Successfully printing PCTPE!

Here it is, my iPhone 6s case designed and printed by JONESIUM DESIGNS. I used the filament PCTPE by Taulman. Its a mixture between nylon and TPE. This results in a very very strong case that is also flexible. You can also dye them any color you want. I will write a short summary of the process from designing to printing shortly.

My PCTPE settings were as follows:

Hot End: 235
Heated Bed: 95
Print Speed: 50mm/s
Resolution: 0.30mm

3D Printer Blues!

So from time to time we come across difficulties pertaining to the functionality of our Anet A8 printer. Well, last night was one of those times.

i just got done with a successful 3 hour print of a cell phone case with some TPU. The next day I go to print with some plain ol’ PLA and I hear clicking from the extruder. I immediately knew there was an extrusion problem. I had the problem before and it was the hotend getting jammed up because the nozzle was too close to the bed causing the filament to squish itself up inside the throat. I also ruled out temperature of the heated bed and the filament because I use the profile I made up in Simplify3D.

So I re-leveled the bed before calibrating my auto level sensor and retried the 20mm cube print. First layer was fine and then on the second layer it jammed up again. I pull the bowden tube out and clear out the squished filament and I noticed the tube was very warm almost hot. I also noticed the filament was half melted as i pulled it out of the tube. I thought oh this is a different issue here.

I knew from research that the tube passes through the heat,  the heat sink has a fan to keep it cool to keep the filament below the melting point before it is pushed through to melt at the nozzle.

My stock fan was slowly dying and was not able to do that. So I replaced the fan and immediately went back to printing.

Quick Overview of Bowden Setup (with Amazon links)

In order to upgrade your direct drive setup to a Bowden one, you need the following items.

1) E3D V6 type hotend (Here it is on Amazon) $15.69
2) New Modular X-Carriage (Get it HERE on Thingverse) $FREE.99 + cost of filament
3) BIQU 3D Printer Injection Edition Extruder Here it is
on Amazon
) $11.98

4) Extra PTFE Teflon Tubes (Here it is on Amazon) $7.98
5) Bowden Extruder Mount (Find it HERE on Thingverse) $FREE.99 + cost of filament

BIQU Injection Edition Extruder

Changed the direct drive extruder to an extruder more suitable for the Bowden setup. It was very easy to install even though it did not come with directions. I looked it up on google. I think this is a more stable setup as far as feeding the filament consistently.

Here’s some very helpful tips on printing with ABS!

Getting your prints just right can be challenging to say the least. You have to worry about a variety of variables from print speed, extrusion, retraction, bed leveling, etc. One major issue that you will come across is getting the right nozzle temperature and bed temperatures for the material you are printing with. Here’s an article that will help with ABS in particular. I print with ABS mostly just because that’s what I prefer.

https://www.matterhackers.com/articles/how-to-succeed-when-printing-with-abs

 

How To Succeed When Printing With ABS

Last year, we published an article talking about how to succeed while printing with PLA. While we still love printing with PLA, we neglected to write about the sister filament – ABS. Prepare your printer and get a notepad – the time has come.

ABS is one of the most commonly used, and most versatile materials available in 3D printing today. If you’re new to the scene though, it can be a bit daunting to start with. However, the payoff is worth it. Learning to print well with ABS is essential if you want strong, heat resistant parts.

Table Of Contents


Lego bricks made from ABS


What is ABS?

ABS or Acrylonitrile Butadiene Styrene is a common thermoplastic. It’s a popular plastic for injection molding and it’s used to make legos, instruments, sports equipment and more.

If you’re used to printing with PLA, you’ll probably find ABS a little trickier to print with. There are a couple more steps required for each print, and it has a different set of printing settings. However, you need not despair. ABS is a strong and heat resistant filament, with awesome post processing options. With this article under your belt, things will be printing your way.

Getting that first layer right

As we discussed in our PLA article, getting the first layer down is the most important part of the print. Here are the key points:

  1. You need the print bed (or print surface) to be level
  2. You need the extruder to be homed to the correct height from the bed.
  3. You need a good adhesive to assist your ABS in sticking to the bed.
  4. And of course, making sure that your extruder is heated to the right temperature.

Printing on glass with Kapton/PET tape

In order to print with ABS, you need a temperature controlled bed. The recommended bed temperature for ABS is 110°C.

Instead of printing directly on the glass, it’s better to print with Kapton/PET tape. This makes it easier to clean the bed after you’ve been printing for a while, as you can simply remove the tape, clearing any leftover adhesive or filament. For instructions on applying Kapton tape see the video below or read our article: Bed Surfaces – How to apply Kapton Tape

Having your bed level and extruder at the right height is extremely important when printing on tape.  If your extruder is too far from the glass your ABS simply will not stick. If the extruder is too low the glass it will completely block the extrusion of material and may cause a jam after extended periods.

You should also make sure that you have an adhesive of some sort. ABS requires something to bind itself to during the first layer of the print. The most commonly used adhesives are glue sticks, ABS slurry, and hairspray. We prefer hairspray because it’s easy to apply and smells nice. Make sure you get the kind with a plastic base. (We have used “Aqua Net Extra Super Hold”)

If your first layer is not sticking:

  1. Make sure the bed is level.
  2. Make sure the bed is hot enough.
  3. Make sure that the ambient temperature of the print environment isn’t too hot or cold (or else adjust accordingly).
  4. Make sure you put the adhesive on the bed.
  5. Make sure the print head is close enough to make a nice squished first layer.
  6. Make sure you run the extruder enough before your print starts so there is filament going onto the bed during the entire first layer.  In MatterControl you can set how much material you would like to extrude before the print starts, either with loops, or if your an expert GCode commands.
  7. Kapton/PET tape is a great way to print ABS.  It makes a great shiny bottom layer and the heated bed ensures that your parts stay nice and flat.

    For more in depth information regarding ABS bed adhesion check out this article we wrote for more detailed guidance.

Getting the temperature right

When working with a new roll of filament for the first time, we generally like to start out printing at about 230c and then adjusting the temperature up or down by 5 degree increments until we get the quality of the print and the strength of the part to be in good balance with each other.

What to look for

If the temperature is too high:

You will see more strings between the separate parts of your print and you may notice that the extruder leaks out a lot of plastic while moving between separate areas of the print.  If this happens you should try to incrementally lower the temperature by 5 degrees until the extruder is not leaking so much material.

Sometimes you will have a material that is simply less viscous than ABS and will leak more even at lower temperatures.  We recommend you increase the retraction a few millimeters (3-4 seems like a good number for most every ABS we have tried).

If the temperature is too cold:

You will either see that the filament is not sticking to the previous layer and you are getting a rough surface, or you will get a part that is not strong and can be pulled apart easily.  In either case, you should increase the temperature by 5 degrees and try again until you get good line segments on every layer and have a strong part when done printing.

A print gone cold. Check your retraction and heat for clean prints.


Changing filament

When switching ABS colors:

  1. While the extruder is cold set the heat to 120c and wait for it to heat up.
  2. When you reach 120c remove the current filament from the extruder.  You may be able to back it out by hand or you may need to reverse the extruder.
  3. If you are having trouble removing the filament, increase the temperature to 180c and try again.
  4. Clean the extruder gear and blow out any particles from the extruder entrance.
  5. Increase the heat and load the new filament normally.
  6. Run the new color through the extruder until it runs clean and the new color is all that is coming out of the extruder. If you are switching from a dark color (such as black) to a light color (like white or natural) you may want to extrude for a few minutes to be you sure don’t have any dark contamination.
  7. Print something that you don’t care if it has bits of the previous color in it, or run the extruder for several minutes.  It may take as much as 10 to 15 minutes of extrusion before you can have confidence that there won’t be dark material mixed with lighter material.

Note: We recommended removing the filament when soft rather than when fully melted so that there is a lower possibility of depositing melted material onto the extruder drive gear or leaving meterial high up the melt chamber entrance.  Both of which can cause jamming and are hard to clean out.  Soft removal also helps ensure that you get everything out of the extruder tip.

What to do when things go wrong

There are a few key things to check when your prints aren’t working.  But before we look at solutions we need to have a brief description of your symptoms.

“I can’t get the first layer to stick.”

  1. Make sure the extruder is at the right height. Adjust the limit switch or extruder to 0 height
  2. Make sure the print bed is level. Level the bed.
  3. Make sure you’re printing at the right temperature and that your bed is the right temperature.
  4. Check the ambient temperature of your environment. If it’s too cold or too hot outside, your print can vary drastically!

“The part has bad internal layers and top surfaces.”

  1. Check the extrusion temperature (you may need to increase it by 5 degree bumps).
  2. Check the filament tension.
  3. Clean the filament drive gear.
  4. Decrease your speed.
  5. Make sure your part is properly cooled.

“The outside edges of my parts have lots of little bumps on them.”

  1. Make sure your printer is getting enough data. If printing from a computer, ensure that the computer is not too busy to feed the printer commands. If the printer is pausing it is usually due to the printer being too busy.
  2. Print from the SD card. On some printers you can try and print from the SD card.  This often helps the printer have enough data to run more smoothly.

However, don’t be too quick to assume the problem is in your ABS.  With the right settings and patience hobbyists have succeeded in printing all sorts of materials many of which have very low viscosity.  You should be able to get usable parts even with some lower quality filament.

“Tall sections of my prints look melted or squished together.”

  1. Turn on “Cooling”. If your printer has a fan you should enable “Cooling” in the print settings.
  2. Get a small fan. If your printer does not have an integrated fan you should look into getting a small desk fan. This can help dramatically with tall sections of your print or when “bridging” (printing top layers that span gaps).

My part is curling off the bed.”

  1. Make sure that you have a good amount of adhesive on the bed and that you’re applying a fresh layer with every print. In addition, turn on a brim. Having a brim that extends out a bit helps give the part a large base to work with, as well as having more to adhere to.

“My printer will not extrude any material.”

  1. Make sure your hot end is getting hot. Check to make sure the hot end is heating at all.  If it is not, you need to have your printer serviced. It is likely that you have a loose connection, or your electronics have been fried (assuming the printer is still connected and responding to your host software).
  2. Clean the drive gear and adjust tension. The first thing we are going to do is clean the filament touching drive gear and ensure that we have proper tension against the filament.  Usually improper tension or a clogged drive gear will make the print look more like the picture we have for low temperature filament, but it sometimes does prevent extrusion all together.  Clean the pinch wheel with a wire brush, and make sure your tension is good and solid (too much can also prevent extrusion and is more common with direct drives [the motor is directly connected to the drive gear] but less common with geared drives).
  3. Remove the current filament. It may be that you have a small particle in your extruder tip jamming the plastic.  Use the change filament technique described above to pull out any particles that are in the extruder tip.
  4. Check for and remove jams between the extruder and hot end. This is the most extreme type of problem because now it’s time to take things apart.  Sometimes heat can creep up the filament in the extruder and cause a bulge that then cools and prevents any further extrusion. This is usually at the junction between the extruder and hot end. Take off the extruder and remove all the ABS you can (you may need the hot end hot to get all the material out.)  If you can’t get out all the filament by pulling, you may need to try and drive it down through the hot end. We usually use a small allen wrench.  If this fails you can try and drill out the extruder or hot end but you may need to replace parts.  Be sure to take precautions against being shocked or burned.  If you are not qualified to do this work, find someone who is, rather than risk injury.

Thank you for reading this article!

If you have any comments, corrections, or contributions, please drop us an email or give us a call. We are always looking for tips, and best practices – and would love to hear from you.

Sincerely,

The MatterHackers Crew