The Build Continues

I guess it's been a while since I posted an update. The project is moving along rapidly in the right direction. Materials have been arriving to facilitate the build phase.

The Z axis design is almost locked down. I have started machining the aluminum components for it already. I picked up two Newport fine adjust screws for leveling the bed. They have 100tpi rolled threads and work great. I also found some oversized THK rails for the Z axis. I picked up a 12mm ACME screw and brass nut for the Z axis drive. I will need to get the end machined and figure out a way to attach to the Z axis bracket.

The ALCA-5 plates for the top and bottom of the machine are here and will need machined, drilled, and tapped soon. Still a few more details to be sure everything lines up. Measure 4 times, cut 3 right?

I will finish machining the T-Slot aluminum framing tomorrow.

I've ordered the silicone heater mat for the heated bed. It will be 600W at 110V so it should heat the 300x300mm bed up fairly quickly.

Here are a list of outstanding design issues left:

• package the electronics: provide mounting locations and forced air cooling. evaluate over temperature sensor if forced cooling fails.
• threaded holes for limit switch flags and sensors
• Finalize belt clamping at the printing head
• belt tensioning device for each belt: will be used to calibrate X-Y orthogonality
• finalize Z leadscrew mounting and connection to Z axis bracket. Finalize Z motor mount and thrust bearing
• bracket to mount extruder
• pole to hold core of filament spool
• Z limit sensor

Up and Running CoreXY!

Big update today! The Filameister design is finally built in real life and seems to run very well!

All the parts have finally arrived, the machining is done, and the XY portion is all wired up. This is a temporary acrylic prototype to discover any loose ends before final design modifications and the real build in aluminum.

Tested so far:

• Duet3D Wifi - Huge fan of the hardware and the web interface!
• Linear bearings - we use these at work so I knew they would be great
• 0.9deg NEMA17 stepper motors for higher mechanical resolution
• Genuine Gates belts and pulleys.
• Optical end of travel switches. Specifically SUNX PM-F24.
• Fan ducts for hotend heatsink and part cooling
• PT100 sensor for the hotend.
• V6 hotend mount and heatsink ducting

Left:

• Design Z axis and heated bed
• Design electrical cabinet / wire routing
• Wiring for hotend, fans, sensors, LEDs (pcb?)
• Bracket for Bontech Extruder
• Filament Reel Mount
• Test polycarbonate fan ducts in close proximity to hotend for thermal issues (heat shield or insulation required?)
• Finalize Z stroke and source Z axis leadscrew and bearings
• Finalize enclosure size and panels
• Source aluminum components
• Build the final optimized printer design!

Here are some more various pictures of the progress:

CoreXY re-design

So I took the plunge and re-designed the XY axes to use the E3D style CoreXY design without the crossing belts. I like their design because it looks simple to build and stiff structurally.

Currently, I have the XY system basically designed around the components I have sourced. In other words, adapted to the linear bearing lengths, motor sizes, V6 hotend etc that I have already acquired.

I will be prototyping the XY motion this weekend hopefully if the rest of the shoulder bolts arrive in time! I am going to prototype the aluminum plate and crossbeam in acrylic because I can laser all the holes in the right spot with the cnc laser at work. If the prototype works, I will commit to making an aluminum version.

A view of the CoreXY belt system:

More Parts

Parts keep arriving from all over the world. I'm really excited to see the potential sitting on my bench!

- E3D V6 with titanium heat brake and solid copper heater block
- Bondtech bowden extruder
- Duet3D Duet 2 Wifi
- Gates GT3 2mm pitch belts and AL pulleys

Also, I have been seriously considering changing the design to follow the mechanics of the E3D motion system which is CoreXY based without the belts crossing. Since i do not have immediate plans for a tool changer system, this will limit the Filameister to a single material whereas originally I was designing for one and leaving room for a second on the same beam similar to the IDEX on BCN3D Sigma.

Here is my rough concept at the moment. To make this change, i will have to find a way to support the idler pulleys since E3D does not sell their custom made hardware (yet!). I will probably prototype in aluminum and maybe replace the beam with carbon fiber at some point for increased stiffness.

And, I got the X and Y axis motors to run back and forth which is always an exciting step in any build:

Linear Rails are here!

IKO linear rails for the gantry! still have to decide what rails to use for the Z axis.

First parts arrived from Sweden!!

Here is that Bondtech goodness!

now i just need to find a motor for this thing...

Gotta reduce that X axis mass

going to be running some deflection FEA to see if the linear rail alone will be stiff enough. currently, the entire X axis is about 1300 grams which is too much! the hotend assembly is only 230g.

deflection analysis shows abou 200um for 18N load on center. This is not acceptable. I will need to evaluate stiffening the 9mm rails or getting bigger rails.

It looks like added a square tube with thin cross-section is the way to go to stiffen this axis. Deflection at 4g acceleration was brought down to around 12um with much less weight than the original design. typical accelerations will likely be less than this.

The new Y axis moving mass is about 750 grams. I still need to run some more numbers to see if this will be light enough.