I was thinking more on the lines of making a partial cover that will be used to keep the rain out. One on the front, and one on the back, with the paddle area open. I've seen one before, but have know idea, as to how to make it with an arch in it, to keep the water from running into the cockpit. I'm pretty confident that I can make it, if I can find out what to use for that rise in the cover.
		
		
	 
 
Rider, you awakened my spray cover beast within. Apologies for the blather, but I am an obvious fan of partial spray covers. Keep it simple partial spray covers.
 
I have used covers with arched stays, either sewn into the cover or installed across the boat each time at the launch. I did not like them, mostly because they are problematic to transport and store. The partial covers I have from CCS easily fit in a shoe box sized stuff bag.
 
The solution on my partial covers was a Dan Cook idea. The open cockpit edge of the covers have a narrow strip of (I guess, feels like) minicel sewn into the hem. When the cover is installed the last set of snaps, set a bit lower on the hull than the other cover snaps, pulls that lip into a vertical semi circle that drains water off of the cover, over the side into the river.
 
Even if the nylon cover is rain damp saggy I can just rock the hull a bit and any pooled water flows off.
 
I couldn’t have conceived that simple, effective design. Thank Dan for the nylon dam solution.
 
 
Even with those little minicel lips the covers fit easily in a small stuff bag, so transport and storage is cake.
 
About the cover material. Poly or nylon? There are advantages and disadvantages to each.
 
Nylon covers need to be originally fitted to the hull in moderate humidity. Nylon stretches when moist and if you install the hull pop rivets in nylon-sagging high humidity the cover will be bear to snap on in dry, low humidity conditions. Nylon covers also sags when rain dampened.
 
The advantage to nylon is that if the cover is hot, desert dry and over taut to install, or if you were maybe a little off positioning one snap (moi?. . . almost never), you can just fill the stuff bag with river water, wait a couple of minutes and then install the damp, easily stretchable cover. If you have some gear above the gunwales wetted nylon will stretch enough to accommodate that protrusion. Cook uses nylon and snaps.
 
Poly doesn’t stretch, or sag when damp. Or damp expand to cover above-gunwale gear. Northwater uses a hook and perimeter line system to hold their covers in place, which allows adjustment latitude with the unstretchable poly.
 
Both Cook and Northwater offer options of elastic bands, bungie or ladder locked webbing straps across the cover, to allow some tightenable play in the material for adjustment with above gunwale loads. I have none of those in my nylon Cook partials and am happy with the clean and simple no-frills design.
 
Other considerations in partial cover design. I allowed some open area behind seat for easy access to day gear. I wanted a space there where I could reach behind the seat to retrieve my camera case, lunch or essential bag without forging blindly under the stern cover.
 
As earlier noted I sometimes use only the bow portion of the cover. I can use the open stern area for above-gunwale gear and it makes it much easier to load or unload half the gear without dealing with the snaps, especially the ones on the far side of the hull. At fugly landings, steep banks or in exposed waves I can extract half of the gear (and weight) before dealing with the covered area.
 
 
Partial covers are all well and good for my purposes. Except in camp. If I have already have that much of the hull covered I wanted to be able to occlude the open seating area as well, so I could leave my all of paddling gear dry and protected inside the canoe, and not have to flip the hull over or sponge out dew or rainwater the next morning.
 
With partial covers in place a simple rectangle third section provides an easy storage cover.
 
 
 
I really like having the ability to walk out to the boat in the morning, undo a couple of snaps and have all my paddling gear already in the canoe, dry and ready to go.
 
Dry, ready to go and hidden from prying eyes and sticky fingers. On a couple of occasions I’ve had things stolen from my canoe at group sites where the boat was beached distant from camp. We once had a local delinquent try to sell us one of our own knives.
 
I think having the hull completely covered removes that visible target of opportunity. If I’m leaving pricy paddles, PFD, rescue knife, compass or sail in the canoe I’d rather have them hidden from sight.