Strong? wall cabinets

[JohnD]

I made some of these for the kitchen and utility. I am not much good at woodwork, they are 900x600x300 in 16mm MFC.

I used glued dowels to hold the top and bottom, and the middle shelf and the top and bottom partial back stiffeners, to the sides.

The small shelves are loose-fitted onto plastic block-brackets in 6mm or so holes bored into the sides.

The sides are hung on adjustable wall brackets.

the wall bracket steel plates are fixed with 4no 35mm screws about size 6 into a wall of dense concrete tri-wall bocks.

The thing is, I want to put stacks of china plates into them, which are very heavy. I don't suppose my cabs are any worse than you buy in the sheds, but what sort of strength should they have? I don't want them crashing to the floor and smashing the china.

Would it be an advantage to screw a batten to the wall underneath, for them to sit on, as well as the adjustabe brackets?

 

[Thermo]

cant do any harm

 

[pjholybloke]

IMHO I would say that your woodwork is ok, but your adjustable claw hangers/brackets are too far down the sides, would relocate to top corners personally, and 35mm screws?

Although putting a batten up won't hurt, it won't be as effective as a longer screw.

You're build quality is not in question, but the 10mm of screw in the blockwork (assuming its a dabbed board on surface) is very likely to part company in the face of the china.

70x5.0 if dabbed.

50x5.0 if brown & skim.

Brown plugs.

 

[JohnD]

Thanks!

Brown plugs, wall is sand and cement rendered internaly with thin hard plaster finish, I suppose 18mm total (it's a local method, I expect they would have used sand and lime once as we are a chalk, flint and sand area).

I put the hangers down there because I have a MFC stiffener below the top, as a a sort of partial back panel. Do you mean if it is at the top, it can take forces through the top panel as well as the screws into the side?

What sort of weight can a "shed" wall cab be expected to take?

I'll change the screws. i just happened to have a box of those others to use up

 

[pjholybloke]

It helps to spread the load between top and side but essentially the sides are the most important.

Unless you put heavy stuff on top of the cab, the stress on the top panel is really only an issue if the cab is out of level. If you have the brackets/adjusters at the top of the sides, and the sides are pretty much in contact with the wall top-to-bottom, it will reduce any leverage effect which is the major threat to wall cabs.

It's far more likely that a badly fitted wall cab will pull screws out of the wall through leverage as opposed to shearing them off through weight alone.

I'm not sure whether it's a British Standard (ES) requirement, but all weights I've seen regarding wall cabs refer to a 250kg breaking strain on the wall brackets - however, I certainly wouldn't try that at home! (mine or anyone elses)

If your cabs are level now, why not just drill through the stiffener and fix with a 70x5.0, will save the bother of taking them down.

 

[Jasonb]

As has been said putting the hangers at the top will help with their holding capacity which is actually 130kg for Blum hangers, this is based on 18mm carcases, as you have 15mm your screws will be a little shorter so allow 100kg max. And definatly longer fixing screws that go at least a plug depth into the structural wall not the plaster/render.

Coming back to the carcases "conti board" MFC is not as good quality as a decent MFC which usually comes 18mm and is a much denser board which means all your fixings and dowels will have less pull out strength.

Plastic shelf studs are also a weak point especially if the holes are not sized correctly "6mm or so" get some metal ones and use a lip & spur bit to get a clean edge.

Jason

 

[JohnD]

Thanks!

lots of things I didn't know...

I told you I wasn't much good at woodwork!