Vertex K8400 Print-head Mount Redesign

thingiverse

One of the major drawbacks of Velleman Vertex K8400 printer is the absence of a straightforward way to take out and reinstall the print-head. In fact, you have to disassemble about 80% of the printer's moving parts to do this. Then after putting them back together you need to re-align rods and pulleys. Additionally, placing clamps at fixed distances of 33.6cm and 32.8cm during initial printer assembly, or if you had to remove print-head from the rod is a separate challenge, because the print-head gets in the way of the measuring tape. In this design I addressed all these issues. IMPORTANT NOTE: I designed and tested these things on modified K8400 printer with GT2 belts and GT20 pulleys (details are here). While I am providing part_1_T2-5.stl file designed for the printer's original T2.5 belts, I have nowhere to check how/if it fits. Apart from this, please consider that part_1_T2-5.stl houses two ends of the belt, i.e. you can use the original belts only if you cut them. I'd rather suggest purchasing T2.5 belt online and using it instead. If you use this design with T2.5 belts and original pulleys, please let us know how it worked by leaving a comment to this post. Parts: Twenty M3 x 16mm socket cup screws. You will re-use 16, so need just 4 additional. Eight M3 x 20mm socket cup screws. Twelve M3 self-locking nuts. UPDATE 10-Feb-2019 Added parts allowing to use LM8UU linear bearings. Part_4 is based on the original part design called 'XY LINEAR BEARING CLAMP 1'. Print Settings Printer: VERTEX K8400 with E3D print-heads Resolution: 0.1mm Infill: 25% Notes: Use touch-bed support when printing part_3. Post-Printing Assembly Instructions Push three M3 self-locking nuts into cutouts of each part_3. Remove all 6 rods Disassemble clamps. We will reuse outside section of the clamp, linear bearing, the screws and the nuts. Using the original M3 x 16mm screws attach part_3 to the outer clamp. Pay attention to the orientation (see images). Make sure bearing fits inside and there is no gap between the original clamp and the printed piece. You may need to use a dremel tool to remove the remains of support structure. Cut 4 pieces of GT2 belt. 2 pieces that will be installed along the sides of the printer should be 662mm in length each. Other two - 644mm each. Push 8 teeth from each end of the belts into part_1. Install one outside rod. Make sure you put all the pulleys, clamps and belts on it in the right order. Then do the same for the opposite rod. Repeat for other 2 rods. Now your printer should look similar to the 1st image. Move the belts closer to the sides of the printer and connect part_1 things to part_3 with M3 x 16mm screws. Mount two rods holding the print-head. Attach rods with part_2 thing and M3 x 20mm screws to part_3 things. Align the rods and tighten pulley screws. I use this carriage alignment helper, it is really handy (see the 2nd image). That's it! From now on, should you need to remove print head, just unscrew part_2 things and voila - you are done. Alignment and 4 outside rods remain untouched.