I just checked on the price of extruded polystyrene at Whitecap- it is $76 per sheet (2" x 4' x 8'). Does that sound anything near appropriate? It sounds about 4 times as expensive as I would have thought! Bill Masquelier
> To: krnet at list.krnet.org > Date: Sat, 22 Aug 2015 20:29:04 -0700 > Subject: Re: KR> Foam, peel ply and tank vents... > From: krnet at list.krnet.org > CC: billmasq at hotmail.com > > Colin > I was avoiding extruded polystyrene since I couldn't find it here in Southern > California but since you brought it up again I have found that it is > available near here (near French Valley) in Temecula at Whitecaps: > http://www.whitecap.com/shop/wc/building-materials/insulation-materials/extruded-polystyrene-insulation > > so if anyone else here in SoCal needs it it does exist!! > Thanks Colin and best on your trip over the Bearing Straits and beyond :) > BillM > > > To: krnet at list.krnet.org > > Date: Sat, 22 Aug 2015 23:23:19 +0100 > > Subject: KR> Foam, peel ply and tank vents... > > From: krnet at list.krnet.org > > CC: colinhales at hotmail.com > > > > Several thoughts gents, > > Bill, high there, I'll write soon, but continuing, unless you want to use > > wing tanks, remember that Styrofoam is a much better product than Urethane > > foam which I would NEVER ever use. > > It crushes and has no rebound unlike polystyrene foams, so if you drop > > something on your wing skin or someone kneels on it, the Urethane foam > > crushes and a void is left behind the glass as it pulls away from the glass > > skin. Styrofoam has a bit of bounce and give and this doesn't happen. Also > > Urethane is open cell and you have to add the heavy layer of Micro balloon > > slurry to seal it before adding the glass cloth and trying to wet it out. > > If you want to still use Urethane foam, you can now get a closed cell type. > > Any open cell foam can and will absorb water over time and you never know > > about it. Even white polystyrene foam is not water tight enough and water > > gets between the molecules over time, unless it is well sealed. > > So personally open cell Urethane foam is just a bad idea all round. > > I've squeezed water out of Urethane foam on a hovercraft, if you get water > > on your plane with open Urethane foam, it goes in and you will never get it > > back out. > > If you want to use stub wing tanks, and have the outer panels dry, then by > > all means use Urethane foam for the stub wings but use Styrofoam for the > > outer wing panels. > > Here is an article of other types of Styrofoam. The don't like the > > standard blue foam much but they are hot wiring it. We are not. > > https://www.flyingfoam.com/content/why-we-hate-blue-foam > > > > A typical good supplier of blue foam I would say is, > > http://building.dow.com/en-us/products/styrofoam-brand-residing-board-us-only/?sc_itemid=320ebb4f-f0ab-47e7-a5b6-334429f8dec8 > > Next, peel ply. > > A good cheap source of peel ply is called 'Ceconite', you know the stuff > > they stick on fabric aircraft? Go grab a load of off cuts from a fabric > > shop or buy some, its as good as the peel ply you can buy, no silicones > > obviously, and it comes in 6 foot wide strips in case you want to cover > > large areas. It comes in different grades of light or heavy that will give > > you different surface textures depending if you want to add on to the glass > > or simply have a smooth surface ready for applying fillers and top coat > > paints. > > Fuel, > > As for fuel sitting in vent pipes. If you can see the fuel sits in the pipe > > or presume it would do in the dip, that is fine . The air will bypass the > > fuel so don't worry about that, there is 'little' to 'no' head of pressure > > in the pipe, any slight difference in pressure will move the fuel along. My > > only comment on this is that you better make sure the vent pipe you are > > using or going to use is happy to have avgas or mogas or regular gasoline, > > whatever you intend to use sitting in it for long periods of time. Some > > nylon pipes go brittle when immersed in fuel for long periods. Just food > > for thought. > > Sorry I'm going to miss the Kr gathering, I went through Mc.Minnville a > > week or two ago on my way up to Alaska. It is a brill place to visit, town > > is lovely, the puce Goose and the rest of the Museum is top rate and > > Graham, Northwest Air Repair is a great host, so please pass on my regards. > > I'm now in Anchorage, eyeing up the Russians and seeing what can be done to > > continue. > > Cheers Colin. > > _______________________________________________ > > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > > please see other KRnet info at http://www.krnet.org/info.html > > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > > options > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options
