»  Treehouse — Phase 5

 

In Phase 5 I add the finishing touches to the treehouse: the rope ladder, a power point, and some extra security reinforcement.

Rope ladder from below The rope ladder gave me a lot of trouble.

In the first place, if you look back at the first picture in Phase 2, you will see that I planned to hang the rope ladder from two eye bolts at the south side of the trapdoor opening. This is one of those things (ask any engineer) that looks fine in theory but is a disaster in practice. If you actually try to climb up a rope ladder fixed this way, you face an unseemly and dangerous scramble to hoist yourself in at the top. I therefore did a bit of fast re-design, moving the eye bolts to the ceiling of the tree house (with some appropriate bracing up there), then hanging the ladder straight down, so that you can climb up until you only need step off onto the floor.

Then there is the problem of mooring. A free-hanging rope ladder is more difficult to climb than one that is firmly moored at the bottom. I sort of knew this, but had put off thinking it through.

Then there is the actual structure of the rope ladder. I took the straightforward approach of scrutinizing the rope ladders in local jungle gyms, and copying their construction. None of them was anything like as long as mine, though. I used thicker rope than any of them — ½-inch three strand polyester/polypropylene. This meant I needed thicker rungs, since the favored method of construction seems to be just drilling holes through the ends of the rungs, threading the rope through, and binding with a round turn. So I used the thickest (and best-quality) doweling I could get, which was 1½ inches. Unfortunately, while I am fine with it, this is a bit much for 8-year-old hands to get a purchase on. (It is also untreated wood, so will need careful watching.)

So all in all, I am not very happy with my rope ladder, and may do a total redesign. But here it is as it exists at present.
Here you see how the rope ladder just goes straight up inside the tree house … Rope ladder, trapdoor open
Rope ladder ceiling fixture … to the ceiling, whither I have moved the eye bolts. (Note that there is a corresponding cross-brace on the roof, resting on the roof beams at each side.)

The rather lengthy splice — seven tucks — is recommended for poly rope. Like a good sailor, I tried whipping the loose ends; but either I have the wrong kind of whipping twine, or else poly rope won't take whipping, I don't know. I am getting some advice on this. I hate to leave splices un-whipped. Same with the other ends of the ropes, at the bottom of the ladder. They are currently "whipped" with duct tape …
The trapdoor can be — and, as I keep telling the kids, should be — closed when not actually being entered or exited through. This can be done without moving the ladder.

The trapdoor is nothing much: sheet of ply, 2×4s nailed to the underside, hinges, ring pull. (The last helpfully sold at Home Depot under the name "trapdoor handle.")
Rope ladder, trapdoor closed
Rope ladder stowed Alternatively, the rope ladder can be pulled right up into the tree house and stowed on the ceiling. There are two hooks there you can hang it on.

This is totally the favorite feature of the ladder so far as the boys are concerned. It means nobody can get at them. I have had to make a rule that the ladder must be lowered on command of an adult.

This is so much the boys' favorite feature that they leave the bottom of the ladder un-moored, gladly putting up with the extra difficulty of climbing an un-moored ladder for the privilege of being able to pull the ladder up behind them and scoff at the world below.

(And as a matter of fact, the extra difficulty is not so great for the kids. Their weight is much less than mine, so the un-moored rope ladder departs from the vertical much less when they climb it than it does for me. They don't seem to mind at all.)
The mooring at the foot of the ladder is just two doggy stakes screwed into the ground, secured with spring clips to the penultimate rung.

This rather spoiled my idea that the foot of the ladder should be surrounded by nothing but soft peaty soil covered with loose wood fragments, so that if anyone should fall, there will at worst be a broken collarbone. The kids now have the additional opportunity to cut open their heads on a doggy stake.

I'll try to think of something better here. And anyway, as I said, they prefer not to moor the ladder, so they can pull it up after them. I may just abandon the whole mooring thing. [Added later: I did. The rope hangs free.]
Rope ladder moored
Y-brace, from south Time now to get rid of that rope that has been acting as insurance against the "Y" supports slipping out. If they were to slip out now, I'd be in a world of hurt. So let's do something.

Here's what I did: braced the "Y" supports with some cross pieces of spare 2×4, bolted through at each end. Not bolted through the "Y" supports: the only compromise against the integrity of the "Y" supports is a single 3-inch galvanized nail through each, so the brace can't slip down. You can just about make out the head of the nail in the west support (on the left).
Question from reader: In all this woodworking, have I ever hit my thumb with a hammer?

Oh yeah. As my old Dad used to say: That's why they call it a "nail" …

(Commented a different reader, after seeing this picture: "You'll want to put some ice on that …")
Thumb
Power receptacle All right, perhaps I'm getting a wee bit carried away here, but there might as well be a power receptacle in the tree house.

Said Danny, on seeing me fix this: "Oh, good. Now I can bring my computer up here and play games!" No–o–o–o–o–o … (I think he was kidding.)
The power line comes from a secondary box in the garage. I just threw the line up into the tree, then let it down at back of the tree house. You can see it coming out from under the eaves of the garage and disappearing up into the tree.

This is sturdy outdoor-use No. 12 line, with a jacket you pretty much need a blow torch to cut through. Still, friction with the moving branches where it hangs on them is going to wear through the jacket eventually, so this is a temporary expedient for the Memorial Day grand opening.
Power line
Completed treehouse, from west Just one more thing the tree house needs for its Memorial Day grand opening: Old Glory (and a bracket system to hold her in).

I knocked together two brackets with some spare pieces of wood, and bolted them through the wall to a 2×4 on the inside.

The tree house is now complete.



End of Phase 5.



Continue to Phase 6.