measuring surface of a component

Can you be a little more specific? Area, roughness, UV reflection, ................ ?

its smooth surface...a plastic component having complex shapes, curved surfaces.as i got solution as breaking into simple geometric shapes..measuring and summing all...but want to know what type of measuring instruments are to be used?

Woof!!! That's a real toughie! No wonder you haven't seen much action.

Surface area is relatively easy to determine for simple geometric shapes, but if you're talking about something complex, like a spark plug or something like that, then I think you're looking at breaking the shape up into as many simple geometric shapes as possible, and then summing their collective surface areas. Also, I'm pretty sure you're looking at a calculus problem here.

Possibly coat the object with some sort of removable molding material, then remove it, lay it out flat, and measure the area of the "skin?"

Good luck! If you get a good answer please let us know.

good answer...but want to know what type of measuring instruments are to be used..other than vernier,micro meter...

The thing you're after is a CMM (co-ordinate measuring machine). Only problem is, they're expensive - don't suppose you'd even get a used one for less that $10k.

If you only want to do a few parts, you could go to a specialist inspection company, or find a CNC company with one, willing to do the measurements for you.

If you have money and it is not an one off job, you have quite a few laser intruments available.

These instruments can not onlu check the surfaec but can make a 3 D plot of the surface based on scatter points - used for reverse engineering

Also used for part inspection, as you feed the 3D CAd model, it can highlight the areas out of tolerance. We had a demonstration of these equipments a couple of years back for our blades check.

We didn't go for it due to economics but the equipment was impressive and expensive (near to $2,00,000).

The problem was the versatility (the otherway round) - it can be used for small to very large surfaces - upto tesns of sq meter - compromising a bit on accuracy.

The company was Geo something you can google (provided your economy allows)