Please Help: Looking for a Composite Calculator.......

[S8AINTS]

I truly need your help. Just started a new position in which I need to calculate the amount of material (composite rolls) to purchase. My problem is that I really dont know / understand all the calculations and formulas to estimate this.

Is there a easy calculator out there where I can simply plug in items such as:

EXAMPLE:
Material: LTM12
Roll Width: 38"

Area of coverage: 10,000 sq inches
Thickness of Part: 3/8"
Isotropic ply layout

Im looking for a calculator that I can enter the basic information above and it will tell me information such as how many rolls I need to order.
If there's not such a calculator out there, and could point me to a VERY SIMPLE / BASIC walk thru on how to figure estimating for this type; I would highly appreciate it....


Thank you for your input / suggestions.

 

[berkshire]

If you find one, it will most likely be somebodies excell program.
You need to know the type of material , dry or prepreg.
The width, the number of yards on the roll, and the thickness of the compacted finished ply.
You can then use that information to determine the number of layers of that material to get the finished thickness you are looking for.
A number like you gave of the number of square inches, like 10,000 square inches means nothing without other sizes.
You could have a strip one inch wide by the length of the roll, if your roll is that long, or a 22foot long piece by 38 inches wide, or if your layer is 0.01" thick, 37 or 38 layers by 22 feet of whatever your material is.
This is basic math and basic estimating.
B.E.

 

[RPstress]

http://www.vircon-composites.com/4_2.asp

has a few tips on basics.

You'll need a few specifics like the amount of material typically wasted on your site (usually a percentage). It's often quite high even for competent manufacturers. 10% waste is rather low and 50% is a bit high. Also small numbers like how much is used in overlaps and joints for woven material can add up. A lot depends on how areas are cut out of cloth for different ply angles (nesting), much liked for optimisation by material cutting systems suppliers.

Be aware that often, if an areal weight is quoted by someone, it's of the fibre alone, rather than the total weight of fibre and resin.

Quite a bit of the basics for cloth go back to woven materials through history (areal (lb/square yard, grams/square metre) and linear (e.g. denier) densities), both for clothing and sailcloth.

As berkshire mentions usually this sort of thing is put in a spreadsheet. Your company's estimators should have a load of basic data they use all the time. Also suppliers are often ready and willing to help out.