Gene, if you want to see what one of those looks like, I built that exact one last year and your more than welcome to see it. What holds the ridge poles in place is basically your ridge poles are cut just long enough that when put into place they stretch the shanty open. The shanty is always trying to fold shut, but the polls push it open. Basically a friction type of thing that holds them in place. There is also support blocks that you nail to the doors on each side that also act as supports, so that when you place the ridge polls in place, they don't fall out.
Now there is one huge problem with the design. It is way to heavy. Just ask anyone that ever tried pulling mine. Plywood and 2x4's will add up in weight very quickly. Also, when there is snow on the ice, the ski's of which are made of 2x4's don't really cut through the snow very well, even if you try and 45 degree angle the fronts of them to cut a beter path. Basically if the snow is deeper than 4" on the ice, your really hosed due to the shanty tries to plow through the snow, due to the ski's maximum ride height is 4". Now what is cool about this shanty. It is big, it fit perfectly into the back of my Ford Ranger, it was cheaper to build than to buy a new one, BUT I am a firm believer that the lighter the shanty is, the further I am willing to pull it on the ice to go to my fishing spots. I have since retired that shanty to just doing one thing. I take it out to my familys pond, put it on the ice durring the beginning of the season, and never move it until just before ice out. I have since purchase a Shapell 2000 2 man shanty, of which weights about 10lbs. Rides over the snow like a feather in the wind, and it also has loops that you attach to your ice spikes to tack it in.
One more thing that comes to mind, if you decided to follow the directions via the link mousejam provided, the weight of the shanty will definatly be a concern if you are one of those guys that likes to tempt the fate of thin ice. You will fall through if you use this shanty on thin ice.
I know that Johnboy is familiar with making shanties, due to he has made several box style ones that are pretty slick. Maybe he will speak up and give some input on what he has found when building one.
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