Yes , I think your wasting your time with that light webbing, 70mm is about 45lb test. If you can get a look at anyone of the guy's webbing you'll get a idea of what size there using. Just remember it's not gonna rip off a log to easy. I have new 300ft bales of 6 3/4 that would probably rim rack them but if you got hung up you'd never get it back without a net drum. Our nets are all special ordered and right now it's taking close to 7 months to get just the webbing, I hang my own. But yes your gonna have to go heavier. There's got to be someone to at least tell you what mm their using.

Memphis is expensive, https://kellerfishingsupply.com/ , Keller's sometimes has webbing on hand, you can reuse your cork and lead lines , hanging is pretty simple, make a gauge , mark your ties.

If they are like carp you have one chance with a seine.............after that they know the game plan.
You have found that out with your blocking off a peninsula. They know outboard motor noise..... guys here use a rope across the two points and hand-pull the net across for the blocking, no motor running.
Cohunt should be a wealth of knowledge with this stuff since it was his line of work for 40 years. I was only the tiger flusher on the deep end of the net.

check out Leckie's in Winnipeg for comparisions.

Memphis is a good outfit that sells quality products so the nets you have should be good and if the mesh sizes you are using are the same as other successful area fishers the problems must stem from either your technique or your locations. The carp are smart for fish and can be very spooky and if you are observing numbers of fish jumping your float lines then I would say for sure they are seeing your nets. Lake whitefish in super clear Lake Superior lead on nets and can be difficult to catch except in fine monofilament nets. That will not be an option for the size fish you are hunting. Since you likely must continue to use the nets you currently have, I would suggest(as I did above) that you seek areas with dirty or stained water where the visibility is reduced and perhaps attempt some sets where you do not drum(drive them) so hard. Those nets are hung on the half basis and with that much webbing will billow from the vertical and should catch fish that come in contact. If your regulations permit, you might try one net with larger mesh, attempt sets made in areas where you suspect concentrations of fish, leave overnight and do not drive at all. The folks making the big catches likely have worked through the learning curve and you might learn a lot from observation.

Trying to become a commercial fishermen on a key board is not the way to go. There is a large learning curve to become a fishermen let alone knowing all the other facets of running a business. Good luck, you will need a lot of it.

I would bet Matt Jones could give the answer.

As I posted earlier I have many friends that fish these carp here and many of them are fishing 3.5” square net mesh.
You are in an area with many great net fisherman in an area with many many miles of open water to fish. You can’t drive them to hard but you can drum and drive them. A close friend had nearly 50,000 pound last week.
If your willing to work for one of these guys for a few weeks you will learn much more than you will by guessing.
You will figure it out by trial and error but it may take you a couple seasons. Ronny Hopkins has spent a lifetime on this water and usually is freely giving information but he might like to trade some labor for some lessons.

^^^^^^^^^^^^^^^^^^^^^^^^^^^ Best advice in the whole thread. Trade your labor for some of their knowledge and cut years off the learning curve.^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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YES