bgordon's 5 week cardboard & fiberglass build

[Shadow Catcher]

How ethnocentric of me, I did not even look at your country of origin. I figured you had used cloth rather than chopper gun, that raises the level of complication and just plain grunt work a great deal.
While there are things available here in the states they may be difficult to find and not available in small quantities. Much of what I was doing was pure speculation. What we have coming was the best, easily available, Filon skin aluminum frame etc.
congratulations on what you have created and we hope to see pictures of you all and your country. Challenges you face and joys you find.

[Cliffmeister2000]

This photo is for Cliff (Meister). The hatch, complete with missing gas struts! (that was in the plan, but the time did not allow it).

Fortunately the hatch is so light that my daughters can lift it (to my wife and my surprise).

Good looking Teardrop, and great looking family! I assume your wife is the photographer?

I really like your graphic. Is that just paper under the final coat, or did you have a decal made?

I'm betting you have some great photos of your trip! If you wanted to share some of those, I'll bet no one would object!

[glassice]

[/quote]You can also see in the picture above that I am paranoid about fiberglass and safety, especially around children. My daughter wanted to remove some dust, but I agreed only if she wore the respirator.
[/quote]


The dust is worst than asbestos I now make my workers change what they where be for they can go home I don't want the dust to go home to there Kids
And I am sure you know that the body will drink up M.E.K.P and go right to the liver I seen a lot pass a way from this. Sad to say this is why so many fiberglass worker die from
Very nice trailer

[bgordon]

...that raises the level of complication and just plain grunt work a great deal.

Yep, you can say that again. The sanding was definitely the most frustrating part of the build.

Good looking Teardrop, and great looking family! I assume your wife is the photographer?

Thanks, and thanks! Yes, my wife took the photos. She LOVES taking photos, and took more than 600 on this trip alone (I won't bore you with all of them though!). Because of her love of taking photos, I actually have some photos of the build, as I have shared with you already. When we are on holiday, my wife takes the camera along everywhere. That is why I am in most photos with the kids. I love taking videos, and in our family videos she is always with the kids!

I really like your graphic. Is that just paper under the final coat, or did you have a decal made?

No, no paper. It is actually a digital vinyl print. I designed it with Inkscape (open source) (http://www.inkscape.org/) (one for each side), and had it printed at a digital print shop. Both (on good quality vinyl) cost me less than $20.

And I am sure you know that the body will drink up M.E.K.P and go right to the liver

Yep. I keep those things away from the kids, and are extremely careful when I handle it myself!

[bgordon]

I'm betting you have some great photos of your trip! If you wanted to share some of those, I'll bet no one would object!

Yep. Here are a few:



In the photo (above) you can see all four of us, if you look carefully. I am taking video while my wife is taking pictures.



The Northern Cape is home to the Kalahari desert. It is the driest part of South Africa. That is why you'll find strange trees, like the 'Kokerboom".



Once a year the desert comes alive with the most amazing flowers. This is only the beginning of the flower season, and pales in comparison when the flower season really starts.

(Do a google search for "Namaqualand Flowers" and you'll see the most amazing images!)



This is what the flowers look like from up close.



Here we are at the West Coast of Port Nolloth. The sea water is almost freezing due to the water coming from the South Pole. This is in stark contrast to the eastern seashore where the water is really warm, as it comes from the north. (South Africa divides two oceans, the one is icy (Atlantic Ocean), and the other is warm (Indian Ocean)).



The caravan park (above) is right on the beach, but is almost deserted, because it is the rainy season and usually very cold. We were fortunate to have lovely weather.



Back in the desert - In 1999 we were fortunate enough to visit the Grand Canyon in Arizona. Since then I always wanted to see the second largest canyon too. Well, here it is - the Fish River Canyon in Namibia. Very difficult to get to. Gravel roads only. Now I can say I've seen all three major canyons in the world (The Blyde river canyon is the third largest in the world, and is also situated in South Africa, close to the Kruger National Park).



Proof that we were there...



A lovely motel right in the middle of the desert.



Back in civilization, at the world's longest date palm lane. Just over 1km long. (Situated in Upington).



A small town called Kathu is close by a massive iron ore mine. Here they exibit some of their trucks. Yes, it is MASSIVE. Interestingly enough it runs on electricity (four electric motors - one for each wheel, as it provides more torque than an internal combustion engine can deliver!)



You might have heard of the red sand of the Kalahari desert. Here you see it for yourself. And yes, the sand is really red - the photo has not been touched up in any way...

[Cliffmeister2000]

Awesome photos, Barrie!

It looks like you had a grand time, building memories for your children!

Here's a recent one of the Grand Canyon, where I was lucky enough to get a shot of a condor.

[kennyrayandersen]

great pics!

I'd agree with you though about using something else besides cardboard for the sides -- the shear properties are just so low. Foam (pink or blue) would be a good choice with at least a few layers of fiberglass fabric and good prep on the core is important, but it has potential.

[Woodstramp]

bgordon,

Outstanding job! Like the idea of the fiberglass.

Been thinking along those same lines. Glass cloth/resin over a foam insulation instead of cardboard. (no access to a glass chopper)

I helped an old pilot build one of those Burt Rutan kit planes (Vari-eze) back in the 80's. That's all those things were made of. I think this could be applied to these little campers. If your cardboard works that amazingly well, then a foam/resin/glass cloth shell should be like a tank.

Oh, a young'n here told me how to pronounce South Africa like you natives. "Suta-freeka"....is that correct?

[kennyrayandersen]

bgordon,


Been thinking along those same lines. Glass cloth/resin over a foam insulation instead of cardboard. (no access to a glass chopper)

You could always lay down fabric rather than shooting on chopped fiber -- it's stronger than chopped fiber although there is a bit more labor. That's how I'm planning to do it anyway...

[starleen2]

Photo above: old school technology: chop strand and polyester resin

Hey now - throw the yellow flag! time out. What's this about fiberglass resin? Where are all the epoxy folks (and you know who you are) who are ready to tout the advantages of epoxy and how BRITTLE resin is? surely this thing is going to fall apart because he used resin instead of the better and more expensve epoxy! enough of the rant - dude that is some well laid glass work and an excellent concept of materials.

[Changer]

This is awesome!

Now, question for the fiberglass experts who are mentioning using foam- won't polyester resin disolve foam?

[eamarquardt]

This is awesome!

Now, question for the fiberglass experts who are mentioning using foam- won't polyester resin disolve foam?

You have to use the right kind of foam. Virtually all foam boats and surfboards are made with polyester resin.

Polystyrene foam is "eaten alive" by polyester resin and you have to use epoxy with polystyrene foam (or at least seal the polystyrene with epoxy before using polyester resin).

Cheers,

Gus

[Changer]

So... non polystyrene foam is called what, if I wear searching for a local supplier?

This design is inspiring. I'm MUCH more confident of my ability to deal with cardboard and chemicals than woodworking tools.

Oh, and other question, how is strand fiberglass like that applied? Put into resin and smoothed on,or what?


Cait

[eamarquardt]

This article should explain a lot:

http://www.boatdesign.net/articles/foam ... /index.htm

You'll probably have to order the foam from a supplier and have it shipped to you. Never seen it at a "big box" store.

I believe the fellow used a "chopper gun" to lay his glass. From what I've seen a chopper gun is not something the typical handyman will have lying around. Pretty expensive and geared towards high production. Also the layup isn't as strong as one using cloth.

Hope this helps.

Cheers,

Gus

[kennyrayandersen]

Fiberglass isn’t a resin. The resin is the matrix material that keeps all of the fibers in place so that they can react the load. The matrix itself can be either polyester or epoxy (or a few other things). Either will work and each has advantages. Polyester is cheap; epoxy is not. Epoxy is higher strength and more stable and is used in the aerospace industry along with high-performance marine applications whereas Polyester is mostly used in lower-cost marine applications (think recreational boating).

Unfortunately, Polyester eats the cheap home depot foam… oops. So, as Gus states you have to use a ‘real’ structural foam. This kind of foam is used in the aerospace and high-end boat building and is REALLY expensive; so much so, that it is actually cheaper to bite the bullet on the epoxy resin/fiberglass and use the cheap foam than it is to save money by using the polyester resin and expensive foam. I looked into it at length because I thought using the epoxy for the tear was a bit overkill (polyester would be strong enough as a resin – you still have the fiberglass fibers to get strength) and I knew polyester resin was cheap. But when I started checking out the ridiculous prices of the compatible foams, it became a non-starter (maybe I just couldn’t find a cheap source…).

One thing that should be noted for chopped fiber (the kind you spray on to save labor). It isn’t as strong so you need more of it. It’s not that the chopped fiber won’t work; it’s that the fibers are shorter so the weaker resin is doing more of the work and so more chopped fiber is required to carry the same load. More chopped fiber also means more resin to hold it so the overall weight goes up. As has been discussed several times before, the teardrop loads are not that high, so it’s not a big issue – as far as strength is concerned.

The easiest way to duplicate the cardboard build with a ‘structural’ material [rather than the cardboard] would be to use the Home Depot/Lowes foam and layup fiberglass and epoxy fabric over it…

Unless you have access to a chopper gun, and weight and cost aren’t issues. It would probably be a lot faster to spray on the fiberglass. but without taking time to build a mold, the exterior would look all rough like chopped fiber and thus would have to be sanded a BUNCH to make it look smooth (if that were important to you).

With the fabric, you could make the sides laid up on a flat surface, which will make them smooth – you’d still have to sand the top, but not quite as much as if it were chopped fiber (IMO).

You should also prep the foam by removing any coatings, rough-up and clean the surface as well as putting some small holes 2 mm ( 5/64 in) diameter, 3 mm (7/64) deep and at a 50- 100 mm (2-4 inch) spacing before bonding. The small holes will help prevent the facesheet from pealing (a weak failure mode). It sounds like a lot, but don’t read too much into it. You can make a little roller with some appropriate nail sticking out that will pock the holes (I’d do that last) and the other is done with some course sandpaper. I would make a few small test pieces to load and break to verify you are getting a good bond and the strength you think you want/need.