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For the team members responsible for set, see Technical Director and Head Carpenter. For the tools available, see ADC workshop.

Set is essential to most productions. It can be minimalistic or ludicrously elaborate; every term a variety of sets appear around Cambridge, each very different to the next. This article will cover common elements and considerations of set; other articles cover the people and tools available to build them.


A number of suppliers stock wood; the ADC has an account with Ridgeons but you can also buy from Wickes if you prefer.

Canadian Lumber Standard timber. Generally 3" by 2" CLS is used: that's the nominal size in inches (actual size 63 × 38 mm). This is a stick of pine with rounded corners and planed to a smooth finish. It's versatile and easy to use, but not the highest-quality timber. It may arrive warped (distorted due to moisture). There isn't much you can do about this! 4" by 2" is also available but less commonly used.
A cheap and bendy man-made board, produced from wood fibres rather than recognizable slices of wood. Very effective for flat-building. One side is smooth and not very absorbent, while the other is textured and much more absorbent, so it will use much more paint.
Available in various thicknesses (commonly 3.2 mm, 5.5 mm, 9 mm, 12 mm, 18 mm). Plywood is generally stiffer than a fibre-based board of the same thickness. Normally only boards 18mm thick or thicker are sufficiently fireproof to be used in front of (or without) a safety curtain, but this should be discussed with your venue before purchasing materials.

Ordering from Ridgeons

The wood for a set is expensive, so rather than TDs paying for it personally, wood is ordered over the phone on the ADC's account. (If you haven't done this before, speak to management who will explain the current process.) Ordering materials by phone is a new experience for many people, so some tips:

  • Make sure you have a list of exactly what you want to buy written in front of you.
  • Speak clearly. Describe each item you want clearly and wait for confirmation that they have typed it in correctly before moving on. E.g. "I'd like 14 pieces of 4800mm long three by two CLS".
  • After you have finished your list, ask for the total price, inclusive of VAT and write it down. Ask for the quote to be emailed to you (but be aware they won't always be successful in sending it!)
  • Ask them to confirm the number and dimensions of what you ordered. This is important, it's no fun to think you've ordered CLS and plywood, then receive 4 × 2 and MDF board. In particular, there is a difference between 3" by 2" CLS and general 3" by 2": the latter tends to be bigger and more expensive, resulting in all your calculations needing to be redone.
  • If you aren't sure what you want, e.g. you want some large dowel but you're not sure how big, you can ask on the phone and the salesperson will often be able to work out what the most suitable item is. You should also look in the Ridgeons catalogue (check website) for all your options.
  • Prices given on the Ridgeons website are unlikely to correspond to prices given over the phone, as discounts and delivery charges apply.


A flat is a simple and effective set piece. It's generally constructed from 3mm board (plywood or hardboard) with a 38×63mm CLS facing, but this can vary to make it stronger, lighter, or cheaper.

Flats vary in size; the ADC has stock flats available at 8', 12', and 15'7". (These are made out of lighter wood than CLS but have lasted many years.)

Building your own flat is very simple; essentially you just screw CLS together into a rectangle (butt joints with 2 5×80 mm screws each) and staple on the facing. As the facing can be assumed to be square (all angles at 90°), the frame should be pushed into a shape that matches the facing—usually the frame won't be perfectly square without some help. If there's overhanging facing after this, it can be trimmed flush with a router, using a router bit that's able to follow the CLS beneath. Adding glue to all joints makes the flat much more durable.

Flats can come in a range of shapes and sizes. For very large flats (more than one sheet of facing), it's necessary to add an extra length of CLS along the join between the facings, which forces them to align.