The Thornton Windlass Innards
Copyright 2010 by James P. Riser
This web page was created to assist owners in the repair
of the last style of Thornton Windlass. The arbor on this model
differs greatly from the earlier models. I do not consider this
design an improvement.
When disassembling the Thornton, it will be seen that
the bottom spring sits in a separate case within the bottom of
the outer case.
The brass center piece sticking up is riveted through
the inner and outer cases and can not be removed.
The two cases are securely joined.
Riveted center
post.
The outside end of the spring hooks onto the inner
case wall. 
The inside end of this spring looks like this. 
The arbor slips down over the brass center piece.
The bent end of the spring shown above slips into the
slot of this arbor.
This is what secures the spring end.
If the reel is allowed to freely retract, the shock
can cause this or the other spring to jump out of the arbor slot
resulting in no tension on the reel drum.
This is the drum into which the secord spring fits
and onto which the thread is wound. 
The barrel for the second spring is shown here - outside
and inside with its spring. The inner end of this spring is bent
back on itself just like the other spring. It hooks into the same
slot as the bottom spring.
Shown below is how the springs hook onto the arbor
slot.
The top spring barrel is held in place within the drum
by 3 holes punched through the rim of the drum.
Shown here next to the arbor is the arbor bearing.
Here is a close-up
of the arbor bearing.
Notice that there are a number of staking tool marks
around
the ledge of the small brass circumference.
This is where the bearing was originally staked to
the
hole in the drum.
Allowing the reel to freely retract can cause this
to become
separated from the drum. This is a real problem with
the design.
This
is the inside of the drum hole where the arbor bearing was staked
holding the bearing and drum together.
Assembled things look like this. 
The smaller part of the arbor bearing will need to
be very delicately filed at the staking marks so that it will
once again tightly fit into the drum hole. Do not take off too
much brass! To reattach the brass to the drum can be problematic.
The drum with all attached springs in position must be slightly
lifted to raise it out of the case. Toothpicks may be inserted
to hold the drum in this elevated position. The drum hole area
and the discs of the bearing arbor must be oil free. Clean with
lacquer thinner, acetone, etc. Once the surfaces are clean and
the arbor bearing sunk into the drum hole, everything can be secured
with a drop of Loctite. The Loctite will flow by capillary action.
Do not use more than a drop or two or you can lock up the reel!
Preferred method of repair would be be micro TIG welding
the bearing brass to the drum (very expensive equipment).
Notice the arrow on the drum. It is turned in this
direction to wind the springs. Turning in the other direction
will unhook the inner ends of the springs! The thread is also
wound around the drum in this direction. 40 feet of thread is
plenty.
Thorntons are delicate and only fine clear oil should
be used for lubrication. Use only a few drops if needed.
If the arbor bearing has popped from the drum hole
on a Thornton, the drum will sit too low in the outer case and
rub making noise.
Good luck with this nightmare of a reel!