A DIY Teardrop Travel Trailer

Thursday, March 7, 2013

Supplies, Parts, and Links

This list will grow as I go through  my build, but I thought it might be handy to publish links to items that I purchased and some of the tools that I used.  Do not assume that this is a full list, as I already have many of the tools necessary to work on this build.  These are just items that I purchased specifically for the teardrop build.  I apologize if I miss anything.  If you see things in my build journal that is not included here, let me know and I'll add it.


Steam Bending
Electrical & Radio
Tools

Monday, March 4, 2013

DIY Steambox for Bending Wood

** CAUTION **

Using a steam box to bend wood is potentially dangerous.  Adding steam to any type of enclosed space creates potential for dangerous situations due to the high pressure and "steaming" hot vapors and liquid.  Ensure that you have a place for steam to escape.  The following information is provided knowing that you are intelligent enough to make your own safety decisions.  Building a teardrop trailer does not require steam bending wood.  I am going for a unique look, and have decided to attempt this method.  Please do not try this at home without taking safety precautions.

Building a DIY Steambox

My grand teardrop design is a woodie, which means that the exterior has the wood showing, versus what many people do by skinning it with aluminum.  My design calls for bending wood to match the shape of the teardrop.  In order for me to accomplish that, I need to construct a Steambox.  I have multiple lengths of wood that need to be used, so my steambox will be modular.  I'll build the 1st section at around 6 feet long to accommodate the shorter wood that needs to be cut.    Here are the supplies you'll need:

4 -  6'x6"x1/2" boards
1 - 1/2 Sheet of Pink insulation
1 - Steamer (Earlex Steam Generator)
9' - 1/4" Wooden Dowels
1 - Thermometer
50+ - 1 1/4" Exterior Grade Screws

Once the box is ready for steam, you'll also need these items
1 - Thick Leather Work Gloves
1 - Safety Glasses
6+ -  Clamps

Design:


I'm not sure how much the insulation will help, and I didn't do a very good job of cutting it straight, so there are some gaps.  It's my understanding that you probably don't want a super air-tight steam box, and you do want some vapor to escape, or you're likely to end up with an exploding box.

The Earlex steam generator came with a brass fitting the I've attached to the box almost in the middle.  

I used wooded dowels spaced about 7" apart.  These will help keep the wood raised so that the steam can reach all sides better.  

A look inside the box with the dowels attached.



I purchased a cheap kitchen thermometer so that I would know how hot the inside of the box gets.  I used aluminum tape to seal all the edges. 

Here is my test piece of Red Oak inside the box.  You can see the probe of the thermometer to the right.

Testing DIY Steambox

Here is the steamer connected and a towel stuffed in the end to close off the box.

General rule of humb is 1 hour for every inch of thickness of wook that you're steaming.  Mine wasn't that thick, but I also didn't soak it ahead of time. I didn't realize that I would finish the box so quickly, and decided that I couldn't wait to try my hand at bending wood.  On my next test, I plan on soaking the wood overnight, and then try a shorter steam time, since my wood was just under 1/4" thick.

Here is a timelapse of the temperature gauge.  Not all that interesting, but I wanted to see how quickly the box heated up, and what that average temperature was.  It hovered just around 215 degrees for most of the time.

I created a template to bend the wood around using parts that were cut on the CNC machine out of 3/4" signboard.  Glued together, this will become where I clamp the wood after it comes out of the steamer.  

Example of Tongue box lid bending form


I did record my first bending attempt, and here are a few screen shots of me attaching the steamed red oak to the template.


I'll probably keep this in the clamps for almost a week before removing.  In the meantime, I have a few more templates to build.  Successful first attempt at steam bending!  I may try using a metal strap on the outside of the wood as well, as research shows that it compresses the inside wall of the wood more than expanding the outside edge, thus leading to less breakage.  

I'll post pictures when I take the test piece out of the mold template.

Edit:  04.25.13 Poplar Test Piece
I steamed a test piece of Poplar last night.  I soaked the wood for about 30 minutes before I had the steamer all warmed up.  Not sure if that helped or not.  The wood was in the steam box for about 40 minutes, where the internal temperature got up to about 210 degrees.  The wood was very bendy and flexed about the 90 degree bend without much effort.  I've finally ordered my planer, so I should be able to test a few more wood options this weekend.


CNC: The Art of Cutting a Template

I made the choice early in my design that I would use a CNC machine to help cut parts for my teardrop build.  The thought was that this would speed up the process considerably in the beginning.

Time Lapse of CNC Cutting Teardrop Parts



* Drawings are used courtesy of DaveMcCamant, and the copyright and ownership remain with him.

Here is an example of the interior template drawing.  The holes in the work surface will be filled with insulation.


Using the method of removing excess wood will help keep the weight of the trailer down.  I'm worried that since I'll be using more wood  than most people, my trailer will be on the heavy side, so I'll remove as much unnecessary wood as I can.  The template design you see below shows in pink where insulation will be added, which is a lightweight material compared to the signboard.


Here is an example of how the CNC can cut parts for the tongue box.  Some of these pieces will be used as a template for bending steamed wood.


Lid of Tongue Box was cut with CNC Machine

Hatch template parts, with internal cabinet framework.


Custom Trailer: Update 5/13


I was lucky enough to come across another teardrop builder on the TNTTT.com forum who was willing to share his design drawings.  The copyright and ownsershipof these drawings remain with Dave McCamant.  The main differences in my trailer from the original, is mine is 2" wider.  I have also added a 2" receiver to the back of the trailer, along with a couple of 1.25" side receivers for tables or awning poles.



Trailer was ordered in mid-February of 2013, and was ready for pick up on 5/13.  Over a month overdue, but it's in my garage ready to go.




Flexiride Torsion Axle with brakes

58" across, just like the plans asked for.

Angle mounted trailer stabilizers on the back corners

Receiver on the back, for bike rack.

Deck mounting tabs




I plan on adding a PetCool air conditioner/heater to my teardrop.  I have chosen to create a design that will incorporate a raised deck with all electrical and air return within this raised deck.

Sketchup Drawing of the partial deck with raised sections, and additional lowered storage compartment.


Why build a teardrop travel trailer?

After taking a long journey out to Glacier National Park last summer in our Toyota Highlander SUV, I came to the conclusion that I needed some type of RV. (Check out Trip Pics Here!)  I'm more of a traditional tent camper, but can immediately see the benefits of having a rolling enclosure that has everything you need.  The compromise, was a teardrop travel trailer.  Through the wonders of Google, I discovered the TNTTT.com website which is a community of teardrop builders.  Caution, browsing this forum can suck countless hours out of your life.

I knew that this would be one of the biggest projects of my life, so I started reading, and planning, and scheming.  7 months after making the decision to construct a teardrop, I actually ordered a custom trailer and had the side templates cut from a CNC machine.  This blog will be my journal as I progress through the build process, hopefully making it easier for others in the future for their builds.

Choosing a Design



After making the decision to build a teardrop trailer, I needed to decide on the shape and style of teardrop that I was going to build.  I instantly made the decision when Google'ing teardrop trailers that I would make a woodie and saw this amazing teardrop.  Not even 30 seconds into my initial search, I came across the image of the teardrop below, and knew that mine needed to have the same classic wooden boat feel.  Working as a Lake Rescue employee for the University of Wisconsin Lifesaving Station for over 20 years has taught me to appreciate the old Correct Craft wooden boats.  That is what this tear reminded me of.


Then after spending months on the TNTTT.com forum researching teardrops, I fell in love with the shape of the ATMA Travelear.  The great thing about the teardrop forum is the helpful people who frequent the site.  The designer of the ATMA Travelear was gracious enough to not only share his trailer plans with me, but also the files he used to cut this trailer templates on a CNC machine.  In exchange, I cut his trailer logos in vinyl, in thanks for sharing his design. Having a CNC resource will not only save me time in the long run, but have a more precise build.  Dave's trailer is skinned in aluminum and has that old school art deco feel.  Mine will have the same shape, but be skinned in wood.


Building Space
I also knew that I would need additional space in my garage to even attempt this build.  After 7 years of accumulating stuff, and "storing" it in the garage put me in a pickle.  Step one was clearing out any unused junk, and moving seasonal items somewhere else.  I purchased a 8'x12' storage shed for my side yard.  Unfortunately, storage sheds are not free and I needed to organize and store all my non-seasonal equipment in here, which put a delay in the teardrop build to the spring of 2013.

In the meantime, I modified the ATMA Travelear's plans slightly and started creating my own drawings in Illustrator and Google Sketchup.  Sketchup is pretty easy to learn using online tutorials, and fit my needs for creating deck profiles and high level digital mockups of the teardrop.  Whether you use a cocktail napkin, or create precise engineering documents using AutoCad, I highly recommend having some type of drawing to create a plan.   

Here is the Google Sketchup model of my teardrop:

Having spent so much time pouring over the internet finding resources and information on teardrops, parts, camping accessories, build techniques, and design, I now am officially "Locked-in" with this project.  I wake up after dreaming about my teardrop build.  It's no longer a hobby, but an obsession.  I plan on sharing my notes, triumphs, failures, and overall build journal through this webpage to help document my progress and hopefully help someone in the future of their build.  I plan on using the expertise over at TNTTT.com and hope to get this teardrop camp-able sometime in 2013.  I also now know what "teardrop time" is, and accept that no matter how hard I try, there will be delays in the process.  

Current Build Codename:  Grillenium Falcon.