UKC

I do some setting at a local scout climbing wall and I've ran into a bit of a nightmare situation. The problem is when they built the wall they didn't consider access to the back of it or the security of the t-nut placements. This has led to t-nuts being pushed out the back of the boards leaving a useless hole.

There is no way for us to replace them aside from taking down the roughly 2m by 1m boards. This is only a valid solution at the lower levels and is still a horribly time consuming and ineffective solution. We're eventually going to run out of places to attach holds and we have no way of adding new ones.

So does anyone have an idea? Maybe some way of securing holds from only one side?

Build a low profile volume with t-nuts in it and attach that? Hardly ideal though.

In reply to lewis.m:

You can get screw in inserts if you have more than 20mm or so thickness on your boards, some on ebay and elsewhere if you have a google

In reply to Murd:

They look great. Do you have experience with them? Thanks

In reply to lewis.m:

Buy screw on holds. A lot of companies produce them including www.stonesmithholds.com

In reply to lewis.m:

Afraid I don't, my local wall were going to try them on a wall they couldn't get to the back of....if they did I'll re post here though I don't think they have yet.

In reply to lewis.m:

You can use metal cavity fixings (plasterboard umbrella fixings) in the the same hole. These will allow you to bolt on smaller holds like screw ons using M6 countersunk bolts. Not ideal, but the best cheap thing I can think of.

Lindapter do a range called Hollo-bolts that allow you to install from one side. They are expensive and single use. You may also need the swap to M10 bolt for csk before you install them.

You could also try an M10 rivnut but I'm not sure they are available large enough to suit 18mm ply.

Steve

In reply to lewis.m:

Or these :

http://www.jpldirect.co.uk/catalog/Rawl_Nuts_K30200.html

Steve

In reply to lewis.m:

Depending on the gap behind the wall you could use a hole saw to cut out a big (~100mm diameter) hole that you can put your arm through to reach behind and replace the T nuts. You could then just plug the hole back up with the offcut from the hole saw - having put a couple of brackets in behind to stop it falling through too. This only works as a long term solution if you lay out a grid of holes that give you access to the whole wall, and then cut them as you need them, which may turn out to weaken the wall a bit...

Alternatively, if you can get over the top of the wall, then you could drop a small plumb line down behind and use something similar to an abalakov threader to hook it through the hole. Then attach a T-nut to the end of the string and reel it in until the t nut is trying to come through the wall. Never had to put them in myself, but tugging on the string might get it in, if not, you could fashion a tool that goes in straight and then bends 90 degrees that you could give a good yank on to seat the t nut. This would be a bit of a faff, but it shouldn't be too hard to train the scouts to do it themselves.

In reply to lewis.m:

Hang on, I can refine that idea..... http://i60.tinypic.com/1qmu6e.jpg

Should be the kind of thing you can set the Scouts as a puzzle to do.

In reply to sbc23:

Thanks for the reply. Going to look into a few of these. Do you know if the rawl nuts are reusable? What are the downsides of using the metal cavity fixings?

Thanks
Lewis

In reply to lewis.m:

Never used the rawl nuts so don't know.

The cavity fixings only come in M4-M6 as far as I can tell.

Steve

In reply to lewis.m:

The other way is to cut out a big hole and fix the t-nuts. Then fill the hole with an insert hold. EP Sell these they sit level with the edge of the wall and create good pockets.

The other way is to buy some ply wood cut out some shapes and t nut them,then screw this to the wall lining it up with the holes you dont have t-nuts in. You can build up features on the wall and make more positive holds. Try 3 sizes of circles or stars.

Failing this try screw on holds.

Hope this helps.

In reply to lewis.m:

before you lose any more buy a load of dome headed bolts(15-20mm long) to place in any un-used t-nut placements before they fall off also & make a point of doing this when you re-route & also if you find a way to replace those that are already missing

In reply to Oo:



T-nuts need hammering in to seat them well. otherwise they'll pop out as soon as you try to screw a bolt in

In reply to goose299:


If after seating it you gently hand fit a bolt & tighten it then it will be seated fine.

In reply to sbc23:




This looks the best answer.

Try a few M10 or M8 ones.

Alternatively try drilling some large holds so they can be screwed on with two or three no. 12 woodscrews. You might crack one or two but hey ho.

I would be surprised if T nuts were fitted at all when the wall was first built, maybe standard nuts on the back with no thought about hold resetting.

In reply to lewis.m:

Not sure I've read the comments thoroughly but I don't think anyone has suggested these:
http://www.castorsunlimited.co.uk/m10-x-25mm-threaded-wood-type-d-insert-nu...

Use large allen key to screw insert into the hole with missing t-nut. They work well