brainfart

Maybe off-topic, and I have never heard of these being used on planes, but I wanted to point out the availability of gasoline-fuelled automobile heaters. They can be installed in pretty much every car and are used to heat up the car interior and engine before driving. They are usually installed in the engine compartment, heat up and circulate the coolant and switch on the ventilation so your car and engine will be warm, comfy and ice-free during winter before operation. They aren't very heavy and large and fuel consumption isn't very high either. Installing one of those might actually be an alternative to complicated and error-prone engine coolant heating. They are manufactured in huge numbers and are proven in automobiles, mobile homes, busses and boats. http://www.parkingheater.com/ http://www.parkingheater.com/products/small-car.html

Well, I am confused by the use of imperial units (metric makes so much more sense), but indeed, at a higher elevation water will boil earlier due to the reduced outside pressure. Water boils at 100°C at normal atmospheric conditions (vapor pressure thus being 1 bar) and will produce an additional 1 bar at about 120°C. At reduced pressure it will boil earlier since its vapor pressure equals the outside pressure at a lower temperature. A cap which releases pressure at 13psi above outside pressure will therefore release pressure at a lower temperature. (Does that make sense?)

> Respiration does add a lot of moisture to the air. When you run the widshield > defroster in a car, the airconditioner actually runs at the same time to reduce > the humidity in the heated air. Cold air is "dry", it doesn't contain a whole lot of water to begin with. The colder it is, the less water it contains. When it heats up the relative humidity drops even more. If fresh air is getting into the cabin through the heater then some very dry air is coming your way. Every commercial aircraft passenger knows this, the air in airliners is always very dry for the same reasons even though there are a lot of sweating and breathing human beings with you in the same confined space. You cannot compare this to a car where recirculation is used during cold and damp weather.

> hmmm...a CNC'd larger (than EZ), rounded, Berkut like fuse out of foam, > standard fuse layups...thow in bulkeads & longerons...hmmmmmm.... If you go that far, why not go a little further: make it a plug, build a mold, and then invite people to use that mold at your place for a modest fee to get some of the invested money back...

> .91Width*.91Length*.91Height = .75 total size and weight Weight doesn't scale unless you use glass and foam and other building materials that are only 91% the weight of the original. Which you can't, because the strenght requirements for many parts will still be the same as the original.

> btw Could you use quote tool next time it will be easier to read for others. That's how I learned it back in the mid nineties on usenet, not going to change that now

> Some people think that honeycomb and wet/hand layup isn't the best > connection (even if you use vacuum bag), I cannot agree with that at all. If you're in doubt that the bond between your laminate and the honeycomb is sufficient (e.g. due to not enough epoxy when using carbon fibers) you can use a single, thin, very lightweight layer of open weave glass or other material which will act as a resin storage and allow proper laminate to honeycomb bonding. > My dream to have digital camouflage painting or grey. Isn't that kind of dangerous, making your plane intentionally invisible? > The biggest adventage (in my opinion) for this resin is heat distortion temperature 150C Laminating epoxies with Tgs that high and higher are available, too. Unfortunately there's a trend in epoxy resins, the higher the Tg the more viscous the resin will be. The reactive diluents which are added to the base resins to reduce their viscosity in order to make them usable as laminating resins also reduce the Tg of the final product. Such high Tgs also require post curing at elevated temperatures, you cannot make parts with high Tg by curing them at room temperature or slightly above. If you want a high Tg, your parts needs to be cured at approx. 30K below the desired Tg. I assume that bonding of vinylesters isn't that simple once they are fully cured. I also assume that vinylesters require post-curing to reach high Tg. Anyone? > Vinylester works well for vacuum infuision methods but it isnt the best idea to use them with Carbon or Kevlar. Why not? > Rohacell foam (but it's probably the most expensive foam on the market.) If you do not absolutely need its excellent physical properties, use another foam. There are cheaper foams with great properties. I hope prices will go down soon though, a second manufacturing plant opened in the US last year, now there are two (the original one being in Germany). > compare Derakane mechanical properties with MGS mechanical properties, > the biggest differnece is in heat distortion temp 70vs150C Make that 90-110°C, when properly post-cured. Considering that many planes are being built with West System (Tg around 50°C)... > I'm trying to remember which system it is that has a tendancy to absorb > moisture. I thought I remembered it as being Vinyesters. Actually it's the epoxies that absorb more moisture. Apart from reducing their Tg a little that's not necessarily a bad thing, moisture makes them less brittle. Mechanical properties just need to be determined on equilibrizised (??) samples if you want real world numbers, not oven-dried ones. > you can't use Vinylester with blue foam, because it will disolve blue foam. Yes, it's still one third styrene and will stink accordingly when working with it. (There are many jokes about polyester workers who have breathed too much styrene for way too long in the fiber reinforced plastics industry ) I also have doubts about proper curing in honeycomb applications, polyesters often don't cure fully due to the inhibiting properties of styrene vapors in voids, same might be true for vinylesters? It also shrinks just like polyester when it cures.

You bought a complete replacement and it's still not working? Sounds like some sort of operator error. Does it work on your workbench, when it's not built in?

When composite repair work is done on non-experimental planes, a sample of every mixed batch of resin needs to be taken over here. A small blob is poured on a piece of paper, project, name, date, time are recorded and it is then filed with the paperwork describing the repair job.

> with low thermal conductivity of 0.1 W / m / Deg.C That might be true, but since the insulating paint layer is very thin it won't insulate all that much. Basic physics. I'm not convinced.

Have you been to Darois? Nice builder support program they have going on there. Had a look at the MCR01 two years ago. Nice plane! > epoxy glue called AXON Yep, they still use that stuff. While flox is widely used for gluing airplane stuff, specialised adhesives often have better adhesion due to some of the ingredients used. Rock hard bond lines aren't necessarily the best way to glue things together, in many cases a little flexibility will produce a better bond which can absorb more energy.

> Airbus is headquarted in Toulouse Yes. And EADS, which owns Airbust, is headquartered in The Netherlands...

> (Boeing and those cheese-eaters across the Atlantic) It's always nice to see these kind of prejudices prevail even on fora where people are expected to have above average mental capabilities, you SUV-driving burger-eater. (What's this thing you people have with the French???) Besides, just to point out the obvious, Airbus is not French.

> weight came to 97 lbs. Weighed the AC before painting, all preped for paint > and weighed after completed. Painted AC weighed +23 lbs. Overspray and volatile solvents.

Webmaster: snow@speedcanard.de Ok, I'll stop now. Hope the right addy is somewhere in my posts.

Online phonebook says there is only one "Holger Wieck" in that town: Private address: Holger Wieck Würzburger Str. 22 86720 Nördlingen Germany Business address: Holger Wieck Raiffeisenstr. 4 86720 Nördlingen Germany phone:+49 9081 40 00 holger-wieck@gmx.de http://www.holger-wieck.de http://www.wieck.biz/ Private homepage: http://www.holger-wieck.de/hw/index.php (diving, skydiving, car racing, but no canards being mentioned)

Using server whois.denic.de. Query string: "-T dn,ace -C US-ASCII speedcanard.de" % Copyright ©2008 by DENIC % Version: 1.10.0 % % Restricted rights. % % % Terms and Conditions of Use % % All the domain data that is visible in the whois search is protected % by law. It is not permitted to use it for any purpose other than % technical or administrative requirements associated with the % operation of the Internet or in order to contact the domain holder % over legal problems. You are not permitted to save it electronically % or in any other way without DENIC's express written permission. It % is prohibited, in particular, to use it for advertising or any similar % purpose. % % By maintaining the connection you assure that you have a legitimate % interest in the data and that you will only use it for the stated % purposes. You are aware that DENIC maintains the right to initiate % legal proceedings against you in the event of any breach of this % assurance and to bar you from using its whois query. Domain: speedcanard.de Domain-Ace: speedcanard.de Nserver: ns3.kasserver.com Nserver: ns4.kasserver.com Status: connect Changed: 2007-08-01T01:06:23+02:00 [Holder] Type: PERSON Name: Holger Wieck Organisation: Praxis im EGM Address: Raiffeisenstr. 4 Pcode: 86720 City: Nördlingen Country: DE Changed: 2008-11-04T11:50:14+01:00 [Admin-C] Type: PERSON Name: Holger Wieck Organisation: Praxis im EGM Address: Raiffeisenstr. 4 Pcode: 86720 City: Nördlingen Country: DE Changed: 2008-11-04T11:50:14+01:00 [Tech-C] Type: PERSON Name: Werner Kaltofen Organisation: Neue Medien Muennich GmbH Address: Hauptstrasse 68 Pcode: 02742 City: Friedersdorf Country: DE Phone: +49 35872 35310 Fax: +49 35872 35330 Email: info@all-inkl.com Changed: 2007-10-09T21:15:45+02:00 [Zone-C] Type: PERSON Name: Werner Kaltofen Organisation: Neue Medien Muennich GmbH Address: Hauptstrasse 68 Pcode: 02742 City: Friedersdorf Country: DE Phone: +49 35872 35310 Fax: +49 35872 35330 Email: info@all-inkl.com Changed: 2007-10-09T21:15:45+02:00

No. The achievable Tg for the slow hardener is actually 15 degrees centigrade higher than the fast hardener, IF you cure it properly at elevated temperatures.

There's a reason Rotax engines (especially the 91X) dominate the market here in Europe, and that reason certainly isn't price related.

Congratulations!

> How can I determine the suitability of this product? Is there a test? In some countries epoxy manufacturers can submit their products to the local FAA equivalent and have them approved. That's how the MGS resins got their "suitable for gliders and powered aircraft" rating and good reputation. The requirements for the German rating are mentioned in some MGS datasheets (MGS used to be a German business, and several other European countries have adopted the German standards). Similar testing of resins is done by other organisations for other purposes, e.g. for boat building, wind turbine blade manufacture, railroad use etc. While most resin systems easily fulfill the boatbuilding test requirements, only very few get approved for aircraft use. I seem to remember one of the critical tests involved simulating the bending of a part made with that resin some 2*10^6 times, that's where many resins with otherwise great mechanical properties fail. Other requirements involve the usual mechanical properties at different temperatures, Tg requirements and also some dynamic testing.

> I wonder how safe you are flying an airplane with an aviationized snowmobile engine. The 912 and its variants are NOT based on snowmobile engines!

To completely cure epoxy resins and reach a high Tg you need higher temps than just 38°C/100F. Unless you use the fast West System, whose Tg isn't much higher than room temp anyway... The MGS 285 resin for example absolutely requires curing at higher temperatures to reach its full potential. Same is true for ALL other resins using such slow hardeners. Curing a part made with epoxy with 90 minutes of pot life at 80-100F will leave it right in the middle of the brittle B stage.

You can build a box out of styrofoam and sheetrock and heat it with lightbulbs, as others have said before. Doesn't necessarily need a floor so you can put it over the parts. Also invest in some sort of electronic thermostat so you can keep the temperatures at exactly the desired level and even ramp the temperature up at predetermined rates. I used to improvise such a heating chamber using the corner of a room and three pieces of styrofoam, two lightbulbs, a dimmer, an electronic kitchen thermometer (5 bucks) and a PID temperature controller (dumpster diving, optional and not really needed). Worked very well.

Then why don't you ask Mr. Rutan to release the whole shebang into the public domain?