I have the Ryobi ELT1100A 1100W electric trimmer which I hated the bumpfeed head it came with and wanted to replace it with a fixed line head. There are few fixed line replacement heads on the market but I thought I'd make my own.

I used the MTM 3.1mm Pre-Cut 35cm Trimmer Line from https://www.edisons.com.au/orange-35cm-100-pcs-pre-cut-square-edge-trimmer-line/ The head can be used with smaller square or round lines. When mounted the 35cm line is ideal length for this head.

Initial prototype printed using ABS with the following settings, Layer Heiht: 0.2mm Shell Thickness: 0.8mm Fill Density: 15% Print Temp: 240C Bed Temp: 100C Fan: Off

Although printed at 15% fill density to test the fit, I ended up using it for a day and it worked a treat.

I will be printing another head with 75% density and thicker walls as a final product. Knob printed at 100% density for extra durability.

The Ryobi ELT1100A did get a little warm on a 30 degree day with the additional thicker line, but it did well for about 2 hour of continuous work.