Teardrop 1 trailer

Welcome to the Teardrop Trailer #1 journal for a design & build project I’m working on!
Comments are welcome!
Older entries (version 1.001, etc.) are at the bottom, & latest entries are at the top.
Estimated completion: May 2019.  Sale soon thereafter.


Teardrop 1.21 4’0.5″ x 10’5.25″ – I’ve put the trailer frame together.  Because of the bolt hole configuration, the trailer is now 10′-5.25″ long and 4′-0.5″ wide.  It could have been about 5 inches longer, but stress tests proved it would reduce the carrying capacity too much.  Plans on Revit have been altered accordingly.  Next step: purchase materials and build the floor.


Teardrop 1.18 4×10 – I wanted to see how things would fit if I went with a 4×10 trailer instead of a 5×10.  It all fits.  I had to go with a smaller microwave.  This saved me two inches that I could use to include the sink I have.  Hmm.  Spend $80 on a new (smaller) microwave or $150 on a new (smaller) sink.  I went with smaller money – that is, smaller microwave and larger sink.

The trailer weights are similar.  Comparison:

All can be expanded to 10 feet by not using the hinge feature.  Not sure who will win out.  I did purchase the 5×8 last night from Inflatable’s website, but they won’t get shipment in from their suppliers until the end of Nov. 2018, so I had to cancel the order.  (Place Sad Face Here.)

Furthermore, I think the additional cost in materials – plywood, mainly – will necessitate going with a 4×8.

Plus, the Excel spreadsheet I have to calculate costs, weights, moments (weight distribution across the tires), and such is now geared for a 4×8 (that is, 4×10) trailer.

Here’s the latest.

I tried rotating the stove (cooker, stove top, hob, whatever you want to call it) to sit horizontal to the counter top.  I thought that it would offer better cooking ability to have the burners side-by-side.  But a) it doesn’t give enough clearance for the microwave shelf wall, and b) I think it takes up too much counter space.

I turned it back.


I created an antenna mount yesterday and put an antenna on it today.  Pretty time consuming making Families for Revit.  But I think it looks good.  I also put this on my blog.  See radio transceiver antenna mount.


Teardrop 1.17 corrected walls, doors, roof – Things change.  In this version, the walls are corrected.  The arc was wrong on a couple of walls.  Just cleaning up the drawing and correcting mistakes that I knew were there.  The roof is on.  Now I’m playing with the best way to represent wall and roof 1×4 and 1x6s in Revit.  Expensive framing add-on to Revit?  Manually sticking lumber wherever I need it?  Is there something in the Structural menu that I can use?  Still fiddling, still learning.  Once these are accomplished in a satisfactory way, I can begin working on the actual drawings, with dimensions and such.  From there, a bill of materials.


Teardrop 1.16 insulated floor – In this version, the floor is as others have suggested – an insulated floor.  Previously I put the insulation panels between the trailer’s frame members.  But:

  • The steel cross members of the trailer are themselves not insulated and, being steel, will allow a lot of leakage of heat.  Even if they were wood, they would still not insulate well.
  • Adding insulation blocks under the trailer would not be fun.  I really don’t want to crawl around under another camper ever again.
  • Sandwiching (screwing & gluing) layers of plywood (top & bottom), lumber (1x2s & 1x4s), and rigid insulation panels would create a much stronger floor.  In the corners, where the floor meets the trailer structure, there are bolts holding the trailer together.  Drilling out bits of plywood to allow for flush contact will add serious weak points to a single sheet of plywood.

So this version has 3/8″ ply, 1×2 (which is 3/4″ thick), and another 3/8″ ply, totaling 1½”.  This would raise the countertop by an extra inch, totaling 32”, a bit too high for my taste (30” max).  The solution?  Keep the counter at 30” and put in a smaller grey water holding tank (10ℓ).


Teardrop 1.15 roof mass structure – In this design I tried to create, in Revit talk, a mass.  It’s a volume of space (3-dimensional) that is not meant to be seen in any drawings but gives the designer a shape to work something else around, like a roof.  I failed because of either a shortcoming in Revit or me, one that disallows masses to be extruded sideways (i.e. from one wall to the other).

As it happens, I didn’t really need this.  I could have just put a roof on an already existent structure – the walls – and offset the roof line by 1/4″ inch (so, in essence, drawing the ceiling line to make the roof).  Why 1/4″?  It’s the inner skin of the roof sandwich.

The inner 1/4″ ceiling plywood will be lain perpendicular to the walls, on the 1/4″ inner wall and 1×2 wall structure.  This will give it enough roof surface area to firmly attach to the walls.  1×2 spars will follow atop the 1/4″ inner ceiling plywood and give the force necessary to keep the ceiling plywood curved around the walls, starting at the front wall, around the front curve, and over top the actual roof, to terminate at the galley – all colour-coded here for your convenience.  Rigid polystyrene insulation will fill up the gaps between spars.  (Spars not included in this drawing.)

I know what you’re going to say.  “There seems to be a gap between the ceiling and the floor, in the second picture.”  Yes. I have to fix my walls.


Teardrop 1.14 – changed roof line again.  Some bloggers say that a 4×8 piece of plywood can be bent to a 20-inch radius, and this is supposed to be a “teardrop” shape, so I’m going back to the curved front & rear ends.

In the process, the roof curve itself has been slightly straightened to allow a little extra height at both ends.

I created some door families.  Wait – what?

At various points in this project, I created a few “families”.  “You did what?”  Rather than me explaining it, I’ll let Autodesk.  I created:

  • Allpowers 100W solar panel
  • some 6×9 speakers (parametric for various plywood thicknesses)
  • a horizontal GFI outlet
  • a door
  • some beaded pine plywood
  • a mattress
  • a sink (parametric) to match the one from the Sprite trailer or whatever sink might fit
  • 4-inch water tanks also from the Sprite  (Yes, they are actually 4″ tall.)
  • a mousepad (to cushion the water pump)
  • an Amarine Made AMBP1-G750-07 bilge pump
  • fuse box R3-76 (in various rotations, with various mounting types)
  • the NRE logo (twice)
  • a SHURflo 4028-100-E54 water pump
  • a few inverters (some nicer than others)
  • Aqua Pak 10-litre water container
  • Aqua Pak 20-litre water container (I couldn’t figure out how to parametric the 10-litre)
  • Dometic SeaLand portable toilet (just the box shape, not details)
  • a turntable to rotate the stereo
  • a Reliance Desert Patrol Water Container, 23-L
  • a Noria Window Air Conditioner
  • a few microwaves (no details)
  • a Marey GA5LP Gas Water Heater
  • a Coleman Powerchill™ 40 Quart Thermoelectric Cooler

All of these are a little crude, but they suffice to add to the project.  You’ll eventually see them included in the trailer.  I want to make sure I’m not stepping on anyone’s toes legally speaking before putting pictures of them online.


Teardrop 1.13 – I went with a 4×10 trailer here to save money on materials.  5×10 would have demand more non-standard size material.  I put a car in front of it to see how things would feel.  I couldn’t find a 2012 Kia Soul in a BIM file anywhere, so I went with the Kia Sportage.  They’re roughly the same width and height, give or take.

This whole project is meat to come up with a build to easily be towed behind a little car.  I have a 2.0ℓ engine in my Soul.


Teardrop 1.12 – lowered roof.  I’m not sure why I decided to lower the roof.  Just playing around, I guess.  No, that’s not it.  I’m going for aerodynamics, not full-size, full-featured.  It’s a stretch wanting to put a water heater in it, but I have it, so there you go.

Of course, with the lowered roof line, everything has to move.  A balance – lower the roof line, less fits.  Raise the roof line, everything fits, but it looks like a big piece of plywood rolling down the road.



Teardrop 1.11 – a simplified roof line.

I thought of bending Plexiglas to create curved windows for the front and back tight-radius areas, buying bendable Luan panels from Windsor Plywood, and skinning the front with a metal rock guard.  In the end, I went with a simplified roof line – 2′ straight up, then a 7′-6″ radius for the roof.  (I can bend any piece of three-eights-inch plywood to that curve.)

At some point, I put speakers facing into the berth, a cabinet at the front of the berth, a mattress (53″ x 74½”, RV full size), and the NRE symbol at the rear.  The sink & stove are also facing lengthwise front-to-back again giving more counter space.  The stereo, CB, & solar controller continually move.  I had them anchored to various things before, but there’s no point in nailing anything down yet.


Teardrop 1.10 is a version 7 converted to a 10′ without all the other changes.  Thank goodness for Save As…

I also thought I’d have these doors open upward, so-called gull-wing doors.  It would:

  • shelter from the rain,
  • keep drops from falling into the cab, and
  • offer a roof for a shower area – just hang the curtain around the door (which is why the door is so wide).

Good, except that I’m taller than that.  I’d have to stoop way before I got close to the door hole.  Plus, it would add complexity to the door (piston to hold the door open).


Teardrop 1.9  The answer, of course, is to make it bigger!  According to many, such as the author(s) of How To Build A Teardrop Trailer available on Wikibooks, it is easy to convert an 8-foot trailer into a 10-foot trailer.  Since this is not going to be a folding trailer as envisioned by the manufacturers of the trailer frame, the two side-by-side cross members for hinging together the trailer can instead be turned 90° and used to elongate and brace the outer frame members.  Still confused?  Have a look at the picture.

So now I have a 10′ trailer in the plans, giving me two 2′ sections to put stuff – one for the galley (fridge, stove, sink, microwave, etc.) and one for storage (water tanks, propane water heater [which now does not have to be any particular height], the portable toilet that everyone loves to put next to their food, and a bit of storage accessed inside the berth).


Teardrop w1.8 is geared to be a little more streamline.  It sits at 4′-7½” total height from the ground and includes a 12-inch radius curved cut front, roof, & rear.  No, the innards aren’t going to stick up like this.  But I want to get the shape right first.  That’s one of the few artistic expressions of teardrops – the shape.

This compromises available space in the galley.  Where will the water tanks go?  And the microwave?  They can fit down below.

The microwave will be at a less convenient level, but,

  • It won’t force the user to reach across 18 inches of counter top plus the depth of the microwave to get at food.
  • You won’t burn your arms reaching over top propane burners.
  • Kids can microwave popcorn.
  • I can microwave my coffee without raising my butt out of my chair.  How convenient.
  • Plus, there is a space for a drawer for pots & pans (well, perhaps only pans) under the microwave.  It also lowers the overall center of gravity by a smidge.

Benefits abound.

But it’s so dang wide!  The microwave is 19″ wife, and the fridge is 24″.  That doesn’t leave much.  What to do, what to do.


Teardrop 1.7 – nothing really new to report here.  I tried a few things, moving various parts around.

Where do I put the water tanks?  In this version, there is a fresh water tank on the right (passenger) side and grey water under the sink on the left.  To have the water tanks fit, the counter top needs to be raised to more than 3′-2″ from ground level.  How high is your stove & sink at home?  I bet it’s not that high.  People usually bring their kids camping.  Do they have to stand on something?  Unsafe.  I did the scientific tape-on-the-door method to get a proper feel for the heights of various components.

Does the grey tank have to be the same size as the fresh?  I should think not.  The 20ℓ Aqua Pak tank from Canadian Tire is good for fresh, but I doubt very much the grey water needs to be more than 10ℓ.

Again, I didn’t get carried away with wall studs yet because I’m not entirely satisfied with the overall shape yet.  No wall studs done.


Teardrop 1.6 is changed to a 5-foot wide trailer.  As one online comment states, what is the point of building a trailer if you’re not comfortable in it?  Go for the extra width.

The sink & stove are placed wider the way you’d expect them to be.

I began to place 1×2, 1×4, & 1×6 boards to see what the framing would look like.  But something just doesn’t feel right.  It’s 5 feet wide, 8 feet long, and 5 feet tall.  Rather boxy.  Not a fan.


Teardrop 1.5 separates things that should be separate.  The fridge in the middle means it cannot vent to the side, but it also means there can now be two supports for the counter top on either side of the fridge.  The stove & sink are both inserted with their lengths placed front-to-back.  What can you do with a 4-foot wide trailer.


Teardrop 1.4 – can you see a difference?  Well, the sink & stove next to each other really doesn’t make any sense.  Can I separate them?


Teardrop 1.3 shows a rearrangement of stuff in the galley and a sink. The microwave oven now sits on a shelf.  With it up there, I can put in some cabinets.  But do they face the galley or the berth?


Teardrop 1.2 shows the water heater actually fitting.  How?  The insulation is put between the trailer frame members, reducing the height of the floor by an inch, allowing for a whopping extra inch leg clearance.  Nothing else is arranged yet.  It works, but this doesn’t offer a lot of space for one’s feet in the berth while sleeping.


Teardrop 1.1 basic idea  Here we go!  This is the original concept.  After downloading a trailer frame from RevitCity, I began building the concept in Revit.  Verstion 1 is on a 4×8 Harbor Freight folding trailer, what many people typically base their teardrops on.

The profile is bulbous at the front end and streamlined at the rear, although not by very much.  It uses a 4×8 sheet of plywood as its side wall.  The 1-7/8″ inset at the front and rear gave an extra 3-3/4″ curved overhang at the front.

The floor is a sandwich of 3/8″ ply, 3/4″ polystyrene insulation, & 3/8″ ply.  The bottom is coated with a roofing tar (don’t know what type yet) and top with polyurethane.  It covers the entire frame.

The side walls, 1/8″ interior skin, 3/4″ insulation on 1×2, 2×2, & 2×4 framework, & aluminum skin, are bolted to the side of the floor.  Hanging walls?  Commonplace in teardrop construction, I know, but this is not idea in my view as there is no solid platform for the walls to sit on.  Still, it offers a full 4′ x 6′ berth area.

Here is a transparent view to show the water heater, speakers, CB radio, stereo, microwave, sink, fridge, and door.

The main issue with this is that it’s so dang tall.  The reason I’m dismantling the 1965 Sprite trailer is that it offers way too much wind resistance for my little Kia Soul.  This is better but not great.  Other issue:

  • water heater – not enough clearance, but no where else to put it
  • microwave oven – opens onto the counter top (must counter clear at all times)

Back to the drawing board.