Well, OK, two people asked so I am posting here because I am a geek.
On the bike-packing trips I have used a Topeak Explorer Disc rack fudged and bludgeoned into fitting onto my Vassago Bandersnatch (no rack eyelets). I'll geek out over this a little bit now, so if you feel your eyes glazing over, a shortness of breath, or the sudden urge to wear tight pants in public, stop reading now.
Here is a picture of v1.0 on the trail (kinda) last Sept.
And here is a close-up of my home-made OMM skewer-attachment system for v1.0.
The steel (painted black) L-brackets worked OK, seemed well and truly strong enough, but they were a tad flexy. Yanking on the rack side-to-side produced a bit of flex, but had no detrimental effect I could find riding. The metal did seem a bit slippery however, and the LHS tab began to rotate when I got a bit carried away on some fun singletrack (=jumping). Regular/mellow offroad touring wouldn't have been a problem. I stopped and realigned it, and was able to finish the weekend without further hiccups.
Over winter I periodically tried to think of how to stop the tabs from rotating, and then one day in my LBS I found the answer:
Here are the tabs on v2.0 - the gold coloured bits. As you can see, they have built in anti-rotation tabs! Cost about $6. I crimped them a bit tighter to fit snugly around the foot of the rack. Ride two (March - again with some rough ST) didn't see any movement at all, thanks to the tabs but also this metal seems a lot less slippery, so I think the frictional resistance to rotation provided by the bolt's tension is a lot higher now. I'm covered both ways anyway, so I think I'll be good.
There are two more important parts to the homemade poor man's OMM rack (PMs OMM R) - one can be seen in the above photo.
1. That's a homemade extralong QR skewer, made from about $1.50 worth of threaded stainless rod from the hardware store. I had a Bontrager skewer where I could unscrew the QR shaft from the QR lever itself, so it was easy to replace with the required length of threaded rod. I've used a combination of washers and old shock-mounting hardware to space the tabs out to clear the fame and disc brake. No slippage - works fine. Plenty of grip on the dropouts - the axle hasn't moved at all in several hundred km, half of which was loaded offroad.
(please note that I cut the feet of the Topeak rack shorter as it was ridiculously wide, and cleared the brake caliper by about an inch, and also drilled the hole in the foot of the rack for a bigger bolt. I think this will render the rack useless for mounting on regular frames with rack eyelets...)
2. The second and last important bit of the PMs OMM R is the mounting system at the other end; it looks like this:
The rack mounts to the ACOR seatclamp shown, which has built in rack mounts - brilliant! Sadly, it is the wrong size for this frame (it's for a 31.8mm seat tube, if I remember correctly and I can't find one for a 30mm seatpost ANYWHERE), but here it is shimmed with a bit of seat tube from an old frame, and works fine. The Salsa clamp is still holding the seatpost in place.
So there you go. Here is a photo of the final setup of v2.0.
Notes: v2.0 is much laterally stiffer. It is also slightly higher, which could be a good or a bad thing, I've only noticed positives (more tyre clearance) so far. It's almost tool free - only requires one 5mm allen key to install, and takes less than 5 minutes. I like this setup - all up it is still much cheaper than an OMM rack, I can still use regular panniers if I want, and also the integrated Topeak bags that slide and click into place on the rack - I like them.
Hope this helps. Cheers.
