Here is a simple sun shade I made using ideas I've seen on postings here. No welding, just some screwing, bending and drilling.
The angle I wanted for the sun shade coming off the rocket launchers was 112 degrees. I found that the a chrome fitting (which is normally used as the short "bow fitting" where the side railings join) is an angle of 110 degrees so I ordered two or them. Lucky find. After I had them I ordered stainless tubing to run a piece into the rocket launcher and another piece to run back over the aft deck about 4 feet. The three cross members are aluminum since not much load on them. The cross members go into standard chrome rail fittings on the stainless tubes.
Then I bought a piece of PVC pipe with the largest diameter to fit into the rocket launcher and another smaller diameter piece to go inside it. They bottom out into the stopper at the bottom of the rocket launcher. Then I used a few wraps of good tape to make the PVC pieces fit into the rocket launchers quite tight and the stainless post was the last to go into the center of it all. I drilled a hole through the rocket launcher and all the inserts to hold it all in place and to keep it from twisting (probably not necessary).
I bent some arch to the three cross members so water would drain off. Two are hidden under the Velcro strips on the Sunbrella so only the middle one shows my amateur bending ability.
When I assembled it, I did have to drill holes and use stainless screws on the two "bow fitting" pieces as the allen set screws were simply too weak.
After I had the frame assembled, I took it to a local canvas shop and gave them the piece of Sunbrella I had purchased from EBay. They sewed it all up and put wide velcro straps all abound the perimeter of the sun shade. Took it back to the boat and popped it into the rocket launchers. It could come all apart easily if i wanted it to but we like it up. I could also loosen the chrome fittings holding the center and back cross members and slide the entire shade forward towards the rocket launchers.
There can be a tendency to grab onto to the sun shade as one boards the boat, but the stainless is quite strong and even if something did bend out of shape, I could probably straighten it or simply make another piece as I had tubing left over....................Pete