Why do resin parts need washing?

Resin parts are cast in silicone moulds coated with release agent. This oily residue prevents paint and glue from adhering properly. Soak parts in warm water with washing-up liquid for 15-30 minutes, then scrub gently with an old toothbrush.

What is pinning and why is it needed?

Pinning means drilling holes in mating surfaces and inserting short lengths of brass or steel rod to create a mechanical joint. Resin is heavier than plastic and CA glue alone may not hold. Pinning adds structural strength to the bond.

What diameter brass rod should I use for pinning?

For 1:48 and larger parts, use 0.8-1.0mm brass rod. For 1:72 and smaller, use 0.5-0.7mm. The rod should be about 4mm deep in each part. Use a pin vise with a matching drill bit to make the holes.

Can I use poly cement on resin parts?

No. Poly cement only works on styrene plastic — it dissolves the surface to create a weld. Resin is a different material and poly cement will not bond it. Always use CA (superglue) for resin. Medium viscosity CA is best for most resin joints.

Resin Parts Calculator — Free Plastic Kits Tool

How We Calculate This

Estimates the preparation time, CA glue and pinning materials needed for a batch of resin aftermarket parts, so you can plan a bench session and order materials before you start.

Formula

Wash time = your Wash Time input (default 15 min — a typical warm soapy-water soak)
Prep time = Parts × Time per part (≈3 / 6 / 10 / 15 min for small / medium / large / XL parts — flash removal, cleanup, test-fit)
CA glue = Parts × Glue per part (≈0.02 / 0.05 / 0.1 / 0.2 ml by size — roughly one medium drop per medium joint)
Pins needed = round(Parts × Pinning factor) (0.3 / 0.6 / 1.0 for some / most / all)
Brass rod = Pins × Pin Length (default 8 mm per pin — split ≈4 mm into each mating part)
Total time = Wash + Prep + (Pins × Pin Set Time) (default 5 min per pin to drill and set)

The per-part time and glue figures are rule-of-thumb planning estimates from typical bench experience, not measured constants — your own pace, part complexity and the CA viscosity you use will vary. Treat the totals as a guide for budgeting time and materials, then adjust the Advanced Options to match how you actually work.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before purchasing materials.

Resin Parts Calculator — Aftermarket Prep Planning