Are you deleting files so they show up in the recycle bin or are permanently deleting them so the only way to get them back is to use recuver and the like?
If you are only sending to the recycle bin and not emptying the bin your free space will not change.
Also there are real files and there are pointers also known has soft and hard links.
You can delete a link but that does not delete the file, a good example of this is the sxs folder in windows. This folder usually only contains links and not files so if you delete anything there (BAD IDEA) you don't actually create any disk space.
Main machine: Core I7 -2600K @ 4.0Ghz / 16 gig ram / Radeon RX 580 8gb / 500gb toshiba ssd / 5tb hd
Old machine: Core 2 quad Q6600 @ 3ghz / 8 gig ram / Radeon 7870 / 240 gb PNY ssd / 1tb HD