What do you call external scotia?

[Penners]

Interesting suggestion about the DIY feather springs Penners, I wouldn't have thought ply would be springy enough because of the ways the grain of the various layers are arranged. Perhaps birch ply is different somehow? I've got plenty of 18mm WBP ply so perhaps I'll give that a go.

I've certainly made them from birch ply, FF, although it was some years ago and I'm relying on a fallible memory for the thickness of the feathers. If you find that your feathers are just too rigid, slim them down a bit. They don't have to flex by very much to be effective. You can also use ordinary timber, but in my experience the grain makes it more likely that the feathers will snap.

For moulding, a router table is a good compromise against the cost of a spindle moulder. However, with the right diameter of cutter block a spindle will give you a higher tip speed, hence a smoother finish. When I used to use a spindle moulder you could still buy unserrated clamp-type Whitehill blocks, which allowed you to fit your own cutters, ground out of high-speed steel. These could be honed to a much better edge than tungsten carbide. However, I don't know whether this type of block is still permitted.

 

[kreyszig]

Everything I've read regarding diy feather boards has recommended ply, birch at that, and a 30 degree cut.they do look a lot nicer than the plastic too!
I've seen a small spindle moulder on the interwebs for under £200, I imagine with a bit of creativity you could increase the table size a la the diy router table route; namely whack it or at least the motor under a decent sized piece of ply, could bd quite cost effective.