How to evaluate foam for furniture?

[baileyuph]

What method works for evaluating foam?

a.  price

b.  density

c.  (the factor that gives it the ability to return to original shape - IDF?) Elasticity

d.  There are other factors

How do you evaluate foam to be used?

There are several parameters, just a few have been listed here, can anyone list the formal parameters?

As a comment, the cost of the better stuff has risen over the last few years and new furniture foam has been observed to collapse in short time.  Understandable that cheaper would be used to restrain cost.

This is primarily a search for the evaluation parameters, there are a set that should be used?  Most refer to density while there are other proper parameters to consider.

Doyle

[kodydog]

We always order by the numbers as discussed on another thread but one other test to consider, the velvet hand. If it feels rough and like a board it is probably cheep. If it feels like velvet its probably higher quality.

[gene]

Density is the weight in lbs divided by the volume in cubic feet. I've got a note that says 18 lbs/cu ft minimum are needed for seat cushions. All I can do is trust that the supplier is telling me the truth.

IFD = Indentation force Deflection. This is a measure of firmness - how much weight is needed to compress the foam to 75" of it's thickness. I've thought of getting several weights and taking occasional measurement samples myself to compare different sheets and such, but I haven't done anything with it yet. I think if I got into buying major volumes of foam I would probably do this to help track what I was buying.

I like kodydogs' velvet hand test. I wonder if the velvet feeling is because of a greater density of foam? Less air and more polyurethane?

On pricing, I convert the price to $/sq. inch on my Excel spreadsheet so I can compare different sheet lengths, different sheet widths, and different thicknesses.

gene

gene

[Rich]

I work with dental chairs and I have yet to find a supplier that has foam in as good a quality as what has been (and still is) used by the manufacturers of the top name dental chairs. I have recovered many chairs that were made 30 years ago and not replaced any of the foam because it was still in very good shape.
I don't pursue finding out what it is or where to buy it because what I work with is costly enough as it is and I'm sure this stuff would unnecessarily add to my material costs.
Rich