I was curious, looking at the differing shapes of the RV's -- some "Boleresque" with softer lines and rounded corners and others, like the Beachcomber and Trillium Jubilee, with a squared-off shape.
Other than esthetiques, are there any functional differences between those two predominant styles? I've heard the squarer design has a feeling of greater interior space, but I am also wondering about "nuts & bolts" differences. For example, (from my research on this awesome site) a common problem is door sag -- is there any benefit to the door style in say a Trillium Jubilee vs. a regular 1300/4500/5500 Trill? What about replacing windows ... modifications ...?
Anyone with practical experience that would care to comment? Thanks.
You no doubt have heard of the carney trick involving the difficulty of breaking an egg by pushing on the ends with thumb and forefinger. The ends are very strong-basically arches rotated thru 360 degrees. Our camper eggs do not quite copy the geometry of the chick packaging ovoid but they do share surfaces of compound curvature, the corner radii in cases where these curve in plan or elevation and in the more egg like [Boler], large wall and end facets are also compound curves which resist deflection.
The Trillium/Amerigo/Bigfoot style uses corners of lesser radius and frequently no curvature in plan or elevation views. The sides and ends approximate true planes rather then compounds. I believe they are less resistant to deflection than is the more egg-like Boler/Scamp/Casita/Burro style.
It is clear to me that the designers who tended to the egg shape rather than radiused rectilinearity understood very well the benefits of curves as sectional stiffeners. These are usually the trailers that also employ the trolley roof section--an iteration of the wall to top and wall to end radius. Most of the trailers that tend to the rectilinear "trough" styling do not use the trolley top. Bigfoot is a case where internal framing (transverse battens or carlins) was employed to stiffen rooves against deflection.
I prefer the self-stiffening of the more egglike eggs. However, a door that will seal and seal reliably requires a rigid door case. A door case, curved or planar, protrudes inward or outward or both. Frequently, an adjacent interior partition or bulkhead acts as a stiffener at one side of door but is not all the engineering required. I believe a time and wrack-proof door opening is problematical in both classes of design. The flat door is much easier and cheaper to build and repair but many will say the eggsthetics suffer as a result.
Wow. Excellent, extremely thorough analysis. I had no idea the "protective" egg properties translated to that scale -- I honestly thought the design idea was moreso related to wind resistance and esthetics. Thanks. Another layer to consider.
You no doubt have heard of the carney trick involving the difficulty of breaking an egg by pushing on the ends with thumb and forefinger. The ends are very strong-basically arches rotated thru 360 degrees. Our camper eggs do not quite copy the geometry of the chick packaging ovoid but they do share surfaces of compound curvature, the corner radii in cases where these curve in plan or elevation and in the more egg like [Boler], large wall and end facets are also compound curves which resist deflection.
The Trillium/Amerigo/Bigfoot style uses corners of lesser radius and frequently no curvature in plan or elevation views. The sides and ends approximate true planes rather then compounds. I believe they are less resistant to deflection than is the more egg-like Boler/Scamp/Casita/Burro style.
It is clear to me that the designers who tended to the egg shape rather than radiused rectilinearity understood very well the benefits of curves as sectional stiffeners. These are usually the trailers that also employ the trolley roof section--an iteration of the wall to top and wall to end radius. Most of the trailers that tend to the rectilinear "trough" styling do not use the trolley top. Bigfoot is a case where internal framing (transverse battens or carlins) was employed to stiffen rooves against deflection.
I prefer the self-stiffening of the more egglike eggs. However, a door that will seal and seal reliably requires a rigid door case. A door case, curved or planar, protrudes inward or outward or both. Frequently, an adjacent interior partition or bulkhead acts as a stiffener at one side of door but is not all the engineering required. I believe a time and wrack-proof door opening is problematical in both classes of design. The flat door is much easier and cheaper to build and repair but many will say the eggsthetics suffer as a result.
Regardless of the shape of the rest of the trailer, almost all window areas are designed to be flat, so special windows are not required, and the shape does not affect the installation. Similarly, large flat areas on the sides accommodate refrigerator vents and other fittings.
Notable exceptions are the front windows and in some cases rear windows of the Boler 1300 and various trailers (such as Scamps) derived from it. These windows are just flat sheets of acrylic held in the opening by a rubber gasket; they are not formed to curve of the body, they are just forced into place and will spring back to flat if removed (at least initially).
__________________
1979 Boler B1700RGH, pulled by 2004 Toyota Sienna LE 2WD Information is good. Lack of information is not so good, but misinformation is much worse. Check facts, and apply common sense liberally.
STATUS: No longer active in forum.
The functional differences between build molds is where the seam is.
Some have an upper & lower half shell and others the seam is from the middle. Given the risk of acceptance and cost of molds there is not much incentive for a manufacture to stray from the norm.
I do believe that a Scamp or Casita would provide better gas milage with the rounder shape.
I think the Bigfoot with all the additional framing provides a stronger structure same for Trillium .
The Trillium/Amerigo/Bigfoot style uses corners of lesser radius and frequently no curvature in plan or elevation views. The sides and ends approximate true planes rather then compounds. I believe they are less resistant to deflection than is the more egg-like Boler/Scamp/Casita/Burro style.
It is clear to me that the designers who tended to the egg shape rather than radiused rectilinearity understood very well the benefits of curves as sectional stiffeners. These are usually the trailers that also employ the trolley roof section--an iteration of the wall to top and wall to end radius. Most of the trailers that tend to the rectilinear "trough" styling do not use the trolley top. Bigfoot is a case where internal framing (transverse battens or carlins) was employed to stiffen rooves against deflection.
Raz, the first foto; is that Lum's Pond in DE? Looking at your Trill, I'd say it has a raised central roof area. Is that the case? Scamp does not have a such a roof but Casita, Burro, UHaul do. Not certain about EggCamper.
It may be that not every urban trolley car had a roof with a raised central section but many did, hence the derivation trolley roof or trolley car roof. On most of these trailers, the demand for full standing height in the central corridor and only there may have been a consideration as equally important as roof stiffening in the genesis if this feature. Oddly, the ParkLiner has what is referred to as a "reverse trolley" or pontoon roof showing a raised longitudinal area at each side of trailer. This feature is admired by those for whom overhead storage is paramount.
Parkliner has an anti trolley roof without windows, flat on top. If you are old enough to remember riding in streetcars and some railroad cars, the roof was elevated but flattened and had windows for ventilation which due to them being under the roof kept some rain out. This also made the roof stronger than it would have been without. See here Light Rail Products: Railroad Roof Modification
__________________ Jim Never in doubt, often wrong
Jack,
Unless I've mis-read your post, Scamp does have a trolley roof. Beyond providing central aisle headroom, it stiffens the roof, much like rippled truck beds.
Raz, the first foto; is that Lum's Pond in DE? Looking at your Trill, I'd say it has a raised central roof area. Is that the case? Scamp does not have a such a roof but Casita, Burro, UHaul do. Not certain about EggCamper.
It may be that not every urban trolley car had a roof with a raised central section but many did, hence the derivation trolley roof or trolley car roof. On most of these trailers, the demand for full standing height in the central corridor and only there may have been a consideration as equally important as roof stiffening in the genesis if this feature. Oddly, the ParkLiner has what is referred to as a "reverse trolley" or pontoon roof showing a raised longitudinal area at each side of trailer. This feature is admired by those for whom overhead storage is paramount.
jack
Lums? Yup
Perhaps not a good picture but if you look closer at the Scamp roof.
Trailer: 1972 Boler American and 1979 Trillium 4500
Posts: 5,137
Quote:
Originally Posted by rabbit
You no doubt have heard of the carney trick involving the difficulty of breaking an egg by pushing on the ends with thumb and forefinger.
I feel this applies in general theory when comparing our eggs to stick builts. Then we have to factor in that a hole of approximately 20% is cut into the circumferential structure for a door. In some models more for a floor. Where those two points meet is a week area oft cited as being a major factor in door sag.
The structural integrety is improved with the addition of various countours in the surface. For example the "trolley roof" not only allows for increased height, it increases structural integrity and prevents the roof from flapping as we drive down the road.
Other factors to consider are how the various components are joined. Are they riveted together? Are they screwed to wood or wood products laminated to the fiberglass? Are they glassed together at structural features?
One has to look deeper than the outer skin to understand the differences.
Thanks for the correction, Norm. The raised section is very hard to detect, at least by me. Is it the case that the Scamp roof displays more of a ripple or corrugation, as in your truck bed analogy, rather than a deep step?
Brian, there is a recent thread by Cathy Futrell, subject being her difficulty getting rigid window frames to fay with the vertical wall curvature of her Love Bug. One correspondent concluded that the wall curvature in the window area was likely the result of outward sag due to roof weight rather than mold-determined.
From the front or rear it's difficult to detect the Scamp's trolly because it blends down to the curvature of the trailer. From the side it's clear that it's 3 or four inches. The top of the trolly section is also curved like most Scamp surfaces though not too much for a flexible solar panel.
Hmmmmm, it sounds like we are discussing the design of the next spacecraft to Mars..... where a single fitting can cost more than a new Scamp.
It appears that the sagging door issue is more associated with certain mfgs. than shape. Bigfoot, for example, built a 13' egg, but used a square edge flat door to take care of that issue.
And remember that Boler begat Scamp and the dozens of other followers just knocked off from those designs, hence the popularity of the shape.
I think that personal preference and use trumps any MPG differences that shape might imbue.
For a given envelope size the square trailer will have more useful storage and sleeping space. Those that get relegated to the back area of the dinette/bed (me)or the front bunks of most Eggs will agreed I am sure.
As far as sturdiness, my 1973 Hunter is as old as 99% of the eggs out there and it's square shape is as sturdy and rigid as it was 40 years ago.
Again, go with what you like, and ferget the engineering considerations.....