More New Product Announcements: The Mechanical Elements line of DIY Trailer Blueprints has just expanded – AGAIN – with more trailer plans for torsion axles. These new trailer plans fill in some of the blanks in the line of trailers by duplicating many of the sizes — but with designs made for torsion axles.
Since our goal is to serve you, we’ve expanded the offerings so there’s no question about using the plans with torsion axles. Prices for the new plans are identical to the matching trailer sizes made for Leaf Springs. These new plans are one more piece in the chain. And, as mentioned earlier, we are continuing to expand the line of plans. Please let us know if you have a particular size you’ve been dying to build.
What New Sizes?
Great question. The new plans this time around focus on our 3500# series. Single axle utility trailers.
The new trailer plans for torsion axles include the 4′ x 8′ – 3500# (shown in the image), along with the wider 5′ x 8′ – 3500#, and the very popular size 5′ x 10′ – 3500#. (Shown in the images at the top of the page.)
While these are a great addition, we know they are not enough. Stay in contact, because there are definitely more coming. That said, please be patient, because there is a lot of work that goes into the engineering of these plans. While it does take some time, it’s part of our commitment to make them the very best plans available to you.
Now with more options, it brings up the question: “Which Trailer Plans Should I Buy?”
If you’re considering it, torsion axles ride a little nicer, so even behind a car, they perform well. Because of that, these trailers are awesome instead of buying a truck.
Sizes We Don’t Have
We are often asked about tandem torsion axles. While we do see these in the wild sometimes (mostly for RV’s), tandem torsions are not a good idea. They don’t share the load equally, because they can’t. Here’s an article to explain it. Make sure you read the comments too, since some of our readers have had trouble just as explained in the article.
Edit February 2022. We have introduced a new concept at Mechanical Elements. Moving forward, we won’t be adding a bunch of new trailer plans for torsion axles, rather, we’re introducing Conversion Plans. That means you can get the trailer size you want, then get plans to convert the axle. Here is an article explaining the conversion plans.
Trailer Plans For Torsion Axles?
We have said a lot about selecting axles (read Trailer Axles 101, for example). And, we talk about design differences required for torsion axles as compared to leaf springs. Our new plans give you the small, but necessary design features to accommodate the loading and stress differences.
(Read some of the technical stuff in this article comparing Torsion Axles with Leaf Springs.)
Looking at the fun little Finite Element Analysis image here with all the pretty colors, it may look scary with all the reds. Yes, these are higher stresses when not compensated, but our new designs take that into account. The plans on offer at Mechanical Elements are Fully Engineered — not slapped together.
Most of our plans use leaf spring axles because they spread the load more, and for DIY’ers, they are less expensive (along with some other advantages). However, that does NOT mean we think less of torsion axles. No, they are just different, and they require some differences in mounting.
Torsion axles apply load to the frame in a little different way. Sure there is the vertical load carrying capacity, but there is also a torque component because of the arms that connect from the wheel spindle to the actual axle cross beam. As long as we enhance the design to handle that extra load component, it’s all good.
These new trailer plans for torsion axles do just that.
If you are in the market, please compare what other authors say about torsion force distribution in their designs. If they don’t discuss it, they probably don’t understand it. Here at Mechanical Elements, you don’t have to worry, because all our plans include the engineering.
In case you are not familiar with some of the technical inner workings of torsion axles, here’s a really quick overview. Please see the image. Basically, a square shaft within a larger square tube is constrained by rubber rods. The image here shows several section views of the inner shaft trying to turn and compressing the rubber in the process.
Within your torsion axle, as the torsion arm moves, the rubber compresses to allow suspension motion. It’s actually a pretty simple contraption once you get your head around what’s happening.
The rubber is convenient because it has a progressive force curve. That means when you push a little, it’s relatively soft. However, when you push hard, the amount it moves decreases with the increasing force. Some people describe it as being soft for small bumps, and hard for big bumps. (It’s over generalized, but it does convey the thought.)
What Axles Do We Recommend?
I’m not sure I’d call it a recommendation. There are a lot of good axles out there, so we’re not particularly biased. Our only caution is to choose one from a reputable company, and avoid the cheap (quality) ones.
Our trailer plans for torsion axles are based on the popular Dexter Torflex line. Of course, other brands will work, but some adjustments to the mounting holes may be required.
Anyway, we have chosen Dexter because: 1) they are widely available for you; 2) they are a good solid company; and 3) they have a lot of design information available if you want to read it. Since we have to choose something, that’s what we’ve done. Other than that, there is no special reason or connection.
See your local trailer supply to order your axle. Just use the last page in the plans drawing — it has all the info to order it. Since they are built per your order, they do take a couple weeks. In the meantime, get your Wheels and Tires ready.
Customizing The Trailer Plans For Torsion Axles
Again, we encourage customization, and with axles it’s no different. Just because the max capacity is 3500#, does not mean you must use a 3500# axle. For instance, to haul your luxury UTV, a 2500# axle might give a smoother ride. It’s perfectly fine to substitute a lower rating to fit your needs.
Also as a nice feature, these plans are not the super heavy duty trailers, so any vehicle with a Class III or higher hitch will work great.
Like all the trailer plans from Mechanical Elements these new ones also include options for customization. Choose what you like, and ignore the others. It’s pretty simple.
Get your trailer plans today, and get straight to building.