This is a perfect example of trash to treasure - this worn, broken chair was unusable and about to be picked up by sanitation before I saved it. It had great bones and I knew it had many more years of use ahead of it, so I accepted the challenge and took it home!
Step 1: Remove the Offending Damaged Leather!
After acquiring this fabulous chair from a neighbor who was just going to throw it out, the first thing I did was remove all of the broken leather straps and clean the chair thoroughly...first using an old soapy sponge, then disinfectant wipes, then using a wood polish oil to nourish the wood a bit and return it to its natural sheen. We don't realize how dirty chairs get, with splatters of spilled stuff all over the legs, etc...so after a good clean and polish, it was already looking better!
Step 2: Buy Replacement Straps and Prepare Then for Attachment!
I couldn't afford to replace the straps with new leather...but I found these nice dark green nylon straps at a sporting goods store and bought enough to replace all 20 of the straps - 6 (vertical) and 2 (horizontal) for the top section and 12 for the square seat. I measured each strap so that it went over the top of the frame and would be attached underneath with a staple gun. Obviously the vertical ones on the top sections were smaller then all the others. After I cut all of my straps, I had to bun the edges so that they wouldn't fray and could be secure with no slipping/falling apart once attached to the frame. Don't do this unsupervised if you are a child! :) Also a good idea to be near a sink or have a fire extinguisher nearby... Carefully use a lighter to each end, let it burn for a second along the cut edge (if it lights into a little flame, then just blow it out into the sink - be sure not to have flammable materials around you) to make sure each end is well cauterized all along the tip. Let it cool a bit before handling.
Step 3: Learn What a Plain Weave Looks Like and Replicate!
After all the straps are ready, it is time to attach them to your (naked) chair frame. I have attached a picture of the plain weave pattern you should follow. It's best to put all the straps in one direction first, then attach the ones in the opposite direction, leaving equal spacing between each strap, weaving over and under each affixed strap to recreate the basic weave pattern. Make sure, as I mentioned in the previous step, you are attaching them under the frame by FIRST looping the strap OVER the frame from the inside out - see the picture of me stapling onto the upside down frame. Pull them as taught as you can before stapling, they will loosen a bit with time, so need to be as taught as possible now. I used my trusted Stanley Pro Sharp Shooter TR200 for this project, but you can use any staple gun with stapes that are at least 3/8" deep to bite into the frame and support the straps. If you have an electric staple gun, even better!
Step 4: It's Finished! Enjoy :)
Double check that all the staples went through ok...and remove/replace any that look like they bent when going into the wood (sometimes that happens). But when you are confident each end of each strap is well attached, you are DONE!
Place it in your home, or give to to a friend, and enjoy. Be glad you fixed this chair and saved it from the dump to give it a new life :-)