Vertex Delta K8800-EXA Enhanced Run-out Detection

thingiverse

Having had my Vertex Delta for only a few weeks and after having several false "run-out" alarms from the filament run-out detector I tried to find a solution. I wasn't happy with [Velleman's answer](https://forum.whadda.com/t/k8800-unloads-filament-while-printing-and-continues-sometimes/33445/3) to someone else with the same problem (i.e. if it stops working just unplug it and don't use it) - especially since I am using Velleman's own filament - So I decided, why not just fix it?! :-) So I tweaked the extruder design (well the printer is open source after all), specifically the K8800-EXA part onto which the filament run-out detector attaches. Basically what I found was that the friction of filament passing through the part was wearing flat surfaces in the steel pins which meant that hairline trigger of the micro-switch was not quite making it. Perhaps simply replacing these pins with tool steel (or even ceramic) may work, but that sounds too easy! There are dedicated micro-switches with roller levers available which are more suited to this job. The Vertex Delta (K8800) uses a [Dongnan KW-10](https://www.switch-china.com/product/KW10--16.html) micro-switch. The one that I picked as a roller lever replacement (which has the same external dimensions as the KW10) is [Omron D2F-FL2](http://components.omron.eu/Product-details/D2F) (note that the default part shown isn't the roller lever). The 3D model is available [here](https://www.traceparts.com/els/omron/en/product/omron-ultra-subminiature-basic-switch-micro-loads-general-purpose-hinge-roller-lever-pcb-terminals?CatalogPath=OMRON%3AOMRON.050.040.060&Product=10-16052011-063956&PartNumber=D2F-01L2). It can be bought from various places, but I bought it from [RS](https://uk.rs-online.com/web/p/microswitches/6867708/). I also extended the filament guide to fill the void in between it and the roller to prevent the filament falling off the roller.