Close
Login to Your Account
Results 1 to 1 of 1
  1. #1
    Join Date
    Jan 2020
    Location
    Posts
    1
    Downloads
    0
    Uploads
    0

    COMPOSITE FDM PRINTING - Printing with Fibre Reinforcements

    Hello to all out there in the 3DP sharing world,

    Introduction

    I am writing to the community in order to launch an idea I am most excited about, freely and without restriction in order to lever creative open sourced resources to make it develop fast. If this idea can spark others that would like to invest, go for it (just remember me ;-). If this idea already exists and is developed and works, please advise.

    3DP is now at the heart of my activities, it be as an invaluable development tool professional as an industrial designer, and my favorite toy as an inventor-tinkerer-explorer-maker. As a passionate sailor in all four season, many of my projets are wind related, whether it be boats, kites, foils or wind power. I have a great interest in permanent magnet motors and battery technologies for which I use it extensively. I am most excited about the advent of GRAPHENE. Apart from super-conductor batteries for our electric cars, I just can't wait to 3D print plates and tubular structures on a nano level.

    BPPN (BIG PICTURE Personal Note): My we live in excitingly disruptive and explosively fast times! I see this onset of human sharing and pooling of knowledge as hope for a new way of life, one that might just allow us to find novel solutions that may allow our species to survive mass extinction and help us migrate to a more sustainable, equitable World. Apart from the darkening skies, air that triggers my asthma, concerns about my water, depleting oceans and nations ablaze, I find it is an exciting epoch to be alive. You?(End of my philosophical monologue hehehe)

    I stumbled upon this process out for my interest and long experience with COMPOSITE materials. I a recent hydrofoil project, I have been 3D printing cores for complex and articulated hydrofoil sections. I encapsulate these with various skin fibres, 0-90 degree, 45-45 or unidirectional, depending of course on the desired properties we need. Even regular PLA is quite suitable for such cores, since most sandwich constructions use honeycomb and foams that only need to be there to perform dimensional spacing of skin and provide low level shear. But 3DP is so much more powerful than expanded polystyrene beads, we can orient our reinforcements for particular tasks, we can literally design on a microstructure level. I find that regular grid infill does the job and prints fast, but gyroids and other minimal surface structures are also to be be explored.

    Note: FIBRE REINFORCEMENT of DFM only increases strength and rigidity in the XY plane. Though we can increase properties five fold in this plane, we are still stuck with adhesion in the Z build direction. Vacuum encapsulation with composite skins covers this of course. The only concern we may have is in the Z vector.

    Extreme Examples where it could works at it's best
    • Hydrofoil for high speed sailing above the water with sails, wings and kites
    • Ultralight wing sections for aircraft, model scale and full scale
    • Reinforced concrete (3DP cement with glass or natural fibre strands)
    • High performance spars, shafts and ultra lightweight panels


    Description of the Process

    A client of mine has a MARKED FORGED machine which I use often. This brilliant machine prints special filaments with continuous fibre, generally carbon, but most likely others as well. I have been much inspired by this quality build machine, I looked tat the special pre-extruded filament that has a diameter very close to that of the nozzle. I now understand why it is that way ;-) BRAVO and hats off to the MARKED FORGED TEAM. This industrial designer gives you 5*/5.

    My needs and where I would like to take this is somewhat different. I would like to print very large parts. In fact, I have two machines already on the drawing board; one that 3D prints very large plat panel cores (comes out a project to 3D print DML loudspeakers with the core designed for specific and advantageous resonances for accurate music reproduction) and another to print normal table sizes but a ridiculously tall Z build dimension. You see, when you want to print parts that have a one layer skin an minimal infill, we can make very large parts.

    In terms of the post printing secondary processes to complete the desired parts, panels, hydrofoils or lightweight airfoil wings, fuselages and such, we basically vacuum encapsulate our reinforcing fibres with epoxy. Because of the build texture, we get good mechanical bonding and vacuum encapsulation pushes excess resin into the core skin which somewhat porous and infill boundary to further solidify the entire structure. Personally, I like to use clear PLA filaments with glass and clear epoxy resin to see the beauty and the stuff within (tubes, rods, electronics, sensors, strain gauges, mechanisms, LED lights...). The possibilities for a designer are ENDLESS with these materials and processes.

    Experiments so Far and Challenges

    So far, I have been printing with KEVLAR fibre. KEVLAR is a very high temperature polymer that is also very flexible, abrasion resistant and unbelievably tenacious. I use sewing thread sold for making firefighter equipment that is readily available in various weights out of China. What I have purchased is generally double strand and spun like any other thread. I 3D printed a "unspinner" to recoil the loose strands on small lightweight spools that I can pop right on my printer head, much like a the sewing bobbin under the needle. These loose strands feed into the extruder. I first simply drilled two holes in the Bowden tube just above the head. I also modified tube connectors to feed the fibre deeper in the head where the filament is molten.

    There area number of challenges however:
    • Mixing the thread intimately with the resin matrix of the filament. Un-spinning the thread into loose fibres fed in clusters was the
    • key and I have great dispersion now.
    • Turning corners before the filament sets, the thread would pull out and not feed. This also was fixed by unspinning the thread and using loose fibres
    • Rapid moves require pulling a lot of fibre through the molten filament, which cools it, so there can be great resistance. IMHO, he solution is to completely disable use of rapid moves and always extrude continuous fibres. This will involve custom codes in SLIC3R, CURA or perhaps even special software that we will need. I thought of snipping the fibre but KEVLAR being what it is....


    Many other fibres can be considered, each with their particularities. Some may require special nozzles in order to be deployed around that right angle turn!

    Conclusions

    In a nutshell, that is where we are at. I am at the end of my carrer and I have embrace the sharing economy. It is the time for others that I would like to inspire to com on board. So, this said, this new OPEN PROJECT on the table for all to witness, to see, evaluate and to contribute to. And there are many others ideas on the way, some so wacky you have no idea.

    I can supply everything I have to get this going; images, tests results, 3D CAD files, samples,... it's all ours ;-)
    So let's get to work !

    Kind regards,

    Paul
    Quebec City, Canada.
    Last edited by Paul Isabelle; 01-05-2020 at 01:15 PM. Reason: New ideas to add and share...


Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Wanted Source for Carbon Fibre Reinforced PEEK Filament?
    By Robert Zammit in forum 3D Media and Filaments
    Replies: 1
    Last Post: 01-04-2017, 07:29 AM
  2. News Father of 3D Printing Tells CNN of the Night he Invented 3D Printing
    By 3DPFadmin in forum Manufacturer News & Announcements
    Replies: 1
    Last Post: 02-14-2014, 09:55 AM
  3. DISCUSSION Skyforge, 3D Printing vending machine - Redbox of 3D Printing
    By Marc in forum Club House
    Replies: 0
    Last Post: 02-05-2014, 11:45 AM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •