Gluing Fin Rails - V3 - Two-Part Adhesive + Super Glue¶

Goal¶

Attach rubber fin rails with a structural two-part adhesive, then seal micro-gaps by wicking super glue along the seam.

Type	Hours
Implementation	0.5 h
Waiting	12 h

Material	Quantity	Unit Cost	Line Cost
Rubber Fin Rails Consumable One pair of soft rubber rails sized for bifin blades	2 m (enough for four rails)	£6.00 per metre	£12.00
Plastic To Carbon Adhesive Consumable 25 ml of 3M DP420 mixed with nozzle	1 25 ml syringe	£8.25 per 25 ml syringe	£8.25
Super Glue Consumable Thin cyanoacrylate to wick into any tiny gaps after bonding	1 3-5 g tube	per 3-5 g tube — Inexpensive
Fold-back clips set Consumable 20 mm binder clips for clamping rails during cure	1 set	Inexpensive
Total			£20.25

Tool	Purpose
Gloves	Protect your hands from resin, adhesives, and carbon fibers
Sandpaper	Prepare and smooth surfaces for better adhesion and finish
Window cleaner	Degrease surfaces before bonding or sealing
Fine-tip applicator (optional)	Control super glue wicking along the rail seam

Safety
- Wear gloves and eye protection.
- Work in a ventilated space.
Surface preparation
- Lightly sand the blade edge (400 grit).
- Lightly sand inside the rail channel.
- Clean both with window cleaner and let dry.
Apply the two-part adhesive
- Mix/apply DP420 (or equivalent) into the rail channel.
- Press the rail onto the blade, ensuring full contact; look for uniform squeeze-out.
Clamp
- Clip along the length with fold-back clips to hold alignment while curing.
- Wipe away excess adhesive before it gels.
Wick super glue into gaps
- After initial positioning, run a thin bead of super glue along the seam where rail meets blade.
- Let it wick into any micro-gaps; avoid flooding the rail to prevent brittleness.
Cure
- Leave clamped for the full structural cure time of the two-part adhesive (≈12 hours).

Super glue is brittle on its own; structural strength still relies on the two-part adhesive.
Avoid excess super glue—clouding (blooming) can occur if overapplied.