Thinking of expanding my 16ft double rail frame to fit my 18" canyon raft for a Jan Grand Canyon launch in 2016. I have a 4 bay frame currently made with the 1 5/16" OD 6061 NRS size tubing and hve been using the T-clamps from Frontier Play. I like the T clamps better than NRS ( or the"speedrail" fittings w the tiny set screws that seize up and strip out, my least favorite frame fitting!!).
I know the t clamps are heavier as they are cast iron, but they are half the price of NRS, are easier to install and adjust, have a huge stainless set screw which in 8 years of use and many adjustments has never seized, stripped or failed (I put anti-seize lubricant on the threads). I do not know enough about engineering to understand which material has the most strength and proper flexibility for rafting/flipping/pinning situations. I was hoping some mechanical engineer types or other knowledgeable folks might be able to break this down for the rest of us to be able to understand.
Not worried about weight, so much as the best strength for a bomber 18 ft double rail frame which is going to hold a huge amount of gear in an overloaded 18 ft boat for a 30 day trip. With the double rail design, there will be a lot of stress put on the inside fittings which will be hanging in air space (and holding up weight of giant cooler, dry boxes and drop hatch) vs the outside fittings which will be directly sitting on the main tubes of the raft.
I have another frame with 10 of the older NRS lowpros I could swap out with the t clamps I already have and then buy 6 more to get the 16 total I will need for my frame design, if that would be the best choice. It would be nice to compare the older low pros to the newer low pros to the T-clamps.
Please do not get into the american vs Chinese deal, just like to know which has most strength. I have done business before w Frontier Play and with NRS and know them both to be awesome to deal with and have great boating gear, thanks!!
Here are some links for the parts:
Frontier Play T clamp made w BS EN-1562:1997 weldable cast steel BS 3100:1991 w galvanized finish https://www.frontierplay.com/TClampQuickFit
NRS New Lo Pros: Hot forged 6061 aluminum NRS LoPro Frame Fittings at nrs.com
Old NRS Lo Pros Cast aluminum ???
My best guess is the old lo pros might be the weakest as cast iron steel is probably stronger than cast aluminum and also less brittle???
Not sure how the new lo pros compare to the t clamps???
Thanks so much for your help!!!