I get asked a lot about ironing patches onto bags.
So I did what I've learned to do in my old age, I asked a professional.
Walter of Falls Creek Outfitters is the guy who makes patches for just about everyone.
If you want custom patches, call Walter, the nicest guy in town.
Anyway, this is what he said.
The best way to iron on patches. Is 2 clean the Garment make sure there's no lint. As the first obvious step, next place the patch where you want it and place a thin bandana or a washcloth over top of the patch. If you're using a household iron put it on the highest setting with no water and no Steam. Next, push down on the patch with the iron and hold for about 45 seconds to a minute. Closer to a minute probably. Once you lift up the bandana, washcloth, or (ideally) heat transfer paper. lift up and check the edges of the patch. Make sure that they are fixed in place and secure.
The next step is very important to. If you can flip the Garment inside out and apply the same pressure on the back side for about 45 seconds. It helps draw the heat seal chemical through the fabric and helps adhere better to the garment.
Hope that helps!
-Ely Ruth Rodriguez