So how is that Den looking?
I built a structure in our garden that my growing son could use as a Den. I wrote about its construction in an earlier blog (Part 1 here, and Part 2 just there.) It started as a raised platform with a ladder and scramble board to climb up and a slide to come back down again. I knew as I built it that it would be an ongoing project, to be revisited. The Chap liked his slide. He likes a swing too. So, the next step was clear…
A swing would be suspended below a high horizontal beam, jutting out from the Den somehow. The beam would need to reach out far enough to let the swing be clear of the rest of the structure. In particular, it shouldn’t interfere with the slide or the platform, and it should avoid the adjacent laurel tree. The beam would need to be well braced, to cope with being pulled side to side by the weight of a growing child (and occasional adult). I need to draw a plan.
I wanted the swing to be a part of the den, attached in some way and made in the same style. So I decided the beam and any brace supports should be made from the same treated wooden poles I’d used for the Den’s legs. These poles are heavy, so the braces would have to be strong and substantial. I straight away thought of using these poles to make an A-frame that would hold the beam away from the Den.
To build the swing into the Den I could attach the end of the beam to one of its legs. This was a concern though, as I couldn’t be sure that the two-and-fro of the swing wouldn’t damage the structure – it would rock the leg side to side, pivoting at the foundation. Somehow, I would need to apply some braces to this leg to take the strain and push back against the movement of the swing. Could this be done without affecting the look or integrity of the Den?
I realised that, since I’d decided to build the swing out at about 45 degrees from the Den, I could incorporate braces into the Den walls. From the perspective of the forces that would act on the beam, braces here would stick out against the movement that would be imparted. I decided to give this a go.
So I added braces against the front leg of the Den. One running down the side wall to be embedded in the ground next to the back leg, the other would run across the front of the den and create a new wall part way across the Den’s lower floor. This had the added advantage of making the area a little more ‘secret’; good for future games of hide and seek I thought.
Next came the A-frame. As mentioned, this would be made from two of the long poles set at an angle and crossed at the top. The swing’s beam could then sit over the top of this cross. I began by laying the two poles out flat at the proposed angle, with one on top of the other, and tracing the overlap onto each beam. I then got busy with a saw and chisel to cut out Cross Lap joints in each piece so that the two poles would fit together snuggly. A coach bolt would then hold them securely.
At this time I also chiselled out a curved shape immediately above the joint at the point where the swing’s beam would rest. This would increase the contact between beam and frame and make for a more secure support. I also added a cross-brace half way down the frame to add some strength and stability, and complete the A shape.
As with the legs of the Den itself, I needed to sink the A-frame into the ground and concrete the legs to secure it. With the frame laying on the ground I could mark out where to dig holes before lifting it into place. This time I needed trenches as the legs would go in at an angle. Some messing about with spirit levels and rubble and I had the frame in place and ready for some concrete.
Now the horizontal beam could be put in place. I began by propping it up in the A-frame and against the leg of the Den. Once I got it horizontal I could mark out where the beam would be connected to the leg. I then chiselled away at the leg and beam to allow the two to fit snuggly together so that the leg could take the weight of the beam. The beam was then secured in place with another coach bolt. A couple of hefty screws at the other end would be sufficient to hold the beam in the A-frame.
The beam was quite a lot longer than the gap I’d set between the A-frame and Den. Once in place, its end stuck out from beyond the frame. I contemplated sawing the excess off, but decided to leave it for the time being. I would probably think of something to do with that bit sometime later.
I’m afraid I didn’t make the swing itself. I probably could’ve and should’ve. Anyway, I returned to the garden furniture supplier from where I bought the slide, and found a nice wooden and rope swing to fit in place. This had long bolts that would attach to the beam, with clips to which the swing ropes would hook. I could then adjust the ropes to set the seat at the right height above the ground. I also bought a recycled rubber mat to cover the area below the swing. I’ve often seen swings with a muddy divot underneath where feet scuff the ground. I figured that the mat could better take some abuse, and keep a level surface which would be easier to mow around.
And with that, The Chap would have a few more things he could do in the garden.
There will, of course, be more to come…