I've use wood templates with great success with a plasma - for a quick and easy template for limited use they work well. Admittedly after a few uses, they do seem to smell a bit singedThen I had a brain storm, why not cut out between odd leg calliper scribed lines in 1/4 " scrap strip wood allow a few mm for the nozzle diameter and give it a go with it securely clamped to the bracket .... in the right position .
I chicken'd out did a tria;l burn out on a bit of the same metal scrap. Wow worked better than I'd hoped .
Third bracket is a lot better hardly any filing to get it rectangular
Forth bracket was even better , next time I'll run some 2" x 1/4 inch thick oak strips up on the bench saw make a strip for the spacer gap in the slot as wide as the slot I want then glue them up , leave to set over night in the airing cupboard and then use the mask of wood for plasma hole cutting the next day . I reckon with a few experiments and making the cutting slot just a tad bigger than the diameter of the nozzle I might be looking at 2.5 mm wide straight slots in 5 mm alu.
I dare say I could have purchased the brackets and clamping parts from somewhere after doing a few hours online searching but where is the fun in doing that and paying for them at the same time ?
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