Dick...
My personal feeling is to replace the seats. It is a waste of time and resources to try to spot repair.
The fact is the edges of the seat frame are sharp and after yrs of use the material is worn, being cut (more will fail) and looks like hell. Yes the edges will have to be removed carefully (Hitchcock style) and can be affixed one of three ways, just nailed on, just finessed into grooves on either side of the legs or both nailed and finessed into the groves. If nailed on then it will be easy to remove and just make sure to label position and chair they belong to. If in the groove then be very careful removeing and replacing as they can be easily snapped which will really suck as now you will have another repair.
Once you remove those old seats please make sure to round and smooth the edges on the inside of the frame as well as the outside as this will add longevity to the new seat and prevent further cutting of the seat from use in yrs to come. Also make sure the joints are solid as I can guarentee that there is wiggle in those chairs. You want them to be structurally sound before applying the new material.
That is just my feeling as I personally would recommend to replace the seats. The spot repair will stick out like a sore thumb and as more material breaks from use the client may be a bit miffed.
Oh and I did recieve your sample. That is exactly what I have rolls of in different sizes. Granted some rolls have quality control issues as is with any of the materials we have but overall it's identical to what you sent me :-)
Be well and let us know what you decide with these chairs :-)
Katherine :-)
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