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The design of 828 spools was unusual, if not unique. Most
spool designs used a flat flange with a keyed hole that engaged the takeup
mechanism. The core of 828 spools projects through the flanges and winding
notches are cut into the core ends. While the supply spool of most Bantams
usually sits in a basket that is pretty indifferent to the design of the
core ends, the winding knob's shank and its pins must closely mate with
the ends of the spool. The easiest option is to use an original for the
take up spool and your recreation as the supply spool. This isn't much
of a problem if you are doing your own processing and can recyle a few
spools so you have a fresh supply of new film.
We have identified two spool-making strategies. The first is easier and
is the obvious choice for supply spools that don't need end notches. The
second, more complicated approach is more appropriate if you need to make
a takeup spool that can engage the Bantam winding mechanism.
In using either technique, it is very useful to have an original 828 spool
as a model. In both procedures, it is important to space the washers perpendicular
to the tube and 35mm from each other to avoid edge fogging.
Materials (typically available at good hardware stores,
home suppliers or hobby shops)
- Rigid brass tubing (Don uses two sizes with the inside diameter of
the large the same as the outside diameter of the smaller). 828 cores
have an outside diameter of about 7mm.
- Brass washers with an inner hole the same size as the smaller brass
tubing. 828 rolls have flanges that are about 19mm.
- Epoxy or solder
Fitting - Don's
design uses two pieces of tubing, which simplifies accurately attaching
the flanges.
- Cut the larger diameter tube to exactly 35mm
- Cut a piece of the smaller diameter tube to about 42mm
- Cut four winding notches into one end of the smaller tube to engage
the winding mechanism. Try the tube with your camera to make sure it
engages the winding mechanism.
- Cut slots on each side of the tubing to thread the tongue of the backing
paper. You don't really need these for supply spools; you can just tape
the backing paper to the spool with masking tape. Depending on the fit
of the larger and smaller tube, you may be able to cut a slot in just
the outer tube and slide the paper between the walls of the tubes.
- Slip the inner tube into the outer tube and place a washer on each
end.
- Solder or epoxy the washer to the outer tube. You need a way to hold
the washers firmly against the shoulder created by the outer tube to
keep them perpendicular while you solder or epoxy.
Alternative Fitting
If you expect to use this spool as a takeup spool, it must closely replicate
the original. To do that I have made two small jigs--one to hold the assembled
spool in the correct position while epoxy sets and the second to hold
the tube while I cut slits for the backing paper. Here is a rough drawing
of the clamping jig I've made. If you have the right tools handy--a table,
band or miter saw and a drill press-- it will take 15 minutes.
- Cut a 35mm length of 2x2 with ends that are square to its sides.
- Drill a 7mm hole through the length of the block, making sure that
the hole is exactly perpendicular to the ends. The tube must slide into
this hole but be held so that it doesn't wobble in the hole. This is
easy with a drill press and difficult with a hand drill.
- Optional if you are using this as a takeup spool. Cut an
additional block just like the first. Drill a 7mm hole through the length,
then split it lengthwise. Use this half as a cradle for the tube while
you cut slots to thread the backing paper. I more or less successfully
did this with a rotary saw bit in a Dremel tool, but this requires a
steady hand and the proper safety equipment. If you will be using this
as a supply spool, it is easier to forego the slots and tape the backing
paper to the spool with masking tape.
- Cut two pieces of 3/4 inch pine or plywood so that their length and
width are the same as the ends of the block. These will be
placed over the ends of the tube during clamping.
- In the caps, countersink a 1/2 inch hole that is about the thickness
of the brass washer. Drill an 8mm whole in center of the countersunk
hole. The depth of the 8mm hole should be equal to the projection of
the tube out of the main block.
- This procedure uses only one piece of brass tubing 7mm in diameter
with a tube wall that is very close to that of an original 828 spool.
It is important to locate brass washers that fit snugly over the tube.
After placing the tube in the hole, place one of the caps over one end
of the tube. The block and the cap can now be placed in a vice so that
you can use a file or Dremel tool to form the notches in the tube that
will engage the winding shank/pins. You only need notches on one end
and if this will be a supply spool you can skip adding the notches altogether.
- When you have finished the notching, place a washer over each end
and spread some epoxy around the junction. Place some waxed paper or
scrap plastic sheet over the end of the spool assembly so that the cap
doesn't bond to the spool and place the caps over the spool ends. If
you prefer solder, you can use the jig and one end cap to hold the assembly
in position while you solder.
- For the epoxy method, clamp the assembled jig in either a woodworking
vice or a C-clamp. Only gentle pressure is needed.
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