Did you do any sort of rigid frame on the inside of the braid?
sounds like you opened the spigot to much. the grain compacted and is holding back the wort. if there's enough wort left blow back into the tun then recirculate the wort a few times till its clear again. then drain again.
been draining for at least 20 minutes so far...barely trickling and still have the sparge to do. I am using a SS braid in a cooler. Any suggestions for the next batch?
If you are using a 1/2" braid, my suggestion would be to swap it out for a 3/4" water heater supply braid. I mash in a 52qt Coleman Xtreme, I have had over 21 lb grain-bills ontop of my braid w/o any run-off problems.
How big is too big? I know where I can get some 2-1/2 inch stainless braid....may be too expensive however. ...ALSO will the slow run off and the stuck sparging effect my efficiency? Or is it just a time thing?
Slow run-off times shouldn't reduce your efficiency. It really comes down to just taking longer and extending your brew day. If anything a slow run-off may help efficiency because your wort is staying in contact with the grain longer allowing conversion to continue, so if comversion wasn't complete, it could help get an extra .001 maybe. It is probably negligeable, but it won't hurt anything.
The problem is this: with a braid, you can only siphon to the level of the TOP of the braid. The larger the braid, the more deadspace in your mash tun.
Braids don't really create a siphon.
It will drain to the lowest point of the outlet. Basically, with a weldless fitting, your tun will drain to the lowest point of the coupler inside the tun.
sounds like you opened the spigot to much. the grain compacted and is holding back the wort. if there's enough wort left blow back into the tun then recirculate the wort a few times till its clear again. then drain again.