Plywood shelving - thickness for supporting hi-fi

[David]

For the Hi-Fi rack in the fireplace I need some shelving.

I could go for 4mm glass cut to size at around £25 a shelf (online price from one site).

However that is £100 for 4 shelves. Plus I will need fixings, but they shouldn't be too expensive.

Alternatively I could use a sheet wood material.

I think veneered chipboard may be too thick at 18mm.

So I'm wondering if ply would be an option. One sheet is probably £30-£40 and there will be plenty of spare - in fact half a sheet should provide eight shelves with luck. The ply can also be shaped for cable runs etc. and even ventilated for better air circulation.

So the big question is how thick the ply should be. Shelf size roughly 500mm wide and 400mm deep. They will be floating shelves on pegs to allow moving up and down by small amounts.

seems to think that 10mm is adequate but that is for "Plywood, fir" and a US site.

So I don't know if I can rely on this.

Does anyone have a view on this?

Cheers

Dave R

[fred]

The important thing is how these shelves are going to be fixed. If they wi ll be fixed at each corner then 10mm would be adequate. If they are going t o sit on shelf pins or pegs then you need to consider how the weight of the equipment is going to be spread, If it sites on 4 feet and these feet woul d come close to the corners of the shelf than again I think you would be ok . If the weight was in the centre of the shelves I would be a bit more care ful. Perhaps 12mm.

If the shelves are going to be supported from underneath by brackets than y ou would be fine as long as you allowed adequate overhang at each side.

Get good quality ply. Marine ply if possible but not necessarily the LLoyds approved type which would make you nose bleed.

This site might assist you

Compare to mdf or chipboard ply is much stronger.

[Martin Bonner]

Adding a (say) 25mm strip of lipping at front, and 50mm at the rear would increase the stiffness dramatically

[David]

Thanks - noted.

[GB]

Would it not also look better? I guess that's a matter of taste, though.

[spuorgelgoog]

A false back underneath the shelf would also help hide the cable clutter.

Owain

[Nick Odell]

There's a huge cosmetic difference between 18mm ply and veneered chipboard so what effect are you trying to achieve? How much loading will each shelf have to bear - ie: is this a valve hi-fi with massive transformers?

Consider blockboard (lighter than ply) or even making up a hollow shelf in the style of a modern flush door with hardboard or thin ply either side of a border (and a couple of interior spacers) of thin softwood. The box section makes it incredibly strong for its weight.

Nick

[John Rumm]

It would...

Especially if you lip the cut end in real wood.

Even at wicks prices that sounds a bit steep for 1/2" ply...

Given the shelves are quite deep, and hifi kit will tend to have feet toward the edges, 12mm / 1/2" ought to be more than adequate.

I have never been that convinced by that calculator for larger timbers, but its probably fair for shelves.

You can get softwood ply (wicks again) which is a little lighter and still pretty strong.

I built this last year:

All the shelves are 3/4" ply with a wood lipping (same thickness as the shelf) and they are simply resting on shelf support tabs at the sides. Even the shelves loaded with a full row of large heavy hard backed books show no sag at all. Given your shelves would have a much kinder load, and also be twice as deep, I doubt you would have any difficulty reducing the thickness to half inch.

(also note that even if you went for 3/4" ply with a wood lipping, the shelves do not loop particularly "heavy" - especially if you roundover the wood edge)

[meow2222]

half inch chip would do for that, as long as it doesnt include an ill-sprun g record deck. 12mm ply is stiffer. OSB is cheaper.

NT

[harryagain]

Plywood is good.. What you need s some timber stiffeners glued on underneath out of sight. That way the ply is just for appearance, the stiffeners take the load. You could even put a stiffener across the front if you covered it with ply. This avoids showing the cut edge of the ply. You only need thin ply or even veneer/other finishing material.

Or just have a timber rail across the front and rear with some sort of sheet material (ply, chipboard etc.) set into it.

Very thin fronts of shelves look shit IMO.

[David]

I'm trying to achieve a shelf significantly thinner than 18mm to get more space for kit and also make the shelves a little less of a feature.

4mm glass achieves both of these but is relatively expensive compared to wood, and inflexible with regard to shaping during/after installation to modify cable runs and improve ventilation.

The plan is to have a hi-fi style enclosure with pegs up both sides to allow the shelves to be moved up and down as kit changes.

Internal height is roughly 830mm and I'm hoping to fit in four units, using 3 shelves and the base. However I would like the flexibility to put more units in if needs be.

8mm per shelf isn't a massive saving.

Using glass and saving 14mm per shelf looks attractive, but as I said it is far less flexible.

Cheers

Dave R

[Dave Liquorice]

They way things are going you might regret not having a fireplace. B-)

But they'd be quite heavy.

SWMBO'd office has shelves made from 12 mm ply supported on brackets at about 500 mm. Front edge has a 12 x 25 batten attached underneath and the exposed face covered by a strip of flattened "D" profile beading. No sag loaded with books (books is heavy).

Depending a bit on the HiFi, (1 kW AV amp with big lump of iron or solid state boxes of air) 12 mm might be OK on it's own but the batten doesn't have to be along the front it could down the middle or back.

You could make a feature of the ply by sanding back to expose the layers and reduce the apparent shelf thickness:

il-2000B.jpg

arthbowl.jpg

sculpture.jpg

[John Rumm]

Oops that was supposed to be "look" heavy not loop!

Indeed...

It can even be part of the support at the back if fixed to the wall.