Pioneering, in Guiding terms, is the building of practical structures using logs/poles and rope.
The junior version of pioneering is gadget making - creating mini flagpoles, dishwasing racks, bedding racks and the like - practical campsite furniture and fittings.
Pioneering itself is making bridges, gateways, and similar practical-sized constructions, which may be temporary or permanent structures. The same skills are used in each, and gadget making is good practice for starting on pioneering - the same standards of build quality should be demanded for each.
And as we can see, the picture also shows different types of anchorages - for in anything we build, of whatever size, our starting point must be to consider the safety of our construction first - the anchoring of the structure, the stability of it, the strength of the materials, and the load we are expecting it to bear. So, before we can set our sights on a bridge such as this one, we must start by mastering the basics - the knots and lashings for fitting it together, and how to tighten them so that they can really do their job effectively and safely.
The main focus of our learning starts with learning to make three types of lashing. Lashing is the form of knot-work which is used to fasten logs together securely. There are three common lashings used in pioneering - Square Lashing, Tripod Lashing, and Snake Lashing. When making lashings, the most important thing is to be constantly pulling the rope or string tight as you work, to achieve a secure final result.
Square Lashing is used to fasten two sticks or poles at right angles to each other. To begin, fasten your string or rope round one of the poles using a Clove Hitch. Then think of the poles as having four ends. The rope is wound under the first end, over the second, under the third, and over the fourth. Do this three times, pulling the rope tightly as you work. Then wind the rope round under the upper sticks, to pull even more tightly the winding you have already done, then fasten off the rope with another Clove Hitch. You can pull string tight using your hands, for ropes you should wind it round a mallet and use it to provide leverage in tightening the ropes far more effectively than by using your own strength alone.
Tripod Lashing is the most complex to teach of the three, and is used to fasten together three poles, which can then be used as supporting legs for other structures. They can be used as they are (e.g. for supporting a camp bedding rack) but for more sturdy structures would often have cross-pieces attached to hold the legs a set distance apart, using square lashing.
To make the tripod lashing, start by fastening a clove hitch on one of the poles, then wind the rope round the poles three times, drawing it very tightly at each round, and tightening again once the three wraps are completed. Then wind the cord round the gap between two of the poles at one end, then take it down and round under between the next two, then up and between the next two, and so on, still pulling tightly at each turn, until three circuits have been completed, tighten, then fasten off using a clove hitch. The three poles should be so tightly fastened together as a bundle that it seems near-impossible that the ends could be moved apart in any way.
To set it up, move one leg at a time to a diagonal angle, until all three of the legs are in a diagonal position against each other, as shown.
Snake Lashing is often used to create a flattish surface - it is used to fasten a series of sticks or logs onto a frame which has been made. This can be a table top, or the platform surface of a bridge.
To do a snake lashing, take your length of rope or string, and find the middle of it. Use a lark's head knot to fasten it onto the end of the frame. Lift the two ends over the first log (B), then down below and cross them under the frame pole (A). Then lift the two ends over the next log (C), and cross underneath - repeat until all of the logs are fastened onto the frame, then secure the ends at the far end of the frame. Then repeat with the other ends of the logs at the other side of your frame.
Now that you have the basic skills, you want to consider materials. For gadgets, good-quality string and wood the size and thickness of wooden broom handles is fine. But once that is mastered you will want to start on proper pioneering, and that requires rope, and seasoned logs.
'Cordage' is the basis of pioneering. And as with much else, 'the right kit for the job' is key. In the past, 'natural' rope was used - hemp, manila or sisal. They are excellent strong ropes, hold knots well, can be tightened, and can take friction. However they have to be carefully looked after - if damp or wet, they need to be dried out carefully to avoid the risk of mildew or other forms of rotting, and they must be stored in cool dry conditions. Otherwise, rotting can cause damage which is not immediately visible, but which significantly weakens the fibres, possibly dangerously so. They can be whipped or knotted to prevent fraying, and spliced to form joined ropes, or eyelets. Artificial nylon ropes don't have the rot issues, but due to the smooth fibres they can be harder to knot, and aren't so good with friction. The other thing to consider is the type of rope for the purpose. Thick string or fine sisal cord is fine for gadgets, for anything larger, rope should be used. Spars up to 3in diameter will take 3/4 inch line. Above that size use at least 1 - 1.5 inch line. The safe working load of a rope is usually regarded as a ninth of it's calculated breaking strain.
Spars for pioneering are usually up to 12ft, by 4-5 inches butt. Pickets (used for securing larger structures to the ground) should be 3-4 ft. Smaller pieces can be used for ladder rungs, rafts, and gadgets.
Pulley Blocks are more significant investments, but if kept dry, and regularly treated with light oil, will last decades. You would commonly use single or double sheave, and match the size of the block to the size of your rope. Snap links, too, can be used in some circumstances but it is important to use proper mountaineering-type quality, and check the load limits of the one you are considering using.
In addition, a stock of thick sacking should be kept, which must be used whenever any project may be attached to an existing post or a living tree. The old rule about leaving no trace should be at the forefront of the thinking in such cases.
Once you have mastered the basic skills, the next step is to practice using the skills. As with anything else, start at a modest scale - with bedding racks, and washing up stands, where you want them to be well-built and stand up sturdily - but the level of risk from failure of your construction is low, and you can practice using the techniques you have learnt for creating practical designs which solve an actual problem.
Once you have mastered gadgets, it's time to think about larger scale. For this, you must plan the design of your construction before thoughts turn to any sort of building. Plan both the structure you are going to lash, the materials you are going to use - good new rope, sturdy spars with no knots in them - but also the 'anchoring' - how it is going to be secured to the ground and made stable. Any structure which is going to be load bearing has to be able to take double the weight which is going to be asked of it, and be safe.
Then think about the order which it will be best to build it in - what part of it is the basic structure, onto which other elements will be added? At which point should you fit the anchoring? How will you access the structure once it becomes tall, or wide? Design it on paper, work out the steps, think about how to instruct your helpers . . .