Video – Testing Twin Torsion Axles
Time to look at the action by Testing the Twin Torsion Axles. Video is a great way to see what’s really happening with the new suspension design! Especially when we can slow it down or freeze the video frames.
First, Some Background
At Mechanical Elements we are always fiddling with new ideas. This time, we decided to build a whole trailer around several new ideas like the Folding Tongue and a very long tongue and this new suspension. (More to come.) In the process, we have also posted about Building Trailer Frames and the Economics of a DIY Project — especially when adding new and creative bits.
With that background in mind, a deeper look at the suspension design (and the motivations for building it) are in this article about Tandem Torsions. You are now the beneficiary of the design, fabrication and testing that went into this trailer suspension prototype.
Let’s Watch The Video.
Portions of this testing are rather sevier as we don’t normally try to hit curbs with our trailers. Yet, as you watch, the frame bounce is not that harsh considering the size of the step up the curb. That is exactly the beauty of this suspension.
The second thing of note is how active the rocker beam is on the small bumps, and how the frame stays fairly still. Admittedly, some of the video effect is due to the camera mounting, but not all. The camera mounts, sort of, to the frame, but it is only with duct tape, so it does wiggle a little. If the frame was jarring, you would see that in the video.
Comparing to the first test with clamps holding the axles (in the early test video), this new video shows much more detail. The GoPro is a much better camera for this kind of work — not to mention the point of view. Certainly, looking at the suspension from under the trailer tells so much more.
Making the Suspension
To read more and see some about how we made the Twin Torsion Axles suspension, please see this post on Walking Beam Suspension for Smaller Trailers. Then, for your own build, blueprints for the rocker beam suspension are now available in the plans store.
Twin Torsion Axles Update
Since the time of this video, deck material was installed, and we’ve taken a few good trips. In the process we found with a trailer load, the twin torsion axles absorb more of the impact. The inertia of the load makes the suspension more active. Yeah, it stands to reason, but it’s worth noting anyway. Oh, and the rear wheel doesn’t hang up in the air on big bumps when there is a load.
As with most trailers, tire pressure makes a big difference in ride quality. Tires in the above video are full pressure (bouncy) to demonstrate damping effects of the rocker beam and rubber suspension. On a trip, we experimented with several pressures and found there is a sweet spot that takes away much of the trailer bounce and jostle. Higher pressure bounces more — as we expect, but very low pressure also gave more harshness.
The big takeaway from the test drives is the smoothness and how it handles large and small bumps. That is the goal of the suspension, so this is definitely pleasing. For a lot more info about this trailer and the test features, check out the background links above, and The Mechanic’s Post where everything is listed.
Thanks For Watching The Video With Us.