Close-up of the arms and spacer
The arms are made from a coat-hanger. It has square 'hoops' so that some beans go over, and some go through.... great for very small batches. Useable range of batches; 110g to 410g.
The spacer is 1" aluminum strip from Home Depot. It's secured with 3 small screws, the last third is unattached so that it can be propped open.