK and lowering the hot end temp should eliminate this issue. Would there be any other factors mechanical or other that I may have over looked. Thank you. I know these are the same questions this forum gets over and over. Many different answers because, well, there can be many variables. If the answer is, you need to find what variables work for you so the PLA does not jam, then I will keep working at it. Again thanks for the advice it helps to remove my doubts when I hear others peoples experiences and opinions.

[geneb]

Just to make sure I'm understanding exactly what that photo above shows, can you take a photo of the hotend and add an arrow that points to the exact spot where this "twisting" is happening?

tnx!

g.

[Sandtoe]

The filament is twisting in the top of the hot end. Inside the red box between the gap that occurs between the 2 PTFE connections. Now this is with the old PEEK. Tomorrow evening Friday I will set it up with the "new' PEEK I received in the above pictures. Perhaps that will correct my issue. All advice welcome. Ty.

[geneb]

Have you verified your thermistor readings with a thermocouple? Even after hours of printing, that fitting should be no more than warm to the touch.
g.

[Sandtoe]

Hi,
I solved the issue by moving the FAN to heat 1 on the board. Thanks.
The only thermocouple I have is for a kiln and it didn't verify the temperature very well. I am not sure on the plus/minus of it's accuracy.

Thermocouple reading when hot end set at 230

But your comment brought me to thinking about measuring the temp at the area of issue. These measurements are in F and not C.

F Temp at PTC connection with old PEEK at 230C no fan

F Temp at PTC connection with new PEEK at 230C no fan

F Temp at PTC connection with new PEEK at 230C with fan running high

PLA softens around 138 Fahrenheit
The top two are expected without the fan running. The last really surprised me showing how much the temp is reduced running the stock fan with the repable fan shroud. It was these pictures that had me thinking about my fan setup. I believe the instructions and this site have a lot of information about fans which I read but temp differences didn't really hit home till I saw above. I had it set to turn on and off with the start of a job in slicer. I changed it to the heat1 spot on the board to take advantage of the Eeprom settings controlling it with the hot end as being on or off. I made the wrong choice in setting this up and didn't fully understand the highlighted section in the manual in regards to the choice I made. Now that I set it this way I have not had any rotational jamming due to temp creep and I don't expect any in the future. thank you. And thanks Gene for continuing to answer the "usual questions"