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multisumma22 [2017/04/28 00:11]
clodoveu
multisumma22 [2017/04/28 00:42] (current)
clodoveu
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 At about 10 kilos, the Multisumma 22 weighs almost twice as much as the Multisumma 20, a more recent relative of the Summa Prima 20. My unit has the usual color scheme for this family of machines, green and black, unlike my Divisumma 24, from Argentina, which is white and light gray. It looks just like the Elettrosumma 22, which has no multiplication feature. At about 10 kilos, the Multisumma 22 weighs almost twice as much as the Multisumma 20, a more recent relative of the Summa Prima 20. My unit has the usual color scheme for this family of machines, green and black, unlike my Divisumma 24, from Argentina, which is white and light gray. It looks just like the Elettrosumma 22, which has no multiplication feature.
  
-I purchased this machine in March 2017 at an online auction site. The vendor warned in a video that the motor was running, but the numerical keys were frozen. An original power cable was supplied. Its exterior appearance was good, the case was intact and all the keys were present. The back of the motor has a stamp with a date: May 29, 1962. +I purchased this machine in March 2017 at an online auction site. In Brazil, the Multisumma and the Elettrosumma are much rarer than the larger Divisumma 24. The vendor warned in a video that the motor was running, but the numerical keys were frozen. An original power cable was supplied. Its exterior appearance was good, the case was intact and all the keys were present. The back of the motor has a stamp with a date: May 29, 1962. 
  
-I disassembled a small part of the machine, including the paper handling mechanism, the ribbon mechanism and the motor assembly, so that inner parts of the mechanism could be reached for some cleaning using a jet of kerosene, applied with an airbrush and some air pressure. Then I approached each problem the machine had by identifying the parts of the mechanism that were involved in each faulty operation for further cleaning and adjustment. Multiplication was the hardest, as a long piece was bent from being pressed against a locked part of the mechanism. Another small lever, embedded deep inside the machine, was also slightly bent, making it miss multiplication factor counts and produce wrong results; it took me five days to find the source of this problem. ​+I disassembled a small part of the machine, including the paper handling mechanism, the ribbon mechanism and the motor assembly, so that inner parts of the mechanism could be reached for some cleaning using a jet of kerosene, applied with an airbrush and some air pressure. Then I approached each problem the machine had by identifying the parts of the mechanism that were involved in each faulty operation for further cleaning and adjustment. This took me from making it clear without locking up, then to adding subtracting with negative balance, and on to loosening all printer digits. Multiplication was the hardest, as a long piece was bent from being pressed against a locked part of the mechanism. Another small lever, embedded deep inside the machine, was also slightly bent, making it miss multiplication factor counts and produce wrong results; it took me five days to find the source of this problem. ​
  
 There was also a problem with a capacitor-resistor circuit that works around the machine'​s main electrical switch. The circuit is supposed to avoid sparking in the switch, but the old oil capacitor leaked and shorted out, and had to be replaced. This old capacitor was manufactured by Ducati, a brand currently associated with motorcycles (see [[https://​en.wikipedia.org/​wiki/​Ducati_Energia]]). Oil capacitors are rare nowadays, so I found a suitable polyester one, and now everything works very nicely -- although noisily! There was also a problem with a capacitor-resistor circuit that works around the machine'​s main electrical switch. The circuit is supposed to avoid sparking in the switch, but the old oil capacitor leaked and shorted out, and had to be replaced. This old capacitor was manufactured by Ducati, a brand currently associated with motorcycles (see [[https://​en.wikipedia.org/​wiki/​Ducati_Energia]]). Oil capacitors are rare nowadays, so I found a suitable polyester one, and now everything works very nicely -- although noisily!
- 
  
  
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 **c1962 Olivetti Multisumma 22 s/n M-203500 ** **c1962 Olivetti Multisumma 22 s/n M-203500 **
  
-Front view, after cleaning and revision.+External views, after cleaning and revision.
  
 {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_front.jpg?​500 | Front}} {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_front.jpg?​500 | Front}}
  
 {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_front2.jpg?​500 | Front}} {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_front2.jpg?​500 | Front}}
 +
 +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_side.jpg?​500 | Side}}
 +
 +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_back.jpg?​500 | Back}}
  
 A view of the motor, stamped with a production date: 29 May 1962. The yellow capacitor to the left is still the Ducati one. A view of the motor, stamped with a production date: 29 May 1962. The yellow capacitor to the left is still the Ducati one.
  
-{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_motor.jpg?​500 | As purchased}}+{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170413_multisumma_22_motor.jpg?​500 | Motor}} 
 + 
 +Internal views, taken while and right after cleaning. 
 + 
 +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170409_multisumma_22_cleaning3.jpg?​500 | Internal}} 
 + 
 +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170409_multisumma_22_cleaning2.jpg?​500 | Internal}} 
 + 
 +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​20170409_multisumma_22_cleaning.jpg?​500 | Internal}}
  
 As purchased, in March 2017. Not bad on the outside, numeric keys inoperative,​ most functions locked. As purchased, in March 2017. Not bad on the outside, numeric keys inoperative,​ most functions locked.
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 Some of the innovative and artistic ads for the Olivetti Multisumma 22 and Elettrosumma 22. Some of the innovative and artistic ads for the Olivetti Multisumma 22 and Elettrosumma 22.
  
-  ​{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Giovanni_Pintori-008.jpg?​120 | Ad}} +{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Giovanni_Pintori-008.jpg?​250}} 
-  {{http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Giovanni_Pintori-005.jpg?​120 | Ad }} +{{http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Giovanni_Pintori-005.jpg?​250 }} 
-  {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Multisumma_22_ad_3.jpg?​120 | Ad }}+{{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Multisumma_22_ad_3.jpg?​250 }}
  
 I put together an operating manual for this machine, I hope it helps anyone interested in bringing a Multisumma 22 or an Elettrosumma 22 back to life. I put together an operating manual for this machine, I hope it helps anyone interested in bringing a Multisumma 22 or an Elettrosumma 22 back to life.
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 {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Multisumma_22_manual_CADJ.pdf | Manual}} {{ http://​www.dcc.ufmg.br/​~clodoveu/​files/​Images/​Multisumma22/​Multisumma_22_manual_CADJ.pdf | Manual}}
  
-**More about this machine ​-- UNDER CONSTRUCTION**+**More about this machine** 
 + 
 +[[https://​www.youtube.com/​watch?​v=R242KWNhnvw | A video showing the Multisumma 22 in operation]]
  
 [[http://​www.vintagecalculators.com/​html/​olivetti_electro-mechanical_ca.html | An interview with Mr. Jay Respler, who worked for Olivetti-Underwood in the peak of mechanical calculators]] [[http://​www.vintagecalculators.com/​html/​olivetti_electro-mechanical_ca.html | An interview with Mr. Jay Respler, who worked for Olivetti-Underwood in the peak of mechanical calculators]]
  
 [[http://​www.johnwolff.id.au/​calculators/​Olivetti/​Olivetti.htm | John Wolfe'​s Web Museum, description of the entire Olivetti line along time]] [[http://​www.johnwolff.id.au/​calculators/​Olivetti/​Olivetti.htm | John Wolfe'​s Web Museum, description of the entire Olivetti line along time]]
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multisumma22.1493349109.txt.gz · Last modified: 2017/04/28 00:11 by clodoveu
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