You have a part and a prototype. SpecBuildr asks a short set of plain-English questions and turns your answers into a complete injection-molding specification a molder can quote and tool — draft, walls, gating and all.
Moving from a 3D print to injection molding is where first-timers get burned. The geometry that printed fine can be un-moldable — and a tool costs thousands before you find out.
Send a molder a raw STEP file and you'll get a list of DFM questions: wall thickness, draft, gate location, tolerances, ejection. SpecBuildr asks those first, in plain language, and flags the classic traps — thick walls that sink, undercuts that need side-actions, hinges in the wrong resin — so the spec you send is one a shop can quote with confidence.
A moldable spec comes down to six things. Here's what each means in plain terms — the interview draws them out of the part you already have.
What the part is, and how many you need per year.
In plain terms: one-off vs. a million changes everything about the tool.
The resin family and how much it shrinks as it cools.
In plain terms: what it's made of, and how much it moves.
How thick the walls are and the taper that lets it eject.
In plain terms: the two things that most decide if it molds cleanly.
Ribs, bosses, snaps, hinges, threads — and anything that traps the tool.
In plain terms: the bits that add tooling cost if you're not careful.
How tight the critical dimensions are and how the surface should look.
In plain terms: how fussy it is, and whether it has to look good.
How it joins the rest of the product and where it lives.
In plain terms: heat, chemicals, load — and what it mates to.
You describe the part, the quantity, and how it's used; the tool converts that into the parameters a molder needs — material and shrinkage, wall thickness and draft, features, tolerances, gating, and cosmetics — and warns you about the moldability traps first-timers hit.
A complete, downloadable molding specification: part and program, material, geometry and DFM notes (walls, draft, gating, cavitation), tolerances, assembly, and environment — formatted so a molder can quote and tool it.
It's generated from your answers and reviewed for major physics and manufacturability violations — it flags thin or thick walls, undercuts, and tolerance calls that fight the process. Treat it as a strong, quote-ready starting point, not a substitute for the molder's final DFM review.
The tool is free to use and needs no account. You keep the spec.
Five minutes of plain questions. A tool-ready specification at the end.
Start your molded part spec →