UBUHANZI
UBWIZA N'UBUZIMA
UBUKORIKORI
UMUCO N'AMATEKA
IMYIDAGADURO
IBIDUKIKIJE
IBIRIBWA N'IBINYOBWA
UBWUBATSI BUSUBIRA INYUMA
UBUMENYI
SIPORO
IKORANABUHANGA
IBYAMBARWA

Forged Centre Punch, Hardened and Tempered
A centre punch marks the spot for a drill. It is forged from tool steel like a cold chisel: the point is tapered at a yellow heat and ground to an angle between 60° and 90°. Only the point is hardened: heat the end about 3 inches back, dip the point in water at about 70 °F (21 °C) while moving it, polish it, and let the heat left in the shank run down until the point turns brown or purple, about 500–525 °F (260–275 °C); then cool it completely. A good punch marks tool steel without its point going dull.
Hagati
1–2 hours
Amabwiriza
1
1
Forge the taper
Forge the taper
Heat the end of the tool steel bar to a yellow heat and forge a long taper to a blunt point; finish just above the hardening heat, never hammering it black.
Ibikoresho by'iyi ntambwe:
Inkoni ifite impande umunani y'icyuma cy'ibikoresho1 igiceIbikoresho bikenewe:
Uruganda rw'umucuzi
Ingoyi
Inyundo yo Gucura
Amakoro y'Umucuzi2
2
Cool and grind
Cool and grind
Let it cool slowly, then grind the point to an angle between 60° and 90°.
Ibikoresho bikenewe:
Ibuye ryo gutyaza ry'uruziga3
3
Harden the point
Harden the point
Reheat about 3 inches of the point end to the hardening heat, keeping the tip high in the fire. Dip the point into clean water at about 70 °F, moving it so no sharp line forms, then plunge briefly and lift out with heat left in the shank.
Ibikoresho bikenewe:
Uruganda rw'umucuzi
Indobo
Amakoro y'Umucuzi4
4
Temper
Temper
Polish the point quickly and watch the colours run down to it; when the point is brown or purple, cool the whole punch completely.
Ibikoresho bikenewe:
Umwenda wa emeri
Indobo5
5
Test
Test
Strike a mark in a piece of tool steel; the point should not dull.
Ibikoresho bikenewe:
Inyundo yo GucuraIbikoresho
1- Umwanya
Iki gishushanyo gikora
Blueprint zijyanye
Izi blueprint zisangira ubumenyi — uburyo, ibikoresho cyangwa amahame
CC0 Umurenge rusange
Iyi blueprint yasohowe munsi ya CC0. Ushobora gukoporora, guhindura, gukwirakwiza no gukoresha nta kwemererwa.
Shyigikira Umuremyi ugura ibicuruzwa binyuze muri Blueprint ye Komisiyo y'Umuremyi byashyizweho n'Abacuruzi, cyangwa kora verisiyo nshya y'iyi Blueprint ukayinjiza nk'isano muri Blueprint yawe kugira ngo musangire inyungu.


