The Science of a Joint: Materials

by Sage Vasquez September 26, 2021

Smoking a joint is perhaps the most recognizable way to enjoy cannabis. Joints are extremely convenient: easy to smoke, easy to pass, and easy to transport. Rolling a joint isn’t difficult in theory either, but rolling a perfect one takes both practice and skill.

Armchair experts have long debated the science behind what makes a perfect joint; there are the crutch theorists, packing and density experts, to those who have strong opinions on grind size. Out of all these long-debated theories, which, if any, are correct?

Find out how RollPros engineers have produced the perfect joint—and it’s automated.

To help solve this age-old question, let's first consider how a joint is constructed. Joints are made up of the following parts:

1. Rolling/Wrapping Paper

The rolling or wrapping paper holds the cannabis flower together and gives the joint its shape. The paper acts as a form to direct the smoke and air from the burn tip to the mouth.

Papers are made from materials like hemp, flax, rice straw, or wood pulp and are typically somewhere between 2.75 (69mm)–4.33 (110mm) inches long. The size, length, thickness, and type of glue (used on the paper) all affect how the joint burns.

2. The Crutch
A joint’s crutch (also called the filter, tip, or mouthpiece), keeps unwanted ash or particulates out of the mouth, provides structural rigidity to the joint, and reduces cannabis waste by allowing users to smoke a joint to its end without burning their fingers or mouth while having a cooling effect on the smoke as it passes through the crutch.

Crutches are commonly made at home with paper. Ceramic, glass, and terpene-infused corn husk crutches have become increasingly popular and are sold at various retailers.

3. Cannabis Flower

Cannabis flower is not only the active ingredient for the smoking vapor—its interlocking flower pieces support the structure of a joint and fuel its ember at the tip.

Cannabis flower is typically sold in bud form—the variety, quality, freshness, and grind size will ultimately affect how the joint burns as well.

The science of a perfect joint certainly starts with the materials going into it—however, armchair experts are probably on the right track when they claim density influences a joint’s performance as well. How? Check out the RollPros Problem Solved series, where we discuss the challenges to creating a perfect joint and how the Blackbird Rolling System has solved many of the quality issues facing commercial cannabis pre-roll producers.