Originally Posted by sledhooligan
I really need some oar lock designs. The ones i've seen are pretty primitive.
The only designs I have are probably what you call primitive. My first experience with a sweep boat was a 14 1/2 foot Maravia on the M Fk S. I found enough oars and cobbled them together to make a couple of sweeps. I have a small breakdown frame that I took apart and lashed the 4 ft long double side rails to the ends of the boat. I stood and stacked gear on a sheet of plywood that I used as a floor. It just had open oar locks but they worked fine at low water with a fairly light load.
The boat I use now is based on 20 ft x 30 inch cat tubes. Like you, I run it as a sweep on the MFS (3X) and as an oared gear boat on the Grand (only once, but going again in May). I use a 12 ft long, 2 bay frame with a full length diamond plate floor. Yes the frame is heavy, but since the center compartment is mostly unobstructed, I can load just about anything into it. The floor sits a foot or so above the water so I can straddle rocks. Most sweep oars are bent near the lock so that they can reach the water without being too long. Yours will need to be bent since your locks will be 20 ft apart. My sweeps aren't bent since my locks are only 12 ft apart. The sweeps are just a couple of Carlilse oar spliced together with an aluminum sleeve and bolts. I added a broken off Cataract counterweight handle to the front sweep to adjust the length and for balance. The back sweep can dangle in the water, but most of the time the front sweep is out of the water hence the counter weight. I use Carlisle outfitter blades just because I have lots of them, but I have been thinking about making a set of more traditional sweep blades. I started with open oarlocks on my larger boat but soon realized that was a bad idea. If you are not paying attention, the front sweep will turn horizontal and head for the bottom of the river. To prevent this, I switched to pins and clips. I mounted the pins through an aluminum block welded to an upsidedown U-shaped upright made from aluminum plate and 2x2 tube. The uprights slip over the front and rear frame members, which are also 2x2 tube, and are bolted in place. The uprights have a series of holes drilled in them because I wanted vertical adjustment since I had no idea how tall they should be. Whatever you do, be sure to secure the sweeps so that they do not spear you. I secure mine with a strap wrapped around the sweep shaft and through a carabiner at the base of the pin. I learned this the hard way.
Good luck with your project. Let me know if you get a permit and want to have a sweep party on the MFS. Anyone else need a gear boat for a mid July MFS trip?