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Sprue Tree (Runner)

Everything in the box hangs off one of these. The sprue is the plastic frame that carries parts out of the injection mold — and knowing its four features (runner, letter tab, gate, nub) is knowing where to cut, what to sand, and how instructions name every piece.

Specimen · Sprue Tree (Runner)

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Runner

Runner · Ø4 mm channel

The thick rails that carried molten styrene to every part during molding. Never cut parts off by twisting the runner — that is how gates tear chunks out of parts.

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All parts

Sprue Tree (Runner): every part explained

01RunnerØ4 mm channel
The thick rails that carried molten styrene to every part during molding. Never cut parts off by twisting the runner — that is how gates tear chunks out of parts.
02Letter Tabrunner A–H
Each runner carries a molded letter; instructions call parts by letter-plus-number, so piece C-14 lives on runner C. Reading tabs first is the biggest speed-up in early building.
03Gate0.8–1.5 mm neck
The thin neck connecting a part to the runner — the only place your nippers should ever cut. First snip out here, proud of the part, to relieve stress before the flush cut.
Shop Tamiya Sharp Pointed Side Cutter →
04Partstyrene, keyed pegs
The actual piece, molded with pegs and sockets that only fit its true neighbors. Snap-fit engineering means the part — not glue — does the holding.
05Nubsand 400→800
The stub of gate left on a part after the first cut. Flush-cut it, then sand through rising grits until the mark disappears — that ladder is the fundamental skill of clean building.
Shop GodHand Kamiyasu Sanding Sticks Assortment →

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Sheet 09 · Bench Goods

Wear the nub, not the mecha

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