This is the plastic welder that I use and where I got it from Urethane Supply 5600HT Model 6 Airless Plastic Welder - eBay (item 350442137880 end time Mar-24-11 07:31:54 PDT)
After a year or so of borrowing one from another member I finally caved and bought one. It works great. Just follow the directions and you will be doing good welds in no time. It's just a little over the price range you were looking at, but it seems to be a quality tool so adding it to your arsenal will only help you down the road. the kit comes with some welding rod for every type of plastic you can imagine, but you will want to get some more poly rod for the argo's. here is the best source I've found for that. 1/8" HDPE Welding Rod | U.S. Plastic Corp. it would be great to find rod that matches the body color, but I've found that the raw (white-ish/ clear-ish) rod works the best and makes the strongest welds
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