Another chalenge
 

I don't think there will be a winner on this one ... but let me try . :o .
This ethno device is not a weapon, but it surely has a martial look, with its 1,650 Kgs. and 46 cms. length ... and capable to drill a 7 cms. hole.
But for drilling what ? I was told this is a tool associated with well sweep making; like for drilling a hole in the pole, i don't know :shrug:
In any case the blacksmith has to be a rather skilled artisan, to make such an object to be effective.
Any ideas ?

Timber augers came in a lot of sizes. Post&beam framing, shipbuilding; two more possibilities for needing a hole that size.

Aside from the one spiral auger here, scroll down for the picture of boat building tools (on a smaller scale).
http://www.gutenberg.org/files/16277...mages/069s.jpg
http://www.gutenberg.org/files/16277...he_boatbuilder

Cheers

GC

Thank you so much for the links, Glen,
I knew these 'classic' augers; there are a couple wooden shipyards around.
What i didn't know was the term auger which, in return, i tell you how we call them in portuguese: trados. I dare say that those augers are not only used in boat building but also on a multipurpose basis, civil carpentry, cooperage, etc. ... still in use nowadays, although produced by specialized machinery.
What i find atypical in my example is that, instead of having that spiral screw continuity, only has one single hélix blade, so wide as 70 milimeters, as if the material it has to drill is rather soft and so easy to penetrate.
I would venture this is definitely a tool for a very specific job.
Surely a primitive tool, i would say from the 19th century.

The spoon type with a lead screw, as the one you show, was often used in large mortise and tenon work. The auger removing a lot of the pocket and then chisels to square the mortise. The T handle and other pointy blade next to that in the linked picture are of your type.

Smaller modern mortising drills have a twist drill within a square tube acting as a four sided chisel. Large scale post&beam work is still often done the old way with a spoon auger. With wooden boat building, the round pocket in the beam, with pegs holding the planks.

Cheers

GC

Alright, duly noted ... and much obliged.
One of these days i will have a look in next town Naval Construction Museum (3 miles distant), to check whether they have this type of tool.

Someone came around and finally the mistery is solved.
Let me try and explain ...
Imagine a sort of chain, praying rosary style, with its beads. Then consider breaking the rosary, introducing it in a tube, where the beads fit precisely its interior diameter. After that, you introduce the tube in a water container and start rotating the rosary in the sense that the beads go up the tube. The result will be that the water is transported to the top, in quantities retained inside the beads interval.
That is the principle of water pumping in which this auger is used; for drilling a hole through a pine trunk where the beads (cork plugs) elevate the water, tractioned by some crank & handle resource.
No wonder this pumping system is called rosario (rosary) or de contas (beads).

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