Another thing to consider regarding pneumatics versus steels on the trails:
Steel wheels would be quite UNwelcome on many dirt trails, especially those intended for multiple use.
When we drove in one of our state parks (designed specifically for horses, hikers, and bicyclists), the park rangers were concerned about ruts created by carriage/cart wheels. They were won over in part due to my bay ambassador (kissing the rangers worked for Mingus), but also by the pneumatic tires on our CTM. Their concern was that the narrow steel wheels would be more likely to cut ruts into dirt trails. Gravel and paved trails aren't an isisue for either style wheel.
I would not even consider steel wheels on the beach.
We don't treat the trails like a CDE marathon course, so I don't foresee any runins with trees or other immovable objects. I did drive over a 6" high stump of a very small tree and hit a railroad tie while driving in my sister's woods -- no harm, no foul.
I should mention, however, that I would not drive anywhere without No Mor Tlats innertubes. I would also make certain the wheels have wider hubs for greater stability. Previously, that was the Achilles heel of the CTM carts, but now they have switched to the wider hub.
I love the looks of the G & S cart and the option of the steel wheels, but just because they call it a trail cart doesn't mean other EE carts (such as Frontier or CTM) are not appropriate.
As for springs, my back causes me constant pain, but honestly, coil springs don't bother me. Granted, I haven't used a Smart Cart, Bellcrown or anything with true suspension, so I have little to compare it to. I did do a schooling CDE in an old show cart with a slick wooden seat and NO springs...hehe...THAT was painful! For the second day I borrowed a HyperBike for marathon.
There is much to what Miss Susanne has said. We learned years ago to build the cart around and integral TO the wheel.
The wheel is the heart of the cart. Going through the "what if this happens" exercises is a big part of the design process.
Also and as an aside, properly constructed and MAINTAINED pneumatic wheels do not as a general rule blow-up or taco as is commonly held. They just don't, period. Before you counter this read all of the words in the previous sentences. I heard an ADS member at a meeting a couple of years ago state this as fact and it was all I could do to keep my yap shut. The issue is proper construction of the wheel for both the rig and terrain for driving and then, maintenance. The wheel previously shown was a welded hub wheel common to the industry. Had spokes loosened or stretched in this wheel prior to taco-ing? If so the wheel should have been replaced prior to damage. I know this wheel well and had used it for many years with only two taco's One event, I really don't know the details about but the second one I do. The owner ended up dropping the 110 lb rig on a tire edge from truck bed height. Yes this will cause even a competent wheel to taco. As to blow-outs, I personally know of none( for my own). This is because even within the wheel you need to choose components that are matched and work well together. As we focus on trail driving as our primary venue we build to that standard.
Now on with the other details,
Flotation on a specific substance, in general, is a matter of tire width and gross vehicle weight and it changes depending on the substrate one is driving on. There are other issues of lesser importance but in general it is width/weight/substrate. As we have been demonstrating for years now wider is better. We chose as our main tire a very wide tire with a flat surface on purpose as this will give us the best flotation on the most substrates including beach sand. Not just the tide mark sand, but the dry loose sand farther away from the water.
Depending on the substrate any rig will cut into the ground. The trick is to lessen this to the greatest degree possible. Cutting in means drag and greater effort for the horse. I would try to minimize this to the greatest degree possible.
Wider hubs are preferred as they generally provide better triangulation geometry that will prevent taco-ing. Ie. its a stronger wheel laterally. The few wheel failures we have had over the years are generally hub failures and especially with our composite wheel. These are lateral load failures. Lateral loading is a primary design aspect that should be considered in wheel design.
Looks like G&S is paying attention to the afore-mentioned design aspects.
As to "springs", we have taken two approaches over the years. Both are integral design features. One is an "add-on" that is purpose built. The other is to turn the entire rig into a spring. So you see, you were driving a rig with "springs".
Susanne, a 6 inch stump ain't nuthin. The RR tie had to be at least 8 inches if not more. Had there been a problem with these little objects, I would have been tempted to close my doors out of shame at my incompetence....
Just .02 from me and the crickets....
Bb
Graham Carriage Works
www.grahamcarriageworks.com
