December 8, 2019
Description
#Welcome to the 3DLS Lead Screw Drive
#Aluminum Frame 3D Printer
#by Morninglion Industries!
#As seen on HACKADAY.com
You can find us on Discord! For tips, help and 3DLS specific stuff!
Here's a 4k render of the machine
#This is fully operational
#and printing now!
I have been rebuilding it with all the latest design parts and taking lots of pictures. Here's a gallery of all the pictures.
Video of it at 120mm/sec printing the back for my Rugged Raspberry Pi Tablet
Here's another Video printing at 150mm/sec outrunning my extruder the print didn't turn out well because the extruder could not keep up at these speeds. Follow up here and the timelapse of the failed print is here.
#Current Status:
#Test print done, all per this build!
Here's the time lapse of the 3D Benchy print
#Then I strapped it up by one side...
#I am writing the instructions now!
Here's some pictures and links:
It's now at 300 Accel X and Y with 100mm/sec top speed. There's still some over extrusion in the corners and some following of the infill. I am going to set infill/edge overlap to 0.
A video of it running for noise levels
The frame is based on Pheneeny's great AM8
The extrusions used are the same as theirs but that's it.
#Everything except the frame is my design.
You can retrofit most of this back onto an AM8 bit by bit however there's a lot of tweaks here.
#Specs:
#Goals:
#The Things That This Is Inspired From:
In no particular order either....
These have been used as is or modified and assembled here into a standalone Cartesian 3D Printer with No Belts!
#Full BOM:
Items that are direct links are the parts the machine is designed to fit.
#BOM for AM8 Conversion:
With the conversion you use the A8 Y carriage so do not print the Ender3 bed carriage.
#Firmware
I forked Marlin FW on Github, the latest firmware built and setup for the 3DLS is available on my Github page
#Why the SKR 1.4 Turbo?
It's all about speed with lead screws. The speed a stepper can run at on a controller is proportional to the CPU speed. The CPU is what generates the pulses required to run the motor.
As an example a RAMPS with Arduino MEGA 2560 runs at 16 MHZ. This limits the step generation to about 10MHZ before the CPU gets bogged down and begins to miss steps, this is with a single stepper too, divide that across 4 and you can quickly run into issues. This is with Marlin FW.
Now on a board with a faster CPU like a SKR 1.4 Turbo at 120MHZ can run the steppers up to 100MHZ pretty easily. This means a much higher top speed without bogging the CPU down and causing issues. Also the 32bit board has much more RAM for running Marlin effectively.
Now there's still other considerations for speed and this machine will never be quiet. It's not meant to be fast or silent though you are trading those in for a much more precise control and quality in the print. As it sits I am limiting speeds to 100mm/sec at quad stepping in X and Y. Since the screw has to turn 4x faster for the same speed compared to the belt this runs it at the same steps per mm as the belt since it's 1/4th less steps.
This has no real effect on accuracy. It's all about elimination lash and the rubber band effect all belts have. I have run a tolerance test at 60mm/sec print speed with this machine and got .2mm pass on it. On my highly tuned Anet A8 I ran the same test at 40mm/sec and got .3mm.
There's more info on the SKR 1.4 Turbo here and this page has lots of information on stepper driving and speeds here.
#Note on Closed Loops
I was using the BIQU ones, but I always had some issues. I recently got some MKS ones that work so much better. They are quieter, smoother and a ton faster! I can't recommend them enough.
#Assembly!
First cut the extrusions or you can find pre-cut kits for the AM8 on Ebay. You need 340mm long x2, 313mm x 3 and 440mm x 2. the ends of the 440mm sections should be tapped to M5, the holes are already sized and I like to use a tap drill for this.For now you can get the AM8 build guide or reference my renders and photos. I am still working ona proper guide.
Use the 3D printed frame corners to assemble the printer loosely first. just barely hand snug the bolts. The If you use the T-nuts you can pre-load the part and put the nuts in the channel then tighten.
Secure the corners with metal corner brackets on the insides. Tighten snug all the bolts on the printed pieces. Fully assemble the frame at this point.
For the Y axis mount the motor then coupler and bearing. Cap the bearing then slide the 8mm lead screw through the bearing into the joint on the motor and tighten. Install the Y axis nut in the holder and gently work it down the Y axis lead screw a good 100mm. Install a Collar Spacer and lock collar on the other end of the rod and slide the bearing holder on next. Keep this collar loose for now.
Mount the bearing in the Z motor mount.
Install the Z motor mounts on the frame loosely.
Insert the Z smooth rod into the motor mount.
Set the height by aligning the top of the Z rod with the top of the frame, tighten the motor mount at this position.
Mount the flex coupler to the Z motors and the lead screw to the coupler.
Mount the motor and Z lead screw in the motor mounts.
Setup the X axis. Install the LM8UU bearings in the holders and mount the lead screw nuts on both. Install the lead screw bearings and cap. Mount the motor then install the motor coupler. Slide the lead screw in through a collar spacer and lock collar. Push the rod firmly into the coupler and slide the lock collar up to the spacer and bearing and tighten then tighten the coupler.
Install the X axis nut on the carriage part and then on the lead screw.
Setup install the left side first by easing it down the Z lead screw. Then install the right side mounting the X lead screw in the bearing and working it down the right Z lead screw.
Mount the bearings in the Z upper caps and secure with the covers. Install the upper Z mounts sliding the lead screw into the upper bearing. Loosely attach the upper mounts to the frame then slide the smooth rod down through the top then the X carriages and finally into the lower mounts.
#Wiring
It's best to start by mounting the SKR, voltage converters, wiring block, MOSFETs board, RPi, and any meters you choose to include.
Start at the power supply. Wire 24v from the power supply to each voltage converter.
Run 5v to the RPi
Run 12v to the MOSFET board input. From there go to your lights, accessories and the relay for main power.
Negative from the power supply goes right to the SKR. The positive goes to the large relay and out to the SKR from the NO terminal.
Endtops, motors and others simply follow their directions.
#Assembled Pictures:
#Why the closed loop control?
Simply, it works. These are self contained microcontrollers monitoring the degrees of movement on the output so they always move the amount called for.
With TMC2208, 2209 or 2130 the machine skipped steps at high speeds over about 60mm/sec. It did the same with DRV8829 and LV8729 too.
For the money the performance of these closed loop controllers and the larger motors makes a huge difference.
#Firmware Notes!
I use Marlin 2.0.3 on a SKR 1.4 board. This is a 32bit board. I also use LV8729 drivers for maximum reliability at the high stepping speeds required.
To use these you want the jumpers on the SKR for Z and E you want #3 closed and the rest removed, This sets E and Z to 1/16th steps.
Set driver current voltages to 0.95V on X and Y and 0.75v on E and Z.
Now for the longer travel in the Y axis you will need to setup your home offsets and positions. Use these instructions to set home offsets. What I do is send command G0 X0 Y0 and adjust these offsets until the nozzle is over the corner of the bed. Make you adjustment and send the command again, save with M500.
In the firmware archive there's a Firmware folder with the files you need to copy into your Marlin folder then adjust and compile. It's set to SKR1.3 board with LV8729 by default.
If you wanna help me make these builds and others, as well as the sweet renders and buying machine parts, consider a donation! Maybe I will save them up towards replacing my 8 year old computer. You can always contact me a via a PM as well.
#Thank you!
Update 2/14/2020 Updated the Y axis rod holders to be a little stronger around the screws and fixed the upper right corner bracket hole positions.
Update 2/22/2020 Updated the X motor mount to correct some clearances for the endstop switch. Files updated. Instructions Updated!
Update 5/1/2020 Reloaded the firmware with Marlin 2.0.5.3 and new speed tweaks.
Update 5/5/2020 I ran into a spool that didn't fit on the spool holder so I designed a part that slides over the spool spike to hold a spool with as small as 40mm center and 100mm wide.
Update 10/7/2020 Available here to download. Moving away from Thingiverse.
Update 4/29/2021 Added the heavy duty Y axis motor mount i made for the CR-10 S5.
Update 4/30/2021 Reuploaded all archives. I fixed a missing part in the LCD case, updated the firmware to Marlin with the Bondtech E3D DD and added that hotend's files too.
License:
Creative Commons - Attribution - Non-Commercial
morganlowe
