Ever since I saw the Ridgid Root Ranger in action at last years' Roundup I've been jonesing for one. I just couldn't justify the $300+ price tag. So I 'value engineered' one
I tried to build it by using two 1/4" street 45's and a street 90. That works, but it's way too wide at nearly 3 1/4". Might be ok for 6" pipe but I'd be afraid of getting it stuck in 4"
So I tried two street 90's and it's only 2-1/2" wide. I'll need to tack weld the 90's so they don't spin on me in the pipe

and add a weighted nose piece. Not sure what to use there

Regular rotary nozzle paired to the specs for my machine with zero degree head on a 25 degree pattern (about $30 from Water Cannon)

Same nozzle with the cover removed.

Little too wide at 3-1/4"

This is the prototype version I named 'The Ghetto Blaster'
Untested final version