Brunsviga 13RM renovation

[Geoff Poskitt]

As of a week ago I am the proud owner of a Brunsviga 13RM. I am a complete newbie and this is my first mechanical calculater bought with the intention of getting it in working order and learning how to use it. As received from ebay it was in quite acceptable cosmetic condition. However, it was more than a bit stiff in operation and after working the levers back an fro was able to get it "working" but unable to get even the most basic calculations correct. I googled and came across lots of information and recommendations but I was rather knocked back by some recommendations about completely dismantling down to individual parts for cleaning hardened oil deposits. There is no way that I have the skills to even start.
So my next step was to  remove the covers with the intention of giving it a bit of lubrication. Here I find lots of contrary tips. Is WD40 a help or hindrance. Is the whole thing to be dumped in kerosene/clock cleaner/decreaser or what?
With the covers off and works visible I looked in my garage at what oils/lubricants and cleaners I had, and out of WD40. 3in1, silicone spray and others I decided to try hedge trimmer spray which is a cleaner, resin solvent, and lubricant for hedge trimmers and chainsaws.
https://www.amazon.co.uk/STIHL-Solvent-Trimmer-Blades-Chainsaws/dp/B001PH8AXQ
One squirt at a time I worked the machine and got the setting levers moving more smoothly.
My test calculation was to add 12345678 ten times which at first gave the wrong result. A few more squirts and I got a repeatable result of 1234567890. 987654321 tens times also worked after a while as well as subtracting back to zero. It appears now to work.
So my questions are:
Am I fooling myself that I have got this working and it will seize up again by next week?

Has anyone else tried Hedge trimmer spray??
What test calculations should I be using to prove it is getting the correct results and  consistently?
What alternative procedure can I follow to do a simple clean and lubricate without completely dismantling.
Much appreciative of any hints and advice.

Best wishes,

Geoff Poskitt

[058pawel]

Read this: 

https://johnwolff.id.au/calculators/Tech/Overhaul/Overhaul.htm

Taking machine apart is the best solution, but using kerosene is second best solution.

Such machine works also without any grease, and it works good for ever.

[Geoff Poskitt]

Thank you for your reply. I had already read John Wolff's advice on overhauling advice and excellent and comprehensive though it is, as a complete newcomer I am not able to even think about dismantling down to individual components. I did start with this guide for opening the machine up 

https://public.beuth-hochschule.de/~hamann/brunsviga/brunsviga-13rm/indexa.html

but as soon as I took out the carriage-lock, it shifted too far left and jammed the whole machine, it was a good hour of cursing before I managed to giggle something to get it back and promptly refitted the carriage-lock. As mentioned in my initial post, working the mechanism with the oil spray has got it apparently working. All the calculations I have now tried give the correct results so I am going to call it a day and put the covers back on. Thanks again!

[alan-uk]

Hi,
I have around 40 old adding machines and have them all working (well apart from one which is proving difficult) and have never had to dismantled any of them.
90% of the time the problem will be old oil has turned to a treacle like substance and jammed things up, finding parts which are stiff and working them with lots of thin oil (I use sewing machine oil) usually works for me although it can take a long time (they often free up just as I am about to give up all hope).  I can often be amazing the transformation which occurs when you get a bit of oil in the right place.
See:   https://alanesq.github.io/main/calculators/

[Geoff Poskitt]

Thank you Alan,

Good to hear that oil and patience can work. And indeed my calculator is working very smoothly now. Were I to try to get another on going I would continue with my hedge trimmer oil. The ability to dissolve resin deposits on the blade from conifer hedges seemed to work nicely on hardened oil in my Brunsviga.