JD, There are many jigs for making box joints. Yes, you could build this jig at home out of HDPE but I think it will cost you more than $5, after all your time is worth something. This jig is from The Router Workshop. It performs better than any other jig I have tried. The reason this thread is a sticky is because of the modification; cutting the openings for the Vac-U-plate system. This patented system installs under the mounting plate and does a very good job collecting most of the dust and swarf generated by routing. There is the added advantage that you are not fighting a dust collection hose over the table. The entire Router Workshop table seems very spartan when you first look at it. It is a well designed table with many accessories that install in seconds so you can spend your time routing instead of doing complicated set ups. I am a convert to this "Simple is better" approach to routing. If you have not seen the show, you can view The Router Workshop on
www.thewoodworkingchannel.com