The ever evolving Den
I’ve been writing about a play-fort or Den I built for my son. It began as a platform with a slide and a ladder. In Part 3 of the story I had added a swing. This was formed from a long beam suspended between the Den and an A-Frame. The swing needed to be hung at a distance from the Den to reduce the risk of it bumping into someone or something. That meant that there was a gap between the swing and Den that looked like it could accommodate something useful. Also, the beam was long enough to extend some way beyond the A-frame, again, offering the opportunity to add something extra.
I have to admit, I took the easy way out in both places… I bought things, rather than making them myself.
First of all, for the gap between the swing and the Den, I wondered if there was room for a new way of climbing from the ground to the platform, or of sliding back down again. I spent some time searching for a fireman’s pole, but these all seemed to be a little pricey, and I couldn’t find one at the time that was a suitable height for the platform and beam.
Then I spotted a Scramble Net. This was made of a heavy duty rope, was a little longer than the gap between the ground and the beam and was about the width of the gap between swing and Den. The net was basically just a rectangular grid of rope, with no securing mechanisms. So, I would need to figure out how to attach it, but I was sure I could figure out something appropriate.
I figured out the net was just about long enough to wrap right around the beam and then stretch to the ground at a slight angle. I fashioned a series of hooks using coach bolts that have their heads sticking a few inches above the top of the beam. Then wrapped the net once around the beam and hooked the net’s top edge over the bolts. Pulling down on the net pulled it into the beam and bedded the top rope into the bolts. The weight of the net plus climber pulled the net tight around the beam making it unlikely that it would come unhooked. To make doubly sure, I wrapped a section of rope around the beam a few times to tie the whole lot together. This doesn’t come out very clearly in pictures, so here’s a sketch:
I then fashioned a set of pegs to secure the net into the ground. The pegs were made from 50cm long steel rods that I bent around a piece of scaffolding to form U-shapes. These would trap the bottom of the rope net and hold it in place. I was trusting a little that the rope would survive the weathering and possible rot from the ground.
For the overhanging section of the beam, I have regularly checked the strength of this by jumping up and hanging off the end. I’m a big, heavy bloke, and it takes my weight ok, so I thought I would be safe to add something here. Quite by chance, at a Country Show, I came across a company selling garden furniture. They had a Trapeze Bar for sale, which comprised a wooden bar with a pair of gym rings below that could be used for climbing and acrobatics.
I liked the look of this because it wasn’t just a swing. It looked like it would be used for climbing up and down more than for swinging side to side. Since the beam extended out beyond the A-frame and was unsupported on one side, I was worried that a full-on swing would put stress on the frame and Den. This looked a little more sedate for that position.
So there we had a wider array of things to do on the Den.
Unfortunately, as soon as things are built outdoors, nature begins to take its toll. I inspect the various pieces regularly, checking for loose fittings, movement and signs of rot or damage to the wood. Last spring, I spotted that the A-frame had an ever-so slight movement when The Chap was on the swing. Close inspection of one of the legs revealed that it was being attacked by wood lice. It had a hollow sound when tapped, and points where I could move the wood just by applying pressure with my fingers. Oh dear.
I dug out the turf around the leg and dug down to the foundations. Just below the line of the soil, the leg had been half eaten away.
First step was to insert a prop to take the weight of the swing. Then I could properly dig out and remove the rotten wood, and decide what to do to fix it. I began by cutting out the rotten section up the leg until I reached good solid wood. My plan was to attach a new section to this leg and then re-secure the foot where the old had been.
I dug down to the foundations, removing as much of this as I could to expose the bottom end of the leg. I could see that the wood was fine and solid once inside the concrete, so I chiselled some of the concrete away to expose as much of this good section as I could manage. My new section could then be bolted to this secure foot, and new post-fix concrete poured around the assembly to set it in stone.
I sourced a short section of pole that could replace the rotten section. Then I began the task of shaping this to match the two ends in which it would sit. First I figured out a way of tracing the shape of the wood that was still underground. This required some imagination and a little bit of moulding just to build a picture of what was there.
I then gradually worked on the stump, and on the new section of pole until I had a join that I felt I could rely on, and through which I could fix a coach bolt to bind the two together. Lots of chiselling and fillering and measuring and propping up and checking for bumps and hollows. I guess this must be how a dentist feels when working on the root of a tooth! Eventually I had a shape that would let me attach the new section nice and securely, in line with the rest of the leg.
It’s not easy getting pictures half a metre underground… Anyway, with the awkward lower section figured out, I could move on to fashion a lap joint to secure the top of my new piece to the main part of the leg.
I gave every possible surface several thorough coatings of Wood Preserver, then with a handful of coach bolts, secured the new piece into the frame. I chose stainless steel bolts over nickel-plated so that I could cut off the protruding threads and still get a weather-proof finish.
To finish off, I poured new post-fix concrete into the hole, covering the lower join and cementing as much of the new piece into the foundation as possible. Then, in a change from the previous design, I put a ring of gravel around the leg up to the surface, rather than soil and turf. My hope is that this will reduce the contact of soil to the leg, improve the drainage around the wood and lower the probability of bugs finding a nice place to live.
Looking at it today, the Den all seems to hold together quite nicely.