There are Web sites throughout the world containing
pictures of mechanical calculating machines. Not many such sites have details of the
internal workings of such machines, although collectors and hobbyists like to endeavour to
restore them. Without specific information this task can be risky and damage to the
machine may result. The enclosed pictures and drawings The enclosed pictures and drawings
cover a model WM (War Model) Comptometer and are
provided to assist such hobbyists and enthusiasts. The information should be used in
conjunction with information at http://www.dotpoint.com/xnumber/comptometer.htm.
The author wishes to thank Philips for allowing the use
of a Digital camera for the pictures. It is worth noting that the largest problem
encountered was the removal of pivot shafts that had been bonded to the parts by years of
inactivity. These were removed as the job progressed by copious use of CRC 2.26 or CRC
5.56 sometimes leaving the shaft and its parts to soak overnight. The shafts were then
gently hammered through with a similar size 'follow through shaft', or one a size smaller.
After removal the shafts were cleaned of all residue using very fine Wet and Dry Emery
Cloth soaked in oil. The shafts were then replaced and dismantling of the area concerned
continued in the normal way with follow through shafts 'borrowed' from earlier in the
process. Vagabond is not sending me some follow through shafts to assist me in other
projects. |
This image shows the machine with
case removed ready for starting on the disassembly. The thumbnail pictures, although of
poor quality illustrates the content of the larger JPEG image for those who wish to
collect and modify the images
GET 'Larger images of the thumb nails are approx. 20~25K
size', an important factor to know if you are grabbing any of them, |
The Numeral wheel shutters and subtraction cut
off lever were removed and placed in order in front of the machine. These will later be
moved in order to one side so that we can continue the saga.
GET
'details of machine with Numeral wheel shutters and Sub-cut-offs removed' |
The safety shaft, a suitable piece
of flower wire of approximately the right gauge, was inserted into the rackframe actuating
cranks. The front toggle shaft was removed in preparation for the removal of the
rock-frame. All the Intermediate gears were dropped down alongside the Carrying gears and
the Rockframe and Intermediate Gear shafts and follow through rod removed. This allowed
the rock frame to toggle forward as in this image. The two blank intermediate gears were
deliberately moved from the two right positions to the left positions for the purpose of
clarity.
GET
'Show larger image of Rockframe forward' |
By rocking the 'RockFrame" on
the front Rockframe toggles it pivots under the frames front upper spacers. It should
toggle freely and can be pivoted backwards and forwards a number of times to allow
familiarisation to give you the feeling for removal. Once confident rock the frame forward
and remove it; as illustrated. Very likely the carrying gear shaft and locking dogs will
be gummed up but this does not concern us at this time. If you remove the intermediate
gears you can turn the Rockframe about in your hands, quite safely to examine it. Later we
will describe its function. You will note in this image the first four numeral wheels and
numeral wheel shutters have been removed. This was done merely to illustrate that the
Rock-Frame can be removed with or without the Numeral wheels in the machine.
GET
'Rockframe is removed and placed on bench top' |
All the numeral wheels have been
removed and placed to one side with the parts removed earlier and we are moving in to
position to remove the Carrying Bell Cranks, Latch Lifters, Backstops and Backstop
Springs. Look into the mechanism as this time and note the backstop springs pivot on the
shaft inside the actual backstop bearing. The springs are under tension and if the shaft
was to be removed with due care the springs would fly all over the place. You can if you
wish unlatch all the spring ends from under the frame. I elected to use a follow through
shaft place my hand over the front of the column I was working on and slid the shaft out.
Almost invariably the spring would hit my finger, the backstop would drop under the
machine with the sprint, the Bellcrank would swing forward on its spring and the latch
lifter would also fall out. Carefully unhook the Bellcrank spring at the bellcrank, or if
you wish use a follow through shaft and release the top end of the spring (this is
harder). Place the parts in columnar order at one side. If you wish you can check if the
rollers on the bellcrank turn freely. The hair springs are easily pulled of the pivot stud
but this is not necessary.
GET
'Showing numeral wheels removed' |
The accumulators can now be removed
by roving the shaft to the left one column at a time. In this image we show four
accumulators dropped down ready for placing at one side in columnar order. Before removing
the ALL the accumulators it is worth while dropping three, or four as in this case. Pull
the accumulator apart and note it consists of a pinion and ratchet, and lantern wheel (or
pin wheel) attached to a second gear. The pinion and accumulator are held together by a
'sintered bronze', I assume, tube. The ratchet is attached to the body of the accumulator
and a fine spring provides the tension. Note also A VERY IMPORTANT POINT the Pinion has a
deep tooth. This tooth must be one tooth forward of top dead centre on reassembly; when
the segment levers are up. Familiarise yourself with the deep tooth and its position
before removing all the accumulators. NOTE also the bellcrank springs, take care not to
catch these on your clothes and stretch them.
Four
accumulators are dropped and deep tooth examined for future ref... |
The accumulators safely out of the
way we can now tackle removal of the keys and keyplate. The keys are held in place by
keypieces with a key piece spring that also works at the return spring for the individual
keys. NOTE the springs have different tensions in each position, thus a nine key spring is
much lighter than a one key. The springs can also inflict considerable damage should they
hit the face or eye as you work. So wear specs' or 'safety goggles' as you remove the
keyspring or flex the keypieces. It is well to note that the keypieces themselves do not
have to be removed to remove a key. With a pair of fine short nose pliers you can grab the
left-hand leg of the keypiece with the spring inside the frame piece and tilt the keypiece
the key can then by lifted out of the plate. This is repeated until you have all the keys
removed. In this case four rows have been removed. The machine was stood on its rear end
during removal of these rows. Vagabond often refers to the numeral fill oozing from the
keytops; note this on the No 2 Keytop.
Shows
four columns of keys removed' |
Once all the keys are removed you
will find the top plate is held down on to the frames by three shafts with folded ends, in
the case of ex-sterling machines, and two shafts in the case of machines that were always
decimal. Removing these shafts allows the keyplate to be removed (on an 'F' 'H' or 'J'
machine you simply remove the keyplate screws, after removing the keys, and trip the
toggle on either side of the keyplate at the rear. It should be noted that model 'H' and
'J' are easier to work on as the square frame does not tend to want to go its own way and
the machine fall over backwards. On the 'F; the accumulators section is somewhat
different, Vagabond is to send me a machine to refurbish and this may be a future project.
All the manual Comptometer machines are similar and once you have seen the workings of one
the rest are not so difficult. As the models climbed up the alphabet they got
progressively more complex and the WM in this project is a difficult as you are going to
get, the 3D11 being the last manual Comptometer made was the next model.
A
'shot' showing all those things you wanted to see but always remained hidden... |
It is the authors plan to continue this project and explain the
removal of Segment lever, Keystop levers and Trigger mechanism including showing how to
check the adjustment of the various parts. To prepare you for the next run some images are
attached for those wishing previews without any text. Later I will add the text. As you
will note the machine was pulled right down to its frame and reassembles adjusting and
checking as the machine was refurbished. For those who had doubts it now clicks over like
a fine watch although it still has the dreadful smell of rancid oil. Normally all the
parts would have been washed out in mixture of Kerosene & Shellite or some similar
cleaning fluid. Although the challenge was there my desire to avoid getting filthy dirty
was greater than the desire clean the parts to provide the information.
Later more images will be added. It is also planned to do a similar
project using a Walther and who knows maybe Busicom and some electronic machines, starting
from basics. THE FUTURE IS AHEAD and retirement may give me the time, although current
indication suggest it will not
Clearing
handle side removed...
Segment
lever springs and trigger bell crank...
Segment
Lever coming out from under machine...
Segment
Lever Out...
Segment
Lever and Part Keystop Lever...
View
from above showing all rows same or similar on left are the trigger bell cranks and
springs on centre horizontal retainers and right accumulator locking hooks, accumulator
pinion ratchets...
It now time to finish for the day. I will continue later. The eyes
and mind get tired. For those who use Telepro they can download all the images and have a
preview. Some images still have to be uploaded and this will be done as soon as time
allows For others who are especially interested they tell me patience is a virtue.
|
Section last updated 16th
May 1999 by Ray Mackay |