Calcusaurus : breathing life back into mechanical calculators

What is Calcusaurus ?

Calcusaurus is a company grown from a hobby that has gotten slightly out of hand - with collecting mechanical calculating machines also came maintenance, cleaning, repair, and restoration. After doing this for my own pleasure for decades, and gaining enough experience to fix almost anything, I started receiving requests to not just do this for my own machines, but to also help out in situations where the conservation and restoration capacity in e.g. a museum is insufficient, and a particular machine would be on the clean-and-repair list for several years before it could be made functional again. The market for Calcusaurus' services is miniscule, but real. So here we are, and you are looking at my webpage right now wondering about it for some reason, aren't you ?


What can I do for you ?

Calcusaurus has a comprehensive workshop for calculating machine repair, as well as an extensive reference library and a small stock of parts and parts machines.


If you have a mechanical calculating machine that is no longer functional and would like to see it working again, for sentimental or other reasons, I can probably help you out. This includes cleaning, oiling, adjustment, repainting and machining new parts if necessary.

Just as importantly - what I cannot do. The time I spend on Calcusaurus, doing work for others, is very limited, so expect a turn-around time that is measured with a calendar rather than a clock. I am not so experienced with two-function adding machines, and very highly automated machines from the 50s and 60s are often an enormous challenge anyway, due to their complexity and the changed manufacturing methods that tend to disencourage taking things apart. I do not guarantee success with either of these, but if you insist I try, then I'm afraid that a large part of the price you will be paying will be for the benefit my own learning curve. I definitely don't touch electronic calculators, and if you have an enormous electromechanical bookkeeping machine that you would like to get running, then I'm probably not your man either.

My philosophy regarding restoration is very simple: originality first. I will try to restore a machine with the utmost respect for whatever original materials and parts are still present. Obviously, machines need to be cleaned and lubricated where needed, and corrosion needs to be stopped and mitigated where it is present. I will try and conserve original paintwork and decals as well as possible, although of course I am also equipped for a full repaint if necessary. Generally though, my restorations are meant to conserve and restore functionality, not to make a machine brand spanking new, and erase all traces of its past in the process.

For my restorations I use good quality acid free lubricants (light machine oils, graphite, and the WD40 range of teflon containing oils and dry lubricants), abrasive metal polish (Peek metal polish), residue free cleaners and solvents (acetone, white spirits, carburetor cleaner, and WD40 cleaner), and museum quality finishing products (Renaissance wax).

Who am I ?

My name is Cris Vande Velde. Located in Belgium, and a crystallographer by education, I have been collecting mechanical calculating machines since 2002. I currently have a collection of over 250 mainly non-electric four-function calculators, many of which are rare and interesting. Head on over to the website hosting the overview of my collection! I enjoy tinkering with old machinery, and in the evening I can often be found in my workshop with a newly acquired machine from the collection that needs repair or adjustment.


How do you contact Calcusaurus ?

Nothing in the world could be simpler - just shoot me an email with this contact form, and I will get back to you as soon as possible.

So - how much would it cost to repair my calculator ?

Unsurprisingly, that depends. I charge a flat net fee of 35 €/h. Repair can be as simple as a wipe and a clean, some lubrication, and unblocking a safety that stopped a machine dead in its tracks. It can also be as complicated as taking a machine apart until the last screw, remaking several parts, and doing a complete repaint, which can take well over 100 hours. For an example of this, see my Brunsviga H, or the Britannic Duo. If you bring me your machine, I will do an evaluation of what is needed and how long it will probably take me, and come back to you with a quotation. This can even be done by appointment on a while-you-wait basis - the workshop is located near the Dutch border north of Antwerp. If I manage to repair your machine during the evaluation, I will just charge you 35€ for the first hour.



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