Chiron Hemera Update Guide incl. Linear Rail

thingiverse

After getting my 2nd hand Chiron I needed a new mount for the Hemera. I used the <a href="https://www.thingiverse.com/thing:4297095">Anycubic Chiron Hemera Mount</a> from <a href="https://www.thingiverse.com/tmaxx21/designs"> Tmaxx21</a> and was not disappointed. Later on, I decided to do a comprehensive upgrade of the Chiron and to remix the mount to fit a linear rail. I did not find any guide for a Chiron update, so I decided to write this post. As this is my first Thingiverse content feedback is welcome. <h1>What was done:</h1> - Changed stepper drivers to TMC 2208 - Changed to Knutwurst firmware - Extruder was already changed to Hemera direct drive - Added new fan duct for part cooling - Changed heating bed to linear rail - Changed hotend to linear rail <h1>Update drivers to TMC2208</h1> I have replaced the default stepper drivers with TMC2208 drivers. Mainly because they are quieter but also capable of UART (if needed in the future). I took the <a href="https://www.amazon.de/BIQU-DIRECT-Printer-TMC2208-Heatsink/dp/B07RN4WX7G/ref=cm_cr_arp_d_product_top?ie=UTF8">BIQU TCM2208 </a> because I already used them in my Mega S and they have been doing very well for the last year. It is not that difficult to change the drivers and several tutorials can be found on Youtube. If you do not want to change the pins of the stepper motors, have a look at the Knutwurst chapter. After changing the stepper driver, I set all Vref to 1.1V. At least the heatbed had step losses at <1.1V when using linear rails. No problems have occurred since increasing voltage. <h1>Change to Knutwurst</h1> Why update to Knutwurst firmware? The main reason was the change of the stepper drivers. Using the TCM2208, the direction of the stepper motors changed and I did not want to fix this by rearranging the cable pins. For Knutwurst a special TCM version is available which changes the direction of the stepper motors using the firmware. Other advantages of Knurwurst are... - Thermal runaway shutdown - PID tuning hotend and heatbed - Easy 4-point bed levelling - Mesh bed levelling (which you do not need for the Chiron) - and many others There is a really good <a href="https://github.com/knutwurst/Marlin-2-0-x-Anycubic-i3-MEGA-S/wiki/Beginner's-Guide-(English)">beginner's_guide</a> how to identify the correct version for your system and to install the firmware. <h1>Change to Hemera direct drive</h1> There is not much to say about this upgrade, but this linear rail mount is actually for a E3D Hemera hotend only. You will find the extruder following this <a href="https://e3d-online.com/products/e3d-hemera-direct-kit-1-75mm">link</a> to the E3D Hemera 24V. Use it and have fun. To cool the hotend I used a <a href="https://www.amazon.de/L%C3%BCfter-40x40x20mm-21dBA-Sunon-EB40202S2-999/dp/B00MNJD8BE">Sunon Maglev 40x40x20 fan</a>. Fan mount was used from <a href="https://www.thingiverse.com/thing:4297095">Anycubic Chiron Hemera Mount</a>, which also includes a mount for the levelling probe. For the fan grill just choose one of the 40mm grills from <a href="https://www.thingiverse.com/thing:2802474">Customizable Fan Grill Cover</a>. For mounting the fan, you need: 4x M3 x 30mm hex screws 4x M3 spacer 2x M3 nuts Mounting of the Hemera direct drive will be described in the chapter of updating to linear rail. <h1>New fan duct for part cooling</h1> Changing to the Hemera extruder also requires a change of the fan duct. I have tested several versions and got the best results using the design of <a href="https://www.thingiverse.com/hangtight/design">James Tongue</a> (Link to <a href="https://www.thingiverse.com/thing:4042492">Hemera part cooler</a>) For mounting the fan duct for part cooling you need: 2x M3 x 8mm hex screws 2x M3 spacer 2x M4 x 25mm hex screws 2x M4 spacer 2x M4 nuts <h1>Changed heating bed to linear rail</h1> There are several guides for changing the heating bed to linear rail on Thingiverse. I decided to do it the lazy way. Instead of using the small MGN12H I ordered some <a href="https://de.aliexpress.com/item/4000261882276.html?gatewayAdapt=glo2deu&spm=a2g0o.order_list.0.0.21ef5c5fyXShq8">HGH15CA blocks and 600mm rails</a> at AliExpress. The big advantage? They are fitting the base plate of the heating bed and there is no need to print any parts. <h1>Changed hotend to linear rail</h1> But the biggest improvement was, to change the X axis to linear rail. Due to the weight, I used <a href="https://www.amazon.de/gp/product/B078M1FRJQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1">MGN12H blocks and 550mm rails</a> at this point. As I did not find any prints on Thingiverse fitting my needs, I remixed the mount I used with the original backplate. I split the mount into 3 parts for easier printing. - Hemera base plate - Belt mount incl. 2x clips - 2x 20mm cable chain mount Additionally, you need: 2x brass threaded inserts M3 x 5.7 x 5mm 4x M3 x 8mm 6x M3 x 10mm 2x M2 x 12mm 2x M2 nuts 2x M3 nuts or 2x brass threaded inserts M3 x 5 x 5mm 2x M3 x 14mm or 2x M3 x 12mm 1x 20mm cable chain (printed or buy this <a href="https://www.amazon.de/Befenybay-Schleppkettenkabel-Drahttr%C3%A4ger-CNC-Maschinen-10mmX20mm-Au%C3%9Fen/dp/B07SFFT1K5/ref=sr_1_5?keywords=schleppkette+10x20&qid=1648828651&sr=8-5">10 x 20mm cable chain</a> 1x <a href="https://www.amazon.de/gp/product/B07JGXG7S2/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1">5m GT2 belt</a> Assembling: 1. Put the brass inserts into the Hemera Base Plate, right below the notch for the linear rail block. 2. Use 4x M3 x 8mm to screw the MGN12H block to the Hemera base plate. 3. Use 2x M2 x12mm and 2x M2 nuts to screw the endstop switch to the Hemera base Plate 4. Use 4x M3 x 10mm to mount the base plate on the Hemera direct drive 5. Slide the hotend PCB into the Hemera base plate (no screws needed) 6. Connect endstop switch, hotend fan, thermistor and heating cartridge to the PCB 7. Install the belt mount using the 2 belt clips. Attention: you may need to replace the belt and use a longer one! 8. Carefully slide the linear rail block onto the rail and use 2x M3 x 10mm to screw the belt mount onto the base plate 9. Install the endstop and the part cooler 10. Use 2x M3 x 14mm and M3 nuts or 2x M3 x 10mm and brass inserts to screw the cable chain mount to the base plate. Install and connect all cables to the extruder and PCB You are ready to go. <h1>Some final words</h1> This project is still in development and I will do my best to include feedback. So, if there are any changes to improve usability or stability, please let me know. For those, who want to remix parts by their selves, I added the Fusion 360 files to the download. Have fun with your Chiron!