Gents, I'm working on my headrests for my car, with two concerns:
1) keeping heads away from the roll hoop
2) providing enough room front to back when bare headed, or wearing a helmet.
The backer plate/support is about 3 1/2 inches behind the seat back.
Current thinking is to bond 2 inches of sfi 45 conforfoam to a thin plywood backer, and use a small screw in the center to attach it to the aluminum backer. I think that will offer good support and energy absorption when wearing a helmet.
When without a helmet, I'd like the padding to project closer to the head. thinking about unbolting the pad and slipping a layer of rigid foam insulation (extruded polystyrene) between the plywood and aluminum backers, then bolting all together again. Has the benefit of bringing the pad closer to the bare head, offering an addition layer of energy absorption, and keeping the head further from the roll hoop.
Down side is that the polystyrene is not supported around the edges, so it may fracture under a hard impact. May also encourage the plywood backer to fracture, since the foam underneath can deform locally.
Any thoughts/criticisms appreciated.
1) keeping heads away from the roll hoop
2) providing enough room front to back when bare headed, or wearing a helmet.
The backer plate/support is about 3 1/2 inches behind the seat back.
Current thinking is to bond 2 inches of sfi 45 conforfoam to a thin plywood backer, and use a small screw in the center to attach it to the aluminum backer. I think that will offer good support and energy absorption when wearing a helmet.
When without a helmet, I'd like the padding to project closer to the head. thinking about unbolting the pad and slipping a layer of rigid foam insulation (extruded polystyrene) between the plywood and aluminum backers, then bolting all together again. Has the benefit of bringing the pad closer to the bare head, offering an addition layer of energy absorption, and keeping the head further from the roll hoop.
Down side is that the polystyrene is not supported around the edges, so it may fracture under a hard impact. May also encourage the plywood backer to fracture, since the foam underneath can deform locally.
Any thoughts/criticisms appreciated.