Best way to remove material from my bead seat?

[AlanVDW]

I have a bead seat inset in my CFF that makes me sit too high in the cockpit. I pass the helmet to roll hoop test but I'm uncomfortable with the broomstick clearance. I'd like to lower my self in the car, so I'd need to trim the bottom area where my ass is. What's the best way to evenly carve out that convave area?

[BeerBudgetRacing]

IMO carving it will yield an unsatisfactory result.

Either use the old seat to determine new position and pour a new one.

Or just start over.

[Fred Michael]

A hot knife and a rasp for cutting and finishing but trying to get an existing seat lower is an exercise in futility. Make a new seat

[Rick Kirchner]

Well I'll be the contrarian here. I've used a die grinder with a flapper wheel on it to contour bead seats. Alternatively, cut the bottom of the seat off completely and put a layer of ensolite on the floor to keep your butt off the aluminum and provide a bit of padding. Just buy a military sleeping pad at a surplus store for the material.

Then contour the remaining seat back to blend in with the foam floor.

[EYERACE]

1. I'd use a hack saw blade held by one of those tools that extends about half the blade's length out in free space
or
2. I wouldn't do the modification at all......because on an impact that would jam your spine down, you'd care to have that material absorb energy......the alternative being compressed vertebrae that can lead to what is called burst fracture. Don't ask me how I know but I'm about one and a half inches shorter because of such. Maybe the story is still posted here somewhere at ApexSpeed from about 11 years ago. They told me I was lucky I can still walk. Thanks to Dr. Terry Trammell of OrthoIndy fame and the EPP seat (the seat was $3,000) made by BaldSpot MotorSports I'm back out on track.... but sitting about 3 inches higher now in the car than before. I don't like that I'm sitting 3 inches higher but without that much multi-impact material under me (a regular bead seat is only single impact material) no one with Medical understanding of the racing-with-injuries circumstances would dare go out again. There's still no guarantee that I'd be OK under repeat impact conditions....but then there wasn't any to begin with. The car's main hoop had to be altered and raised by 3 inches too.....between the hoop and how high I sit I've severely hampered my aero.

[HazelNut]

when i do seats I use a fish filleting knife a to trim them. works great. It's worth a try but re-contouring the topside is going to be difficult and you're probably not going to get a nice smooth surface. Maybe try a sanding ball?

https://www.harborfreight.com/4-in-8...all-61182.html

I tend to agree that you're probably going to end up making a new seat.

[Rick Kirchner]

I've really had no problem with flapper wheels. It is a bit more of a challenge to get a really "clean" surface with styrofoam because it has a tendency to melt a bit and hang on at the edges, but that can be brushed off.

Pour foam is easier to sand but what you have to go thorough to protect your eyes from the tiny sharp shards is something else!

[AlanVDW]

I am trying find the best fit before replacing with a new bead seat.