http://www.foamular.com/assets/0/144/172/174/98cf58e1-c3d2-4b6c-beb5-2063215bea18.pdf

Shows density

On May 19, 2018 3:13:01 PM UTC, "StoneTool owly@ttc-cmc.net [harryproa]" <harryproa@yahoogroups.com.au> wrote:
|      The PDFs do not show density anywhere I can find..   The Dow web
|page, unlike the other Dow web page where I previously looked does show
|
|the densities of the foams as being from 1.3 PCF to 3 PCF for the
|Highload 1000.  The foam I've been experimenting with that I thought
|was
|2 PCF is listed as a type IV at only 1.55 PCF.   It's worth noting that
|
|the compressive strength to weight ratio is NOT linear.  Dividing
|compressive strength by density in PCF, we get 22 for the 40, 29 for
|the
|60, and 33 for the 100.   Imagine what the compressive strength of a 5
|PCF XPS would be.... probably in excess of 200 psi, and right in the
|ballpark with divinicell H80 (218).     H-45 shows 87 psi.   The
|Highload 60 is the same density as H35, which has a compressive
|strength
|of 65.3 pounds per square inch compared to 60 for the XPS.
|       When looking at an application like a deck, the same density of
|XPS versus Divinicell has only slightly less compressive strength.  
|The
|other mechanical properties are not particularly relevant in that sort
|of application.
|
|    As I can get the 1.5 pcf XPS insulation foams from local yards, and
|
|they are from the same manufacturers, it is likely that the 3 PCF foams
|
|could be special ordered in full bundle quantities, and ordered that
|way
|on a stock order, it probably would be economical.
|
|     The ability to flex and recover from deformation of pressure and
|impact is more important than just compressive strength. XPS is
|probably
|better in a crush structure in the bows than something like divinicell
|assuming it is not as elastic. Crushing or crumpling of a structure
|absorbs energy better than elastic deformation which stores energy and
|rebounds.
|
|     I would personally have no hesitation whatsoever in using this
|higher density XPS in bulkheads, beams, decks, and other upper
|structure.....   a from a structural standpoint.  Time, labor, and
|process might make the difference.  If for example it does not lend
|itself well to infusion, resulting in more labor and resin use that
|could be a factor.  Availability in the desired thickness might be
|another factor.  I can almost guarantee that it won't be a normal stock
|
|item at any supplier within hundreds of miles.   I would expect that a
|city 500 miles from my current location would be the nearest likely
|source, based on past experience.   I would expect to be able to get it
|
|reasonably only in pallet quantities, but I would also expect the cost
|to be in the range of 10% of the cost of Divinicell.    5 or 6K worth
|of
|foam (Divinicell) in the context of building a 30' catamaran,
|considering that it is core for the entire boat, really is not a big
|price.  If half that were 100 pcf XPS, both cost and weight go down. 
|Cost from 6K to perhaps 3500.   A savings of 2500 dollars maybe.    If
|the intelligent infusion process doesn't work well with XPS, that
|changes the equation.   Knife cutting. drilling, surface prep like my
|flash blasting, adding a flow media, etc............   It all adds to
|time and cost, and whittles away at that 2500 to the point that it
|might
|not work out at all.   Weight savings in foam for 25 sheets would only
|amount to about 89 pounds..........about a 5% increase in
|payload.....another anchor, more chain, an additional battery........
|take your pick.     89 pounds in the context of a light catamaran is
|not
|an insignificant savings.
|
|
|H.W.
|
|
|On 05/18/2018 10:33 PM, '.' eruttan@yahoo.com [harryproa] wrote:
|>
|>
|>
|> |Nor have I seen the foams you mention anywhere................ 
|> Interestingly neither Dow or Owens Corning list the density for any
|of
|> these two families of foams.
|>
|> Yes they do.
|>
|> http://www.foamular.com/foam/products/foamular-1000.aspx
|>
|http://www.foamular.com/assets/0/144/172/174/98cf58e1-c3d2-4b6c-beb5-2063215bea18.pdf
|>
|>
|https://www.dow.com/en-us/building/industry-updates/top-6-questions-asked-of-rigid-insulation
|>
|> If you can't locate a supplier locally, try harder.
|>
|>