You do not need a tri-bolt to hold the legs together.
Take a look at this walking stick that converts to a three legged stool.
http://www.sustainla...XCSBWY2DIMHVO3A
They use a metal ring like Big Daddy does on his plans. The metal ring keeps the legs from separating and the angle of the legs across the ring distributes the persons weight down the leg.
Hope this makes sense. If not let me know and I will explain it better.
Also do some searching on here and you will find a person named UKRay that makes the tri-bolts for sale. He is out of England so take that into consideration when thinking about having the bolts shipped to you.
His WEb site is www.barefootleather.co.uk
Ray K.