Step 1: Cut PVC to desired length. Please note that anything over 46" is going to be hard to make safe because the weapon will have a tendicy to whip a alot.
Step 2:The pipe foam is cut next. The foam is cut to be slightly longer than the lenghth of the PVC which will be your blade. The foam is then slid over the PVC leaving an overhang of one inch at the top of the blade. This one inch hole is filled in with scrap open cell foam packed semi-tightly.
Step 3:A 2-inch square piece of open cell foam is then cut for the thrusting tip.
Step 4:The Duct Tape is laid sticky-side up on a table. Once done, the sword is placed on the tape allowing 1-1 1/2" to overhang at the bottom of the blade. After the sword has been properly placed on the tape, the 2-inch square foam tip is gently pressed against the top of the sword blade and then against the tape. The tape is then unrolled and laid on the top of the sword. The tape is cut to allow 1-1 1/2" to overhang the bottom of the sword. The tape is then pressed gently against the pipe foam without causing wrinkles in the tape. The two overhangs are pressed against the PVC to hold the pipe foam in place. The tape should not overlap on the blade. There should only be one layer of tape on the blade.
Step 5:The process of unrolling the tape, placing the sword, unrolling more tape, and placing it on the sword is repeated for the other open sides. At this point the sword blade should be complete and no pipe foam should be visible. Make sure your stabbing tip has a few slits cut into it so it can compress easier.
Step 6:The crosspiece is added next. It is made with pipe foam. Once the size of the crosspiece is chosen, the pipe foam should be compacted to remove the hole along its length. Duct Tape is used to hold the ends closed once it has been compacted. A hole is then cut in the middle to allow it to slide onto the bottom of the sword.
Step 7:Once on the sword, the crosspiece is taped with electrical tape to hold it to the bottom of the blade as well as to the PVC. When it is completed, no pipe foam is visible.
Step 8: (optional: only require for blackjack skill.)After the crosspiece comes the waylay. A 2-inch piece of pipe foam is placed on the bottom of the sword allowing 1 inch to hang over the bottom of the sword. The 1-inch hole on the bottom is filled in with open cell foam in the same manner as the hole on the top. Then a piece of cell foam about two inches in size (same as stabbing tip is fastened to the bottem, with two pieces of duct tape going over it. Make sure to make a few slits in the waylay tip so that it compresses better.
Thats pretty much it in a nutshell. If you need supplies go to http://www.larpware.com