MoldCalc Pro — Injection Mold Design & Costing

🔩 Clamp Tonnage Calculator

Step 2

📐

Part & Mold data from Mold Size tab
Enter part details in Tab 1 (Mold Size). Values below update automatically.

Part L

–

Part W

–

Part H

–

Cavities

–

Mold Base

–

Proj. Area

–

Material

📊 Tonnage Results

Output

⚡ Required Clamp Tonnage
–
Metric Tonnes

Part Weight (per part, estimated)

–

grams

Shot Weight (total per cycle)
–
grams — all cavities + runner

Machine Size Recommendation

⚙️

Best physical fit: – (based on tiebar, daylight & barrel)
Next options:

Machine	Clamp Ton	Tie Bar (W)	Max Mold H	Inj. Weight	Status

🔍 Part Analysis

Step 1

📐

Upload your 3D part file or 2D drawing to get started
3D: Auto-fills dimensions · Draft analysis · Undercut · Wall thickness
2D Drawing: AI extracts part info · dimensions · tolerances · surface finish · notes

📐 Upload 3D File — Auto-fill Dimensions & Volume

📂

Drag & drop 3D file

or tap to browse

STL · OBJ · 3MF · STEP · IGES · BREP | Offline — file never uploaded

✅ After upload: Part dimensions & volume auto-filled → Go to 📐 Mold Size tab to continue calculations.

🎨 3D Viewer & DFM Analysis

Analysis

📂

Upload a 3D file to view

drag to rotate · scroll to zoom

Press Esc or click ⛶ to exit fullscreen

Upload an STL file on the left to run DFM analysis

📐 Mold Base Inputs

Step 2

Part Dimensions

Part Length

mm

Part Width

mm

Part Height

mm

Number of Cavities

Cavity Arrangement

Insert Configuration

Part Volume & Weight

Part Volume (from CAD — optional)

cm³

If you have exact volume from CAD/SolidWorks, enter here. Otherwise calculated from dimensions + wall thickness.

Wall Thickness (for volume estimate)

mm

Used only when CAD volume not entered.

Mold Type

Sliders

Number of Sliders

Lifters

Number of Lifters

Insert Material

Core / Cavity Insert Steel

🔄 Part Orientation in Mold Base

📐

Single Cavity — Auto Orientation
Part Length is placed parallel to Mold Base Length automatically.

📏 Mold Base Results

Output

Insert Length
–
mm — per insert

Insert Width
–
mm — per insert

Mold Base Length
–
mm

Mold Base Width
–
mm

Mold Thickness
–
mm

Est. Total Steel Weight

–

kg (full mold)

Mold Volume

–

cm³

🔲 Insert & Cavity Design

Step 3

📐

Part & material data from Mold Size & Tonnage tabs
Change part dimensions in Tab 1, material in Tab 2. Values update automatically here.

Part L

–

Part W

–

Part H

–

Wall

–

Material

–

Insert Design Parameters

Steel Wall Around Insert (pocketing wall)

mm

Typical 20–35mm, add 10mm for deep ribs/cores

Insert Height Add (underside support)

mm

Additional steel below part for structural support

Draft Angle

External Draft Angle

°

Internal Draft Angle

°

📦 Insert Size Results

Output

Core Insert (Moving Half)

Insert Length

–

mm

Insert Width

–

mm

Insert Height
–
mm

Cavity Insert (Fixed Half)

Insert Length

–

mm

Insert Width

–

mm

Insert Height
–
mm

Insert Steel Weight (both halves, per cavity set)
–
kg

〰️ Runner & Gate Design

Step 4

📐

Part & material data auto-filled from Mold Size & Tonnage tabs
Part volume estimated from dimensions × wall factor. Runner distance from insert diagonal.

Part Vol (est.)

–

Cavities

–

Runner Dist

–

Material

–

Viscosity

–

Material

Plastic Material

Wall Thickness

Part Wall Thickness

mm

Gate height, runner diameter and gate width are all based on wall thickness

Part Volume

cm³

Enter exact volume from CAD/3D software — or leave blank to use estimated value from part dimensions

Runner System

Runner Type

Gate Style

📏 Runner & Gate Results

Output

Runner Diameter

–

mm

Runner Width (trap)

–

mm

Runner Depth

–

mm

Gate Width
–
mm

Gate Height
–
mm

Gate Length
–
mm

Sprue Diameter (small end)

–

mm

Sprue Diameter (large end)

–

mm

Sprue Length
–
mm (= mold thickness)

Sprue Taper

–

°/side

📚 Rules of Thumb

GATE LOCATION

Always place the gate at the thickest section of the part. This ensures the thick area packs out fully before the gate freezes, preventing sink marks and voids.

TUNNEL / SUBMARINE GATE DIAMETER

Gate diameter = ½ × wall thickness (0.5t to 0.75t). Minimum 0.8mm for most materials. Smaller gates give cleaner de-gating but increase shear stress — check against material's max shear rate.

GATE TOO SMALL

Causes: high shear stress → material degradation, excessive pressure loss → short shots, jetting, burn marks, and premature gate freeze before packing is complete → sink marks.

GATE TOO LARGE

Causes: long gate freeze time → longer cycle time, large gate vestige → secondary trimming needed, difficult de-gating, risk of backflow when screw retracts.

RUNNER DIAMETER

General rule: Runner ∅ ≥ Part wall thickness. Typical range 3–10mm. Keep runners as short as possible to minimise pressure drop and material waste. Balance multi-cavity runners so all gates fill simultaneously.

FLOW LENGTH RATIO

Flow length ÷ wall thickness should be ≤ 150 for unreinforced materials, ≤ 100 for glass-filled. Beyond this, filling pressure becomes too high. If exceeded — add gates, increase wall thickness, or switch to hot runner.

SPRUE DESIGN

Sprue small-end diameter: ≥ 3.5mm (never smaller than largest runner). Taper: 1°–3° per side for easy ejection. Length = mold thickness — keep as short as possible. Sprue puller pin essential for two-plate molds.

WELD LINE AVOIDANCE

Weld lines form where two flow fronts meet. They are weaker than the base material (10–40% strength reduction for GF materials). Place gates so weld lines land in non-critical or hidden areas. Add a vent at the weld line to prevent burn marks.

HOT RUNNER NOZZLE SELECTION

Open tip: suitable for crystalline materials (PP, PA, POM). Valve gate: best for amorphous materials (ABS, PC, PMMA) and cosmetic parts where zero gate vestige is required. Valve gate adds RM 4,000–8,000 per drop.

GATE VESTIGE & COSMETICS

Tunnel gate: auto-de-gates, vestige ≤ 0.5mm. Edge gate: requires manual trimming, vestige 0.5–1.5mm. Fan gate: very low vestige but wide mark. Hot tip: near-zero vestige. Valve gate: zero vestige. Choose gate type based on cosmetic requirements of the A-surface.

MATERIAL-SPECIFIC NOTES

Select a material above to see specific gate and runner recommendations.

❄️ Cooling System Design

Step 5

🌡️

Material temperatures auto-filled from Tonnage tab selection
Standard melt & ejection temperatures loaded per material. Adjust if using specific grades.

Material

–

Wall Thick

–

Part Vol (est.)

–

Melt Temp

–

Eject Temp

–

Cavities

–

Material

Plastic Material

Coolant Settings

Coolant Inlet Temperature

°C

Typically 15–25°C (chiller) or 30–40°C (tower)

Target Cycle Time

sec

Cooling Channel Diameter

Temperature Override (optional — leave blank to use material defaults)

Melt Temperature Override

°C

Ejection Temperature Override

°C

🌊 Cooling System Results

Output

Cooling Time
–
sec

Total Cycle Time Est.
–
sec

Channel Distance from Surface

–

mm

Channel Pitch

–

mm

Heat to Remove

–

kJ/shot

Coolant Flow Rate

–

L/min

🔩 Cooling Circuit Layout

Circuits per Insert (Core)

–

cooling lines

Circuits per Insert (Cavity)

–

cooling lines

Total Circuits (all inserts)

–

lines to drill

Recommended Channel Ø

–

mm

💰 Mold Cost Estimator

Step 6

Currency & Steel Grade

Currency

Mold Construction Method

Insert type: separate inserts dropped into plates — better repairability, higher precision, suitable for long runs.

Insert Steel Grade

Separate insert steel cost added on top of mold base plate cost

📐

Mold dimensions auto-filled from Mold Size tab
Go to Tab 1 to change part details. All values update automatically.

Mold L

–

Mold W

–

Mold T

–

Part L×W×H

–

Cavities

–

Sliders

–

Additional Components

Number of Sliders

Number of Lifters

Part Geometry Complexity

Geometry Complexity

Affects machining time and EDM cost. Simple: no add | Medium: +RM 3k | Complex: +RM 8k | Very Complex: +RM 15k

Mold Life & Tolerance

Mold Life Requirement

Higher life → harder steel → higher material + machining cost

Tolerance Requirement

Tight tolerance → precision machining + extra QC cost

Design & Engineering Costs

DFM Analysis

Mold Flow Analysis

Mold Design (2D/3D)

Mold Trial & Validation

Secondary Processes

Texturing / Grain

Mirror Polishing

Surface Coating / PVD

Nitriding / Heat Treatment

📊 Cost Breakdown

Output

💰 GRAND TOTAL MOLD COST
–
MYR

📋 Cost Breakdown Detail

🔩 Material Costs
Mold Base Plates (C45 structural steel)	–
Insert Steel (core + cavity)	–
Total Material Cost (steel)	–
⚙️ Machining Costs
Mold Base (Supplier — LKM/Standard)	–
Cavity / Core Machining	–
Slider(s)	–
Lifter(s)	–
Hot Runner System	–
Geometry Complexity	–
Mold Life / Hard Steel Premium	–
Tight Tolerance Premium	–
Tooling Subtotal	–
📐 Design & Engineering
Design & Engineering	–
🎨 Secondary Processes
Secondary Processes	–
GRAND TOTAL	–
Cost per Cavity	–

Currency: MYR | Malaysian Ringgit (MYR)

🧩 Part Production Cost

Step 7

🔗

Mold cost, cavities & cycle time auto-filled from previous tabs
Mold cost from Costing tab · Cavities from Mold Size · Cycle time from Cooling tab

Mold Cost

–

Cavities

–

Cycle Time

–

Part Wt (est.)

–

Runner Wt

–

Material

–

Material

Material Price (override)

$/kg

Auto-set from material selection

Production Parameters

Scrap / Regrind Rate

%

Regrind Value Factor

%

% of price recovered from regrind

Machine & Labour

Machine Hourly Rate

$/hr

Labor Rate

$/hr

Overhead Rate

$/hr

Operators per Machine

0.5 = one operator per 2 machines

Mold Amortization

Target Production Volume

parts

Target Margin / Profit

%

📊 Part Cost Results

Output

Cost per Part
–
USD

Selling Price (with margin)
–
USD

Material Cost/Part

–

USD

Machine Cost/Part

–

USD

Mold Amort./Part

–

USD

Parts per Hour

–

pcs/hr

Revenue at Target Volume

–

USD

Cost Breakdown

Break-Even Analysis

Volume	Cost/Part	Mold Payoff

📋 Full Project Summary

📁 Project Information

Part Name

Part Number

Customer / Project

Prepared By

Revision

Date

Notes / Remarks

Part Image (optional)

No image selected

ℹ️

Fill in project details above · Complete all tabs · Use 📊 Mold Break-Up Sheet for full cost report · Use 📷 Capture in Part Analysis for 3D view

Mold Base (C45) — structural plates	–	kg	–
A+B Plates / Inserts (P20)	–	kg	–
Sliders (P20)	–	kg	–
Total Material Cost (steel only)	–	kg	–

Fill (injection)	–	sec
Pack + Hold	–	sec
Cooling	–	sec
Open + Eject + Close	–	sec
Total	–	sec