UKC

Struggling to get to the wall as often these days due to work and family so I'm thinking of building a small symmetry system board at home to supplement the fingerboard. I don't have a lot of space so the biggest it could be is around 1.2m wide and 2.1m tall - similar to this board at BlocFit in London (https://www.facebook.com/watch/?v=1175733879163159).

Plan is to be able to adjust the angle so that I can use it for training but also change it to a slab so my 1yo daughter can have a play if/when she wants to, and fold it up against the wall when not in use.

My current plan is pretty basic (see sketch here https://unsee.cc/563c0b4c/):

- buy a sheet of 18mm ply (https://www.wickes.co.uk/Wickes-Marine-Plywood---18mm-x-1220mm-x-2440mm/p/1...). It's pretty much already the right size luckily

- Put t-nuts in a 4"x 4" grid across the board

- put two anchor bolts in the wall behind the top corners of the board

- have chain or rope attached to the board which can be longer/shorter to adjust the angle

- at the bottom have the main board attached with some heavy duty hinges to another small board which rests on the floor (but not attached), maybe with rubber on the bottom to stop it slipping. This is so I can turn the board into a little slab for my daughter to play on. See drawing if this isn't clear.

I've had a look online but can't find many people who've built something this small so I have a few questions which I hope someone could help with:

- Do I need to build a frame behind the plywood or will the plywood have enough strength on its own given it's only one board and it will only be feet-on hand moves so relatively low stress?

- Is 4"x 4" a good grid size for the t-nuts?

- I guess the board will be ok at more overhung angles but I wonder if the board could bounce at less steep angles? Should I add something behind to fix it in place at different angles? Any suggestions how to do this?

- Any problems using old dynamic climbing rope to attach the board to the wall? It's going to stretch a bit but I guess that's ok?

Any thoughts or suggestions greatly appreciated!!

- Why marine grade ply specifically? Is this outside/not under cover?

- I would have the hinge not at the edge of the floor board, so that the load is spread more evenly to your floor.

- You would definitely want a light frame behind the ply to prevent excessive flex. I would go for 2x1 end on. Round the edge and 3-ish horizontals. All glued and screwed.

- It certainly could bounce if you plan to do remotely dynamic moves, if just moving gently around then you could probably get away with rope/chain.

- Dynamic climbing rope might give an interesting experience (could be the next big training breakthrough?). If you have plenty of spare rope then doubling up (or more) on each corner would increase stiffness.

Edit to add:

- If you are going steeper than the one shown in the video you would probably want another foot batten higher up. This could take the place of the lowest horizontal batten from your frame.

That looks pretty good. You'd want a frame on the back of the ply to stop it flexing as mentioned above.

I suspect it might bounce a bit if you're doing powerful/dynamic moves. You could add a few bits of 2x1 cut to form a |_| shaped cradle on the back of the board, and on your wall,  so that you can put a length of 2x1 (ie parallel to your rope in the diagram) to brace between the back of the board and the wall. The long bit of 2x1 can be easily slotted in and removed so you can fold the board up against the wall again. You'd have to get the measurements spot on and be able to set the chain/rope at the same length each time else there will be bounce until the board presses against the 2x1 struts behind. I hope that makes sense.

I spent ages T nutting my board (I think it's 4x4 inch and fine) but it's not really worth the effort, especially at this angle, as I think you'd be better off using screw in wooden crimps/pinches. Cut up bits of banister rail and different size dowels. Or use one of the many good companies making nice wooden holds who'd be able to supply you with exactly what you want.

Add a few additional footholds too rather than just rails, it will improve accuracy and core. The 'half wooden ball' footholds from craft shops on ebay would be great for this.

Thanks for the tips!

It doesn't need to go outdoors so I definitely don't need marine grade. Tbh I didn't think much about what sort of ply to get apart from not the 'non-structual' one. Would this one work - https://www.wickes.co.uk/Structural-Softwood-Plywood-CE2%2B---18mm-x-1220mm... ?

I think I'll just build it and see how the bounce/dynamic rope thing is. I have loads of old dynamic rope but can also buy some cheap static rope so no big deal either way.

Yeh, I need to think more about the holds/feet - I was thinking to buy a set from crusher holds and will definitely put on a variety of small feet and rails.

Thanks. I will try without T nuts for now and maybe get some screw on holds from crusher holds. I may need to put in some t nuts eventually to put in some jugs for my daughter to play on but I guess I can always add these later. Do you know which t-nuts you used? I have heard that the 3 prong ones can cause the nuts to spin but not sure whether to use 4 prong ones or the ones with tiny screws?

Good point on the feet - I was thinking to get some holds from crusher holds or hard wood holds. Maybe these feet; https://www.hardwoodholds.co.uk/store/c7/Footholds.html

If I get time then I might have a go at putting the frame together on Sunday - will let you guys know how I get on.

I used a the screw in T nuts. It didn't seem like much extra faff and they seat much nicer.You can get similar footholds a bit cheaper from craft shops on a well known auction site (bots won't allow me to post a link) if you don't mind drilling and countersinking yourself.

I built something quite similar to what you have in mind. 

  youtube.com/watch?v=t2gSQCVxnho&

I put some details in this post, if it's any help

https://www.ukclimbing.com/forums/walls+training/home_wall_-_what_to_go_for... 

Might be worth adding a failsafe if it's hinged, especially if you have a little one.

For example, a chain permanently fixed at just beyond the lowest angle you're ever likely to use, just for peace of mind. 

I've  built a much bigger and heavier hinged wall and have 5 independent fail safe points