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January 16, 2006

Portcullis Gateway

As you can see, this gateway has a movable gate that is used to open and close it. This gateway was designed by Kudus patrol and tested at our troop camp in June of 2005.

The equipment you will need for this:
2 x 4m poles (lightweight)
3 x 2m/3m laths
2 x long stakes for anchoring upright poles
6 x lashing ropes for frame
2 x sash pulleys/ keyrings / carabiners
nylon lacing cord

We are building a simple gateway, suitable for a patrol in camp or possibly for a troop on a weekend camp. What makes this gateway unusual is the mechanism for opening and closing the gate, which rises straight up like a portcullis in a castle.

The outer frame is made first, by square lashing the crossbar onto the two vertical spars. Once those 2 lashings are tied, lie the gate down where you want to place it, and hammer the stakes vertically in at the base of each pole- if you do it this way, you know you will have the right spacing for your stakes. While the stakes are being hammered in, you can work on attaching the gate to the gateway.

The gate is made by tying one lath under the other, using short pieces of sisal (if you have a scout group that recycles sisal you might have a number of short pieces of sisal).

To attach the gate to the gateway: in the top corners of the frame, you need to tie in the sash pulleys (first prize), carabiners (second prize) or keyrings (best effort) to run the cord through. Looking at the diagram, you will see that 2 cords are tied to the gate, then run up to the pulleys: the turquoise one runs up into the pulley and then across to the second pulley, while the red one runs straight up into that pulley and then down. Tying the red and turquoise ropes together with a stopper knot will stop the gate at the correct height.

Once you have attached the gate to the gateway, you can raise the gateway up and while your assistants holde the gateway up, you need to sheer lash the upright poles to the stake. Providing you are using long stakes (+- 1.2m or 4 feet) you will be able to have the gateway without any guylines. If the ground is very soft or your stakes or short, you may need to guy the frame.

Allow 3 hours for an inexperienceed patrol to build this gateway.

1 comment:

Anonymous said...

what if there is no one inside the campsite to man the gate, wont it be very inconvenient?