July 4th, 2014 - the owner (Don) was complaining that the main 
tube was canted about 2 degrees to the right.  So today we dismantled 
it.  We removed the rack, wheels and axles, the seat, and disconnected 
the shifting cable.  We inverted the frame, I was going to use a 
hacksaw, but instead used the cutting wheel on the 4-1/2" hand grinder. 
 I cut from the bottom at the point where the main tube connects with 
the rear unit ... but not quite all the way through ... just short of 
the top re-enforcing plate. Cut the support tubes from the seat back 
tube, and cut off the seat mount unit.  So, with the main tube only 
connected to the rear unit by the top re-enforcing plate, put it upside 
down in a vise, checked for level on the main tube,  then torqued 
(twisted) the rear unit until it was level with the main tube.  That 
re-enforcing plate is pretty tough (1/8" thick) and with Don pushing up 
on one side while I applied my weight pushing down on the other side.  
It took us 3 attempts before we finally moved it enough to the proper 
position.  Then welded it back together.  Adjusted and welded back on 
the seat tube support tubes, welded on a new seat mount configuration 
(with a little more rearward angle to the seat), and welded on a roller 
to support the bottom return part of the chain so it doesn't hang down 
and swing back and forth.  Bolted the wheels, axles, and cargo rack back
 on.  Then we cable-tied a basket to the rear cargo rack for the owner 
to put groceries in when he goes shopping ... or books when he goes to 
the library.  And finally hooked back up the shifter cable after making 
an alignment adjustment to the rear derailleur mount.
I'm talking about being exhausted!
The above photo is the re-completed modified delta trike ... 
This is the lower chain roller ... when forward pressure is placed on 
the pedals, the top part of the chain sits about an inch (2.5 cm) above 
the roller unit.  There is a shield over the roller to keep the chain 
from hopping off the roller (had that problem before on another 
recumbent that I built).
Looking at the area where all the work was concentrated today.  Right in
 the middle you can see the silver "top re-enforcing plate" in front of 
the rack (the plate I didn't cut through).  This is where all the critical 
action took place.
In this photo, there is a better view of the seat mount (above the 
basket) ... and you can see the chain roller down in front of the seat.
Saturday, July 5, 2014
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