How much will it cost to build? 

Let me begin with a question I receive regularly; “How ‘cheap’ can I build an Explorer Box?”  From my perspective, if the only reason you’re planning on doing it yourself is to save money, you may not have the most rewarding experience.  However, combining reduced cost, a mechanical aptitude and a personal satisfaction from creating something with your own two hands; that’s a recipe for success.   That said, there is a range of ways to successfully build an Explorer Box, some more economical than others. 

Entry level cost of building an Explorer Box

(based on material cost Jan ‘08)

 Frames

An Explorer Box is built on a 4’ x 6’ frame.  Our recommended no-welding required option is Magenta Trailer’s bolt-together square tubing frame kit available for about $800 shipped.  Another adequate option for on-pavement only towing are bolt-together c-channel frames for $400-$500; although most kits are 4’ x 8’ and require some modifications.  If you’re a skilled welder, you can build a frame for around $300 in materials. I also regularly see suitable used flat bed trailers for as little as $200 on craigslist.       

Wood

You’ll need about $50 worth of clear grain fir or pine 1x3(4) for corner and shelf blocks.  You have a few trade-offs to consider when choosing your plywood.  When building, I use ACX Radiata Pine for the floor, marine BS1088 Okoume for the sides and top, and cabinet grade Baltic Birch for the shelves.  This combination saves 30-40 lbs, is very attractive with a clear finish and costs about $270.  Another option is to use ACX Fir or Pine plywood throughout. If you don’t mind the appearance differences, especially the “C” face on the inside and additional weight this way costs about $120.   

Finish type

This is another area with many choices.  On one end of the spectrum you could go with water-based Acrylic Latex (house) paint inside and out for around $50.  I have not personally used it for a trailer box, but if you search the internet, you’ll find a number of small boat building sites promoting its use.  If you think about it, your house is exposed to the elements day in and day out, the last time I painted mine was 10+ years ago and it still looks good.  For a durable colored exterior finish, I use a roll-on bed-liner material called Durabak, it runs about $150. For a clear exterior finish, I use Epifanes brand marine varnishes, it runs about $110.  For the interior I use quality polyurethane like General Finishes, it runs about $50.  For an added measure of moisture protection I also like to seal the exterior with Smith Companies CPES, it run about $60.

 Miscellaneous

There are a number of items like hardware, hinges, door latches, tongue and stabilizer jacks, glue, sandpaper, door seals, etc. that run about $250 regardless of your build method.  Although, if you use stainless steel hardware expect to spend an extra $50