The Torsion Axle Arrives

First a note about torsion axels.

 If you’ve ever pulled a trailer with a torsion axel, you know how awesome they are and you don’t need me to convince you.  I’ve never heard anyone say, I hate my torsion axel trailer.  I’ve had 5 trailers utilizing a torsion axel, and I love how they pull.  They’re smooooooth and never jump and hop like spring axels.

I had 3 criteria for the axel/frame:

  1. Soft, smooth ride:  Torsion 1,200 lbs rating
  2. Good ground clearance: 45 deg. down swing arm angle for about 15″ of clearance below the trailer.  Think gravel off-road overland touring.
  3. Narrow width:  For inline tracking behind a Jeep, while giving 4’6″ inside width.

After calling several companies and speaking with their engineering departments, I finally figured out how to order axels and measure axels.  Problem is, axel companies measure axels differently than how I measure axels, given my particular usage.  I had to first understand their language and then filter it through my usage needs to spit out a measurement that worked for me.

Here’s the data:

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This is a Dexter Torflex Axel from the Caldwell Idaho distribution center.  You need to special order these from an online axel company exactly how you want them, width, height and stiffness.  It takes about 2 weeks to get your custom axel.  But remember, this is the heart of your trailer.  Get the axel right and the trailer will fit your needs.  Fortunately, my axel arrived exactly as I wanted it.  Phew!

Now for the math:  I wanted 54″ width inside my finished teardrop.  With 51.5″ to the outside of the bracket, I’ll hang the trailer over the swing arms to gain another 1.5″ on each side, thus giving me a total outside trailer measurement of 54.5″.   By building the trailer to overhang the swing arms, it tucks the wheels up closer to the side of the trailer to minimize the overall width of the trailer.   After all, I want the trailer to have a narrow track and pull inline behind a Jeep or Subaru.

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This is the measurement no one could give me:  The minimum distance the swing arms hangs outside of the bracket.  The answer to this question is about 1.5″.  

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By building the trailer to overhang the swing arms, you get a total width of 54.5″ as measured outside the swing arm to outside the swing arm.

I’ll router a 1/4″ dado for the side wall to fit against the floor, leaving me exactly 54″ inside to inside.  Phew!  I’m glad that over and that it came out right.

Up next:  

I’ll have a welder, weld a long tongue directly to the center of the axel.  Onto this tongue, I’ll weld support arms with gussets.  The trailer will bolt directly to this tongue and support arms.  This step will take some time, so check in after a couple weeks.  

 

 

The Design Concept

 

Now that Scamp and Skiff America are built, I’m wondering what to build next. I thought long and hard about building another Scamp sailboat, which I would really like to do…at some point. But, my wife suggested I wait a year before diving back into another boat build. I think this is good advise. This allows time for John Welsford’s Long Steps design to more fully develop. It also allows Scamp to possibly evolve based on Howard’s experiences through the Straits of Magellan. I love the Scamp design, but think the boat could stand a few changes to make it even better. I’m happy watching others for a year and seeing how the design plays out.

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This is the napkin design, inspired mostly by my father.  I’ve often called him the best engineer I’ve ever met…still holds true.  It’ll be basic, as all good engineering should be.  It’ll work great for my requirements, which are of course quite basic.  I promise to keep it simple.  

So, let’s transition to Teardrop trailers. I’ve always wanted a teardrop trailer and watched their popularity grow over the past few years. Now there are dozens of good manufactures producing qualify teardrops. I’ve also watched the prices of these small practical trailers hit $10,000 – 15,000. This seems steep for what they provide: Which for me is essentially a hard walled backpacking tent. The industry has turned these simple trailers into complex units with showers, refrigerators, sinks, water pumps, holding tanks, colored mood lighting, the sky’s the limit…always in the name of being better. But, we all know simpler is better. My design criteria for a practical teardrop trailer would be a skosh better than a backpacking tent…more in line with a Scamp or Skiff America.

Namely:

  1. Trailer Dimensions comparable to a 2 person backpacking tent: 54″W x 80″L x 44″H
  2. Ventilation through both doors (no roof vent, they always end up broken).
  3. Roof rack for hauling bicycles and kayaks.
  4. Good ground clearance: 15″: think off road usage
  5. 14″ wheels: for smoothing out the gravel roads
  6. Cooking off the back: think basic single burner with one pot and one fry pan.
  7. Awning off either side or the back: canvas tarp 54″ x 80″ with 2 poles.
  8. Light weight: 700 -800 lb. all in fully loaded travel weight.
  9. Easily pulled behind any vehicle.
  10. Torsion axel for smooth independent ride: 1,200 lb. rating

That’s the overall design criteria. Now let’s build one

Most manufactures build either 4′ or 5′ teardrops. To me both widths seem wrong. The 4′ width is just too tight to sleep with anyone other than your wife for 30 minutes. The 5′ width seems too wide, especially if you plan to access mountain switch backs gravel roads. So, this forces you into ordering a custom axel exactly how you want it. This is actually a blessing. You get to build your trailer exactly how you want it…just like your boat.

Summary:

I’ve ordered a Dexter torsion axel that will be custom built to the above specifications. I can provide the technical details if anyone is interested. These are not overly expensive ($263) and provide the foundation to your teardrop. I’m not sure how this build will go…but I’m excited about trying to create a simple, practical, strong teardrop. It’ll come in very handy with all my outdoor adventures.