Glass/Foam VS. Aluminum

[Jon Matcho]

There is a another reason to stay away from MEK. Not only are the fumes extreemely hazardous to your health to breath in, solvents are obsorbed through the skin! Ever read the warning label on a can of MEK? BAD STUFF!!

I understand acetone will allow epoxy to be absorbed through the skin as well, but is less toxic than MEK. I use it, but will have to try your 50/50 mix of denatured alcohol/laquer thinner.

 

I also use vinegar as much as possible -- cleaning skin, squeegees, etc., but it's not good enough for knocking uncured epoxy off a brush.

[David Clifford]

I understand acetone will allow epoxy to be absorbed through the skin as well, but is less toxic than MEK. I use it, but will have to try your 50/50 mix of denatured alcohol/laquer thinner.

 

I also use vinegar as much as possible -- cleaning skin, squeegees, etc., but it's not good enough for knocking uncured epoxy off a brush.

I have aso used the Replaceatone sold by AS&S. It works about as well as vinegar so save your $$. Vinegar is a good pre cleaner,,,then finish up with the mix.

[mplafleur]

Geez, and I used to wash my hands in that stuff when I worked in the fiberglass factory as a teenager.

[mak790]

John PA

I had similar feelings like you about cracks and delamination after I read Long Ez POH (page 46) you can download it here

http://www.ez.org/downloads.htm

 

But other way, personally I've never ever heard about any fatal or nonfatal accidents caused by delamination you can check all long ez accident reports here

http://www.ntsb.gov/ntsb/query.asp

 

And the last thing I believe that about 90-99.9% of accidents are caused by engine troubles (loss of engine power) and pilot errors.

 

Mak

[John PA]

Jon Macho

I'm still looking on the net for that video of Rutan jumping on a wing. Gotta see that! Thanks for the foam info.

 

Argoldman

Solid points on the extensive use of composites in GA aircraft.

 

mac790

Thanks for the long ez POH tip. Seems like delaminations are perfectly repairable.

 

And I will be very careful about the allergy issue. I remember hearing that before.

 

 

Has anyone here had to scrap a glass plane, or know anyone who has had to scrap a glass plane because it was delaminating, or cracking? How about massive damage due to heat or sun? Experiences?

[Marc Zeitlin]

Has anyone here had to scrap a glass plane, or know anyone who has had to scrap a glass plane because it was delaminating, or cracking? How about massive damage due to heat or sun? Experiences?

At least within the canard composite community of approximately 2000 - 3000 flying aircraft, it's never happened. That I'm aware of. From reading all the CP's and COZY newsletters and following the on-line communities for the past 12 years.

 

EVERYTHING is repairable.

[jpolenek]

I'm still looking on the net for that video of Rutan jumping on a wing. Gotta see that! Thanks for the foam info.

 

It is in the video Building The Rutan Composites which is included with Cozy MK IV plans. (Doesn't look like Aircraft Spruce sells it on its own.) It's a great video, in which Burt Rutan and Mike Melvill demonstrate the basics of composite construction. It looks very dated, but that gives one an appreciation of how long these techniques have been in use.

 

Joe Polenek

[TMann]

It is in the video Building The Rutan Composites which is included with Cozy MK IV plans. (Doesn't look like Aircraft Spruce sells it on its own.) It's a great video, in which Burt Rutan and Mike Melvill demonstrate the basics of composite construction. It looks very dated, but that gives one an appreciation of how long these techniques have been in use.

 

Joe Polenek

To Marc & Joe's point:

The building process has worked so well and is so reliable that Burt was able to build a company from it.

[argoldman]

To Marc & Joe's point:

The building process has worked so well and is so reliable that Burt was able to build a company from it.

 

Ya, but he was just reaching for space!!!

[jpolenek]

I'm still looking on the net for that video of Rutan jumping on a wing. Gotta see that!

Coincidentally, the video clip you want to see just showed up on YouTube.

 

 

Imagine that!

 

 

Joe Polenek

[mak790]

Coincidentally, the video clip you want to see just showed up on YouTube.

Thanks for that.

Good Job

btw Mike Melvill false-started first attempt.

Mak

[John PA]

Coincidentally, the video clip you want to see just showed up on YouTube.

 

 

LOL!!!!!! Thanks a bundle. That was great!

 

Thanks again to everyone. I am feeling very confident about glass. If I had to use metal to get a good aircraft, I probably would not build. I have a set of Sonex plans here at the house (borrowed), and while it looks like a perfectly good airplane, building it does not look like much fun.

 

John

[Big Steve]

Working on my second composite plane the only down side I find to composites is that when you are doing a large layup you cannot quit. You have to finish or you could ruin the whole part. I did the bottom of my longeze all by my self I started at 8:00 am and finished at 12:00 am that night. That plane is now 23 years old and is still flying. So yes composites do last a long time. I think it is a lot easier to learn how to build with composites than metal or tube and fabric. So quit talking get down and buy your plans and start building your dream!!!! STeve:D

[Edge 513]

Didnt know where to post this, but it is from the new AOPA refurbishment airplane [anArcher] that talks about sound deadening efforts in an old airplane. I could help but think- "why not just own a composite?..they are built out of this stuff anyway". The first part of the article was about the fatigue of flying in an older aluminum airplane due to the noise.

Quoted:

"Oxford does things a bit differently. When an owner decides to have new sound-proofing material installed, the first step is to rip out the old stuff. Horowitz said most owners would be amazed at the condition of their airplane. If the insulation isn’t damp or full of mold, it’s piecemeal, or in some cases, completely missing. After removing the old material, Oxford coats the inside of the skin with an impregnated vinyl. Horowitz said it helps to distribute the sound waves. Oxford will sometimes illustrate this to customers by putting them inside the airplane and tapping on the fuselage. Without the vinyl, the tap will ring through like a bell. But after the vinyl, said Horowitz, the tap is more like a thud.

 

Next comes Oxford’s special sound-proofing material. The workers take a layer of fiberglass made specifically for sound attenuating, a dense layer of foam for low-frequency sound waves, and then another layer of the fiberglass. That sandwich of materials is then heat-sealed in Mylar to make what resembles a pillow or a couch cushion. The entire inside of the airplane is filled with the custom material, which is numbered for easy removal and reinstallation later.

 

After the sound-proofing material, the sidewalls are addressed. Though each manufacturer does it a bit differently, the Archer’s sidewalls were made of cardboard. The flimsy material retained moisture really well—something it wasn’t designed to do. So Oxford took the initiative and created custom plastic sidewalls that will be much more durable for the sweepstakes winner. That plastic is also covered with an extra layer of foam to help with sound attenuating, and let’s face it, the sidewalls will look better too."

 

I loved the cardboard part...gotta like those lightweight type materials...don't cost much either! People that visit my project are encouraged to thump the side of my fuselage HARD, [thud] and then go crunch a soda can in the recycling bin...They almost always remark, that that must be an unfair comparison, or that my fuselage MUST weigh a ton. So I hand them a decent sized part like the landing gear cover, or a seat cover, and they look at the pop can again. Most dont realize what aluminum planes are made of. They do seem to agree the solidness of the composite seems preferable. Often many want to discuss the differences of a Cessna or Piper that they rode in or flew in or are flying. I don't know why some have such an affinity for aluminumb....but I draw the line at quality grade cardboard- the manufacturer will not be using cardboard in this aircraft.

[Big Steve]

Edge:

 

I think the reason so many people own aluminum planes is that is all the manufactures will make. It takes a special kind of person to make there own airplane out of composite or aluminum or wood. All of you builders and flyers considere yourself special. STeve

[macleodm3]

I have no data to back up this thought. Here is my unfounded thought. Many of the things we live with that are durable and last for years (automobiles, appliances, extension ladders, tools....) are made from metal. To me, plastic stuff still seams "cheaper" or weaker (even if its not).

 

Many people question the plastic bodied Saturn autos, but hey they seem to be doing fine.

 

Airplane manufacturers are set up for metal production, but people also trust metal, as evidenced by its history for the last bit of recent hisory.

[Neverquit]

Many people question the plastic bodied Saturn autos, but hey they seem to be doing fine.

 

I had a VUE. That stuff's incredible. Avoided a road rage incident (two other guys) on ice and tagged the rear end of another car. The steel hood was curled under and the grill area puckered like someone eating lemons. I got out and popped out the grill area by hand. It went back into place. The rood needed replacing. They're making the VUE's from metal now because it's cheaper. Funny what we percieve as cheap and what is truly cheaper.

[argoldman]

I had a VUE. That stuff's incredible. Avoided a road rage incident (two other guys) on ice and tagged the rear end of another car. The steel hood was curled under and the grill area puckered like someone eating lemons. I got out and popped out the grill area by hand. It went back into place. The rood needed replacing. They're making the VUE's from metal now because it's cheaper. Funny what we percieve as cheap and what is truly cheaper.

They may be cheaper to make, but the repair on metal is significantly more involved and expensive. The auto manufacturers must support the body shops who are buying parts at prices multiple times of those charged in the original auto. Some think that the Rotary engine was nixed because of the relative ease and pecuniary minimalism of repair (low cost).

 

While talking about glass cars, don't forget the Corvette. I believe that the Avanti was also made of glass. All of the original GM vans (silouhette, Lumina,Trans port thing were also made of plastic/glass. Don't forget the Feiro!

 

However the Saturns, Corvettes, Avantis, Fieros and GM vans were made of solid glass/plastic panels, usually gun shot into molds (except for Fiero and Saturn probably thermo molded plastic), not composite, much like boat hulls. The parts were quite heavy. The sandwich construction we use gives a much better weight/strength ratio.

 

As we know, usually a sheet of aluminum is stronger and less flexible, and actually lighter than an equally thick sheet of fiberglass/epoxy-polyester resin. It is only when the fiberglass is used as the "bread" of a sandwich around, say for example foam filler, that all of the benefits that we enjoy are enjoyed

 

 

Enjoy