Well scrimper, thanks VERY much for the compliment, but I'm not sure that's true! Unfortunately he's gone away now, and removed his posts as well, but member Claymore really DID produce some superb work. I'm certainly NOT up to that standard, NOR do I approach your own level of skill when it comes to fretwork either, Sir. But thanks for the compliment anyway.
What I've tended to do is all sorts of jobs which on the face of it, have little to do with "traditional" scroll saw work - like bits (mainly THICK ply) for the kids pedal car I'm (still) making. AND such things as dust extractor/hose adaptors as an example of other "non-scroll saw" work.
But to get back to the question raised by Rustic Mike, my own machine (an Excali 21) will take all sorts of blades, including bits of broken band saw blades, and mine will cut thick stuff - 26/7 mm is the most I've cut with mine. BUT as scrimper says, it IS slow work, and I don't know if the Hegner can be persuaded to take, e.g. band saw blades. Scrimper will know I'm sure.
But whatever the blade and machine, my guess is that 2 x 12 mm is pushing it a bit, and IF possible, you'd be better off doing that thickness with a small band saw or even a jig saw - OR, of course, cutting your 2 x 12s out twice!
(sorry)!
HTH