The Framers Forum

Possibly a dumb question, but is there a general rule of thumb regarding glass thickness versus the size of frame?

And while I'm asking dumb questions, I'm planning to make a dedicated glass cutting table to reduce the risk of splinters on the main laying-up table - what would be the best surface? Something solid or something with a bit of grip like rubber matting? Interested to hear what other people use...

Thanks!

I use my judgement for your first question, depends on a few factors other than just size:

Thickness and or depth of moulding
Is the glass supported over most of its area, or does it have glass spacers
Is it long and thin

If the moulding is a chunky one, the piece has a good size mount, or no mount but not glass spacers then I'll use 2mm up to probably 4' x 3'

Above that I'll use 3mm up to around 5' x 4'

Above that I'd use acrylic

For a glass bench I'd use carpet for covering, but I use a wall mounted cutter so the need does not arise

Thanks for the reply Abacus, that's very helpful. On that basis, I probably don't need to keep a stock of 3mm until I specifically need it.

I've seen carpet used on cutting tables but wasn't sure if it would present problems with glass cracking during scoring. I'll have a look and see if I can find something with a very short, fine pile...

2mm glass is fine for most jobs IMHO. Over 4x3' you might want to think about acrylic, but more for the weight considerations than safety.

The thing is, a big sheet of glass is no more dangerous than a small bit. A no more likely to break. As long as it's set in the frame properly that is. If there are lumps under the frame rebate or the glass has a chip on the edge. Glass is actually quite difficult to break.

Obviously, the bigger the sheet the more meaty the frame has to be. Thicker glass will add a lot to the weight so you need an even stronger frame which also adds to the weight. Then you need bigger wall attachments. When push comes to shove, extreme damage will break a thick bit just as easily as a thinner bit. And the broken pieces are no less lethal.

..... As for cutting surfaces, I like short pile 'kitchen' carpet. As long as you give it a good hoovering now and then. If you do get an odd splinter on the surface it is less likely to scratch as it will get pushed into the pile, unlike a rigid surface. And if the table beneath is not perfectly flat (few are), then the carpet will tend to even out the hills and hollows and give better support.

That's my fourpenn'th anyway.

you don't want the glass to move on a cutting table so carpet is fairly useless as a covering - great for the main assembly table. The ribbed rubber sheeting that Lion sell makes an excellent covering - keeps the glass in place and allows small glass splinters to drop into the grooves thereby reducing scratch potential. As the rubber grip the glass firmly this surface is also very good for glass cleaning.

I did wonder about slipping on a carpet surface... I plan to build the table at an angle and I was thinking of having a lower lip to stop glass slipping and an upper lip for the T-Square.
I suppose I could experiment with surfaces once it's built but any further input would be great - pros and cons to both...

Thanks again

if you want cheap and cheerfull, go grab some of the plastic drawer liner ikea sell on a roll its a rubbery sheet with nobbles on it, grips glass hard, i have it on my assemble table

Glimpse wrote
"I did wonder about slipping on a carpet surface... I plan to build the table at an angle and I was thinking of having a lower lip to stop glass slipping and an upper lip for the T-Square."

My T-Square has to be against the edge of the glass nearest to you (in your case the bottom) the cutter is run down the length of the square and off the glass edge of the glass, so I don't see how you are going to cut yours.

Before I had a vertical board/glass cutter I used cushion flooring (posh lino) because the glass had to be slid and turned and it's not so easy to do that on a grippy surface, plus it's easier to wipe/brush something than it is to vacuum.

The short pile kitchen carpet yore thinking of is Flotex. Don't use it as it holds a static charge and fills your glass with charged particles that are a pain in the arris to get off... I'm a floor layer by trade and have used this at my cost. Grrrrrr.

Been cleaning glass on carpet for years and never had problems with static.