Tapered, straight and heavy rolling pins are three different tools

There is a short answer about rolling pins and a useful one, and they are not the same. What follows is the useful one.

The tapered French pin

A pin that narrows towards each end lets you pivot as you roll, applying pressure to one part of the dough at a time. That makes it easy to steer a sheet into a round, since you can push harder wherever the dough is thickest. It gives more feedback through the hands, because there is no handle isolating you from the dough.

The trade is that even pressure across a wide sheet takes more skill than with a straight pin. For pastry rounds and small quantities it is the more controllable of the two designs.

The straight pin with handles

A cylinder rolling on an axle applies the same pressure across its whole width, which suits rectangular sheets. Handles let you push with your arms rather than your hands, which is useful for stiff doughs. The axle also isolates you from the dough, so you feel less of what is happening under the pin.

For laminated work, where an even rectangle is the whole point, that consistency is an advantage. Cheap versions with loose axles wobble and produce uneven sheets, which is where the design fails.

Why weight matters

A heavy pin compresses dough with its own mass, so less downward force is needed from you. That reduces the tendency to press harder on one side than the other, which is the usual cause of a wedge-shaped sheet. It suits stiff, cold doughs that resist the pin, particularly laminated blocks straight from the fridge.

In the tin, a very heavy pin is unwieldy for delicate work and can compress a soft dough more than intended. Most bakers end up wanting a heavy pin for pastry and something lighter for everything else.

Materials and what they change

Wood holds a small amount of flour in its grain, which reduces sticking and is why it remains the default. Marble and steel stay cold, which is a genuine advantage in a warm kitchen working with butter. Some cold materials can be chilled before use, buying extra minutes before the fat softens.

In the tin, silicone and plastic surfaces release dough well but give you little weight to work with and much less feedback through the hands.

None of these matter as much as whether the pin is straight and whether the dough was cold.

Rolling to an even thickness

Guide rings or strips placed either side of the dough stop the pin descending past a set thickness. That removes the most common fault in home pastry, which is a sheet thicker in the middle than at the edges.

At oven temperature, two lengths of wood or two rulers do the same job for nothing, laid on the bench either side of the sheet. Rotating the dough a quarter turn between passes distributes any unevenness in your technique. Rolling from the centre outwards rather than back and forth over the whole sheet gives a more even result.

Domestic ovens routinely run twenty degrees off their dial, so trust a thermometer over the setting.

Improvising and when it is fine

A straight-sided bottle works adequately for a small quantity of pastry and has been used for generations. The main losses are weight and length, which matter for laminated work and barely at all for a tart base.

At oven temperature, anything with a seam or a ridge will print itself into the dough, so choose a smooth surface. For a dough that will be pressed into a tin rather than rolled, no pin is needed at all. Buy the pin when the type of baking you do starts asking for something the improvisation cannot give.

The takeaway

Pick the pin for the shape you are rolling, and let its weight rather than your shoulders do the pressing.

Temperature and time are the same argument held at opposite ends.