Some notes:
1) cooking foil is too thin and has bad performance for shielding. It's better to use more thick copper foil.
2) keep shielding away from filter components as far as possible. At least keep not less than several tens of millimeters.
3) these yellow Chinese capacitors works very-very bad and have extreme high loss on RF. They are not intended to use on RF. This is very important for RF filter to use low loss capacitors and inductors. Use something like silver mica capacitors.
4) these EC24 green inductors have Q about 30-50. This is better than cheap inductors with high loss, but this is not much. So, it's better to replace it with air core inductor. But first replace capacitors, because these yellow capacitors are piece of shit.
ATC porcelain capactiors are good, they promises Q about 10000, but they are too expensive.
I designed an output LP filter to replace the stock one in an $18 kit that came with 10 xtals. The kits are $7-8 with only one xtal. The stock filter does not meet current FCC spurious emission requirements. The kit filter design dates from the mid 90's when FCC exempted QRP transmitters from the spurious emission regulations. Since then they have removed that exemption.
So after making a prototype filter to test, removing the kit filter and replacing it, I mounted the kit filter so I could sweep it to show the difference. I demonstrated with the transmitter that the kit as received did not meet the FCC requirements but with a filter which added a *single* part it exceeded requirements by almost 20 dB. I happened to use 2 parts because I did not have a 360 pF cap and had to parallel a 330 and a 27.
Looking at the 2 test boards I decided that they might prove handy one day and decided to shield them with copper foil as being a cheap and very simple method. I thought the cost and effort made it worth mentioning. I expect I shall be doing it quite often with prototypes. Left over from projects.
I posted SA sweeps showing the performance of the filters before (in another thread) and after shielding. They clearly work as expected.
Based on the *color* of the capacitors you tell me they are no good, my shielding is no good and I should use air core inductors. And do all this despite clear evidence that the new filter performs the task better than required and that the Butterworth filter supplied with the kit does exactly what it is expected to do and by analysis with Elsie can't meet FCC regulations.
Please excuse my thinking that your post absurd.
Have Fun!
Reg