Should be able to do a metal plate.
I just realised I need an rpm display in the vid, ouch!
Looks like the 240V to 5V wall wart trans isn’t any good.
It’s ferrite core and has 3 separate windings :-
1 - 0.3 ohm 0.05mH
2 - 1 ohm 0.6mH
3 - 9.4 ohm 4.7mH
I’ve got lots transformers out of a ATX PS , but now I’m thinking anything with a ferrite core isn’t going to work.
I don’t see the average Joe building this using simple Ebay/Ali or from their local elec shop, because parts are a real PITA to get. Unless you want to pay high prices at the big wholesalers - it’s cheaper buying the timing light - , no high voltage caps - 100V max -, only 1 horseshoe Xenon, and 1 maybe 2 transformers. I think the death of analogue is killing this. 
Looks like LED is going to be the only option, so I’ll have to sort that out properly.