I think you're on track. And yes,I would concur that sample size would change things from here: http://www.pfa.org/jifsg/jifsgs4.html "It is also necessary to report the entire sample size. Sample size, in addition to thickness, can drastically influence IFD readings."
But you could just convert to PSI and have a uniform measure across the board, right? -Dave On Thu, Sep 2, 2010 at 12:37 PM, Kurt Nolte <[email protected]> wrote: > So... if I have a PSI (25%) deflection value of, say, 4... that would > be a minimum ILD of 96 (4 pounds/square inch * 24 square inch minimum > sample size), if I'm understanding correctly? > > The Foambymail quote seems to be saying they use a big foot (50 in^2) > on a possibly much smaller sample (24 in^2); it would seem that ILD > would thus depend on the sample size... > > -Kurt > > > On Thu, Sep 2, 2010 at 10:21 AM, David Cummings > <[email protected]> wrote: >> From the foambymail website: >> >> ILD: Indentation Load Deflection - A measure of the load-bearing >> capacity of foam. ILD is generally measured as the force (in pounds) >> required to compress a 50 square-inch circular indentor foot into a >> 4-inch thick foam sample no smaller than 24-inches square to a stated >> percentage of the foam's initial height. Common ILD values are >> generated at 75% of initial height. >> >> -Dave >> >> On Wed, Sep 1, 2010 at 11:06 PM, Kurt Nolte <[email protected]> wrote: >>> That's just it, man. I'm reading through McMaster's spec sheets for >>> their closed cell polyethylene foam. The densities seem to cap out at >>> 5 (with 2.3 and lower being more common) and a "PSI (% deflection)" >>> spec instead of an ILD. I get a tensile strength, and occasionally a >>> stretch limit range, but no compression modulus... I'm rather >>> disappointed, this time around. >>> >>> I've used McMaster numerous times before, usually I get a lot more of >>> the info I need than I am this time. >>> >>> -Kurt >>> >>> >>> >>> On Wed, Sep 1, 2010 at 10:45 PM, Allen Thomas <[email protected]> wrote: >>>> Mcmaster carr sells practically everythin including any foam you could >>>> want and the have spec charts to help you figure out what you want if >>>> you don't know. >>>> >>>> On 9/1/10, Joey Kelley <[email protected]> wrote: >>>>> I'm with Kyle on that one.... >>>>> I had mine redone by a local guy, trying to start a name for >>>>> himself in the upholstery business - it looks less like a 80s Honda >>>>> seat now, more like an ATV, but I actually prefer it, looks cleaner. >>>>> -Joey >>>>> >>>>> On Wed, Sep 1, 2010 at 8:58 PM, Kyle Munz <[email protected]> wrote: >>>>>> Um, that's way over my "cut up the couch and steal the foam" level. :) >>>>>> >>>>>> -Kyle >>>>>> >>>>>> >>>>>> On Wed, Sep 1, 2010 at 7:00 PM, Kurt Nolte <[email protected]> >>>>>> wrote: >>>>>>> >>>>>>> So, let me bounce some stuff off you guys, since the specs listed on >>>>>>> the DIYmotorcycleseat.com site don't seem to be standard with the >>>>>>> suppliers I'm looking at. >>>>>>> >>>>>>> Since neither of my foam inserts are really in any decent shape to put >>>>>>> back on the bike (lots of dry rotting and cracking), I'm looking to >>>>>>> use one of them as a basic shape guide and just making something new. >>>>>>> DIYms suggests a high density polyethylene closed cell foam as a base >>>>>>> layer, but I'm not finding much info on the ILD and compression >>>>>>> modulus specs on supplier websites. >>>>>>> >>>>>>> I do have specs for "PSI (% deflection)" which seems to be how much >>>>>>> PSI (usually 4-9) it takes to hit (usually 25%) a certain compression. >>>>>>> I don't know if this is comparable to ILD; anyone here know? Anyone >>>>>>> here a materials engineer? >>>>>>> >>>>>>> Thanks! >>>>>>> -Kurt > > -- > You received this message because you are subscribed to the Google Groups > "Nighthawk Motorcycle Lovers!" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/nighthawk_lovers?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en.
