Laser Reaming

Sometimes I like to bounce new ideas off of students. Sometimes I get a blank stare or "yea, that's cool", but yesterday after showing Pete Wiens how to drill and ream his stool seat with sight lines and mirrors it hit me that I needed something different. The problem is getting someone who isn't use to looking at sight lines and bevel guages to ream at the proper geometry to get all the legs really close to what they should be. Up til now "really close" was the best I could hope for. All I said to Pete was "what if we had lasers?", and today we have what you see below. With this set up anyone can ream the tapered holes for the legs spot on. It gives the students more confidence than I could ever imagine and it really sets up in seconds. If it were not simple then believe me, I would not fool with it.
It works like this. Go to the local home improvement store and pick up two cheap $15 B&D line lasers. They have a small magnet on the bottom. We built the base out of scrap wood with a heavy hardwood bottom for stability. It's good to have rubber glued under the base so they won't slide around on the bench. The dowel makes it adjustable for easy setup. The laser sits magnetized on a metal nut imbedded in the base.

Now on the bottom of your seat blank after you have drilled the straight holes from above the usual way, draw a perpindicular line across the hole to the sight line. Set up one of the lasers tilted to the drilling angle and sighting down the perpindicular line. The other laser will be adjusted to 90 degrees to the seeat blank and sighting straight down the sight line. Stay with me now.

Now all you have to do is start reaming keeping the crosshair of the lasers right on the top point of the reamer. That's it! It comes out perfect and I have not found a flaw yet.

A couple things to remember. Never look directly into a laser. This set up with this brand of lasers keeps the line of light lower than eye level. Also it helps to turn off the lights above your workbench. I have windows all around and still had no problem seeing the laser lines. Also turn the top of your tapered reamer slightly concave so the laser will fill in to the top of the reamer. I hope this will shead some light on reaming perfect angles. Good luck.