Review on 🔩 Woodworking Pieces: Tongue Milling by FivePears by Jason Ballard

These bits come with extra washers so you can insert them into the gap between two cutting tools. I ended up using 5 of the 6 washers that came with the kit for a perfect connection. 4 washers were installed out of the box and 2 extra in the package. With 4 washers the connection was too tight so adding a 5th washer was just perfect. Matching the tongue and groove is difficult. Take your time, test it out on scrap wood and you can definitely make a nice tight bond without spending a ton of money. I only use a 1/2" shank for bits this size. So if the 1/4" collar is on your router, either get a 1/2" collar for your router or upgrade your router. Do not buy the 1" shank /4 inch version.