Classroom mode

Exercise sheets for your class, each student with their own data

Choose the topics, how many exercises and the level, paste your list of students, and print one sheet per student and the solution key with the working. Every answer in the key is what this site's own calculator returns for the data on that sheet. The list of students stays in this browser, and a short code brings the same sheets back next term.

Topics

Glass weightkg/m², single panes, laminated and double glazing Metal section weightArea and kg/m of bars, tubes and profiles Sheet metal flat lengthBend allowance, bend deduction and K factor Linear cuttingBars to buy, the cutting plan and the offcuts Timber volumem³ or board feet of a timber list, with waste and cost Edge bandingMetres of edge tape and rolls for a list of parts Panel cuttingSheets needed and the layout, with the grain Cabinet cut listEvery part of a bookcase or a cabinet from its outside sizes

The sheet

Exercises on each sheet

Level

Basic: one piece, the formula once. Intermediate: tubes and profiles, lists, quantities. Advanced: K factor from DIN 6935, other angles, grain, waste and cost.

Title on the sheet

Group or course

Timber volume in

Students

One per line: a name or a number

Kept in this browser only: never in the code, never sent anywhere. Leave it empty and the sheets are numbered.

Number of sheets when the list is empty

The code of this set

Code

Write it down with the list: the same code and the same list give the same sheets again, here or on any computer. Keep it from the students: with it, the key can be made again.

How the sheets are made

Each student's numbers come from a generator seeded with the code of the set and that student's line in the list. The same code and the same list give the same sheets on any computer, in English or in Spanish; change one name and only that sheet changes. Sizes are taken from sizes that exist in a workshop: catalogue tubes and bars, sheet thicknesses, panel sizes, lengths in 5 or 10 mm steps.

Where the answers come from

Not from this page. Each answer in the key is what the engine of the site's own calculator returns for the data printed on the sheet: glass weight, metal weight, bend allowance, the linear and panel cutting optimizers, board feet, edge banding and the cabinet designer. The working writes the formula with the numbers in it, line by line, so it can be followed in class. The constants are the calculators' own: glass 2500 kg/m³, PVB 1070 kg/m³, the metal densities of the weight calculator, the K factor of DIN 6935 as the bend calculator applies it.

Cutting has more than one right answer

A cutting plan is not unique. The cutting exercises are drawn so that the optimizer's number of bars or sheets equals the lower bound worked out in the key, so that number is the fewest possible; the key gives the optimizer's plan, and any plan with that many bars or sheets is just as right.

Printing

Each student's sheet starts on a new A4 page, and so does each student's page of the key, which begins with a grid of all the answers for marking. Four exercises usually fit on one page. Cutting exercises and cut lists take more room, so a sheet with several of them, or with more than four exercises, may run to two pages. The four characters at the top of every sheet match its page of the key.

What this page does not do

No online answers. Students work on paper; nothing is collected or marked here.
Only what the calculators cover. Every exercise is one a calculator on this site can solve; there are no exercises on topics it cannot.
Nothing leaves the browser. The list of students is saved in this browser only; clear it with Forget the list on a shared computer.