Make gaskets and seals first, then hoses and tubing, then tires. Without sealing rubber, hydraulic and pneumatic systems leak, engines do not run and pumps do not prime, so seals unlock the most other machinery per kilogram of rubber. Flat gaskets are cut from vulcanised sheet 1-3 mm thick and O-rings come in cross-sections of 2, 3 and 5 mm, so a small stock of sheet and a few moulds covers most early needs.
Part of Rubber Processing
A priority order for the first products a village makes from its rubber supply.
Seals Come First Because Machines Stop Without Them
The carrier says that without rubber hydraulic systems do not seal, engines do not run and vehicles do not roll. Each of those needs a different product, and each product asks more of the rubber supply and the workshop than the one before it.
| Order | Product | Why | Article |
|---|---|---|---|
| 1 | Flat gaskets, O-rings, cup seals | Smallest rubber use, most machines unlocked | Gaskets and Seals |
| 2 | Hoses and tubing | Flexible fluid connections | Hoses and Tubing |
| 3 | Tires | Large rubber use and hard to make well | Tire Basics |
| Also | Waterproofing, vibration mounts, medical gloves and tubing | Specific needs | Dip Molding (Latex) |
The corpus’s Rubber Products article covers pressed sheet, belts and rubber cement; this tree adds the detailed methods.
What You Need
- Cured rubber sheet of 1-3 mm for gaskets, and a sharp punch or knife.
- Moulds for O-rings; see Compression Molding.
- A tested compound: every product should come from a batch that passed Quality Testing, the rubber article of that name.
- Material: fresh rubber, or reclaimed rubber for the non-critical items; see Reclaimed Rubber.
Method: Deciding What To Make
Step 1: List what leaks or rubs. Which machines are stopped for lack of a seal or hose?
Step 2: Make a stock of O-rings. The carrier lists cross-sections of 2, 3 and 5 mm; make a range of inner diameters to have on hand.
Step 3: Cut gaskets from sheet to fit flanges.
Step 4: Make hose for the fluid lines that need flexibility.
Step 5: Leave tires for last, once sealing and plumbing are covered.
Common Mistakes
- Starting with tires. They use a lot of rubber and are hard to make reliable.
- Using natural rubber for oil seals. The corpus’s quality-testing article warns natural rubber swells in oils and dissolves in many solvents.
- Skipping testing, since a leaking seal wastes the labour of the machine it belongs to.
Safety
Hot cures and solvent cement
Curing needs a 140-160 °C bath or press, and the hot oil and hot mould hazards in Curing Temperature and Time apply. Rubber cement is rubber dissolved in turpentine, whose vapour is flammable; see the solvent warning in Hoses and Tubing.
What’s Next
- Learn next: Gaskets and Seals — the first products
- Combine with: Reclaimed Rubber — salvage as a feed for them