I'm thinking that using the distance and bearing setting you could send minelayers out in a pattern, perhaps even autofiring by using launchers of reduced size, set the ships speed so that by the time they have reloaded they're at the right distance for the next mine.
I'm not very well versed in the use of formations, but I have one idea.
Create 6 mine layers, send them to the jump point you want protected along with one other ship you can use as the protected threat axis task group. Set a waypoint at the jump point.
Split the minelayers up into 6 groups, then give each one a 60 degree offset, so 60 clockwise, 120 clockwise, 180 clockwise, 60 counter clockwise, 120 counterclockwise, and no offset, , or 5 degrees if no offset doesn't send the ship off to the right distance.
Set them to a long distance, say 2 million kilometres. The ships will go off towards that position.
Now you want the first stage of your mines to have a short range, let's say it's 100,000 kilometres, Assume we have size 10 mines and the launcher has a reload of 300 seconds. We design the mines to have an active sensor capable of picking up the intended target at 50,000 kilometres.
What we want is to drop one salvo of mines every 100,000 kilometres, so we set the mine layers speed to 333 km/s so that in the 300 seconds it takes the launcher to reload the ship has travelled that far..
We wait until the ships are 100,000 km from the waypoint, then order them to fire and allow autoturns until they have reached the end of the formation, what we should see is 6 rays of mines spaced 100,000 apart, 20 points deep. Of course this isn't exactly the most efficient pattern, as we get further from the jump point the field is less dense, instead what we could do is leave all the ships at a 100,000 offset from protected task group, then send that taskgroup around a circle of waypoints around the jump point, send that ship at 333 km,s too.
The pattern that should develop will be more interesting, I'll test this later. BTW I think I found the post I was looking for, the images are broken and it doesn't seem to use formations like I thought it did and hence is about as micromanagey as what I came up with.
That took a while.
I first set up 14 waypoints in a semi circular fashion, and had my ships move between each waypoint at a speed of 10 km/s. Then from the individual unit screen I had both minelayers fire on the waypoint at the jump point. So that was reasonably easy to set up, but every 3 hours the simulation stopped. I forced 30x 3 hour turns a couple of times to get the pattern you see.
TLDR: I think the simplest way of doing a dense minefield would be setting only 3 minelayers 120 degrees and a certain distance apart from a central ship, send that ship in a rough spiral of waypoints around the jump point, then use autofire to dump the mines towards the jumppoint.
