Shipping types

Just curious how people handle tshipping, do you charge by weight or have a flat fee?

I've been calculating shipping costs based on weight, which is fine for most of our products as they aren't that heavy. We have a few heavy products though and people are being put off by the high shipping cost, especially when shipped internationally. If we start charging a flat fee of say £3.95, are people going to be put off if the shipping costs as much or even more than our small items?

We also sell a range of items. So I now have a cart to add a handling charge and a sliding scale. So if they buy one CD its 1.95 but if they buy two its 2.49. If they buy a heavy item it costs what it costs us plus the small handling charge.

Im able to say 1 - 2 lbs 3.95/lb 2-4 lbs 3.25/lb 5-10 lbs 1.99/lb etc

I've found this to be accurate no matter what they order.

(The amounts are made up since their are so many currencies represented here anyway)

Cheers,
Jason