OpenSling Assembly Overview

This is a high-level assembly guide for the current OpenSling reference distiller. It is inspired by the public Slingshot mechanism, but it is not presented as a factory clone or a certified potable-water product.

Reference Build Scope

The current reference build assumes:

• a low-pressure vapor-compression distillation loop
• aggressive heat recovery on feed, product, and blowdown streams
• a custom frame plus pressure-bearing wet hardware
• removable non-pressure custom parts for routing, guarding, mounting, and instrumentation

Before You Build

Do not start with contaminated water. First assemble and commission with clean water so that you can:

• pressure test the shell and fittings
• validate controls and shutdown logic
• characterize leaks and parasitic heat loss
• establish baseline pressure and temperature behavior

Builder Flow

If your goal is to actually get parts on a bench instead of just reading theory, use this order:

1. Read the Alpha Buy List and Missing Pieces.
2. Order the buy now parts first. Those are the lowest-regret purchases in the current repo state.
3. Print or machine the non-pressure parts in the Fabrication Pack.
4. Build the frame, drains, feed-side routing, and instrument mounts before buying the pressure core.
5. Hold the expensive geometry-dependent parts until the pressure shell, heater mount, and compressor operating point are frozen.
6. Hydrotest with water before any heated or dirty-water run.

The current OpenSling docs are honest about what is still missing. That is better than pretending a pressure vessel or heater package is already settled when it is not.

Assembly Sequence

1. Build the frame and mounting surfaces. Mount the wet section low and the controls section high. Leave service clearance around the compressor, heater, knock-out pot, and sample ports.

2. Assemble the feed, preheat, and blowdown loop. Install the feed tank, coarse strainer, preheater, blowdown needle valve, drain routing, and collection vessel before the distillation core goes in.

3. Assemble the evaporator/condenser core. Build the main pressure shell, internal tube bundle, service ports, relief provisions, and insulation interface. Pressure-bearing parts require hydrotest before thermal commissioning.

4. Install demister and mist protection upstream of compression. Add the knock-out/demister stage between the steam chest and the compressor so entrained droplets do not become compressor damage.

5. Mount the vapor-compression stage. Install the side-channel/regenerative blower or chosen compressor with isolation mounts, a short service loop, and temperature/pressure instrumentation on both sides.

6. Route the product condensation and recovery lines. Direct condensed product into clean-side tubing, then through any polishing or storage-protection steps you plan to test.

7. Install startup heat and controls. Add the startup heater, contactor or relay hardware, level sensing, pressure sensing, and emergency stop logic. Keep wet and electrical zones visually separated.

8. Fit custom support and routing parts. Install the printed guards, cable guides, hose separators, panel blanks, and mounting brackets from the Fabrication Pack only after major hardware alignment is fixed.

9. Hydrotest and leak-check. Test the pressure boundary with water, not steam, first. Record pressures, dwell times, and any gasket movement.

10. Commission with clean water, then move to dirty-water trials. Establish stable startup, steady-state compression, blowdown control, and product routing before exposing the machine to fouling loads.

Minimum Commissioning Data

• feed, shell, and compressor pressures
• steam-side and product-side temperatures
• startup time to stable production
• blowdown rate
• product conductivity or other basic quality screen
• treated volume before noticeable fouling or drift

Build Philosophy

The goal is not to hide complexity inside a sealed box. The goal is to create a machine that can be opened, sampled, cleaned, modified, and understood by the next builder.