[Paul B]

Cross piece A can be smaller cross section (3"x1" ish?) and lie flat to the floor?

SF used ply which seemed very sensible.

The bolted connections require a timber to deviate by the thickness (2") don't they? This isn't good for your coach bolt (will it fail? ...probably not).

You won't be able to easily fix your horizontal rails/noggins without offsetting them.

I think there's a typo in your post and you meant 2 x 6" for the struts?

I don't really understand why you'd have the outer timbers on the climbing surface as 2 x 6" and the others as 2 x 4" apart from the increased shear area for your bolted connection.

If you imagine the self-weight as uniform pressure (simplification), the 2 x 4 are taking the load from half the span to the left and half the span to the right (in terms of their bending) whereas your 2 x 6 only has half a span (i.e. either nothing to the left and half to the right, or half to the left and nothing to the right).

Not an engineer or even close, but why not have the supports (the non board side of your triangle) vertical or at least more vertical?

If you think of the climbing surface as a beam, supported at the ends (foot and head), the reaction at the head will have a horizontal and vertical component (normal to the surface). You want the majority of that to be applied axially through the strut. If you take a home ruler and stand it vertically in front of you applying load to the top and poke it from the side, you'll see it doesn't like it very much. The same applies here. It's obv. more complex than that as it depends on what the climber is doing.

[Will Hunt]

Paul will give you a proper answer, but this looks quite similar to my board though your design is a bit different. I don't have a bar at the bottom in the landing zone. I would have thought that putting in the 2x4 spacers on the back would have given you enough side sway support (definitely listen to whatever Paul tells you though - I can't even remember if I have spacers on mine.
What I do have is two 2x6 side stays joining the back to the front struts, creating an A frame. They gave me a lot of confidence (who knows whether it was well founded) that it wasn't going to come crashing down. And I think I had the wood left over from the big lengths of 2x6 that I bought.
I think the front legs of mine don't extend as far out as that. I don't know what's proper engineering, but I do know they shouldn't be vertical.

Worth bearing in mind that a garden board will probably merit more in the way of side sway support because it will have to cope with the wind. Having ply on it turns it into a sail. The 2x6 will be hefty and hopefully weigh it down, but maybe consider anchoring it to the ground in some way (especially if it ends up being top heavy for any reason).

[Yossarian]

Paul

Very helpful, thanks. So if the entire board side was 2x4, the 2x stays on the non-board side 2x6, all joints butted / ply sections overlapped and screwed through, section A is ply (screwed underneath so lying flat at the base), and the noggins tweaked, I’d be getting there...?

[chris j]

Ok, this is a bit of a crap and rushed diagram which will probably offend all the engineers...

I’d like to build a board at 35deg, with room for 4x 8x4 sheets up, but probably only 3x to start with.

My main questions are re the timber sections (2x4 for the 4x main vertical pieces, 2x4 for everything else), relative merits of overlapping and bolting through at B and C vs butting the timber up and screwing through a ply lapping section (ie the two diagrams at the bottom), and the cross piece A - I always remember landing on this in the past, though in this case it would be relatively further back if we’re not climbing to the top of the frame.

Any thoughts?

I have a broadly similar freestanding concept, just under 3m vertical height so rather smaller. I've found the wall solid enough if there is ever an eathquake i'll be hiding underneath it... I don't have cross-beam 'a'. I do have a direct cross-beam between the side triangles at the top. I also put in extra bracing on the sides so all the load doesn't go through the one joint at the top. Side wood is 2x6, wood behind the ply is 2x4. Joint at the top is butted, others are bolts...

The angle on the front stays is about 15 degrees off vertical. My main concern was to keep my bodyweight inside the triangle if i cut loose while minimising the footprint.

Footnote, i'm not an engineer...

Edit, found my post on here with some photos of the build if they are any help.

https://ukbouldering.com/board/index.php/topic,3260.msg458441.html#msg458441

[Nutty]

Worth bearing in mind that a garden board will probably merit more in the way of side sway support because it will have to cope with the wind. Having ply on it turns it into a sail. The 2x6 will be hefty and hopefully weigh it down, but maybe consider anchoring it to the ground in some way (especially if it ends up being top heavy for any reason).

My garden board is bolted to concreted in post brackets. Removes the need for the cross piece A and stops me worrying that its going to take off in a storm.

[Paul B]

Worth bearing in mind that a garden board will probably merit more in the way of side sway support because it will have to cope with the wind. Having ply on it turns it into a sail. The 2x6 will be hefty and hopefully weigh it down, but maybe consider anchoring it to the ground in some way (especially if it ends up being top heavy for any reason).

I'll give a rough internet opinion that should definitely be checked specifically for your case/location by a qualified competent person 

The wind is another good point. Working wind pressure is 0.2kPa. It's pretty easy to do an over-turning calc on a fag packed based on the sail area of the board acting half way up, compared to the CoG of the board (half way out from the foot of your climbing surface). Even for temporary stuff (~1yr) it's common to look at both working wind and peak (which is considerably higher [~x 3-4) and depends on things like where you live); You can also do with the same with sliding (sail area x surface area gives you a Hz force which is resisted by the self weight of the thing x friction factor). Both of these checks usually target a FoS. I'd consider whether you think it might blow into anything important and how long you're intending it to live for.

For anyone utterly bored this is useful for providing context.

[Paul B]

My garden board is bolted to concreted in post brackets. Removes the need for the cross piece A and stops me worrying that its going to take off in a storm.

Sense.

[mrjonathanr]

With more frequent board use I am really appreciating how superior wood holds are over resin. Much friendlier for tips.

[Fultonius]

In order to simplify build, I'd not bother with a kickboard. If you feel you need one later, it's an easy retrofit. My board is 26 deg and i don't miss one. Not sure the side board is worth the bother at all, and if you do put one in, for the complexity of putting a 10 deg board in, you might as well just go vertically, and not lose any room at the top of an already fairly narrow board. Don't bother with a vertical finish, additional construction faff. KISS.

I thought you know me better Chris - overcomplicating things is my MO!  The sideboard needs to clear the roller door, so the 10 degrees is more about maximising the width of the base. I could further complicate matters by kicking it back to vertical at the top on the side board 

[Lopez]

I've been using my exercise allowance these last few days to cycle around town searching skips and looking for any wood i could use to make holds but couldn't find anything suitable seeing as i don't have a belt sander. However last night i struck gold, so thought i'd share it so people in the same situation know what to look for.

A wooden handrail.

Ridiculously easy to make any sort of hold and fine tune them from pretty good to downright filthy all with just a jigsaw and some sandpaper. Pinches with small flatties on top, medium crimps, small and nasty crimps, etc all in like half an hour and the wood feels as solid as it gets 




Oh and also slopers/mini jugs

[tomtom]

PS. Big thanks to who suggested liquid chalk.. (can’t remember who - sorry) got some yesterday and it’s (a) weird and (b) much less messy to the room.

Suspect it’s also decent hand sanitiser too....

[Lopez]

Mmmhh...  Wood still not good enough for small footholds.

Any tips on what could be good for that? It seems anything under 15/20mm just snaps, and at that size all my footholds feel like ledges. Already had 3 footholds breaking and can't be taking uncontrolled falls as the risk of injury is pretty high...

[tomtom]

Mmmhh...  Wood still not good enough for small footholds.

Any tips on what could be good for that? It seems anything under 15/20mm just snaps, and at that size all my footholds feel like ledges. Already had 3 footholds breaking and can't be taking uncontrolled falls as the risk of injury is pretty high...

Hardwood Jenga blocks.

[chris j]

Mmmhh...  Wood still not good enough for small footholds.

Any tips on what could be good for that? It seems anything under 15/20mm just snaps, and at that size all my footholds feel like ledges. Already had 3 footholds breaking and can't be taking uncontrolled falls as the risk of injury is pretty high...

I do like these from Core:

https://coreclimbing.co.uk/buy-holds/climbing-holds/geo/geo-screw-on-feet-board

They have smaller ones also...

[Lopez]

Those core footholds are a pretty good price, thanks. Jenga blocks also sound good, i'll have a look on ebay see what they are going for as i can;t see any turning up in skips any time soon. Cheers

[Nutty]

Mmmhh...  Wood still not good enough for small footholds.

Any tips on what could be good for that? It seems anything under 15/20mm just snaps, and at that size all my footholds feel like ledges. Already had 3 footholds breaking and can't be taking uncontrolled falls as the risk of injury is pretty high...

I've got quite a few of the Crusher Dinks on my board that are oak and have been good http://crusherholds.co.uk/wooden-climbing-holds/crusher-wood-footholds and as tomtom suggests lots of people use jenga blocks so wood is fine for footholds as long as it's a suitable wood. I've quite a few wooden half-ball domes as well which are birch (these were off ebay). Hard Wood Holds make their wooden footholds from beech.

[Fultonius]

Can you make footholds out of plywood?

[SA Chris]

Don't think they'd hold up under use much. Hard wood, or even soft would be better.

[Adam Lincoln]

Just by these.... i know a few people using them. If they are too hard for you cut a nick out the top. Job done.

https://www.ebay.co.uk/itm/123869199661

[Lopez]

Plywood just splinters as soon as you touch it, so no good.

 Adam those look awesome. Estimated delivery between April 29 and June the 2nd though... Good lead anyway, Loads of different sizes and wood types when searching ebay for "Wooden Split Balls". Nice one, loads of options now 

[Lopez]

Just ordered a set of each of these

https://www.ebay.co.uk/itm/272714162159
https://www.ebay.co.uk/itm/272870005277

If they work ok at just over £5 for 16 footholds is a bargain 

[Schmiken]

Just ordered a set of each of these

https://www.ebay.co.uk/itm/272714162159
https://www.ebay.co.uk/itm/272870005277

If they work ok at just over £5 for 16 footholds is a bargain 

Thanks dude, just ordered the same!

[JJP]

Mmmhh...  Wood still not good enough for small footholds.

Any tips on what could be good for that? It seems anything under 15/20mm just snaps, and at that size all my footholds feel like ledges. Already had 3 footholds breaking and can't be taking uncontrolled falls as the risk of injury is pretty high...

I've got quite a few of the Crusher Dinks on my board that are oak and have been good http://crusherholds.co.uk/wooden-climbing-holds/crusher-wood-footholds and as tomtom suggests lots of people use jenga blocks so wood is fine for footholds as long as it's a suitable wood. I've quite a few wooden half-ball domes as well which are birch (these were off ebay). Hard Wood Holds make their wooden footholds from beech.

Ye I have a lot of the Crusher dinks as well - really like them and they seem solid.
 

[Lopez]

Crusher are out of stock of everything and not taking orders though

[Probes]

This is only temporary, until I've cleared the lock down back log. One product I do have is a box load of is the foot dinks, about the only thing.  If you want some, email me through the address on the website or pm and I'll be able to sort. Cheers.