Dropped down from the 10.5mm lightpipes (the focus lamp pipe) to 5.6mm for the strobe light carriers...8 or 9 10.5mm pipes were too stiff. 8 pipes each lamp off the z240 for 16 total. 3D printed the 'cuff' for the port end and the strobe face cover and pipe mount. The strobe face cover attaches to the z240 with stainless hardware using the same threaded holes as the diffuser that comes with the strobe.
This might almost be too much light. Shots at 1/160th, F10-12, ISO400, and the strobe set at minimum manual setting (EV -6.0, 1/64th of full dump) are about as brightly lit as I think I'd want in a dark room. I actually have to use the focus lamp in that condition*. That leaves plenty of headroom for even narrower apertures and/or lower ISOs.
Sending one off to a beta tester in the next couple of weeks, hopefully can get some feedback of things that need changing before my own first dives with it (trip in late April planned).
Pics up at Flickr:
...using the Ikelite 5505.58 for a Sigma 105mm macro and an Inon Z240 Type IV.
The Saga ring flash (certainly much better built, with more but much smaller fibers - no idea of relative light transmission) runs something like 800 euro I think. This one, if I chose to sell it, would come in at significantly less than half that, if there was any interest. Will await my beta tester's comments and my own experiences in April before I consider it for real....but feel free to PM me if you just must.
[* My camera is the Sony SLT-a55, which was from their first generation SLT's with the electronic viewfinder (EVF). These cameras have a 'helpful' feature that takes into account the exposure settings and darkens or brightens the view in the viewfinder accordingly, kind of a pre-shot preview or 'what you see is what you get'. UNFORTUNATELY the camera doesn't know when you have a manually attached strobe (no TTL communication)...so manual settings like the above result in a black viewfinder, although the camera has plenty of light to autofocus etc. The SLT generations that followed have a menu setting to turn off this 'help' in the EVF so it always shows a reasonably ambient picture (I don't think they cared/thought about underwater phtogs but studio photogs sure complained that the first generation didn't work with remotely triggered strobes), but mine alas does not, hence I get to use the focus light under circumstances like this. I may have to adjust a subsequent build of this part to have fewer pipes and provide a little less flash (and just don't get to dial the strobe down as much).]

