HEY GET THIS-
Try using the white liquid tufo tire sealer that works like slime, it's a helluva lot easier than fixing them and if if it won't seal the hole you probably will have cut/damaged cords anyway. I've salvaged tires I had laying around for years that I didn't want to fix (I hate doing it) and it's sealed flats while I was riding too!!, bad thing is- you need to use tires with removable valves and it won't work for latex tubes, only butyl but...
I now have a pressurized can of sealer made by Vittoria, that blows up the tire (with the valve in place) when you get a flat as well as sealing it and works for latex tubes. I haven't used it yet, my local most trusted expert Steve Loveland says it does work, and you don' tneed to remove the valve (
www.twowheeltransit.com - if you can't find it)