Dave,
The issues with (that will always remain) are the way the paper calculations are done in the US and in the Metric System
US.
The US standard is the most confusing -
the same paper can give different values based on the “Basis Weight” applied while making the paper.
The “Basis Weight” is the weight of 500 sheets of paper in its basic unit uncut size - before being cut to size the paper is weighed to get the weight.
- But there are issues here as the basic uncut size differs depending on the type of paper! There are a number of paper types - Bond, Book, Index, Cover, Tag, Points, Offset.
- E.g. for "Bond" it is 17x22". For "Cover" 20x26" and so on....... This means that the Basis Weight differs between types!
- Additional factors also include (as well as the mass of the basis ream), the number of sheets in the ream, and the dimensions of a sheet in that ream.
- And the different paper mass also gives different weights.
Higher lb weights also don't equate necessarily to heavier or thicker paper - for example 80lb Cover paper is thicker than 100lb text!
- The weight remember that is given is the weight of 500 sheets of paper in its basic unit uncut size.
Metric (and UK).
Simple - grams per square meter (g/m2) - for all types of paper and paperboard.
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The above means attempts to use conversion charts between US and Metric paper are generally doomed, due to the resulting confusion!
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Dave - you are talking about Card Stock. I think this may be what is called "Cover Stock" in the industry as well, and if so this would equate to yes, 176 gsm/grms - in the UK 160 grm paper is common, but 180 grm should be available as well.
You also mention 110lb =199 gsm. Is this now "Index Stock" (not Card Stock)? 110 lb of Index = 203 gsm. In Card Stock 110 lbs = 300 gsm - which is really heavy and won't fit in most printers.
Assuming this is Index Stock, then in the UK your customer should ask for 200 grm (available as a standard size). If it really is 300gsm then I have no ideas!
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Buying in the UK - apart from 80 grm, mail order (as has been mentioned) is the best route for the other sizes. Same day/next day delivery. And use grm/gsm as the measurement term.
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And Dave, you said
"card measurement isn't really the factor."
I beg to differ - at the end of the day the client is trying to get the same thickness of paper/card you are using. So if you measure the paper, I can then do the same this end with Metric paper to check the above is correct.
Manufacturing tolerance on the paper thickness is 5-7%. So measure several sheets for an average.
And I'm not in the UK but the metric paper sizes are standard globally where they are used. And the end of the day we are talking here about a US to Metric conversion.
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