Making a fibreglass helmet can be quite easy. Fibreglass is a cheap, strong and durable material that is easy to mould and set in place. Making a helmet out of fibreglass would be a cheaper, stronger and thus safer alternative to buying a common plastic hard hat. Using materials commonly found at a home building centre, you too can make your own fibreglass helmet.
Coat the outside surfaces of a plastic helmet with white grease to allow the helmet to be easily removed from a fibreglass mould.
Coat some small sheets of fibreglass cloth with fibreglass resin and carefully apply them to the greased surface of the plastic helmet, taking care to cover all outside surfaces evenly with layers of resin soaked fibreglass cloth. Repeat this step until there are about four layers of fibreglass cloth on the helmet.
Wait two to three hours for the resin to cure and harden, after it is hard and dry to the touch, carefully remove the helmet from the fibreglass mould. Now you have an exact copy of the outside of the plastic helmet.
Coat the inside of the fibreglass helmet mould with white grease.
Cover some sheets of fibreglass mat cloth with resin and begin applying them to the inside of the mould, these sheets will become the structure of the helmet, so make sure to apply them evenly to create a strong helmet.
Wait two to three hours before carefully removing the helmet from the greased mould.
Sand the inside and outside of the helmet to create smooth surfaces. If you wish you may also paint the helmet with your desired colour.
Attach a hard hat insert to the inside of the helmet so the helmet is a snug fit for your head. Mark mounting holes on the inside of the helmet after determining the most comfortable orientation for the insert.
Drill the marked holes and mount the insert to the inside of the helmet using some nuts and bolts, adjust the head strap accordingly and wear as needed.
Any homemade helmet will not be safety certified, if you are required to have a certified helmet, this will not be a suitable replacement.