Most of the risk in sourcing an injection mold from China is not the steel. It is the gap between what your part drawing says and what actually molds well at volume. A design for manufacturability review, or DFM, closes that gap before any steel is cut. At TK Mold USA every quote includes a free DFM review, run by a US based engineer working directly with TK Group’s tooling team in China. Here is what that review actually checks.
Why a DFM review matters before you commit to tooling
An injection mold is a hard tool. Once the cavity is cut, changing a wall thickness or moving a gate can mean welding, re machining, or a new insert. A DFM review catches those issues while they are still lines on a screen, not steel in a press. For a buyer sourcing offshore, it also creates a shared record of intent, so the mold shop in China and the customer in the United States are working from the same understanding of the part.
What the DFM review checks
Wall thickness and uniformity
Thick and thin sections in the same part cool at different rates, which drives sink marks, warpage, and internal stress. The review flags nominal wall, thick to thin transitions, and areas that need coring out to keep the wall even.
Draft angles
Every face that runs in the direction the part ejects needs draft so the part releases cleanly. The review confirms draft on walls, ribs, and bosses, and calls out textured surfaces, which need more draft than smooth ones.
Ribs, bosses, and gussets
Ribs are checked against wall thickness to avoid sink on the show surface. Bosses are checked for base radius, connection to walls, and the hole depth needed for the fastener.
Gate type and location
Gate position controls how the part fills, where weld lines land, and what cosmetic marks appear. The review proposes a gate strategy that fills the part evenly and keeps witness marks off cosmetic faces.
Tolerances and datums
The review separates the few dimensions that are truly critical to function from the many that can hold a standard molding tolerance. Tightening every dimension raises tooling cost with no benefit, so this step protects your budget.
Undercuts and side actions
Features that block straight ejection need lifters or slides, which add cost and cavitation limits. The review identifies them early so the quote reflects the real tool, not a simplified one.
Material and shrink
Resin choice changes shrink, flow, and the achievable tolerance. The review confirms the material and grade so the cavity is cut to the correct shrink factor.
How TK runs the review
You send your part, either as a 3D model or a drawing. A US based engineer reviews it in your time zone, then works with the TK tooling team in China to confirm the moldability of every feature. You get back a written DFM summary with the flagged items, the recommended changes, and a line item quote. Nothing is sent to steel until you approve the plan.
What you get back
A DFM summary that names the specific features reviewed, the changes recommended, the proposed gate and ejection strategy, and a transparent quote. You approve T1 samples before any production, so the first parts you hold are proof the mold does what the review promised.
A China built mold with a US based DFM review in front of it gives you offshore pricing without the offshore guesswork. Send your part and get a real answer.