Tooling is by far the largest expense of the spindle moulder, but then it is still more economical in the long term than table routers and router bits. You can find good deals on auction sites occasionally but very rarely as tooling tends to hold its value well, I have seen used Whitehill blocks go for more than they would cost new excluding the VAT.
My personal "essentials" list for general machining work and joinery would be:
Whitehill 96 x 55 Limiter Head, in an ideal world you want several of these but when you're starting out one will do until you get sick of changing cutters and end up needing more to save time on set up. The 96 x 55mm limiter head is the standard size especially when it comes to fitting Whitehill's own cutters for profiling joinery in conjunction with other tooling. There are cheaper imitations and other sizes but I strongly recommend keeping to the 96 x 55mm size, the cheap Chinese blocks should be avoided as they have very poor tolerances on the pin placements and the cutters will not cut in unison correctly.
Whitehill 125mm x 60mm Rebate Block, in conjunction with the 96 x 55mm limiter block fitted with corresponding cutters from Whitehill, the 125mm rebate block is the standard size for producing joinery profiles such as door frames, doors, casements, etc... The smaller sizes of rebate block (such as the 125mm x 50mm) are useful but the 125mm x 60mm allows for more flexibility in work as most modern doors are 56mm thick to account for double glazing so the door frame rebate ends up being around 61mm in depth when accounting for draught seal and a 50mm block is not large enough to remove in a single pass.
Whitehill 140mm x 3mm Grooving Saw, this is placed underneath the 60mm rebate block to cut the groove for draught seals in the perimeter of the frame, for seals such as Aquamac 21 or Deventer SPV.
Whitehill (or Omas) 160mm x 8-15mm Adjustable Plate Groover, for running grooves and smaller rebates.
Whitehill (or Omas) 160mm x 12.5-22 Adjustable Plate Groover, for running grooves and smaller rebates, with the added benefit that you can run small tenons like for shaker kitchen doors by inverting the plates to the typical arrangement.
Axcaliber 21 seal cutter or Whitehill 21 seal cutter, for cutting Aquamac 21 wiping seals in door and window frames, the Axcaliber is significantly cheaper than the Whitehill version but the Whitehill does produce a cleaner cut over the long term.
There are other blocks that are nice to have but aren't required on a regular enough basis to warrant buying them from the outset, buy them when required.
