I too tryed to make one but the onlyway (the top one) is to cast it in bronze.
Maybe the one with the bullets is easyer to make but you have to let it be made by a proffesional metalworker (in dutch "freezen")
hope to be some help.
Vale
AgrimensorLVCIVS FLAVIVS SINISTER
aka Jos Cremers
member of CORBVLO
ESTE NIX PAX CRISTE NIX
Although it is a very bad picture, the lower one in this pdf shows (according to the description along with the pdf) the backside of an original from the Museo Nazionale Ramano at Piazzi delle Terme, Rome.
To me it seems like they are riveted on the back with some kind of bell-cap (or bell-washer or whatever you like to call it )
________________________________________ Jvrjenivs Peregrinvs Magnvs / FEBRVARIVS
A.K.A. Jurjen Draaisma CORBVLO and Fectio ALA I BATAVORUM
Although it is a very bad picture, the lower one in this pdf shows (according to the description along with the pdf) the backside of an original from the Museo Nazionale Ramano at Piazzi delle Terme, Rome.
To me it seems like they are riveted on the back with some kind of bell-cap (or bell-washer or whatever you like to call it ) Anyway, a simple ring will do fine, it seems.
________________________________________ Jvrjenivs Peregrinvs Magnvs / FEBRVARIVS
A.K.A. Jurjen Draaisma CORBVLO and Fectio ALA I BATAVORUM
According to an older article on Bill Thayer's excellent website:
Quote:The type of Roman abacus which has survived is a small portable instrument with movable beads which could be slid up and down slots. This type, which has some resemblance to the Chinese suan-pan or Japanese soroban, is nowhere mentioned in Latin literature. The two surviving examples, in Rome and Paris, are both about 5 by 3 1/2 inches.
Hi Jef,
I was at the National Roman Museum in Palazzo Massimo about 2 months ago.
I saw the abacus (which is the picture Sutoris) and I remember that the size of the long side was about 10-12cm ... it was very small.
The side behind it was impossible to see but I think it's exactly the solution suggested by Jurjen :wink:
If you want to replicate with a simple sheet can drill with a press drill and finish with a round file.
This one is made from ivory measuring 13 by 8 cm. This seems to be nearly the standard size, the one shown in the previous post measures 121 by 78 mm.
The upper one from Mainz appears to have a back plate, the other one shown in the previous post with the loose beads is the second origal from Mainz. Looking at the rim, most originals look cast, I am sure Marco is not going to be able to resist doing one :grin:
So how was the counting done on one of these? I understand the modern Asian(or is in ancient?)method. Is this similar? I don't decipher the inscriptions, some of them. I'm just and unschooled 21st C Texan. Any pointers?