Building a Climbing Wall

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A post shared by Denis Drescher (@telofy) on Sep 2, 2020 at 8:03am PDT

Design

First, I ordered the T-nuts. They take about 1–2 months to arrive, are almost certainly needed, and are not a great sunk cost even if I decide not to go ahead with the board. I felt like I was 60% likely to go ahead with the climbing board plans, and in this majority of worlds, I didn’t want to be blocked on an order later on.

Then I started designing different wall concepts, watched YouTube videos on home climbing walls, and read tutorials on the topic.

I came up with about four designs, detailed below.

Preferred Design – 3 Modules of 1 Meter

Use Cases

1. It should be suitable for using inside my room, at least most of the time.
   1. I’ve achieved this.
2. It needs to be easy to take apart to take outside for a day or for moving flats. Each part should easily fit through doors and be less than 40 kg, ideally less than 30 kg.
   1. They’re about 32 kg.
3. It should be extensible for adjustment for flats with higher ceiling.
   1. It is.
4. It should rest at an angle of ~ 0–45°, i.e. vertical, diagonal, or anything in between. The climbable side is the one facing downwards.
   1. The angle is 48–49° off the vertical.
5. Ideally, this angle should be flexible.
   1. It would take a lot of work, but in a larger room, I could angle it differently.
6. The budget is < CHF 500 excluding climbing holds.
   1. It was about CHF 420 without holds.
7. Assembly should not require any power tools beyond a drill because we don’t have those.
   1. Check.
8. It should not require drilling of any holes in the apartment walls, floor, or ceiling.
   1. No walls or ceilings have been drilled into in the making of this wall.
9. It should be positioned such that I can use my 2 m x 1.6 m bed as a mat.
   1. Check.

Measures

1. The beams are 100 x 8 x 8 cm. (The model below currently shows 100 x 8 x 6 cm – I’d need to update that but realistically never will.) Each module has two beams on each side, four in total.
2. The boards are 200 x 50 x 2 cm. Each module has two boards that are firmly screwed to the beams with ~ 12–14 wood screws per 50 cm.
3. My ceiling is at 240 cm. The board reaches almost all the way up to it.
   1. Various slight error added up to a few wasted cm.
4. The board rests at a ~ 47° angle, a bit more overhanging than I had hoped but it’s fine. (To decrease the angle without it going through my ceiling, I would have to make it shorter. But I can’t make it shorter or it would have to go through my bed instead. I also don’t want to make it shorter than ~ 3 m.)
   1. It ended up at an angle 48–49° off the vertical.
5. The kick board at the bottom is ~ 25 cm high.
   1. I decided to skip the kick board. It would’ve been hard to reach anyway because my bed is so high.

3-D Model

The wood is all one shade. I’m using different shades in the model to distinguish the modules that can be taken apart easily from all the little pieces that are firmly attached to each other.

The 1 m beams are connected to each other with two metal bolts and by having their ends rest against each other. If this is insufficient, I can wrap a metal band around each end to keep it from splitting.

The boards have each three rows of holes for the T nuts. Every other row is offset by half a hole distance, which, I hope, improves stability and maybe also flexibility for the boulder problems.

I want to place a lamp roughly where the camera is to improve the lighting.

The whole climbing board is in my room. The “feet” of the kick board press against one wall (I’ll put something soft there to protect the wall from damage) and the top rests in the corner between the opposite wall and the ceiling. I’ll put a blanket there to protect the wall from the board and from my shoes if they hit the wall during a climb.

The whole board is flush against one side wall of the room. I’ll put some foam or a blanket there as well to protect the wall.

Anticipated Problems

1. A single 350 x 8 x 8 cm beam would deform only ~ 1 cm in the middle even when I do dynamic exercises on it. That would be unproblematic for climbing but it may loosen the outer ones of the screws that hold the boards. The modular design will probably lead to more bending at the joints, and I can avoid putting screws between beam joints and the edges of the boards. Still, I want to anticipate this problem better.
   1. One idea is to put double-sided adhesive tape between the boards and the beams. I’ll probably do that anyway to facilitate the assembly. The tape is about 1 mm thick. Over 50 cm, the beam may not deform very much. ~ 1 mm or a bit less of that can be absorbed by the tape. There’ll be a bit of room there anyway because of the backs of the T nuts. I’ll try to avoid having T nuts press against the beams in the middle of the boards.
   2. I might put rubber under the heads of the screws that hold the boards. That might add another ~ 0.5 mm of tolerance before the screws start to suffer.
   3. The boards themselves are probably also somewhat flexible.
2. I haven’t decided how I want to connect the board proper to the beams that emanate from the kick board. If I use only one bolt there, I’m worried that it’ll break off the kick board and fold upward.
   1. I could prevent that by placing something heavy on these beams.
   2. I could put a 90° angled metal piece where the beams meet to keep them in place. That would make the bottom piece harder to take apart.
   3. I could also saw pieces out of the beams to fit them into each other. But I’d like to avoid that since I’d have to do it with a hand saw and a chisel, and it seems like a lot of work.
   4. I could rethink the whole bottom section.
3. The board might suffer some parallel deformation, i.e. deformation along a horizontal axis. The boards should prevent that, but maybe the screws aren’t strong enough for that.
   1. I don’t think this is likely to be a problem, but if it does become a problem, I can put an X of ropes across the back of the board. If that’s not enough, I can put an X of beams across the back of the board.

I ended up addressing none of these either because the risk seemed low or because I can address them as they arise.

Discarded Designs

6 Modules of 50 cm

The idea here was to have particularly small, light, and interchangeable modules. They are all identical but fit together because the beams are angled just right over the 50 cm for the next beam to fit next to them. I’ve discarded this design because of doubts about the stability of the connections of the beams.

Multi-Angle Wall

Another way of getting a longer wall into my small room was to have, say, four modules at angles 0°, 20°, 45°, and 90° or so in that order one after another. They’d form a bent wall to the ceiling and then along the ceiling. It would’ve enabled me to train on various angles of walls. But I couldn’t think of a way to make it flexible enough for moving and adjusting to other room heights.

Hanging Wall

In this idea the modules were connected by ropes rather than beams. At the top, the ropes go through a hole into the board from the front to the back where there’s a knot. Then they continue behind the board to the bottom. Below the board there’s a gap where they thread back to the front, and then go back through a hole in the top of the next board. And so on.

Downward pressure on protruding holds on the lower half of the board results in a downward and inward (into the board) force. But also in a tautening of the rope. The rope then keeps the board from tilting forward from the inward force.

The problem is of course that this only works for forces on the lower half of the board, so I’d have to use rather many boards to be able to place the holds at a sensible distance. And despite all the tautening, it still seemed like a rather shaky contraption.

Furthermore, I can’t think of a way to hang it in my room without drilling holes.

Process

1. Order T-nuts.
2. Come up with different designs. About four in my case.
3. Get inspiration online.
4. 3-D-model the designs. I used first Vectary and then Blender for this.
5. Describe designs and ask around for feedback on them.
6. Rearrange furniture.
7. Order materials and tools.
8. Wait. Wait a lot. Wait long and hard.
9. Once the materials arrive, put it all together.

Problems

1. The beams are connected with 1 cm x 20 cm metal bolts. The plan was to use wingnuts on some of these to enable easy attaching and detaching. This failed because (1) the bolts are very hard to get into the holes even though they are also 1 cm and (2) my room is too small to put the wall horizontally on the floor, so that there is always weight on the bolts.
2. Using continuous beams would’ve sacrificed the modularity but made the building process somewhat easier (or greatly easier had the room been 20 cm longer). It would’ve also made the wall 10–20% lighter.
3. It would’ve been useful to determine the point where the beams touch their shoes experimentally. I call “shoes” the beams that I put on the ground and that the ends of the 49° beams are grounded in. My 3-D model was off by 2–3 cm due to all sorts of small modifications that I made later. That created some extra work.
4. It would’ve made sense to generally optimize more for lightness. The wall now weighs about 100 kg, so we needed five people to lift it and put it in its shoes.

You’ll see more of it on my Instagram. At least once I come up with a problem I can solve.

Enhancements

1. Since the first setup, I’ve moved the wall by 66 cm toward the window to have more space underneath. That way I can swing out when I lose feet without hitting the wall (or without hitting it hard). The move also allows me to climb up a bit farther because I get get head up higher, and it allows me to start lower, because I can climb the first horizontal meter or so over the floor rather than the bed. That makes the area accessible that was previously blocked by the 25 cm high bed.
2. One of the bed slats broke, and I turned it into eight nice crimps and a hangboard. Very recommeded!