I recovered my interior cushions 2 years ago. I was new and a klutz to sewing if you’re likewise these notes may be of some value to you otherwise it may just be overload.
It was a great winter project. I had 8 cushions to recover and it took several months. I set aside a room for the project.
Reading books on the subject were essential to me. I used The Big Book of Boat Canvas by Karen Lipe and Don Casey’s Canvaswork and Sail Repair. Either would have done the job. Lipe’s book was more detailed and step by step.
I use Sunbrella as I wanted it to be bullet proof and hard to soil. As this is a guy-type boat simple and sturdy trumped comfortable and pretty. But that is oversimplified. Sunbrella is made to handle exterior weather and UV so it’s overkill for interior use. It also has a relatively hard and less porous surface. Finally it’s tough stuff so sewing it even on a sturdy machine is a lot more difficult than sewing softer interior fabrics. This is not an issue when you’re sewing two layers but with zippers and corners you’ll be punching thru 4 or more layers. I also found it difficult to adjust bobbin tension with sunbrella. When I later made some cotton cleanliness covers out of canvass sewing was a breeze.
The point of all this is that you really have a wide range of fabrics to consider that will work well besides sunbrella as long as it’s mildew resistant. Both books talk about the pros and cons of various types. There was also an article on fabrics to use in the July ’04 Good Old Boat.
I don’t recall the thread I used only that was a big, commercial spool. I got my stuff from a local recreational fabrics store (Seattle Fabrics) who sell stuff for making tents, sleeping bags, knapsacks etc. They were very helpful on what I would need. Besides a lot of sturdy fabrics to look over they also had all the other stuff to compare like heavy duty zippers, snaps, needles etc. There may be a similar store near you. It would be miles ahead of a regular sewing store. Quilt shops are a good source for miscellaneous tools.
A rotary fabric cutter that looks like a pizza cutter was invaluable. I went thru two blades. Take the warning seriously to keep the blade shield on when not in use. It’s not so much slicing off a piece of your finger but bleeding all over some expensive fabric that’s the problem.
I found a special 2 ft square plastic mat made for using the cutter helpful in minimizing the times I cut thru the dining room tablecloth and into the table.
A seam ripper is also essential as from my inexperience I found myself ripping out and resewing seams fairly frequently until I got the hang of it. I found typically that I’d complete a seam but find out that I’d need to resew it to get a good match on top.
I used my original foam as replacing it was $$$$. Using a seam ripper let me disassemble and use the original covers to make measurements (not templates) for the replacements saving lotsa’ time. Make sure you mark which side is inside and which is out.
Taylor’s chalk, is great for marking where to cut and where to sew.
I put in piping. The stuff I used was plastic and kinda’ stiff. A more flexible core would have been helpful. Also I found the pre-folded bias tape a pain to work with compared to the unfolded tape.
I found that I needed to remeasure and recut the zipper band after the zipper was sewn in. I also had to be careful to keep the zipper on the track to ensure that it would go into the fold.
Hope this is of some help