This is effectively 2 x 90° bends, I experimented with this briefly on a 60litre barrel and it sort of worked until the barrel was about half full then it failed completely as there was not enough room for the particles to "fall out" of the resulting cyclone. I have gone big! I use a 6" to 5" cyclone on top of a 400litre dust container which is powered by a high flow low pressure system which works well.
I know other turners have managed very well with high pressure low flow systems using smaller cyclones on a 56mm hose system such as this one
https://www.ebay.co.uk/itm/274596541057?hash=item3fef3ab281:g:1twAAOSw~MFfxftL There is always a trade off in these things, you are trading the loss of suction caused by the cyclone in the circuit against the gain in suction by keeping the filters clear of dust. Going big in ducting / hose size requires more HP on the suction end = more noise or more money on noise suppression.
A few years ago I made significant investment in upgrading from a 74mm extraction setup to a 120mm system, which I am fairly happy with, but it is not foolproof, I am pretty sure there is a solution to this problem, but not one that falls into my budget or space.