Because my main-goal is to create a large variety of tools for my CHANGER I've created an assembly file with all designed tools. In Addition I've measured the toolplate offset relative to the endstop (z-Endstop). The centerpoint of the toolplate is then added as a individual coordinate system which allows to quickly output the offset of new tools. In order to get the offset of a tool you just measure center of the nozzle, spindle etc. relative to the coordinate system and you'll get the values for Duet.
The dragknife is one of the reasons why I've always wanted to build a toolchanging motionssystem. The dragkife allowes you to cut tape for labeling and more important (for myself) allowes you to cut adhesive tapes and sealings in different shapes. The dragknife is a perfect addition to any modern workshop.
Now with the whole build almost complete I want to solidify the motion system with more metal parts
Initially I've used PLA-parts. After some time I've designed a second version of the tensioners to be printed in my SLA machine but wasn't satisfied either.
Tensioner right (with endstop)
I've used the tensioner from E3D as a reference and rebuilt all the parts to fit into the CHANGER. Because I don't like sensorless homing I've added a microswitch for the Y-Axis. That's actually the reason why I've stayed with PLA-parts for so long because I've integrated the microswith directly into the old tensioner design. Yesterday I've had the idea to use a spring on one side to not loose the tensioning feature. Now you're able to tension the belt ''trough'' the microswitch mounting hole without loosing the reference.
Tensioner left
On the other side the tensioner is identical but without the need of a microswitch for the Y-Axis.
In the next days / weeks I'll wait for the machined parts and I will start testing on actual printing / laser engraving and cutting.
To prevent dust from enterning to the lower compartment of the printer (Z-Axis stepper, PSU, Raspberry Pi etc.) I've added some filter mesh on the inlets/outles with magnetic strips to quickly clean the filter.
For the slot feature to work you'll have to adjust the aluminium-profile body of the laser module as well. The implemented laser module will look like that:
Required adjustments
Milling of the ToolChanger receiver (illustration above)
Milling of the aluminium housing of the laser module
Milling of the housing for clearance of the coupling mechanism
After some printing the topcover is finally completed (from the fdm point-of-view). I'll order the acrylic panels soon (drawings and dxf-files already prepared)
The frame of the topcover
The pin feature of the top and middle-section is slightly off that's why there is a clearly visible gap on the both top parts. I'll try to better align them or even glue them together to eliminate the misalignment. I think the misalignment comes from the drillout because the tilted boreholes where slightly to tigtht and I had to drill them out manually.
After some printing (roughly 60h) there's some progress visible...
Some impressions:
All parts are designed in a way that there are minimal supports needed as you can see in the picture above. This angle without support and 0.2mm layer-height is no problem at all.
The back portion of the topcover is printed and assembled and I think it could look good. I didn't order the panels yet because I want to see if I'm fully satisfied with the look of it.
As mentioned in the previous log I've designed a cable bushing to prevent the cables from taking damage due to vibration over the lifetime of the printer.
It's not perfect (I could have switched the + and - of the 12V OUT so that there is no twist but I've noticed that to late in the process. But afterall I'm quite satisfied with this style of cable-bushing with the TPU-innerpart for better cable protection.
I initially planned to create/design proper cable bushing for all the cable openings but never designed the actual cable bushings. I've implemented the threads in the sheet metal parts but didn't design the actual bushings.
Status quo
The opening for the 230V-Input, 12V-Output and 230V-Heatbed is the first one which I want to improve.
Design process
For this opening there should be five cable bushings in total:
- 3-cables for L , N and PE of the 230V (I'll change the color as soon as I get the right cables) @3.5mm
- 2-cables for + and - of the 12V for the Duet-Board @3.5mm
- 2- cables (insulated) for the 230V-Heatbed @3mm
I'll continue with a two piece design of which the first part is shown above. It consinst of a robust Mainpart (picture above) and a elastomeric inner-part (in process of designing)
The three TPU bushing inserted and ready to be tested. The bushings are nearly split in half so you can easily insert the cables and then push them inside the housing/cable bushing frame to secure.
At the end there is a small lip which should interlock with the cable bushing frame to ''lock'' when fully inserted. We'll see...
Simon Wirz
