Hercules - QIDI X-Plus / I-Mate (S) Carriage for BMG & Dragon / E3D V6

prusaprinters

Update June 6, 2022BMG & Dragon / E3D V6 is now supported by Icarus 2, I recommend going with that instead as it's a better and future-proof platform to build from:Icarus 2SupportAll my designs and mods on Printables are free to use and remix. They have a non-commercial license. If you enjoy this or any of my other designs you can send me a small donation using the link below. Thanks :)https://www.paypal.me/humebeamengineeringUpdate August 19, 2021I've added a new file to print. It's a PTFE cutting jig so you can easily cut the exact length required for the hotend:hercules-ptfe-cutting-jig-1.0.stlIt's made for the Trianglelab BMG 2.0 in the BOM. If you're using another BMG clone or an original Bondtech BMG it's likely a different length that is required, however, I have included the step file so you can easily edit it.AboutHercules is a sturdy and dimensionally accurate one-piece carriage for the QIDI X-Plus and I-Mate (S) that was designed focusing on strength and ease of maintenance while keeping it lightweight. It uses self-securing cable management that doesn't require any cable ties. The PCB snaps in place and is moved to the side so it's not in the way of extruder access.Scroll down to the bottom of the page to see some test prints using Hercules with BMG and Dragon.The whole carriage is only roughly 100 g depending on infill and filament type used and the extruder and hotend are easily accessible without removing any other parts, although removing the blower fan attached with a single screw is recommended. Once the carriage is installed, there is no play between the bearings and the carriage.Hercules is using the popular dual gear BMG extruder and Dragon / Dragonfly or V6 hotend.It was originally a remix of cwills75's design which in turn is a remix from jhenrikb's carriage, who did the original. This is however, completely redesigned. I've kept the outer dimensions for the carriage and the mounting holes for the fan duct identical for cross-design compatibility. Thanks to jhenrikb and cwills75 and the other guys pioneering the work and for calculating e-steps and firmware settings.Why?Curiosity. I didn't find the original QIDI extruders as bad as some people did but had to find out if they could be improved. I also wanted to be able to print a wide range of filament without having to switch extruders or worry about unrecoverable QIDI high temp extruder clogs and gear slippage. Ease of maintenance is also a big plus.Is it better?With Hercules I'm using a Trianglelab BMG (Clone) extruder and Trianglelab Dragon hotend and it prints even better with cleaner lines and the dual gear extruder is night and day. Clogs are a thing from the past and no more grinded up filament stuck in the gear.Here's a comparison picture by Hercules user techguychad:What to print:Print these files:hercules-1.7.2.stlhercules-dial-holder-1.3.stlhercules-belt-peg-1.2.stlhercules-fan-duct-1.3.stlbmg-handle-short-1.0.stlhercules-ptfe-cutting-jig-1.0.stlOptionally, print the PCB cover and ribbon cable holder clip as well (not required):hercules-pcb-cover-1.1.stlhercules-ribbon-holder-clip-1.0BOM - Bill of MaterialsI buy most of my 3D printer parts from quality stores on AliExpress. Shipping takes a while from China but quality is excellent and the prices are good.  I might add more stores to the BOM later but it's a lot of work keeping it updated and current so I will try to keep it short.Hotend / ExtruderYou can use a genuine Bondtech BMG Extruder and E3D V6 hotend or a Trianglelab V6 clone if you like. The Dragon hotend is the best though. You can go with either Standard Flow or High Flow Dragon, I have both and they're both great although the Standard Flow is a bit easier to print with.Dragonfly HotendBoth BMS and BMO supported.AliExpressBMG ExtruderAliExpress6x20MM 24V 60W Heater CartridgeAliExpressT-K500 Thermocouple (3 x 15 mm)The budget version is fine. Buy a spare.AliExpressAliExpressSunon Maglev MF40202V2-1000U-A99I use this Sunon Maglev fan, it's rated at just 21 dB(A). 7.7 CFM.AliExpressFastenersYou need some M3 hex bolts (socket head) at various lengths. It's best to grab the kit below, it will have everything you need for this build and many more.Heated M3 inserts are required too, for example for attaching the fan duct to the carriage, you will find out more about this later in the build.440 pcs M3 Hex Socket Head Cap KitAliExpressM3 Heated Inserts2 x 10 pcs required.AliExpressToolsYou also need a JST crimping tool and some JST-XH terminals and connectors. I'm using this IWISS crimping tool which is inexpensive and is doing a good job. A digital dial indicator is optional but it's recommended so you can level the bed perfectly. A soldering iron is needed too for the heated inserts.IWS-2820M Crimping Tool + Terminals & ConnectorsSelect the option (IWS-2820 2.54 XH-F).AliExpressDigital Dial IndicatorAliExpressSoldering IronAliExpressOptional PartsThese parts are optional. You can use the extruder PCB, blower fan and stepper motor from one of your old Qidi printheads. The stepper motor in the list below is about 85 g lighter than stock. The other parts are spares that are good to have on hand except for the Energetic PEI sheet which is recommended.24V 5015 blower fanAliExpressTitan Stepper Motor 23 mmAliExpressPlated Copper T-V6 NozzleAliExpressHardened Steel T-V6 NozzleAliExpressPowder Coated PEISelect “Update one” option.AliExpressQidi extruder PCBAliExpressTrianglelab Filament PA-CF15AliExpressHow do I use the Dial Indicator Holder?You can achieve perfect bed level in about a minute without removing any parts / carriage.As the dial holder is in front of the carriage it doesn't measure on top of the bed leveling screws but it doesn't matter for accuracy, we still achieve perfect bed level. The script checks the bed level on three different spots on the bed in a triangular pattern. Adjust the bed leveling screw closest to where it measures and by the time the script has looped three times the bed will be perfectly level.Copy to your USB and just print it like you would a normal model (print the correct one):qidi-xmax-hercules-dial-bed-leveling-script-v2.gcodePrint SettingsPrint the carriage in high temp resistant filament. I recommend using Polycarbonate (PC), a PC blend such as PC-FR (flame retardant PC), PC-CF (PC with Carbon Fibre) or PA-CF (Nylon with Carbon Fibre).This PA-CF should be a great option:Trianglelab Filament PA-CF15To summarize, print the parts in PC if you can to be on the safe side.Print all parts in 0.2 mm layer height using a 0.4 mm nozzle. I recommend using 4 or 5 top, bottom and perimeter layers with an infill of 25% or higher.The whole carriage prints in one piece with supports only needed in a few spots:Above the arches over the rodsInside the fan ductInside the hole for the motorAbove the belt fastenerPrint the carriage with supports for angles above 52 degrees only and no supports will be placed below the carriage where the bearings hold it in place.The fan duct for parts cooling, the belt peg and the optional PCB cover all print without supports. The optional dial holder needs some supports but is easy to print.Notice: If for some reason you find the carriage sits too tight or too loose you can print one of the other carriages with narrower or wider clearance for the bearings. It also depends on slicer settings so make sure you dial in flow before you start.Precaution!Before you start, please ensure you use the parts in the BOM only. It's very important to use a high quality thermocouple that is rated for 500 C for example, the stock Qidi thermocouple is only rated at 300 C.If you want to increase the print temp beyond 300 C (stock) you can enable it in firmware, I have commented it there.Do the mod at your own risk. Never leave your printer unattended, stock or not.Assembly InstructionsSome pictures from the assembly guide below are from an earlier version of the carriage but the principle is the same for the assembly, the purple carriage is the current version. Just below is a picture of the assembled unit:But we start the guide from scratch. Install the gear that came with the BMG extruder on the stepper motor like pictured. I'm using a Trianglelab 23 mm stepper motor to save some weight (it's about 85 g lighter) but the stock Qidi extruder motor from one of your extruder setups is fine too. If you go with the TL 23 mm stepper, I would recommend using the supplied heatsink. The correct wire orientation for this motor is blue, red, green, black. There is a picture of this further down the guide.Insert 4 brass insert using a soldering tool to the bottom of the carriage. Press it slowly then once it's almost fully in, turn the carriage around so it's standing up and then press down the whole carriage for 10 seconds on a flat high temp resistant surface. The backside of the QIDI bed plate is perfect for example.Do the same for the extruder fan holes, the blower fan and for the dial holder. In total 8 brass inserts will be mounted.Install the extruder fan with the sticker facing the carriage using two 25 x M3 bolts. Shorten the wires and crimp on the connector. The PCB sits just above so it doesn't have to be very long. The connector should sit the same way as the original, take a look at the red and black wire and the connector. If you're using another fan the polarity may be reversed and if so you just have to unpin the wires and reconnect.Cut the thermocouple and heater cartridge wires to 20 cm. Pictured here is the 50W heater cartridge and an older TL thermocouple version but I recommend using the 60W heater instead (it's linked in the BOM), it heats up quicker and the cable is much better.Do not cut the cables shorter than this, you can keep them longer if you like but there's no need. Crimp on a JST-XH connector on the thermocouple. I used heat shrink tube on both thermocouple and heater cartridge but it's optional, it can be easier to get the pin header to grip by doing so. The thermocouple can be a bit difficult to work with so take it slow.Notice! If you get a temp drop when you start heating the printer for the first time you have probably reversed the thermocouple cables. If so just unpin the connector and switch over.Move over the gear and pin from the original BMG handle to the printed short handle. We do this else the handle might hit the top of the frame of the printer.If you want to use the original (tall) BMG handle you can edit your firmware file and reduce the build plate size and it will not hit the frame. So for example, edit xplus-imate-firmware.gcode with notepad and change the values to this:; Set XY distanceM8024 I270; XM8025 I192; YYou may need to adjust a little but this should be on the safe side. Save the firmware file, you will print it later.(This will of course reduce the build size by a bit. If you want to keep the full build size use the printed handle).Make sure you've received the correct type and length of the bolts for the extruder, the thread should be 40 mm long and they should be head cap like the bolts listed in the BOM.That way they fit in the holes of the extruder like picture and stick out about 4 mm so there's plenty of grip in the threads of the stepper motor while not being too long so they bottom out.Shorten the PTFE tube that came with the Dragon hotend using the PTFE cutting jig that you printed, that way the length will be exact. Then insert it so it sticks up like pictured.Assemble the extruder like pictured. You'll want the hotend at the bottom with the shortened PTFE tube sticking up into the white filament guide above. Then the large gear above it and the printed short handle on the side.Use the 20 mm M3 bolt, spring and washer to secure the printed handle. You fine tune the tension of the spring and thereby the gear pressure against the filament later but for now I find about 4-5 half turns of the screw is good. You can use the original thumb screw instead if you like.At this point you can also install the thermocouple and heater cartridge in the heater block, they're held by screws preassembled at the bottom of the block. Use the silicone sock over the heater block (optional).Place the assembled extruder/hotend on the right side of the carriage while guiding through the cables. I find it best to place the thermocouple on the bottom of the cable guide since it's thinner and follow with the heater cables above. Press down and they will sit firmly.Next route all three cables 90 degrees up towards the rear of the PCB plate and around the corner. Pull and the cables with sit firmly below it. No cable ties are needed anywhere. Do the same for the motor cable and blower fan cable. If you want you can shorten the motor cable and run it in front of the PCB instead.Fasten the extruder to the motor using the 3 x 40 mm bolts. Line up the heater block in the correct direction, the heater cartridge should be the closest to the motor/front and the thermocouple towards the blower fan.There should be plenty of space below the extruder for the cables to fit but you can use a screw driver to poke away the cables to ensure they're not in the way before tightening the bolts fully.Connect the rest of the cables. Make sure all connections are correct in the PCB:Top left slot is the extruder fan, next to it is the blower fan. Next to that is the thermocouple.On the next row we have the heater cables that screw into the green connector. And finally next to that the 4-pin motor cable.Tidy up cables if needed. Do a test mount of the dial holder and dial indicator if you like. Be sure to remove both holder and indicator before you actually print though as they will hit the frame and might break.The carriage is now assembled and can be installed in your printer.If you're using the Trianglelab 23 mm pancake stepper in the BOM, here is the correct cable orientation of the motor: Blue, red, green, black. If you're using the stock Qidi motor you don't have to change the wire orientation. Next, remove the original QIDI extruder and carriage. It is not pictured but to do so remove the screw from the top cover, remove the cover, unplug the ribbon cable, unscrew the extruder from below with the two screws (and possibly fan duct if you have one), lift out the extruder, remove two screws holding the belt plate, lift over belt then pull off the whole carriage carefully but firmly, it can sit very tight on.At this point it's time to install Hercules carriage into your printer. Line up the bearings below the carriage until you feel the location is correct then press down, use both hands if needed, it is a good idea to hold the rods as well so they don't bend down. It will sit firmly and will snap over the bearings. Once installed there should be no play in the carriage against the bearings.Install the fan duct from below using 4 x 8 mm M3 bolts.Move over the belt over the belt holder. Insert the printed belt peg. Place the ribbon cable over the ribbon cable bracket and then insert it into the PCB, not the other way around. Do this with the printer shut off. The main objective of the bracket is to keep the weight from the ribbon cable from stressing the connector. It will also help preventing the ribbon cable from dipping down too much.Now you're done with the physical installation.Time to print some files for firmware adjustments! Download the gcode files from here, extract the files and place them on your USB stick:hercules-xplus-imate-gcodes.zipIf you want to you can save the current configuration to the USB stick before you start. It's optional (you can always revert to stock firmware by printing files received by Qidi support). Print this file:output-configuration.gcodeNext, there are two files to print. First the firmware, then the PID tune. So go ahead and print the firmware appropriate for your printer. If you're using the motor in the BOM or Qidi stock motors use this:xplus-imate-firmware.gcodeIf using a 0.9 stepper motor you should prin tthis instead:xplus-imate-firmware-optional-0.9-degree-motor.gcodeJust place it on your USB stick and print like you would print a normal model. It will make adjustments to the motor directions, X and Y distances, E-step adjustments and finally save it all. It will save immediately, no need for a reboot.Caution! If your Qidi firmware is recent (4.2.14.x or later) skip the PID tuning step completely, the printer will work fine with the stock PID values. A bug in the recent Qidi firmwares results in PID tunes not working properly.I've made an auto PID tune gcode that you just need to print, you no longer need to connect Octoprint and send the commands to the printer and watch the output and apply yourself. Print the file, it will heat up to 230 degrees in eight cycles then use the output result and apply to the printer immediately, no need for a reboot.pid-autotune.gcodeIt will take a few minutes to run so be patient until it finishes.My firmware adjustments does not change the max print temp which is set to 300 C but it is commented in the firmware if you want to increase it (at your own risk).Now it's time to check the functionality. First, do a manual X, Y and Z adjustment and see how the carriage moves. If everything looks normal heat up the extruder to printing temps and feed in the filament using the load menu. If everything goes well it will now extrude from the nozzle.Level the bed and you're done.Important! Screw down the bed leveling screws quite a bit first because the carriage sits a bit lower than stock so you must lower the bed a few mm. If you don't, the nozzle may crash against the bed! Also, remove the bed sticker on the first attempt so you don't accidently run into it.All done. Enjoy!Just a few tips on settings. The Dragon hotend does not need as much retraction as stock Qidi. I find around 0.8-1.0 mm is good with a retraction speed of 25 mm/s, depending on filament. If you get blobs on layer changes, disable "travel prime" in your slicer.Also, print a few flow calibration cubes and temp towers for your filaments to dial in your printer, I have everything you need, check my other designs.If you have a dial indicator you can now insert it to the holder and run the bed leveling script.Videos and Test PrintsCouple of test prints using Hercules. Black one is a hollow calibration cube with 0.8 mm walls. This is used to dial in extrusion multiplier / flow. It's a bit difficult to tell from the pictures but it looks just about perfect.The blue piece is a retraction test model for a 0.4 mm nozzle which was used at the moment.The orange is Prusament Polycarbonate (Blend), also a flow calibration cube.I'll post some more test prints later.