Skip to content

Cast iron, bench-mounted, and a copper screw

KAKA INDUSTRIAL AC-100

The only clamp on this shelf that holds a right angle on its own, bolted to a bench — with a copper-plated screw so spatter does not weld to the thread.

KAKA Industrial cast iron 90 degree angle clamp holding two square tubes

KAKA INDUSTRIAL AC-100

The only clamp on this shelf that holds a right angle on its own, bolted to a bench — with a copper-plated screw so spatter does not weld to the thread.

Amazon reference
B0159ZUQ22
EAN
0745369240840
  • Holds a true 90 degrees mechanically, which is what this hub’s buying tip says magnets cannot do
  • Publishes all three jaw dimensions — 4 in opening, 2-1/4 in height, 3-1/2 in width
  • The listing calls 26 lb a "lightweight design" in the same sentence that publishes the figure

Best for: Repeating the same square corner, where the clamp sets the angle instead of a magnet suggesting it

≈ $155
Check price on Amazon

Specifications

Amazon reference
B0159ZUQ22
EAN
0745369240840

This hub opens on the fact that steel moves as it cools, and its buying tip says plainly that a magnetic square will not stop it: position, tack both ends, then clamp mechanically before running the bead. Until this shelf gained its American half, there was nothing here to clamp a corner with — five published products, of which three are magnets.

This is the mechanical answer. Cast iron, bolted through a slotted base to a bench, with a 4 in jaw opening, jaws 2-1/4 in high and 3-1/2 in wide, and a true 90-degree seat that holds two sections against each other while the weld shrinks. The two jaws take different sizes, so a tube into a plate or a thick section onto a thin one is still square.

Two details are worth naming. The screw is copper plated, because spatter does not stick to copper and a thread full of welded spatter is a clamp that will not open — a small thing that says the tool was designed for an arc. And the mass, which is published as 26 lb in the same sentence that calls the design “lightweight”. For a fixture that is the right way round: weight is what stops it moving. The word is still the maker’s.

Availability

Read on the day this page was built: $155 at the American Amazon shop.

Read from Keepa on the day this page was last revised; stock and price both move without notice.

Prices quoted in this text were read on 2026-10-07. The live price is at the top of the page.

The questions welders ask

Is it light or heavy?

Heavy, and the listing publishes the number while describing the opposite: "The lightweight design (net weight 26 lbs) and slotted bottom hole allow easy installation and workbench mounting." Twenty-six pounds is nearly twelve kilos. For an angle clamp that is a feature rather than a fault — mass is what stops a fixture moving as a weld shrinks — but it is not light, and the word is the maker’s.

Why a copper-plated screw?

Because molten spatter does not wet copper the way it wets steel. The screw on an angle clamp sits inches from the arc with its thread exposed, and a bead of spatter welded into a thread is a clamp you cannot open. Copper plating is the standard answer and it is the kind of detail that tells you the tool was designed for welding rather than adapted from woodworking — which the same listing also offers it for, alongside photo framing.

How is this different from a magnetic square?

It resists the weld. This hub’s buying tip is blunt about it: a magnetic square holds parts for tacking, cannot resist the pull of a cooling weld, and loses grip on hot steel. A cast iron angle clamp screwed down on a bench holds the angle while the bead is run and while it cools. The magnets on this shelf position; this holds.

More clamps & vices

  • Monster & Master V-pad locking pipe clamp on a square tube

    Monster & Master MM 10 in V-pad locking clamp

    A V-jaw clamp that publishes the tube sizes it holds and states plainly that it takes square section as well as round.

    Amazon reference
    B08LD3GBZS
    EAN
    6972748327999
    • Publishes the sizes it holds — 1, 2 and 3 in — rather than a single capacity range
    • States that the V-jaws take plain round AND square tube, including mixed joints
    • A 3 in ceiling, below the 6.3 in opening of the large clamps on this shelf

    Best for: Frames mixing round and square tube, where one clamp has to seat on both

    ≈ $40
    Check price on Amazon
  • Four POWERTEC Type-225D horizontal toggle clamps

    POWERTEC 20326, Type-225D toggle clamps, 4-pack

    Four quick-release clamps that publish what no other clamp in this hub publishes — a holding force, and every dimension needed to drill the mounting holes.

    Amazon reference
    B079SWJC4W
    EAN
    0843441100881
    • Publishes a holding capacity — 500 lb per clamp — which no other clamp in this hub does
    • Publishes every mounting dimension: base 1-3/8 by 1-1/2 in, slots 1/4 by 3/8 in spaced 7/8 by 7/8 in, bolt length 2-1/2 in including the rubber foot
    • A toggle clamp holds down, not sideways — it is a fixture component, not a hand clamp

    Best for: Building a jig or a fixture, where the clamp is screwed down once and used a thousand times

    ≈ $19
    Check price on Amazon
  • Sawyer Welder’s 3rd Hand pipe alignment clamp fitted to a pipe butt joint

    Sawyer Mfg Company Welder’s 3rd Hand pipe clamp

    A pipe alignment clamp whose five bullets contain no capacity, no weight, no dimension and no material grade — on the highest price in the American half of this hub.

    Amazon reference
    B07MKPLQR5
    EAN
    0602573288498
    • Built for the one joint nothing else on this shelf addresses — a pipe butt weld, where both halves must stay concentric
    • Portable, so it goes to the joint rather than the joint to a bench
    • No pipe diameter range published — the one figure that decides whether it fits anything you own

    Best for: Pipe butt welds, if you can establish from the seller which diameters it fits

    ≈ $185
    Check price on Amazon

Elsewhere in the workroom

  • DEWALT 4-1/2 inch cut-off wheels in a five-pack

    DEWALT DW8062, 4-1/2 in × .045 in, 5-pack

    A named-brand thin cutting wheel in the smallest pack on this shelf, claiming fifty per cent longer life against nothing in particular — and publishing no maximum speed.

    Amazon reference
    B005B8LZCI
    EAN
    0028877525877
    • A .045 in wheel, which is the thin-cutting standard rather than a compromise thickness
    • Two sheets of fiberglass reinforcement stated, which is what stops a thin wheel shattering
    • No maximum speed published anywhere — the first of the two markings this hub says matters

    Best for: A few cuts in steel, from a brand whose discs are on every builders’ merchant shelf

    ≈ $6
    Check price on Amazon
  • EZARC 1.5 inch rotary cut-off wheels in their storage case with mandrels

    EZARC 80921501, 1.5 in rotary, 30 discs and 2 mandrels

    The only disc listing in this hub to cite the European safety standard for bonded abrasives by number — alongside the highest published speed rating on the shelf.

    Amazon reference
    B0DNHSC1VW
    EAN
    0810151450681
    • Publishes a maximum speed of 45,000 rpm, the highest on this shelf and appropriate to a rotary tool
    • Cites EN 12413 by number — the European standard for bonded abrasive safety — and ASM07
    • The title says 32-pack and the storage bullet says 30 discs: the pack is 30 wheels plus 2 mandrels

    Best for: Cutting bolts and hardened fasteners with a rotary tool, where the speed rating has to be right

    ≈ $18
    Check price on Amazon
  • Kuenuilr 44-piece rotary cutting set with resin discs, saw blades and diamond wheels

    Kuenuilr d36, 44-piece rotary cutting set

    The only set on this shelf that mixes resin, high speed steel and diamond wheels — on a listing that says five blade diameters and then lists six.

    Amazon reference
    B07WDJ8Q79
    EAN
    0793610636218
    • Three different wheel technologies in one box — resin for metal, HSS for wood and soft metal, diamond for glass and stone
    • HSS blades in a range of diameters, from 22 to 50 mm (0.87 to 1.97 in)
    • Says "5 kinds of outer diameters" and then lists six: 22, 25, 32, 35, 44 and 50 mm (1.97 in)

    Best for: A rotary tool that has to cut metal, wood and glass without three separate purchases

    ≈ $10
    Check price on Amazon

All clamps & vices