Max, The micropellets are really interesting! At only 0.4 mm size, these could fit into a small lightweight screw that might be a better fit for the scale of a RepRap machine. I wonder if a 3 - 5 mm dia screw can generate 500 Bar at these flow rates? Here is pulverized ABS approx 0.25 mm particle size. SLS printers use Nylon powder. Here is PA12 at 0.06 mm particle size. It seems itby CinciCliff - General New Machines Topics
One very surprising discovery from our extrusion force testing data is the very high pressure generated when pushing against a 2.0 mm dia piston! At our target filament feed rate of 66.5 mm/s, our testing indicated approximately 34 lb of force is required to push fully molten 1.75 mm ABS filament through a 0.4 mm nozzle using a 2 mm piston. The corresponding extrusion pressure is approximatelyby CinciCliff - General New Machines Topics
Max, I am also very curious what clever solution BigRep cooked up for metering. I have experience with gear pumps like the Zenith BB PEP for metering hot melt adhesive, however as you mention these pumps are made out of big chunks of steel and very heavy. Micro gear pumps with tiny gears are used for room temperature metering of chemicals for medical applications, ink, and microfluidic systemsby CinciCliff - General New Machines Topics
Max, Congratulations! This is fantastic! It is great to see you recognized for your great work! Cliffby CinciCliff - General New Machines Topics
Max, Thanks for sharing! This is a fantastic build! Great engineering and fabrication! I hope you do well with the competition! Please let us know how you do? What integrated servo drive are you using for the Y? Cliffby CinciCliff - General New Machines Topics
@NitroFreak Thanks I really appreciate you sharing these links and your suggestion! Wow - the MXT technology from BigRep looks like a breakthrough to not just for extrusion speed but also precise control of the filament. It appears what they are doing is to feed the filament into a melting reservoir, then a separate servo driven metering pump (presumably a gear pump) . I found this explanaby CinciCliff - General New Machines Topics
@the_digital_dentist Thanks for another thought provoking post! Our long term vision for this printer is to print large parts primarily from ABS and other engineering thermoplastics such as Nylon 12, Polycarbonate, ASA, and maybe even high temp materials like Ultem and PEEK. Most of our team members have managed to print useful non-Yoda head items on our small printers at home from PLA - soby CinciCliff - General New Machines Topics
Here are a couple of videos to accompany our latest post. This video is Vesuvius (custom 80 mm long hot end) with Bondtech extruder running 1.75 mm ABS filament through a 0.4 mm nozzle at 26 mm/sec filament feed rate. We could not run faster without the extruder stripping / slipping on the filament. This video is the Linear Motion Test stand to measure Linear Extrusion Force vs Filament Vby CinciCliff - General New Machines Topics
@the_digital_dentist Thanks - we have been having fun running some experiments with high flow extrusion. You ask a great question about how to avoid creating a bowl of spaghetti or warm gummy worms. Our base plan is to use a second extruder with soluble support material to help stabilize voids between the warm extruded plastic. We also would like to explore building inside a heated temperaby CinciCliff - General New Machines Topics
We used a high speed / high force linear motion test stand to measure the extrusion force required to extrude fully molten plastic at various filament feed rates. The Vesuvius extended hot end was fitted with a precision 2.02 mm bore and a matched 2.00 mm piston pin. The piston pin was attached by a load cell to the linear motion sled. An 80 mm length of 1.75 mm filament was manually loaded iby CinciCliff - General New Machines Topics
Our Team has continued to focus on understanding the challenge of high flow rate extrusion. We continued testing to understand flow rate capacity of the Vesuvius extended length and Volcano hot ends driven by E3D Titan and Bondtech QR extruders. - Summary of test results is listed below. Our highest 1.75 mm ABS filament feed rate of 26.0 mm/s through a 0.4 mm nozzle was achieved with tby CinciCliff - General New Machines Topics
@ the_digital_dentist Cool - Thanks for sharing that the E3D SuperVolcano is out! Sanjay showed us this at MRRF and it looks like a great idea! We will order one to test. This looks like a really nice design! I appreciate the one piece nozzle. Our prototype uses standard V6 nozzle mated up to an M6 threaded rod sleeve. We added a screwdriver slot at the end of our sleeve - but this hasby CinciCliff - General New Machines Topics
@NitroFreak Thanks for your interest. Our Team has continued to focus on understanding the challenge of high flow rate extrusion. Our latest force vs flow rate test results are encouraging. We need to summarize our test data and will post an update soon.by CinciCliff - General New Machines Topics
Great point on leakage - we wouldn't our nice printed parts to float away in a coolant leak tsunami! Thanks for the tip on the air cooling hoses used on the older Statasys printers! Good to know this is proven technology - our newer printers at work do not have these cooling hoses. For anyone curious I found these great pictures from a teardown of an FDM 2000:by CinciCliff - General New Machines Topics
@piper3d Great question - we have not measured what is contributing to the back pressure and friction of forcing the filament into the extruder at high speeds. I was assuming that most of the pressure drop would be due to the flow restriction through the nozzle. A 0.4 mm nozzle has 1/25 the cross-sectional area vs the 2.0 mm filament supply hole. The average velocity through the nozzle wouldby CinciCliff - General New Machines Topics
@ the_digital_dentist That is a fantastic use for a C-Pap blower - awesome! Thanks for taking the time to write your great Tech Topic blogs! For our heated build enclosure ABS printer, I am thinking about using a localized closed loop air cooling system for the motors, extruder, ball nuts, etc. That would be a great blower to help keep things cool and maybe less complexity than water cooliby CinciCliff - General New Machines Topics
@piper3D Good question - we are not sure if the added length is adding more friction? We plan to do more testing to understand this better. I am borrowing an IR thermal camera to allow us to better evaluate the temperature of the extruded filament. We will also measure the power consumption for the heater. At MRRF we saw a cool extruder from Bondtech that uses dual drive gears - a hob on bby CinciCliff - General New Machines Topics
The Midwest RepRap Festival MRRF 2018 was an incredible experience! We enjoyed making new friends and learned so much from talking to fellow 3D printing enthusiasts! We were overwhelmed by the number of cool printer builds, brilliant examples of printed parts, and hardware from event sponsors that we are excited to experiment with. Thanks to everyone who talked with us about our high speed priby CinciCliff - General New Machines Topics
@dc42 Thanks for sharing the Exploration of print speeds with a Diamond hot end! This is a great write up and video that we had not found yet. It was encouraging to see printing at 260 mm/s - especially given this was with Bowden extruders. Has anyone seen similar tests with a direct drive extruder? Thanks for letting me know about the nonlinear extrusion capability in Marlin. This soby CinciCliff - General New Machines Topics
@the_digital_dentist Son of MegaMax is an awesome build - I really appreciate your sharing your experience! Is SoM going to be at MRRF this weekend? I totally agree that we will have some work to do to stiffen up the extruder / hot end and insure it is compatible with the heated enclosure. Our crazy 80 mm long hot end is only intended for some bench flow testing. Not only would the heat breaby CinciCliff - General New Machines Topics
2018 Midwest RepRap Festival Our team is looking forward to visiting the Midwest RepRap Festival March 23-25, 2018 in Goshen Indiana, USA. We will bring some of our early components to share. We look forward to some great discussions and enjoying some beverages with fellow 3D printing enthusiasts.by CinciCliff - General New Machines Topics
Vesuvius – Extended 80 mm Hot End Experiment The E3D v6 Volcano hot end has a 20 mm heating length which is a good improvement over the 12 mm in the standard V6. Our hypothesis is that volumetric throughput is limited by heat transfer to the filament and that a longer heating length can provide better heat transfer and high flow rate. To test the flow rate improvements possible with an extendeby CinciCliff - General New Machines Topics
Flow Rate Testing of E3D V6 Volcano Hot End with Titan Extruder Initial testing is to determine if standard E3D V6 Volcano Hot End and Titan Extruder can achieve adequate flow rate for printing at 1,000 mm/s. Target flowrate for 1,000 mm/s printing is 576 cm^3/hr. Normal expected flow rate is 288 cm^3/hr based on 0.2 mm layer height with 0.4 mm nozzle. This would require filament feed rateby CinciCliff - General New Machines Topics
Why Heated Build Volume? At work we have a Stratasys FORTUS 450mc (16 X 14 X 16 inch) and Dimension SST 1200es (10 X 10 X 12 inch) which each employ a heated build volume (printing inside of an oven). These are fantastic workhorse machines. Printing ABS or ASA using soluble support structure (from a second extruder), we can get some very nice accurate parts that are free of warping. A flat suby CinciCliff - General New Machines Topics
Why We Want to Explore High Print Velocity and High Dynamic Performance It would be useful to print large parts such as custom automotive parts, full size Halloween costumes, toys, sculptures, etc achieving an attractive surface finish and fine detail. We initially were planning to build a large format printer with comparable performance with our PRUSA i3 MK2S and TAZ 5 printers. We approxby CinciCliff - General New Machines Topics
The Millennium Peregrine is a high speed large format development project intended to understand the process performance limits of Fused Filament Fabrication (FFF) 3D printers and to create a new machine capable of printing large high resolution objects in a reasonable amount of time. This project is just beginning – preliminary calculations look promising, we have started some preliminary tesby CinciCliff - General New Machines Topics