When ever a precision cutting action needs to be made I try not to rely on model craftsmanship alone.  Instead, I take the time to build a special jig to help me make those precise cuts, and in the long run, save time. I recently decided to build some rocket designs from my youth. The first one being the Star Ship Excaliber. I needed to cut a couple BT-5 body tubes in half down their entire length.  Now I could of drawn two parallel lines down opposite sides of the tube, gotten out an Exacto knife, and started cutting, but instead I built a simple jig to do it for me.  Power tools, I can't live without them. The more tools you've got the better. My Band Saw is the most used power tool in my shop.

The jig presented here can be made in about ten minutes with scrap material found in your woodbin.  The jig can also be scaled up or down depending on the tube size that needs to be cut. The following wood sizes were used for my BT-5 body tube jig.  Two pieces of 3/8" square balsa 5 1/2" long. One piece of 1/8" Plywood 2" x 5 1/2". One small piece of 1/32" plywood, measuring 5/8" x 1 1/4".  None of these wood sizes are critical except for the 1/32" plywood since it's just about a perfect-match to the saw blades cutting width. The construction of the jig starts by first gluing one of the 5/8" square balsa sticks on top and along of the right side of the 1/8" plywood.  Place a piece of BT-5 body on top of the 1/8" plywood and to the left of the 3/8" balsa stick. Using the body tube as a spacer, glue the second 3/8" stick to the left of the body tube. Measure the distance between the two sticks and place a mark right in the middle.  Line up your band saw fence so the blade will cut right down the center of this mark.  Make this cut 5/8" long.  Round the edges of the front end of the 1/32" plywood with a piece of sandpaper. This will help the body tube to pass on either side of the Plywood during the cutting process. Glue the 1/32" plywood piece into place making sure it lines up with the end of the 1/8" plywood and is at a 90-degree angle to the base of the jig. The only thing left to do is to cut a slot through the right side of the jig about 1/4" in front of the 1/32" plywood to except the band saw blade. I like to use 1/8" wide blades for cutting my tubing since the cut out in the jig will be smaller.  Adjust the band saw fence so the cutting blade lines up with the 1/32" vertical piece of plywood and start cutting your tubes.  To use the jig I hold the jig against the fence with my left hand and push the body tube trough with my right hand.

Close Up of Tube Cutting Jig

Tube Being Cut