Parametric Spoolholder for Anet A8 type printers

Very preliminary parametric version of my Dovetail Spool Mount for Anet A8 and similar printers.

Generate test pieces by setting Piece to 4 and 5. Use these to adjust "looseness" parameter.

Looseness of 0 will probably be impossible to assemble, but this of course depends on your individual printer. Mine is not calibrated very well, so I use a looseness of around 0.2. I think a well adjusted printer might work with about 0.1. Print the two test pieces with varying looseness until you get a satisfactory fit.

Once you have a looseness selected, print Pieces 1, 2 and 3 (don't forget to set the looseness each time).

You can also choose to add "anti-warp grooves", which are meant to reduce the possibility of warping due to poor bed adhesion.

And of course you can adjust the height to support larger or smaller spools. Currently heights higher than 150mm aren't really supported, the lightening holes won't be positioned very well.

The last parameter ($fn) adjusts the number o