Hello Tim! Another wonderful video! And it has lots of important information for me. I have a Divisumma 24 in which the division is no longer working... I have an enormous fear about causing damage In the machine while trying to repair it. I'm definitely not good in repairing things, as my machines are the very first opportunity I had to deal with such a complexity. Tim, I wrote a comment in a video in which you repair a Prima 20. I've acquired a Studio 45 typewriter and a Summa Prima 20 adding machine. And I can now tell you that these machines are fascinating and endlessly fun to operate just like you said! Searching for information wherever I could find about how they work, discovering and testing ideas was surely one of the most awesome experiences I've ever had! Thank you!
Hi Bruno, glad you're having fun with the Studio 45 and the Prima 20, it's a pity that the Divisumma 24 isn't working at the moment, but the main thing is that you have it - one day you'll manage to get it working again - the main thing is not to rush - if you don't feel up to tackling it at the moment, don't try. Instead, take on some simpler mechanical repairs to build up your experience and confidence first. It's reasonably likely that if your Divisumma was working and now isn't, that some old oil that had been freed up enough to get the machine working, has now set hard again, causing a part not to work - I've had that a few times, and most of the time I can get to parts without taking the whole machine to pieces, giving the offending part some more oil and heat and wiggling it until it's free again. Obviously, taking the entire machine to pieces and cleaning every bit of old oil and grease off would be a more thorough way of doing the job, but that's a pretty daunting and time consuming task for anyone. Anyway, I hope you carry on having fun with your excellent collection.
Hi Tim, great video! I'm blown away by the wonderful closeup shots of the mechanics in motion and your excellent explanations. For bringing these old sticky calculators back to life you do need only three things: patience, patience and patience 😉. Applying heat is really helpful, I often use it together with a 1:1 mixture of isopropyl alcohol and semi synthetic engine oil.
I was amazed the shot of the register worked as well as it did, the gap was so tiny, but I managed to get a bit of light in from the side which really helped. Oooh I'll have to try your Isopropanol and engine oil mix, that sounds good.
I just finished fixing a Marchant I, and although not a mechanical machine it was a nice break - havent had much time to work on my fridens but I have done a few minor repairs here and there. Your ability to navigate these with such knowledge is very impressive, im still questioning what most levers do in machines Ive had for years
Cheers ArcadeCarpet, unknown levers and the like can present quite a puzzle - you don't know what the lever should do or if it's actually doing it's thing already and you haven't noticed, and that makes it pretty difficult to figure out why it isn't working if you don't even know what it should do in the first place!!!! I'm very familiar with that situation, even on this Olivetti, before I fixed it I didn't know how the multiplier should work (as it happened it was exactly as you might expect it to work), but luckily I found an old sales brochure or something online which gave a brief description of what each key should do - the brochure was all in a foreign language but luckily we have things like the google camera/translate facility which really helped in that situation. Cheers for watching and commenting, and keep having fun with your Marchant and Friden machines.
Another great video Tim. Having just finished completely dismantling, cleaning and reassembling a Summa Prima 20, it is interesting and, of course, inevitable how much of that machine's technology is used in the Multisumma. Same method for driving the print wheels, for moving and inverting the register block, for storing and transferring the entered number onto the racks and therefore into the register, and I also recognise some of the interlocks. You realise I'm going to have to go and lift my Divisumma 24 off its base to see if it uses the same sort of mechanism as the Multisumma 'memory' to store the multiplicand.
Hi Simon, as you say, it's somewhat inevitable that they would have used the same technology for both the Prima 20 and the Multisumma 20, but never the less it's still interesting to actually see it. It would be reasonable to assume that the Divisumma 24 uses the same method for the multiplication, but you never know, they might have tried something different. I can't believe that I didn't spot the fact that it stores the result of the previous multiplication - I'd noticed that it didn't reset the multiplier racks to zero but I failed to make the mental leap to figure out it was actually a useful function!!!
The Divisumma 24 uses a constant memory as one of the factors of the multiplication. After every multiplication, this memory does not erase itself, so you can do multiplications with a constant factor. Also this memory can be used as a constant sum, subtract, and can be set while printing a total or a subtotal. And also, the quotient of a division is formed in this memory.
Yeah, I love working on stuff like these machines - I've always fancied a Teletype machine, but unlike mechanical calculators they tend to be quite expensive, plus they're massive and I haven't really got space. Thanks for watching Ben.
Yep, I do rather like good old mechanisms like this, and they're a bit addictive to work on. I still want a Teletype machine, but they're kind of rare and expensive, and I definitely don't have room for one........
Wonderful video as usual! The automatic total transfer in the multiplication is a nice thing, but not always present in every Multisumma! The first series (round keys) does not have that, and also some of the second series (square keys) do not... Of course when I discovered about this I bought a second series, and of course it didn't have that transfer mechanism...
Coo, once I'd actually discovered it, I just assumed that the transfer mechanism was present in all Multisummas, I guess I got lucky there. Thanks for that extra gem of information Nicolò, that will definitely help if people get in touch with me to ask why their transfer mechanism isn't working like mine!!!!
Hi John, I can well imagine the Tetractys being a bit of a pain, but on the other hand, what a lovely machine to have in your collection, and I bet it's great on the odd occasion that it chooses to work!
If you've enjoyed this video and want to see more, here's my playlist of mechanical calculator (plus the odd electronic one) videos: ruclips.net/p/PL8E7qepyRm5BhvfGlDEM0xPnftwIHBYQD
Hi Tim, I have a machine similar to this one. It's an ivrea 20 electric. I have found a few sticky parts and got them moving. All the keys work except the number pad. When I press a number the indicator stays where it is. You can see the linkages moving and you can hear the pins being pushed on the matrix. The silver bar you mentioned in the video is clean and I have used penatrating spray to try and get it moving. Any help would be appreciated. Thanks.
Hi Wavydave Hill, the keyboard mechanism should be pretty similar or even identical to my machine, so hopefully, with a bit of detective work we'll get yours running. I presume the indicator for the numbers is all the way to the right, ie no digits have been entered. In that position, assuming the matrix which runs on the silver bar is free to move, you should be able to move the matrix about a millimetre to the right and then it should spring back to where it started (viewing from the front of the machine by the way). It won't move the other way until a key has been pressed. If it won't move that little bit, it could still be gummed up with old oil - that sliding bearing has quite a large surface area for the old oil to stick it solid. If the matrix will move that small amount to the right, but doesn't move back to the left when you let go, it could be that it's still sticking, or the spring that pulls it to the left is broken, disconnected or missing. Anyway, have a quick look at that and let me know what you can find. Feel free to email me (address in the "about" tab on my channel), that way you can always send photos or video if required, because it's often easier to see a problem than describe it!!!
@GrumpyTim Thanks for the reply. What is your email, I couldn't see it. I tried moving it to the right but it wouldn't move. What I have found is the clamp around the block that moves is attached to a lever with a roller at the end. There is a arm which is connected to a rear cam. This is on the left of the machine look at it from the front. This arm with a roller on it seems totally jammed. It seems to go in the keyboard. Is there something that could be jamming it. I will send a picture of this leaver. Thanks.
@@wavydavehill8520 I'll take a look at my machine tomorrow to refresh my memory. In the mean time, my channel name at my channel name .com should get you there, obviously inserting the name of my channel! I tend to get about a million spam emails if I leave my email address in the comments.
Hi Wavydave Hill, definitely a few photos would help - the am with the roller is used to drive the matrix back to it's rest position after a calculation. At rest, there should be no movement in one direction, but you should get about 1mm of movement the other way (it's directly connected to the matrix so it's the same movement you'll be feeling. However, if the matrix is still seized on it's shaft you won't get any movement. Likewise, if, for some reason, the matrix has been pushed hard against the end stop, then you won't get movement in either direction.
Hey there i have a Olivetti summa prima 20 with an keybord issue 5:14 mine wont move at all no matter what key i press. I have checked everything and oiled it but it just wont work pushing it by hand dose make it work sometimes. May i know what kind of lssue this is .
Hi, can I just check which position the pin matrix is in at the moment? Looking from the front, the pin matrix, and the little indicator in the window which is attached to it, should be over to the right. As you enter each number, the pin matrix, complete with the little indicator should move one place to the left. The keyboard clearing lever should move the pin matrix back to the right without having to crank the handle. There's a spring that pulls the matrix to the left and some levers that move it back to the right. Is yours moving to the left at all or is it just stuck on the right hand side?
@@GrumpyTim np i will make a video later. Have u heard a machines called 'FACIT 1204' i have that but a RARE one its looks same but the name tag were not same mine has the tag Odhner.
Greetings from Portugal from a recent fellow enthusiast! Great video, bought a Multisumma 20 in what looked a great shape, but many parts were not working... following your general directions in this video I've managed to put it ALMOST in fully working condition! The only problem I'm having now, that renders the machine useless: both in addition and multiplication the machine does not carry decimal increments from the previous number operation. Example: ADDITION 12+13=25 (OK) BUT 12+19=21 (does not carry the 1 from previous position into the next ) ----- 24*2=48 (OK) BUT 28*3=64 (SAME, does not carry the 2 from previous position into the next ). Many parts were seized up... Do you have any clue of the offending part? All the best and thanks for sharing your knowledge on these amazing beasts.
Hi David, I'm away from my Multisumma for a few days, but I'll think about your problem and if necessary take a look at my machine when I'm reunited with it next week, then I'll get back in touch. In the meantime, could you add the fairly normal 123 + 456 + 789 + 987 + 654 + 321 - do it several times and make a note of the result each time - it might give me a bit of an idea, or it might not help at all - my hunch is that you'll get fairly random results but I could be wrong and you end up with the same every time.
I had another little thought, try the same thing but add 3 zeros, ie 123000 + 456000 and so on - that way, if it's only the third column that's not carrying correctly, you might get the correct result, or it might be even worse. You could even try with 4 zeros, after that we should have more of an idea whether it's one column or the entire register that's playing up.
@@GrumpyTim Thank you for your generous help! Will try it tomorrow and let you know - I managed to find 2 service manuals online, one in English, the other in Italian, very detailed for problem solving and practical work to solve them... but if I have to make an open heart surgery to the Multisumma register or accumulator I fear the worst... will try it nonetheless and learn something in the process, even if so much above my present skill level!
@@GrumpyTim Greetings again! Finished the test, and again got a consistent same result every time: BLANK total! Good Lord, not even zeros... I'm totally baffled! Even not being able to carry it should had gave me some zeros: if I summ 950+50, for example, I am given an infamous 900 as a result! Thank you for all your patience with an internet stranger in mechanical distress!
![MISSING: SLIM SHADY [Expanded Mourner’s Edition Trailer]](http://i.ytimg.com/vi/xh8qgHrOO1g/mqdefault.jpg)
Hello Tim! Another wonderful video! And it has lots of important information for me.
I have a Divisumma 24 in which the division is no longer working... I have an enormous fear about causing damage In the machine while trying to repair it. I'm definitely not good in repairing things, as my machines are the very first opportunity I had to deal with such a complexity.
Tim, I wrote a comment in a video in which you repair a Prima 20. I've acquired a Studio 45 typewriter and a Summa Prima 20 adding machine. And I can now tell you that these machines are fascinating and endlessly fun to operate just like you said! Searching for information wherever I could find about how they work, discovering and testing ideas was surely one of the most awesome experiences I've ever had!
Thank you!
Hi Bruno, glad you're having fun with the Studio 45 and the Prima 20, it's a pity that the Divisumma 24 isn't working at the moment, but the main thing is that you have it - one day you'll manage to get it working again - the main thing is not to rush - if you don't feel up to tackling it at the moment, don't try. Instead, take on some simpler mechanical repairs to build up your experience and confidence first. It's reasonably likely that if your Divisumma was working and now isn't, that some old oil that had been freed up enough to get the machine working, has now set hard again, causing a part not to work - I've had that a few times, and most of the time I can get to parts without taking the whole machine to pieces, giving the offending part some more oil and heat and wiggling it until it's free again. Obviously, taking the entire machine to pieces and cleaning every bit of old oil and grease off would be a more thorough way of doing the job, but that's a pretty daunting and time consuming task for anyone.
Anyway, I hope you carry on having fun with your excellent collection.
Hi Tim, great video! I'm blown away by the wonderful closeup shots of the mechanics in motion and your excellent explanations.
For bringing these old sticky calculators back to life you do need only three things: patience, patience and patience 😉.
Applying heat is really helpful, I often use it together with a 1:1 mixture of isopropyl alcohol and semi synthetic engine oil.
I was amazed the shot of the register worked as well as it did, the gap was so tiny, but I managed to get a bit of light in from the side which really helped. Oooh I'll have to try your Isopropanol and engine oil mix, that sounds good.
I just finished fixing a Marchant I, and although not a mechanical machine it was a nice break - havent had much time to work on my fridens but I have done a few minor repairs here and there. Your ability to navigate these with such knowledge is very impressive, im still questioning what most levers do in machines Ive had for years
Cheers ArcadeCarpet, unknown levers and the like can present quite a puzzle - you don't know what the lever should do or if it's actually doing it's thing already and you haven't noticed, and that makes it pretty difficult to figure out why it isn't working if you don't even know what it should do in the first place!!!! I'm very familiar with that situation, even on this Olivetti, before I fixed it I didn't know how the multiplier should work (as it happened it was exactly as you might expect it to work), but luckily I found an old sales brochure or something online which gave a brief description of what each key should do - the brochure was all in a foreign language but luckily we have things like the google camera/translate facility which really helped in that situation.
Cheers for watching and commenting, and keep having fun with your Marchant and Friden machines.
Another great video Tim. Having just finished completely dismantling, cleaning and reassembling a Summa Prima 20, it is interesting and, of course, inevitable how much of that machine's technology is used in the Multisumma. Same method for driving the print wheels, for moving and inverting the register block, for storing and transferring the entered number onto the racks and therefore into the register, and I also recognise some of the interlocks. You realise I'm going to have to go and lift my Divisumma 24 off its base to see if it uses the same sort of mechanism as the Multisumma 'memory' to store the multiplicand.
Hi Simon, as you say, it's somewhat inevitable that they would have used the same technology for both the Prima 20 and the Multisumma 20, but never the less it's still interesting to actually see it. It would be reasonable to assume that the Divisumma 24 uses the same method for the multiplication, but you never know, they might have tried something different. I can't believe that I didn't spot the fact that it stores the result of the previous multiplication - I'd noticed that it didn't reset the multiplier racks to zero but I failed to make the mental leap to figure out it was actually a useful function!!!
The Divisumma 24 uses a constant memory as one of the factors of the multiplication. After every multiplication, this memory does not erase itself, so you can do multiplications with a constant factor.
Also this memory can be used as a constant sum, subtract, and can be set while printing a total or a subtotal.
And also, the quotient of a division is formed in this memory.
Thanks again Nicolò, your knowledge of these machines is always very much appreciated.
They are fascinatingly complex but interesting machines.
Yeah, I love working on stuff like these machines - I've always fancied a Teletype machine, but unlike mechanical calculators they tend to be quite expensive, plus they're massive and I haven't really got space. Thanks for watching Ben.
@@GrumpyTim Perhaps my problem is I just squeeze a bit more in.
@@BensWorkshop We''re kind of overflowing with stuff here, but there's always a way to fit in just one more project!!!!!
Such a satisfying mechanism to watch!
Yep, I do rather like good old mechanisms like this, and they're a bit addictive to work on. I still want a Teletype machine, but they're kind of rare and expensive, and I definitely don't have room for one........
Wonderful video as usual! The automatic total transfer in the multiplication is a nice thing, but not always present in every Multisumma! The first series (round keys) does not have that, and also some of the second series (square keys) do not... Of course when I discovered about this I bought a second series, and of course it didn't have that transfer mechanism...
Coo, once I'd actually discovered it, I just assumed that the transfer mechanism was present in all Multisummas, I guess I got lucky there. Thanks for that extra gem of information Nicolò, that will definitely help if people get in touch with me to ask why their transfer mechanism isn't working like mine!!!!
The Olivetti Tetractys 24 is an absolute nightmare to work on. As soon as I get mine running, another fault rears its head!
Hi John, I can well imagine the Tetractys being a bit of a pain, but on the other hand, what a lovely machine to have in your collection, and I bet it's great on the odd occasion that it chooses to work!
If you've enjoyed this video and want to see more, here's my playlist of mechanical calculator (plus the odd electronic one) videos: ruclips.net/p/PL8E7qepyRm5BhvfGlDEM0xPnftwIHBYQD
Hi Tim, I have a machine similar to this one. It's an ivrea 20 electric. I have found a few sticky parts and got them moving. All the keys work except the number pad.
When I press a number the indicator stays where it is. You can see the linkages moving and you can hear the pins being pushed on the matrix.
The silver bar you mentioned in the video is clean and I have used penatrating spray to try and get it moving. Any help would be appreciated. Thanks.
Hi Wavydave Hill, the keyboard mechanism should be pretty similar or even identical to my machine, so hopefully, with a bit of detective work we'll get yours running. I presume the indicator for the numbers is all the way to the right, ie no digits have been entered. In that position, assuming the matrix which runs on the silver bar is free to move, you should be able to move the matrix about a millimetre to the right and then it should spring back to where it started (viewing from the front of the machine by the way). It won't move the other way until a key has been pressed. If it won't move that little bit, it could still be gummed up with old oil - that sliding bearing has quite a large surface area for the old oil to stick it solid. If the matrix will move that small amount to the right, but doesn't move back to the left when you let go, it could be that it's still sticking, or the spring that pulls it to the left is broken, disconnected or missing.
Anyway, have a quick look at that and let me know what you can find. Feel free to email me (address in the "about" tab on my channel), that way you can always send photos or video if required, because it's often easier to see a problem than describe it!!!
@GrumpyTim Thanks for the reply. What is your email, I couldn't see it.
I tried moving it to the right but it wouldn't move.
What I have found is the clamp around the block that moves is attached to a lever with a roller at the end. There is a arm which is connected to a rear cam. This is on the left of the machine look at it from the front. This arm with a roller on it seems totally jammed. It seems to go in the keyboard. Is there something that could be jamming it. I will send a picture of this leaver. Thanks.
@@wavydavehill8520 I'll take a look at my machine tomorrow to refresh my memory. In the mean time, my channel name at my channel name .com should get you there, obviously inserting the name of my channel! I tend to get about a million spam emails if I leave my email address in the comments.
Hi Wavydave Hill, definitely a few photos would help - the am with the roller is used to drive the matrix back to it's rest position after a calculation. At rest, there should be no movement in one direction, but you should get about 1mm of movement the other way (it's directly connected to the matrix so it's the same movement you'll be feeling. However, if the matrix is still seized on it's shaft you won't get any movement. Likewise, if, for some reason, the matrix has been pushed hard against the end stop, then you won't get movement in either direction.
Hey there i have a Olivetti summa prima 20 with an keybord issue 5:14 mine wont move at all no matter what key i press. I have checked everything and oiled it but it just wont work
pushing it by hand dose make it work sometimes. May i know what kind of lssue this is .
by looking down i found theres an hook that hold the keybord the lssue is the hook just keept go to an wrong position and jam up the head.
Hi, can I just check which position the pin matrix is in at the moment? Looking from the front, the pin matrix, and the little indicator in the window which is attached to it, should be over to the right. As you enter each number, the pin matrix, complete with the little indicator should move one place to the left. The keyboard clearing lever should move the pin matrix back to the right without having to crank the handle.
There's a spring that pulls the matrix to the left and some levers that move it back to the right. Is yours moving to the left at all or is it just stuck on the right hand side?
@@GrumpyTim I dont really know how to tell mabye i will make a video and tag u
Yeah, that would be good, you can just let me know here once you've uploaded a video and I'll take a look to see if I can spot anything obvious.
@@GrumpyTim np i will make a video later. Have u heard a machines called 'FACIT 1204' i have that but a RARE one its looks same but the name tag were not same mine has the tag Odhner.
Greetings from Portugal from a recent fellow enthusiast! Great video, bought a Multisumma 20 in what looked a great shape, but many parts were not working... following your general directions in this video I've managed to put it ALMOST in fully working condition! The only problem I'm having now, that renders the machine useless: both in addition and multiplication the machine does not carry decimal increments from the previous number operation. Example: ADDITION 12+13=25 (OK) BUT 12+19=21 (does not carry the 1 from previous position into the next ) ----- 24*2=48 (OK) BUT 28*3=64 (SAME, does not carry the 2 from previous position into the next ). Many parts were seized up... Do you have any clue of the offending part? All the best and thanks for sharing your knowledge on these amazing beasts.
Hi David, I'm away from my Multisumma for a few days, but I'll think about your problem and if necessary take a look at my machine when I'm reunited with it next week, then I'll get back in touch. In the meantime, could you add the fairly normal 123 + 456 + 789 + 987 + 654 + 321 - do it several times and make a note of the result each time - it might give me a bit of an idea, or it might not help at all - my hunch is that you'll get fairly random results but I could be wrong and you end up with the same every time.
@@GrumpyTim Thank you very much for your answer! I will turn it on and see what the machine spirit feels like answering - and post it here!
I had another little thought, try the same thing but add 3 zeros, ie 123000 + 456000 and so on - that way, if it's only the third column that's not carrying correctly, you might get the correct result, or it might be even worse. You could even try with 4 zeros, after that we should have more of an idea whether it's one column or the entire register that's playing up.
@@GrumpyTim Thank you for your generous help! Will try it tomorrow and let you know - I managed to find 2 service manuals online, one in English, the other in Italian, very detailed for problem solving and practical work to solve them... but if I have to make an open heart surgery to the Multisumma register or accumulator I fear the worst... will try it nonetheless and learn something in the process, even if so much above my present skill level!
@@GrumpyTim Greetings again! Finished the test, and again got a consistent same result every time: BLANK total! Good Lord, not even zeros... I'm totally baffled! Even not being able to carry it should had gave me some zeros: if I summ 950+50, for example, I am given an infamous 900 as a result! Thank you for all your patience with an internet stranger in mechanical distress!