glass quality?

[silvercleave]

Help!! Can anyone help?, Does anybody know a simple way of telling the quality of 2mm glass.

Have been offered 3 different qualities, the only difference I can see is the price, I suppose there is a way of seeing through this.

Perhaps a glass supplier may see this and help

Confused

[wessexpictures]

I know of two types of glass, Sheet & Float.

Sheet glass is the cheapest, BUT can have flaws in every sheet. Can be powdered or paper interleaved. Powdered can be difficult to clean.

Float Glass is more expensive, but is used by 90% of framers. This glass has very few flaws in, & is usually papered interleaved.

We only sell & use Float Glass!

If you need any more info, please send a email or give me a ring on 01590 681 681.

Regards,

Philip

[Not your average framer]

Hi Silvercleave,

From a framer's point of view the quality of glass is self evident.

1. Any surface contamination or surface markings which are not easily removable with a professional quality glass cleaner, would be considered by most framers as a quality issue.

2. Likewise any visible, or otherwise discernable defects in the glass, would also be considered by most framers as a quality issue.

I have no intention of naming names, so don't ask me, but I have used a number of suppliers over the five and a half years during which I have been trading and have experienced suppliers changing their source of supply and not telling me, when I re-order and expect to receive exactly the same quality as previously supplied.

The problem has always been the same issues, difficulty in cleaning glass, visually discernable blemishes in the glass and poor cutting properties. Every time this has happened and I discuss it with my supplier, they tell me that the have changed supplier and that I have been supplied with Chinese glass.

In my opinion cheap glass if it comes from China is not cheap at all. It often takes several attempt to remove the crud from the surface of the glass and too often you then find defects in the glass. Paying money for something which you end up throwing away, is money down the drain.

Good glass usually only needs just ONE very quick clean only to remove any dust and finger marks. We used to get some very good quality glass from Hungary, but alas no more.

Some suppliers are supplying glass from Egypt or the Philipeans, I have used both with absolute satisfaction. As always, "You get want you pay for", still applies!

Talk to you suppliers and ask them what the differences are between the types of glass which they are able to offer. If more framers refused to buy the rubbish, then perhaps the suppliers would stop offering the cheap crud at all.

[Nigel Nobody]

Have been offered 3 different qualities, the only difference I can see is the price, I suppose there is a way of seeing through this.

I guess I would ask the suppliers of the glass what features make the most expensive glass the best quality. Check it yourself, by cutting and cleaning it.

If it is indeed better than the others, your choice is simple. IMHO you should always buy the best quality glass you can find! It will be the cheapest in the long term!

[the glassman]

Hi to all the framers confused by the subject of this thread.

As regards 2mm clear glass (and as indicated by wessexpictures too), there's sheet (spelt with 2 'e's, pronounced with a 'i') or float glass - period.
The 'structured' pricing - if it relates to 2mm clear FLOAT, can only reflect (sorry! about that!) a cost differential to the importer. Only one of the three float manufacturers (Pilkington, Guardian and St Gobain) in the UK make 2mm (Pilks - and it is actually 2.3mm): they aren't keen on doing so, will not wash or paper-interleave it and won't sell in the preferred packing or sizes.
The main reason for this is - as the saying goes... 'size matters'. The average modern float-line will produce 600-1000 tonnes per day and if they're anywhere in the upper range of that, 2mm is pretty-well impossible as it comes off the line too fast to handle. At a 900 tonnes/day production rate, 2mm will leave the end of the float chamber in a continuous ribbon 3200mm (appr 10 feet) wide - at over 30 feet per minute!
So... forget UK 2mm float (sadly). A handful of smaller (400-550 tonnes/day) plants in Europe offer 2mm float and will wash/paper/package as we like it. This glass also tends to be of very high quality too, because most of it destined for markets much more critical than the Framing one (yes, as a Supplier, I'm amazed that they exist too!!). Main use will be automotive windshields (2x 2mm float, laminated together to give 4.4mm), electronics, lighting etc. In consequence of this, 2mm float from Europe will be a) very good - but b) pretty costly. To make matters (much) worse, we have the £/Euro situation to add 15% or so to the cost (since end 2008) AND .. all European glass carries a fuel-related surcharge on top! This is currently levied @ £80/tonne (= £0.40p/sq metre for 2mm) on all invoices and varies monthly according to the oil price in the preceding month.
So... forget European float unless a significant premium can be charged. This currently runs at about £0.70-80p per sq metre).

Nowadays most 2mm float for our little market comes from various places a long way east of the Nile. In these countries float-lines have to be essentially 'all-rounders' - supplying their local areas with float from 2mm<12mm (and sometimes more). They tend to be smaller too, thus facilitating 2mm production. For reasons a bit too boring to detail, 2mm float commands a lot more £££ per tonne than, say 4mm. For example, 4mm float (100 sq metres per tonne) sells at about 50% over 2mm (200 sq metres per tonne). Thus if 4mm @£5/sqm will produces a sale for the plant of £500/tonne, 2mm will give about £650/tonne. Thus in a small, flexible plant, used to paper-interleaving and timber packing-cases 2mm can be a profitable line.

The good news is that good quality float is not so much a matter of geography as of good plant management. There are several float lines in the far-east producing very good 2mm float (There are also many more that don't!). These good plants are usually wholly or partly owned by one of the major glass manufacturers in Europe, USA or Japan. Glass from these plants is the mainstay of picture-framing glass in UK... it is of good quality,well packed and paper interleaved. It is traded mainly in US dollars and does not normally carry the European fuel surcharge.

So... putting aside the occasional low-quality/wet/stained/tin-spotted float that appears occasionally (usually after some misguided Importer thinks they've found a new, secret, bargain-basement producer somewhere!!), nearly all our basic 2mm float is from the east (China, Taiwan, Philippines, Thailand etc) and is as good a balance of value and quality as you'll find. Problems here are with shipping cost rises, delays in transit, and £/$ exchange variations. Whilst the best European 2mm is certainly better quality, it is (sorry!) rather better than our market needs - and probably not worth the considerable premium involved unless you're very, very fussy. It does however have a short lead-time - and is very reliable - whereas the eastern material is on 8-16 week lead-times from order and can then be further delayed due to shipping issues. Long delays with papered glass can give rise to the once familiar paper-staining but many Plants now use a high-grade acid-free paper interleave to minimize this risk.

Wake up at the back! And please carry on framing.
Cheers,
The Glassman.

[Jonny2morsos]

A very informative reply. Thank you.

I have to say I have never shopped around extensively for glass and would be wary of anything offered at a cut price. Standard glass is cheap enough not to worry about. There are better ways of reducing costs if necessary.

John.

[silvercleave]

Wow What an answer!!!

Many thanks to all, a very informative and concise reply thats tells me plus anyone else just about all there is to know on the subject.

Worth saving this subject for future reference