from my experience karl in a much smaller scale than yours but also in a different aspect,, dovetail jigs rely on the matched cuts between wood and the template bearing surface. if your router is just a smidgen to high or to low, you dont get tight joints. so to me with the amount of use you have given this jig i would say to get another jig or order a new part for it. every time your router runs along the bearing surface or the top surface as well it gets worn, you may not see the shavings come off but it does get thinner or more open.aluminum isnt real hard.. contact porter cable company and ask them for there veiws.
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