Reprap Forum - Plastic Extruder Working Group

Single Screw Extruder Barrel Pressure (no replies)

gaurangsk — Wed, 27 Mar 2024 21:24:40 -0400

I have a low grade single screw filament extruder which has a 16mm dia and 210mm long barrel. Over the time, the barrel walls have become oblong (not perfectly cylindrical). I wish to replace the barrel on the extruder and was wondering what pressure would be generated inside the barrel so as to cause the problem. Would appreciate any help to get an idea on the pressure values so as to choose the correct barrel for the extruder.

Extruder Operator Wanted! (no replies)

Innovate Recycle — Thu, 14 Jul 2022 13:36:52 -0400

Hello,

Thinking out side the box, I’m trying to recruit an extruder/pelletiser operator for our new facility in Northampton (NN5) area.

Innovate Recycle (www.innovaterecycle.co.uk) is a first to market carpet recycling company that requires a highly experienced extruder/pelletiser operator to guide and grow the company as we process polypropylene carpet waste with proven proprietary technology.

If you are interested, or know of someone this opportunity may suit, please contact me via email with a CV details below.

We are looking to make a swift appointment pending the right applicant.

Many thanks in advance

Joe Eccleston

Email -info@innovaterecycle.co.uk

Choppy Remote Drive Shaft Normal? (no replies)

Power3DPrinting — Thu, 28 Jan 2021 13:48:24 -0500

Hey, just a question to anyone that has used a remote drive extruder but is the shaft supposed to be choppy in its tubed/sleeve? The shaft itself is plenty rigid but when I turn it by hand it takes quite a bit more force to turn it 180 degrees than the following 180 degrees to complete a 360 degree rotation. Is this normal?

Valved Bowden (7 replies)

Regicide — Thu, 25 Feb 2021 22:28:08 -0500

For a long time, extruder weight has been a compromise. Direct drive is heavy but grants greater capabilities to actual extrusion, while Bowden is light but sacrifices print quality and reliability. It’s time for a change. I call my concept a Valved Bowden, although truthfully, it’s a direct drive extruder being fed by a Bowden. Let me explain.

Direct drive weights are being reduced with gearing and smaller motors, but we are still a lot heavier than we could be. The main problem is that a lighter and smaller extruder has trouble supplying torque. My Idea was to find a way to assist a smaller motor. Bowden extruders can print without any direct drive assistance at all, so if a Bowden extruder is added upstream, an extruder with much less torque can be used and still produce reliable print results. I found a NEMA14 ultra thin stepper motor for PTZ camera - RobotDigg which weighs just 60 grams but still supposedly outputs 500g/cm of torque. That’s not enough for traditional direct drive, but could potentially work to control the end of filament and reduce slop. That’s why I call it a Valved Bowden rather than a hybrid design: it’s really more of a Bowden design. I’m going to work towards refining the idea, look for more updates soon!

Viscosity the amorphous polymers (1 reply)

doug20 — Sun, 06 Sep 2020 16:35:24 -0400

Hello! I am looking for the apparent viscosity values at the melting points of the ABS, PLA and PETG polymers, which are most used in the production of 3D printing filaments. I would like to calculate the theoretical flow and pressure for my project, considering the Newtonian fluid and the linear pressure variation. Is it possible to get the results this way, or are there other ways that I can't find?

Thanks in advance!

extruder filament sensor (1 reply)

SvRc — Fri, 30 Oct 2020 08:46:10 -0400

Hi, i am new in this forum by the way sorry for my english.

I constructing filament extruder in marlin firmware like this [www.youtube.com] , but i don't want to use lyman filament sensor [www.thingiverse.com] , the sensor which i want to use [electronoobs.com] that you think its good idea? lyman sensor use analog input, sensor that i want use digital, any one can help me with programming?

I was looking for finish code but didn't find it anywhere in Marlin-Mackerel-master arduino code >> pins.h need new pin like #define FILWIDTH_PIN_CLOCK X code >> temperature.cpp its sensor directory code keys word (current_raw_filwidth, FILWIDTH_PIN, current_filwidth, raw_filwidth_value) can any one help me with coding.

the code there you can download [github.com].

Filament Diameter Measurement (no replies)

hari3d — Wed, 08 Jul 2020 05:11:20 -0400

Hello, I am using the marlin realtime filament diameter measurement to controll variable extrusion speed.
Now I need to get the read filament diameter to a txt file to sd card.

How to do it. I am using "Marlin 1.1.9.1"

Please help me.

I made some PEEK filament and did a quick write up on it (2 replies)

Ggalisky — Wed, 11 Mar 2020 13:36:02 -0400

DIY Filament Review for PEEK (Polyether ether ketone)

Source of pellets: [www.filastruder.com] … al-pellets
Note, I emailed elmoret(Tim) and he was able to order these pellets very quickly(<1 week). Thank you Tim!

Pre Drying instructions: I used a toaster oven at 150C for 4 hours -see figure 1. Not sure if this was overkill, but it worked and the filament was dry enough to print with. After the pellets were dried I let them cool down, put them in a ziploc back, and loaded them into my hopper 3 days later.
[imgur.com]
Figure 1: Pellets in oven
[imgur.com]
Figure 2: Pellets in bag

Filament extrusion setup: Filastruder with frankenstein Filawinder built from scraps in my shop - see figure 3

Note, the Filastruder has been modified to have 18v supplied to the heater and 12v to the motor. This allows me to reach 350C+ extrusion temperatures. I also added glass fiber insulation to the end of the thermocouple as the the PTFE insulation is not rated past around 200C

I also built airtight silicone sealed hopper and attached that hopper via drilled and tapped M3 holes on the barrel of the Filastruder.

The plastic box around the Filawinder was an attempt to make it easy to seal off spooled material from the outside humidity.
[imgur.com]
Figure 3: Filastruder and frankenstein filawinder mounted on plywood
Extruder settings:
Extrusion temp 345C
Extrusion rate: 13in/min - This is about 1kg per 2.5hrs I think.
[imgur.com]
Figure 4: PEEK filament

Machine used:
Custom Big Fused Filament Fabrication 3D printer, CoreXY with 21.5x12x18in build volume, heated bed, heated chamber, flexible thermal barriers, E3D Titan Aqua, E3D super volcano, E3D .6mm copper plated super volcano nozzle, PT100 temp sensor, Duet Wifi, Nema 23s, Ball screw for Z, removable spring steel build plate held on by high temp magnets, PEI build surface.

Machine settings:
Print temp 370C Nozzle, 150 bed, 70C chamber
20mm/s 100% infill, 2 walls
[imgur.com]
Figure 5: Custom BFP (Big FFF 3D printer) printing a PEEK double helical gear

DIY PEEK Filament Tolerances: 1.62+/- .8mm NOTE: I am still working on getting the tolerances right, but I am confident I can get it to +/- .1mm. My filawinder setup is hacked together incorrectly and needs to be rebuilt to get better tolerances. I will post an update when this is completed.

Printed part: I opted to go with a very small test print so I wouldn’t have to worry about warping. The test part is a scaled down version of a Filawinder drive gear. The top part of the print had very poor layer bonding and confirms that in order to properly print PEEK you need to have the ambient air temp around 130-140C. Having the ambient air temp near the glass transition temp of the plastic helps with layer bonding. This is why large ABS parts from Stratasys printers never have layer separation mid part. Since my chamber temp was around 75C the layers cooled down too quickly and were not “sticky” enough to bond to the next layer. Also a word of warning, the part stuck too well to the PEI build plate - see figure 7. In the future I will be using a piece of steel with PVA glue on it and seeing what happens. I will post an update when I print with different chamber/ bed temps.

[imgur.com]
Figure 6: Printed PEEK double helical gear
[imgur.com]
Figure 7: Poor layer adhesion
[imgur.com]
Figure 8: PEEK part sticking too well to PEI build surface

An interesting note:
Something that I found fascinating was that when the filament was extruded it came out semi clear brown and then as it cooled it hardened into light milky brown - see figure 8. This occurred both on the printer and Filastruder. It was more clear when extruded on the printer. This may be due to the higher extrusion temp (370C vs 345C).
[imgur.com]
Figure 8: Filament color and opacity change, clear brown filament section is circled in blue

In conclusion:
My initial testing is very promising. With some more testing and higher chamber temperatures I believe I will be able to start making larger PEEK parts with strong layer bonding in no time. As it stands now I need to fix my winder system to get better tolerances, but there is no reason that I see beyond my winder issues that would make it hard to get +/- .05mm tolerances. I will be updating this thread as I get closer to establishing a proper workflow for PEEK. Thanks for reading! If you have any questions or feedback feel free to post below or PM me.

dualExtrusionSingleNozzle (no replies)

herve robert — Sun, 24 Mar 2019 07:44:58 -0400

with the dual hobbed extruder: https://reprap.org/forum/read.php?1,840705

doesn't really work.. too much strings..

here my scad files:

https://www.dropbox.com/s/ks90mbvuxvo22tr/dualExtrusionSingleNozzle.tar.gz?dl=0

[attachment 110676 pic1.png]

[attachment 110677 pic5.png]

some infos: http://wiki.3dator.com/index.php/Dual_Extruder_single_nozzle/en

Rotary tumbler - anyone use for 3d prints?? (2 replies)

krakow2000 — Fri, 22 Jan 2021 08:53:22 -0500

Rotary Tumbler - found couple movie, foto, info about this but anyone use this to "polishing/post-processing" 3d prints?? If "yes" tell what "abrasive" you use??

extrude HDPE-PET mixture (no replies)

hameed — Mon, 22 Oct 2018 13:53:10 -0400

Hi everyone

Could anyone please advice me if it is possible to extrude profiles of HDPE-PET mixture? will there be any processing difficulty during the extrusion process?

TIA

Isomalt (sugar alcohol) for Printing and Support (1 reply)

dgm3333 — Sun, 30 Sep 2018 02:15:16 -0400

Obviously sugar isn't plastic, but this technique seemed most relevant for this section

Just found this article using isomalt to develop structures:
[news.illinois.edu]

Isomalt:
Costs approx £10/kg
Melts at around 150degC
Cools rapidly enough it can be printed in midair.
Dissolves rapidly in water
(would probably be recyclable if you break off and reform the syrup, although I suspect would yellow with repeated use, and you might get hard "burnt" deposits which could clog the nozzle)

This is a bit about preparing syrup: [www.wikihow.com]

I'm just wondering if anybody is working on anything like this?

Given a viscosity is it possible to calculate required pressure for desired output? (2 replies)

CharlesDesign — Thu, 06 Sep 2018 17:01:25 -0400

Hi All,

I have a setup similar to the one pictured and I'm trying to figure out what kind of pressure I need to deliver the throughput.

Is there a formula that'll predict throughput based on pressure and viscosity?

Thanks,
Charles

exdierod.jpg

Piper3dGW extruder on Thingiverse (no replies)

piper3d — Sun, 20 May 2018 22:54:33 -0400

[attachment 105053 new_extruder_2018-May-19_01-11-48AM-000_CustomizedView87308378.png]
Have uploaded my version of Greg Wade's extruder [www.thingiverse.com].
Running 4 of those on my printers. May be used as direct extruder or Bowden.
Includes F360 file so you guys may continue improving it.

Poll: what are your hotend heat up times? (5 replies)

VladCronos — Wed, 18 Apr 2018 02:28:10 -0400

Hello everyone,

Would be interesting to hear what is your hotend heat up times.

1. 25-200
2. 25-350
3. 25-500 (if applicable)

Here is my data:
1. 20s
2. 35s
3. 50s

I really want to know what industry average is and what is considered standard.

Thank you in advance for participating in my poll :)

The 0.8mm filament experiment (11 replies)

o_lampe — Thu, 31 May 2018 02:51:52 -0400

Hi everyone,
as we know, the step from 3mm to 1.75mm filament changed 3DP a lot. I always thought, it could get even better with thinner filament. Mostly reducing extruder weight is the goal in this experiment.
I started to make my own 0.8mm filament, simply by extruding 1.75 filament through a 0.6mm nozzle, while the printhead made continuous circles.

Why 0.8mm? It fits nicely in 1mm ID PTFE tube and I could easily modify a 0.4mm nozzle with a brass tube of 2x0.5mm.
So I took a MK8 direct drive extruder, pushed the 1mm ID PTFE tube into the standard 2mm ID PTFE tube of the heatbrake.
The drive gear had way too much pressure and almost bit through the filament, so I took a smaller drive gear and added two layers of shrinktube. I also had to replace the grooved idler gear with a flat one.
A NEMA17 1.7A motor had no problem at all to extrude at 15mm/s. The cross section is 5.4 times smaller, so I guess the required torque can be 5.4 times smaller, too? I ordered a NEMA17 20mm pancake ( weight 140 gram ) with 13Ncm holding torque. ( a bit different to the pancake E3d uses for their Titan extruder. )
It will surely do the job, but I'm tempted to try an even smaller stepper, like the 14HR05-05A ( weight 50 gram ) with 7Ncm. Maybe add a 3:1 gear, like a tiny Titan. It would then be ~100gram lighter.

I already tried to extrude with a modified 28BYJ stepper, but it was a little bit too weak at 500mA.
[attachment 103761 2018-03-2715.38.42.jpg][attachment 103760 2018-03-2715.46.14.jpg]

I'll post a video of filament making later. Here it is

Drilling and Tapping filament (no replies)

dlw — Thu, 11 Jan 2018 16:35:15 -0500

What are the best filaments for Drilling and Tapping?

dlw

DIY DYE (1 reply)

hexes — Sat, 25 Nov 2017 15:05:53 -0500

Hello, all! My name is hexes and I have a project.

The newly-announced Da Vinci Color from XYZprinting is an idea I had a few years ago, after watching a video from YouTube's own Angus Deveson, or Maker's Muse. The video was about spray painting filament before printing. The flecks of dried paint mixed into the clear or white plastic during extrusion, resulting in colored plastic. I wondered at the time if a CMYK inkjet head could be modified to drop color onto white plastic, resulting in full color prints (or at least any solid color desired). Now, I want to see a Palette-type device become available to the average maker that would work with 3D software to spit out colored results, and I am writing this here because I want the result to be buildable by anyone with the time, desire, and appropriate amount of money.

I am willing to take on most of the legwork for this project, but I need help. I know next to nothing about color slicing, inkjet modification (as may be necessary for powder-based printers), or the code necessary to bridge the two devices. So, if you know anything that might be helpful to this project, pleas let me know in a reply. I'd love to see this idea come to fruition, as I believe that full-color printing should no longer be restricted to a industrial workspace.

Thanks for any help you might be able to give.

-hexes

Looking for hotend blueprints to fabricate (no replies)

Outbound — Tue, 21 Nov 2017 14:22:55 -0500

Greetings,

A friend of mine owns a lathe and he's always on the lookout for interesting projects so we'd like to try and fabricate a hot-end.

Are there any recommendations for an open-source design which we could try and build?

The lathe can also be used as a router and he has some very small diameter drill bits so we were hoping to manufacture everything from the cooling vents, heating block and nozzles. I was just hoping for an established design which we can then easily compare results with.

Thanks.

How to adjust UV resin viscosity ?? (3 replies)

EGPMAX — Thu, 06 Jul 2017 02:54:42 -0400

Hello
Please I need help :S

I have uv resin the viscosity is 3000 CPS ,I need to adjust the viscosity of resin to be 250 CPS How can I do this
without any change in chemical properties ?

THANK YOU

different pellet printer ideas | hotmelt pump (no replies)

DeepB — Tue, 27 Jun 2017 09:30:48 -0400

Hello,

I bought a 3d-Printer some time ago, and am now building another one.

I want to print using pellets instead of filament. I know of the pellet hotend options, mainly with an auger bit.
However theres a catch. I need to melt the pellets, then add non-meltable components, mix, and then pump it to the hotend.
The Melting and feeding I can think of a few ways to accomplish that.
But do you know of an (affordable) pump that can be used in 400°C (celsius, not fahrenheit)?
I thought of an all-metal gear pump, but any suggestions are welcome.

Thanks
Daniel

paper lamination UV Resin for Polymer Clay Dimensional Gloss (no replies)

dhruv patel — Wed, 08 Mar 2017 11:01:31 -0500

this camical is use for paper lamination. [www.youtube.com] in this link you can see how this cemical work. now my question is how i made this camical.

What Filament do I have? (1 reply)

DaHai8 — Mon, 27 Feb 2017 12:48:54 -0500

I bought a spool of Black PLA, but it sure doesn't act like PLA.
It's oily, more flexible, and doesn't want to stick to the build plate (PrintBite) at any temperature combination (bed/extruder)
It doesn't smell when printed and the stated print temperature rage on the label says '190c-210c' which differs from the 'standard' PLA I normally get: 190c-220c
It sorta acts like PETG, but not as flexible when printed - plus I can get PETG to stick to the print bed.
Any ideas how to tell exactly what this is?
Or is it really just crap PLA?
Thanks!

Print PLA into PETG? (2 replies)

DaHai8 — Mon, 06 Feb 2017 03:00:12 -0500

Anyone tried printing PLA onto PETG?
I want to print an object in Black PETG up to a certain layer height and then switch to Grey, but I don't have any Grey PETG. So how about Grey PLA?
Will it laminate?
Anyone have any experience with this?
I've done a couple web searches and come up empty.
Thanks!

Quick Question About Stainless Steel Nozzles (no replies)

Lazerlord — Tue, 13 Dec 2016 12:34:00 -0500

I recently started using some ebay-sourced stainless steel nozzles because of some filled filaments I plan on printing with, but I know that stainless has less thermal conductivity. I printed a temperature calibration piece, and it failed pretty bad, but it looked like a partial clog that cleared itself later in the print is what caused the issue, but I'm not sure if that's actually what happened. With what I could salvage, the layer adhesion at 210C was about the same as the layer adhesion of a brass nozzle at 175C. That seems like a pretty extreme temperature difference, but the poor performance of the stainless nozzle could have been due to whatever happened that caused the print to fail (it was overnight, I didn't watch it).

Basically, how much does a stainless nozzle actually affect print temperatures?

Looking for print cooling solution for E3D V6 (4 replies)

ianmcmill — Sun, 29 Oct 2017 16:34:15 -0400

Hello!

I have been printing with a lot of different extruders and print cooling constructions. Mostly one-sided print coolings. While printing overhangs that are on the opposite side of the print fan, those become not very clean.
I tried several other fan duct cunstructions but never have been happy with their size (bulky) or overall performance.

So while scavanging the thingiverse repository (which is very tideous if you look for a specific thing that meets your criterias) I thought I write a REQUEST/SEARCH post on an "authentic" 3d printer community site which is reprap.org.

What I have tried so far:
My current extruder design [www.thingiverse.com]
Current cooling fan duct: [www.thingiverse.com]

I just printed this: [www.thingiverse.com]
But this is rather bulky IMHO.

I also like to use those 50mm radial fans as they are very quiet.

Any ideas? What do you use?
Do you know the droids I am looking for?

3D printer Ink-Jet binder (no replies)

marziehz — Tue, 04 Oct 2016 04:16:48 -0400

What method and compositions(surfactant and pigment) should we use to make 3D printer Ink-Jet binder (in powder- binder method)?

Please help us.
Thanks so much

Which one is better? Bowden or direct? (6 replies)

Veesta — Mon, 13 Feb 2017 17:01:40 -0500

Hi there,
Question is in the topic tittle.

I have MK8 direct drive extruder and this mechanism can be converted to bowden feeder.

So, would it be a waste of time to try bowden feed extruder at some point?

Why PTFE lined throat instead of metal throat? (5 replies)

Veesta — Wed, 18 Oct 2017 18:50:46 -0400

Hi there,

Yup, dumb question but i'm interested.

My PTFE throat just arrived and i have two metal throats in the box.

What is the benefit for using PTFE instead of metal?

Also, which end is the nozzle? The open PTFE end or the closed metal end?

41ZRkVnCuJL._SX342_.jpg

I'd guess the open PTFE end should be facing the nozzle?

My extruder is the MK8 thingy, which currently has a metal throat from E3D V6 with a heatbreak.

new0.4_2.JPG

Controlling heat distribution in plastic extruder barrel (1 reply)

gstrooder — Sun, 24 Jul 2016 14:10:22 -0400

Hi reprap community - thanks for putting together such an excellent resource in this forum.

I've been working on a plastic / filament extruder build for the past few months to do large scale robotic 3d printing and have come up against an issue with uneven heating of the extruder's barrel. We are using a couple of cheap REX C100 PIDs with K type thermocouples to control 75mm band heaters. We've tried to invest in decent quality heaters - they are probably middle of the range compared to some of the ones you can find on ebay. The control loop itself seems to be OK as the PIDs will manage to oscillate +- 5 degrees around the measured temperature at the thermocouple - we've checked this with another temperature probe and the read out is correct. Unfortunately on the inside of the barrel the temperature seems to spike at the centre of the heater band by about +70 degrees which is way too much deviation to safely extrude plastic. I've made a little diagram that is a guestimate of the temperature profile down the barrel.

I was wondering if anyone had come up against similar issues building their own extruders, or been able to find good ways to distribute heat from the heater bands? The barrel we are using is 5mm thick tool steel - and I am very surprised to find such a huge variation in temperature. Cheers.