Tools for Drainage Work, and Why Every Cut End Gets Deburred

Above ground drainage is plastic, so the work is cutting, marking out and deburring rather than heat. The deburring is the part people skip, and it is the part that causes the leaks.

The tools

Multi-purpose saw

Cutting plastic waste pipe, guttering and downpipe. Fine teeth give a cleaner cut — a coarse wood saw tears plastic and leaves a ragged end that has to be filed back before it is any use.

Cutting square matters as much as cutting clean. A pipe cut at an angle will not sit properly in a socket, and on a solvent weld joint it leaves a gap the cement cannot fill.

Plumb line

Finding true vertical — setting a downpipe straight down a wall.

A weight on a string, and gravity does the rest. It is worth using rather than eyeing it, because a downpipe that is slightly out is obvious from the street for the next thirty years.

String line

Marking a straight line between two points — the fall of a gutter run from the high end to the outlet.

“Fall” is the trade word for a deliberate slope. A gutter is normally given one, and the string line is how you get an even, correct slope across ten metres rather than a series of guesses.

Deburring tool

Removing the burr from a cut pipe end, inside and out. The burr is the rough lip of material left behind by the saw.

File

Cleaning up a cut end and putting a slight chamfer on it. A chamfer is a small angled bevel around the outside edge, so the pipe enters a push fit socket without damaging the seal.

Screwdriver

Fixing brackets, clips and support.

Why deburring matters

This is the part of the lesson worth understanding properly, because two different problems come from the same rough edge.

Inside the pipe: blockages

An internal burr sticks into the bore of the pipe. Waste catches on it — hair, grease, fat, tissue — and what starts as a rough edge becomes a blockage. It will not block today; it blocks in two years, and somebody has to find out why.

Outside the pipe: leaks

On a push fit joint the pipe slides past a rubber seal. A sharp external burr can cut or roll the seal as the pipe goes in. A rolled seal does not sit flat, so it does not seal, and the joint weeps.

Worse, it weeps behind a bath panel or inside a boxing where nobody looks. That is why the rule is absolute: every cut end is deburred and chamfered before it is jointed. It takes about five seconds.

Safety requirements

• Correct use of tools — the right tool for the job, used as intended.
• Tools maintained in good condition — sharp blades, sound handles.
• Appropriate PPE — eye protection when cutting, gloves for sharp cut edges.

Drainage adds a hazard the rest of the course does not: possible contact with foul water. Foul water is waste water containing sewage, as opposed to surface water, which is rainwater. It carries bacteria, so:

• Wash your hands before eating, every time.
• Cover any cuts before you start.

This is not fussiness. Waterborne infections from drainage work are a genuine occupational risk and they are entirely avoidable.

Basic maintenance

• Replace blunt saw blades rather than forcing them. A forced blade wanders off square.
• Keep the deburring tool sharp. A blunt one drags the burr round rather than cutting it off.
• Clean plastic swarf and solvent cement off tools before it sets. Once solvent cement has cured on a tool it is not coming off.
• Store them dry.