I have the same question and came to this forum tonight looking for a job sheet to cut new spoil boards. My AR8 spoil boards have lots of use left in them, but I decided to copy an idea I saw on the Woodsmith YouTube channel: .
Briefly, today I cut a second set of spoil boards from 3/4" MDF using my table saw (five 3-3/8" and two 2.5"; 48-3/8" long). I used my drill press to drill 1/2" diameter holes to match the hold-down screw holes in the existing spoil boards. I will glue these to the existing spoil boards and resurface as needed until this layer of MDF is used up. At that time I will repeat the process.
Looking to that next time, it would be more convenient to cut the next generation of spoil boards on the CNC. Today's spoil boards are "good enough", but not precise, and I could have been doing something else while my CNC was drilling holes.
To you folks at Axiom, can you provide the exact dimensions and hole locations for the spoil boards? Also, I cannot find MDF of the same high quality that shipped with my CNC. Where do you get the material and what is it?
I know it as Medite. It is a MDF but nothing close to the stuff at the big box stores. The stuff at those stores is very fuzzy after milling and loves moisture. Expect substantial changes with humidity changes.
You want a moisture resistant MDF that cabinet shops and door manufacturers use. Look in your area for a specialty lumber supplier or contact a local cabinet maker and ask them about MRMDF. Rather pricey stuff. Mills beautifully and not just for spoilboards.