I finally found my setup for sounding on my fucking machine, but then I broke it (the glue joint failed) and had to fix that. I've got the pictures and explain it now.
What I did was take the vac-u-lock adapter off the thrust rod of the fucking machine (F-Machine brand) and replace it with a 5/8 inch drill chuck to hold various sized sounds. Here is the normal setup of dildo and vac-u-lock adapter:
Vac-u-lock adapter by itself:
It has a hole in it with a M8 metric thread.
I replaced the vac-u-lock adapter with a 5/8 drill chuck which has a 1/2"-20 hole in it for attachment to a drill. So I had to convert that to a M8 metric threaded hole to attach to the end of the thrust rod. To do that, I connected a 1/2"-20 bolt, 1 inch long to a M8 metric "rod extension nut". Preferably these would be (tack) welded together, but I can't weld (if you can get someone to do this for you, do it). So I glued the two pieces together with epoxy glue. I mentioned no tools are required to do this job, but that's not entirely true. The mating ends of the bolt and the nut have to be ground or filed flat for the glue joint to hold. When I fixed it after it separating, I also cut a couple of small grooves in both the bolt and nut mating surfaces to give the glue more grip.
Drill chuck on left. At top right are the bolt and nut not yet glued. At bottom right are the bolt and nut glued together.
Here is a close up of the bolt and nut glued together:
Here is the setup mounted on the fucking machine, with a Dominator Bullet 2 in the drill chuck:
Here is a closeup of three different sounds in the drill chuck:
The sounds from top to bottom are a Dominator Bullet 2 (about 12mm max), a Dominator Bullet 3 (about 16mm max), and a Hegar 15mm/16mm sound with the 16mm side in the drill chuck. 16mm appears to be the maximum for this 5/8" drill chuck. The 17mm end of my Hegar 17mm/18mm sound would not fit.
Here is the box the drill chuck came in:
I checked today and you can get this exact same drill chuck on both e-Bay and Amazon for under $24 including shipping. You could also use a smaller drill chuck, say a 1/2" one if you don't want to go to larger sized sounds. It would be lighter and put less strain on the glue joint (among other things).
Searching e-Bay or Amazon for "drill chuck" and the part number "J3516A" should locate one for you.
You should be able to get the bolt and nut at a hardware store such as a Ace or True Value. The M8 metric rod extension nut would be the most difficult item to find (the drill chuck and the bolt are easy).
Other brand fucking machines might take different sized components, but the general idea would be the same.
I've only used the Dominator Bullet 2 sound so far with this setup and that might be all I ever do. I have larger sounds, but my eyes are bigger than my peehole. I have gotten a 14mm Hegar all the way in, but it was work. Due to other issues in my life, I can't spend as much time sounding as I might like.