After success with my VertexEvo project, I started to look for ways to simplify kinematics of Vertex K8400 even further and at the same time (hopefully) increase the print area. It appears H-bot design can help to achieve both these goals.
Update 9-Oct 9-2018 I am at the early stage of the design and posting the image to show how it may look. Single 9mm GT2 belt is aligned vertically with the centers of both - X and Y axes. MGN12H rails replaced 8mm round roads. I will be updating this post as I progress. Stay tuned and feel free to comment. I am open to your suggestions.
Update 15-Oct-2018 Completed design. Looks promising :) Started printing parts...
Update 23-Oct-2018 Assembled and printed few Things. Used the same firmware configuration as for VertexEvo; just changed Xmax, Ymax and Zmax. Had about 50% successful prints. Another 50% failed with printhead shift along XY. It can be caused by insufficient belt tension or too low motor current. Investigating...
Meanwhile here is the list of parts (screws not included):
- 3pcs MGN12H Linear Sliding Rails 300mm. You will need to cut 2 of them to 280mm length. Bought on eBay from seller renshuiyuan.
- GT2 9mm belt 183 cm (6')
- 2pcs GT2 Pulley 20 Teeth W=9mm bore 5mm. Bought together with belt on eBay from seller powge
- 2pc GT2 Idler Timing Pulley 20Teeth W=10mm, 5mm bore
- 4pc GT2 Idler Timing Pulley with no teeth W=10mm, 5mm bore. Bought all 6 pulleys on eBay from seller liansgcun20173
- 2pcs e3d v6 hotend from https://e3d-online.com/ Chinese clones may not fit.
I bought MGN12H rail clones and had to disassemble and clean them. Followed these instructions https://www.youtube.com/watch?v=c53sa46C1qQ One rail was completely unusable, but the seller stepped up and sent me replacement for free.
Update 28-Oct-2018 Layer shift issue was fixed by reducing motor current. Making minor changes to XY clamps and printehead.
Update 31-Oct-2018 Redesigned PCB and uploaded gerber file. Ordered PCB from https://jlcpcb.com/ Once it arrives will publish the images of assembled PCB. Published all STL files. Will write detailed description and upload actual images later this week.
Update 4-Nov-2018 Uploaded video showing Vertex-H at work https://youtu.be/o6aHJYE-vaw
Update 8-Nov-2018 It appears that 25mm fan is not able to cool down e3d. This is causing nozzle clogging. Will need to fit in 30mm fans and redesign the duct.
Update 14-Nov-2018 This project is complete. I uploaded 24 images of my Vertex-H. I will update few STLs (hopefully) later today and will add description. I designed print head version that uses original PCB from Velleman, so you don't need to order custom PCB.
Before you start converting your Velleman Vertex K8400 into Vertex-H, please be aware that this is major modification that requires drilling, rewiring and soldering. While in most cases you should be able to roll back to the original K8400, I cannot be responsible for any damage done to your printer as the result of applying this MOD. All repair associated expenses, both - cost of parts and labor (if any) will be paid by you. Remember that most expensive part of your printer in mainboard. Make sure to unplug printer from main (AC) power while doing any work on it.
Please consider that this MOD was developed on top of dozens of other MODs that I've applied to the original K8400 earlier (see my other posts). I cannot guarantee that the result you will get when directly upgrading the original K8400 into Vertex-H will be the same as mine.