[jwi]

Vaguely related to thread.

I am planning to build a board in a room in our apartment and would like to make a custom pad so that the room look a little nicer than if having an assortment of random pads. I'm planning to get some form of filling, preferably made to measure in a single piece, and clad this in some form of nice looking, easy to clean felt. What kind of hardness should I look at? If I made the stuffing from polyurethane for instance, what kind of density should I look at? Is 40kg/m2 enough or way too little? 

[thunderbeest]

Hmm i see that the guys who did the matting in my gym used the following products: MA2538 15cm at the walls that are 3m tall + 5cm rebound foam RG80

I don't immediately find the density og them  but maybe you find it somewhere on the webs.
Also they just use standard 2000x1500mm

[JJP]

I've had this problem on my board with everything from the screw in t-nuts, pinning screws and screw-ons (which use Core's recommended size; M5 50mm from memory?). I put it down to the plywood compressing and the changing conditions (moisture?) from Summer to Winter affecting the wood. These were all smashed in without adequate care using an 18v impact driver.

Cheers, ye I had wondered if it might have been changes in temperature or humidity causing the loosening.  Think will just aim to re-tighten on a regular basis. 

If you really don't want them to move then get some gorilla glue on them. You won't get them back of again though in one piece though I don't think.

Had thought of doing that but tend to move my holds about fairly regularly!

 

[SA Chris]

I've just got a set of really crap screw-ons spaced regularly in the gaps between the holds that never get moved even if everything else on the board does.

[User deactivated.]

I have quite a few holds drilled for M10 bolts, but not so many that I want a grid of T-nuts on my board.

I intend to set my next board slowly over the space of a month or so, and i'd like to be able to place screw on holds and T-nut holds wherever I want, but I won't have access to the back of the board. Is there a good solution that doesn't involve removing the plywood and installing a T-nut from the back every time I want to add a new M10 hold (I won't be doing this)?

[M1V0]

Lonestar? It's a bolt-to-screw converter: https://www.climbingwallservices.com/collections/climbing-wall-equipment/products/the-lonestar-screw-washer-m5

[User deactivated.]

Interesting, although most holds will need more than 1 screw, so it would need to be supplemented with drilling additional holes in the hold. On plastic holds this might be a bit of a bodge.

[remus]

Interesting, although most holds will need more than 1 screw, so it would need to be supplemented with drilling additional holes in the hold. On plastic holds this might be a bit of a bodge.

If you want a more ghetto version of the lonestar you can just use a washer, I've got a few of the right size in the garage so will measure them up if you're interested. Combined with a chunky screw (6mm diam) these can work well. Helps to have an impact driver as they're pretty big screws.

If you haven't got too many holds, or you're adding them slowly, then adding extra holes for set screws is pretty non-faffy. I've done it with almost all the PE holds on my board as there are no t nuts. Just needs a 5mm drill bit and a countersink bit and you get a nice clean finish. Obviously you need to think a bit about where the holes are going but it's never been an issue on the holds I've put up (admittedly mostly larger stuff).

I haven't tried it on PU as all the PU holds I have came with screw on options molded in.

If you're feeling lazy then ramming a couple of 5mm screws down the bolt hole also works for most small to medium holds. Adding a pin screw helps stop any spinning. Not recommended for larger holds though, especially jugs. The extra leverage means you can rip holds off the board pretty easily. Recommended even less if you're also using cheap ply.

[Paul B]

You can buy the cupped washers pretty readily if you want something between remus' solution and the Lonestar.

[SA Chris]

If you're feeling lazy then ramming a couple of 5mm screws down the bolt hole also works for most small to medium holds. Adding a pin screw helps stop any spinning. Not recommended for larger holds though, especially jugs. The extra leverage means you can rip holds off the board pretty easily.

Didn't someone call this dirty euro somewhere?

[User deactivated.]

Since the lonestar thing is sold out, cupped washers with an extra pin screw doesn't actually seem like too much of a bodge based on your description. I'll be using 18mm ply and won't have any jugs, so it should be reasonably sturdy. Remus, if you could measure your washers that would be great.

[Paul B]

 I asked a route setter about this a few years back and have a photo of a bag of these:
https://www.orbitalfasteners.co.uk/products/no12-solid-brass-turned-knurled-surface-screw-cup

(the part numbers match).

[remus]

...and won't have any jugs...

Proper boulderer!

The ones I've used have a 15mm OD and 5.5mm ID. These look very similar https://www.screwfix.com/p/easyfix-steel-large-flat-washers-m5-x-1-2mm-100-pack/871ft

Pretty tight on a 6mm screw. 5mm + a set screw would be fine for non-jugs imo.

This is how they sit in use https://photos.app.goo.gl/2twsJVy7t367RF9B6

[User deactivated.]

Thanks all, I'll be giving this a try in the next couple of weeks.

[Bradders]

Yep as others have said I have loads of resin holds with M10 bolt holes and have always just used a larger (6mm max) diameter screw with a washer, or ideally some washer head Spax screws so no washer required!

[cofe]

I T-nutted mine but might use this approach to move a few of the awkwardly placed bolt-ons. Nice one. And my board does have jugs!

[tk421a]

https://www.accu.co.uk/solid-countersunk-washers/611609-HKW-M6-A1

Commonly used at commercial walls.

[User deactivated.]

Any thoughts on stud size and at what centers?

The Metolius guide states that steep walls greater than 9 feet in height should use 2x8's or even 2x10's at 16 inch centers. I don't mind a bit of over-engineering to be on the safe side, but this seems more appropriate for building a nuclear bunker?

For reference, i'll be going with a 2.7m tall 50 board (4.2m climbing length) supported by the existing structure (brick garage with a timber-frame floor above).

[jeh]

I used 50x125mm (2x5) rafters at 500mm centres for my moonboard and its solid as houses. However the rafters are fixed to a beam at the top and at half height so the span is smaller. If I only fixed at the top of the rafters I would probably go for a larger section size such as a 2x8. Its also worth bearing in mind the thickness of ply for deflection between rafters. I used 21mm and that is fine with my spacing, but if I were to use 18mm it may be worth reducing the spacing.  Bear in mind that this is for a super solid board and you could likely get away with far less.

[Paul B]

Sorry if I'm telling you something you already know but it's a combination thing; the ply is spanning between your timbers so closer c/c is asking the ply to do less work. In reality what this will change is how much it deflects. Thicker ply will deflect less in the same way a thicker joist (or higher grade joist) will deflect less for the same load.

I used 225 x 50 C24 joists (I think at around 600mm c/c - I can go and measure later on) with 18mm thk. ply and it doesn't deflect at all. I don't think it's over-designed but it IS more than most people would install (and I actually wanted slightly smaller timbers but didn't have the option 'cos pandemic etc.).

EDIT: What jeh said!

[User deactivated.]

Thanks both. It seems that 2x8's at 16 inch centers isn't a million miles out then, so i'll just go with something like that. I'll be using decent 18mm plywood too (which is extortionate these days!).

[Probes]

You wanna one of these...

https://www.timberbeamcalculator.co.uk/en-gb/span-table/rafters?load=0.75&class=C24&slope=30

2x6s should be fine, span tables saying at 45deg 2x6s will do 4m @ 400 centres. So 50 at 16 inch not a greate deal difference. And, these are span tables to hold up a roof!

I have a 50 board, which are 2x6 at 300 centres over 3.9m, which is also the roof (slate roof) and occasionally my misses. Doesn't budge a mm. 

[Moo]

Has anyone tried using concrete form plywood for a board ? it's not crazy expensive, hardwood and it has a hard wearing coating that'd provide a durable surface so on paper it'd be decent.

https://www.howarth-timber.co.uk/plywood-prc-120gm-film-faced-hardwood-core-18-x-1220-x-2440mm/?gclid=Cj0KCQjwyLGjBhDKARIsAFRNgW_1s5-LiBlAD3pu3iAwcXbO-rmYH9D_-F1JH01uTP8pa10Tv10XIbQaAs1AEALw_wcB

[thunderbeest]

It's always good if you can have a look at the plywood before hand. See how good the gluing is and how straight the layers are. If you can get your hands on a good 21mm birch without having to mortgage your house I'd go for that and even dare to go cc 120 for the rafters.
As the birch tends to come from Russia it hasn't been easy to get hold of.

[jwi]

As the birch tends to come from Russia it hasn't been easy to get hold of.

A friend started to import birch ply from Lithuania. Cheap if you buy in bulk.