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Glass shelf thickness
02GF74 - 10/10/17 at 07:25 PM

I've got a hifi rack with 400x465mm toughened glass shelves. They are supported at the corners by resting on small triangular fillets welded to the frame.

I'm trying to find out what thickness of glass I need to support 50kg (actually 42kg with a bit of safety margin)

I'm not finding any data and manufacturers I've contacted are not committing. All I have so far is 4mm is good for 20kg so I extrapolate I need 10mm.

And supplementary question is how can I tell if the corner tabs are strong enough.?

[Edited on 10/10/17 by 02GF74]


tegwin - 10/10/17 at 08:11 PM

In its simplest form this is just a bending beam question but with glass instead of steel or wood..

This is for laminated glass so not exactly what you want but might help you out. Sure another 5 mins of googling would find a calculator thats right.
http://www2.dupont.com/SafetyGlass/ja_JP/tech_info/beamCalculator.html


SteveWalker - 10/10/17 at 10:29 PM

quote:
Originally posted by 02GF74
I've got a hifi rack with 400x465mm toughened glass shelves. They are supported at the corners by resting on small triangular fillets welded to the frame.

I'm trying to find out what thickness of glass I need to support 50kg (actually 42kg with a bit of safety margin)
[Edited on 10/10/17 by 02GF74]


Jesus. I thought my 23.5kg valve amp was heavy enough, what on earth are you putting on it?


02GF74 - 11/10/17 at 05:51 PM

quote:
Originally posted by SteveWalker

Jesus. I thought my 23.5kg valve amp was heavy enough, what on earth are you putting on it?


Krell ksa 150


loggyboy - 11/10/17 at 08:27 PM

Most glass bathroom scales only use thin ish glass. And they take a good 100kg.


gremlin1234 - 11/10/17 at 09:08 PM

quote:
Originally posted by loggyboy
Most glass bathroom scales only use thin ish glass. And they take a good 100kg.
though they are held up on pillars about 250mm apart, would need thicker glass when its a bigger span


trextr7monkey - 11/10/17 at 11:02 PM

Hi
We buy odd pieces of toughened glass for jobs kids make - usulaay coffee table tops and dressing tables etc
Some jobs have used drilled tempered glass as structural members
Small pieces are usually 4 mm and bigger spans 6

We have never had to use 20 mm yet! Sounds like over engineering l
I'm certain your local glass place will have someone who can advise
We usually send a template unless it is a regular shape
Hth
Mike


Bluemoon - 12/10/17 at 06:07 AM

That's a proper class-A amp

You will not need any heating in that room..

[Edited on 12/10/17 by Bluemoon]


Mr Whippy - 12/10/17 at 11:36 AM

quote:
Originally posted by Bluemoon
That's a proper class-A amp

You will not need any heating in that room..

[Edited on 12/10/17 by Bluemoon]


will need hearing aid in the future though


Bluemoon - 12/10/17 at 01:08 PM

Maybe, class A amps have a low output, as most goes as heat....


HowardB - 12/10/17 at 01:20 PM

I agree, I have a pair of 100w amps that keep the cellar nice and warm - they play silence beautifully


02GF74 - 12/10/17 at 03:37 PM

quote:
Originally posted by Mr Whippy

will need hearing aid in the future though


Quite possibly as age is not on my side.
Amp is rated at 150w into 8ohm and doubles as speaker impedance halves down to 2 or maybe 1 ohm!!!!

A tiny Walkman or phone listened to at high volume with headphones will damage hearing just as easily.

I don't turn up the volume too high as it brings on tinnitus.


nick205 - 13/10/17 at 08:47 AM

02GF74

Appreciate perhaps wanting to keep the look with a glass shelf, but a sheet of stainless could be a more cost effective answer.

Also, does the frame itself have a weight rating? You describe metal corner pieces supporting the shelf - be a shame to overload the frame and end up with the whole lot on the floor!


flak monkey - 19/10/17 at 05:12 PM

It does depend slightly on the size of the support pieces but off the top of my head 8mm toughened would be fine. The amp will have 4 feet close to it's corners so the load is quite uniform over the glass with little bending moment.

However if you drop the amp on it, it will break. 10mm laminate would be more robust. And I'd recommend a foam/rubber pad between the glass and the support tab


We've just done some rather cool glass design/install in one of the major airports using a mixture of 12mm and 20mm laminated and toughened glass

https://photos.app.goo.gl/5HJMXtCZKFjfvRHE3