How to play
- Drag a part from the pegboard onto the drain. A green ring means it can go there now; red means something has to go in first.
- Tap a washer on the board to flip it. Its taper has to point into the fitting.
- Tap a fitted slip nut to tighten it: hand-tight, then a quarter turn.
- Press Run water to test. Hint, Reset and Watch it built are under the figure.
What the puzzle teaches
- Slide the slip nut on before the washer: the washer sits at the pipe end, under the nut.
- At the wall trap adapter it is the other way round: washer into the hub, nut threaded on over it, then the arm slides through.
- A tapered slip-joint washer seals with its taper pointing into the fitting.
- Plastic slip nuts go hand-tight plus about a quarter turn; overtightening cracks them.
- Model plumbing codes call for a trap seal between 2″ and 4″ deep; this trap holds 3-5/8″.
- The trap arm falls about 1/4″ per foot toward the wall.
Parts on the list
- 1-1/2″ tailpiece (12″)
- 1-1/2″ J-bend
- 1-1/2″ trap arm
- Trap adapter at the wall stub
- 3 slip nuts
- 3 tapered slip-joint washers
A teaching model. Follow your local plumbing code and the maker's instructions.