Teardrops n Tiny Travel Trailers

All,

I'm well on my way to constructing my tear I'll go and pick up the trailer I'm having made in two weeks. One of the last details I'm trying to work out is how I'm going to do the hatch. So far I've seen three predominate styles.

-The original style. A quarter inch is taken away from the galley sides to make room for a seal. Two inch aluminum angle goes over the hatch lid and rests against the sides of the camper. A seal goes underneath the angle. Flat strip molding is applied to the top edges of the galley sides.

-The fredrick style which is getting more popular. About six inches are dug out of the galley sides to make room for beefy side brackets on the sides of the galley lid. Inside the galley walls 1'/4" plywood is attached such that it goes an inch above the outer galley walls and rests inside slots in the galley lid.

-The third style seems to make a galley lid slightly smaller than the width of the trailer and use T molding with a seal on all sides. This seems to be the popular option for manufacturers these days.

So here is my question. The original design seems to me like it would provide the greatest longevity because water does not contact as much wood. from the outside going in there is an immediate sandwich of aluminum trim, angle, and a rubber seal. When the camper is at rest water cannot even contact the seam between the lid and the sides. The only weakness I see is that when the camper towed in the rain the angle could grab the water that runs back over the sides and push it toward the seal.

With the fredrick hatch design, water coming from the outside would get pulled between the two peices of trim (one on top and one on bottom) and come to rest against the 1/4 plywood (notch/seal). So water is always resting against wood in this design? I realize that we seal everything with epoxy but it still seems less than ideal. At the same time I can see the appeal of the added weight to the lid.

I haven't really given any thought to the third design other than to scratch my head and wonder if it's simply more aesthetic than the original design. It seems like water would more readily enter the seal both in motion and at rest.

Can someone comment on these design choices and refute any of my suppositions. I really would like to figure out what I'm going to do on my build.

Thanks!

Heres a Post I made earlier. There are many ways to do this but in the end....The one that doesn't Leak, is the Best.

I've always had a different approach to building a hatch. Instead of building heavy to prevent "Spring Back", Use materials that Don't "Spring Back"

I use FRP and Aluminum.

I build 2 outside rails, 1" thick (by using 2 pieces of 1/2") And cross spars. Then I cover the outside with FRP, good side in extending 1 1/2 past the rails on both sides.

FRP does not "Spring Back" and is strong enough when bowed around the hatch to not flex...as well as being stable enough to Triangulate the hatch.

I also install a second sheet of FRP on the inside, good side in as a finish.

2 sheets is more than enough, then sheath the outside with Aluminum.

I seal the outside edges with this;






I know, I know. But doesn't water get into the sides?

No! I build the sides in 3" at the hatch, and run the outside corner molding straight through. This is a very common area for leaks. The FRP/Aluminum extends 1 1/2" past the galley opening and I put a second outside insert molding on the inside of the galley.

This insert molding is 3/8" tall with a vinyl insert that acts as the hatch's seal. Plus I extend the offset Hurricane hinge past the galley opening.

For the water to get in it has to run down, make a right or left hand turn, run up hill and jump over a 3/8" tall molding that is under the FRP/Aluminum.

In addition the 2 outside corner insert moldings create a good Trough for the water to run down there by directing the water out and off the trailer.







Plus I extend the offset Hurricane hinge past the galley opening.


These shots are from 3 different trailers of mine, but the theory is still the same.

Happy Trails

Len

Len,

I like your design but I'm afraid when you say, 'I do it all with FRP and aluminum" it's a bit like Michelangelo saying, 'I did it with brushes.'

I've never worked with FRP nor aluminum. I have worked with wood which is why some methods are easier for me to grasp than others. Tell you what, make a dvd and I'll buy it! If we were neighbors I'd bring you beer and sit in your garage. You do good work!

With the Fredrick's hatch, the lip that sticks up from the galley into the hatch is actually 1/2", not the 1/4" that you mention. (And there's a 1/8" shim that sits between it and the wall. The slot in the lid is 3/4" wide that the seal sits in.)


On my galley/hatch, all of the exposed wood has two coats of epoxy followed by two coats of UV varnish. You are right, those places are exposed to water, but the wood isn't since it is enveloped in epoxy. Also, by the nature of the beast, any moisture that gets on those surfaces quickly runs down and off and doesn't have time to puddle. I don't have a moisture problem.

My first teardrop was a commercially (CNC) built teardrop, a Hunter, that leaked through the sides of the traditionally built hatch and damaged the wall. I put a lot of time attempting to solve the problem before I sold it –but I told the new buyer that it needed to be stored indoors or tarped during the winter. That hatch will never be as dust and water proof as my Fredrick's style hatch.

But there are many ways to skin a cat and most of them work quite well.

T

First let me say that I have MUCH less experience here than most. BUT I have done a lot of research, and used/am using the frederick method on my hatch. Here is what made me go that route.

1. I used the stick framing method, and his method uses that for the rest of the sides, so this was just a natural move to cut those back pieces out and do that.

2. I had read about spring back, and his method seemed to cut that out completely. I like extra beefed up side/ends that form the seals.

3. I like the cross framing method that his uses rather than cutting ribs for the hatch. lthough there was a bit of learning curve on the front end, cutting out the pieces that would form the end of the hatch, the assembly in the end was really easy. Clamp everything back together, add gussests, and them fill in with cross members (1x3 poplar for me). It turned out to be much easier than I thought it would be.

4. The hatch seal area just seemed to really make sense to me. Just accepting that water is going to get in and then making it run where you want it too.

5. I am using aluminum on mine. Given that his design is made for a woody, this caused a bit of an issue when thinking about the eventual trimming of the hatch. Luckily I came upon Tony.latham and his build. He gave me lots of help on that aspect of things, and looking back it is REALLY easy to adapt the Frederick method to use aluminum on those end pieces of the hatch.

Don't be scared off my the metal/wood thing. Aluminum is REALLY easy to work with, and I'm glad that we went that route along with the Frederick hatch. I know the other methods are tried and true too.. I don't knock any of them, but these are the reasons I chose to go that route. I bought the shop manual too.. and everything just seemed to make sense and fit together.

Annnndd. I see that tony posted a reply just before I finished typing. Good stuff!

Well, experience trumps all. I guess I'll go with the fredrick hatch.

Where can I get a copy of the plans for this hatch style

dales133 wrote:Where can I get a copy of the plans for this hatch style

http://www.campingclassics.com/shopman05.html

T

Cheers tony

Dalorin wrote:Len,

I like your design but I'm afraid when you say, 'I do it all with FRP and aluminum" it's a bit like Michelangelo saying, 'I did it with brushes.'

I've never worked with FRP nor aluminum. I have worked with wood which is why some methods are easier for me to grasp than others. Tell you what, make a dvd and I'll buy it! If we were neighbors I'd bring you beer and sit in your garage. You do good work!

FRP, Fiberglass reinforced Panels are very easy to work with. I use them because they do not "spring Back".

I use it to replace the 1/4" plywood that most people use as sheathing....the stuff that causes "Spring Back.

It is a sheet good that is locally available anywhere for about $30 a sheet. 1 sheet will do a hatch, inside and out.

If you can do it with wood, you can do it with FRP as Sheathing.

Then I cover the outside of the FRP with Aluminum and do the edges with the Cap molding.

easy Peasey.

THERE IS NO PORTION OF THE FRP THAT IS EXPOSED TO THE ELEMENTS.

If you need to see a sample of FRP, go into any McDonald's Bathroom.

FRP will last as an outside material.

Same Kid, same Trailer + 20 years




viewtopic.php?f=2&t=35105

Happy Trails

Len

Gunguy05 wrote:4. The hatch seal area just seemed to really make sense to me. Just accepting that water is going to get in and then making it run where you want it too.

I'm in complete agreement with that.

Argo the Molding trench.



Happy Trails

Len