The Ladder Bike trailer

Here is a set of photos, and short notes, of the interesting parts of my Ladder Bike Trailer.

These were requested by my friend Emma, who helps coordinate the wonderful new “Bicester Green” – a Sustainability, Resource and Training centre in Bicester, not far from Oxford.  She is going to make a bike trailer for the centre, which will also be available for hire.  Bicester Green has workshops, shows films, taches repair skills, repairs furniture and electrical equipment, etc.

For an introduction to the Ladder Bike Trailer, please go to Stig’s Bike Trailers page and scroll down to the 4th trailer.  This page is a continuation, going into more detail on the joints, attaching points and other aspects.

Here is a photo of the trailer’s maiden voyage, before it had been painted in linseed oil.  As you can see it is a wide boat-shaped wooden ladder suspended at saddle height on two front forks.  A big blue net is hung below the ‘steps’ as a sort of lower carrying level – great for boxes, bags and people to lie it very comfortably.  The steps are a bit like a ladder for a good reason – I made this trailer to use as a ladder: I am regularly painting murals and having to take a separate ladder on a bike-trailer full of paints was a drag.  So instead I can now use the trailer AS a ladder.  Being wide and heavy is a good thing as it makes the ladder more stable.  I have also used this ladder to help get up into trees, to harvest fruit, or remove dead branches.

The tricky bit was devising a simple yet strong way to join the front forks to the wooden walls.  Joining metal pipes to wood is never straight-forward.  I drilled two holes in the upper steel pipe of each front fork.  Then I built a strong wooden block with a hole for that pipe to slide up into.  Two strong 8mm bolts, held on with lock-nuts on top of extra-large washers go through the wooden block and through the two holes in the steel pipes of the front forks.  This seems ed to work very well, although the whole joint is quite weighty.  If I did this again, I would use less wood, saving on weight and bulk.  Here is a view of this join:

I think one of the weakest points of this trailer is the top of the front forks, just before they go into this wooden block.  To reinforce this weak point I decided to add a pair of heavy-duty shelf-brackets underneath screwed into a new plywood floor that runs between the two forks.  Each bracket is attached to its front fork using gaffer tape, then a heavy-duty jubilee clip, then wrapped in gaffer tape again.  The first layer of gaffer is to stop the jubilee clip from sliding or from scratching the painted metal work.  The final layer of gaffer is to stop the clip from scratching passengers, (and to hide this ‘clumsy’ addition).

Here is one of these two reinforcing brackets seen from the other side:

Here is an old photo of the trailer carrying a bunch of old IT boxes, a dead cathode-ray monitor, etc, to Redbridge, my local Council’s “recycling” centre.

Joining the netting to the wooden walls was easier.  I just attached those really handy metal eye-plates that have 2 or 4 holes for screws.  Then I bunched up the netting and looped it onto a small shackle, locking that to the eye-plate.  These can be adjusted if the net ever needs to be loosened.  The metal eye-plates are also excellent places to attach a bungee.   Here are a few views of these net-shackle points:

At the front end of the trailer (above) are two large eye-plates.  This allows me to stick a bamboo pole through both, to hang a flag or banner or rain-proof roof.

This shackle is attached to a eye-ended bolt that goes straight through the ‘stern’ end of the trailer.  The white plastic pipe above is to hold a bamboo flag-pole.  With three such flag-holders we’ve been able to erect a three-pole banner-hanging rig above the whole trailer, as shown below:

The Ladder Bike Trailer is taken to the City centre for a demo against the Tar Sands, in 2010.  Three vertical bamboo poles support a long horizontal top-pole from which two banners are hung.  Other props, waterproofs, a small PA-system are carried in the trailer’s net layer.  Placards, a camera tripod and more banner poles were on the ‘steps’ level above the net.