A couple lessons learned creating these props... If you are going to make them big, use larger diameter pipes for several reasons.
First, oversized masks, the clothing, stuffing and sheer length of the frame will cause them to bow using anything smaller than 1=1/4 pipe. There is a limitation of standing the props in full upright position.
Second, I don't like to glue any joint unless I have to. The larger diameter pipe gives more surface area to create friction inside the joints. What this means is, if you aren't going to glue the parts, there is a greater chance your position of arms and legs will hold without gluing them.
Third, use a pipe reducer to reduce the size of the pipe where the hands connect. I use coat hanger wire inside the gloves to create positional hands. In the case of the troll, it was very difficult to get the hand to stay in place using a 2" pipe at the wrist, a lot of stuffing and duct tape was used to tighten the hole up enough to hold the hand in place.
Fourth, screwing an end cap into a piece of wood may be enough to secure a very light weight prop but the higher you go and the more weight you put on it, the more leverage the prop has to pull the screw loose or bust the endcaps. I used lag bolts in the Troll with 2" pipe and even they weren't strong enough to keep the prop from leaning forward and backward and falling over. Use pipe flanges instead, see picture of the flange under the boot. this gives you a wider area to screw down and reduces the amount of leverage the prop has in pulling the screws out or busting the pipes joint at the base, they are about $4.50 a piece but are worth it if you want your prop to stay upright as they are made to take the stress: