I'm mid-build, hopeing to get out at some point this season all being well... got a question on seating. I've noticed that some of the drivers run with a self made foam type seat whilst others use a GRP/fiberglass seat.

What are the differences in terms of safety & comfort?

I guess the self-made ones are cheaper, but do they offer the same support especially in an accident?

Any recommendations of comfy but affordable GRP seats?

Cheers,
Rob.

why bother nilram38 didn't even fit a seat, but used the chassis frame itself!

very clever
Rescued attachment 2frontside.jpg

Expanded foam in a bin-bag type seats are very comfy and offer excellent grip on your body but only if your dimensions stay the same (so doing driving in insulated trousers might be a problem if you made the seat wearing your speedos (which would be a problem anyway as some foam always oozes out and sticks itself on... not good)....
So for racing they're great. For day to day normal use a GRP seat's better though IMHO....

I helped my bro make a foam seat for one of his many cars... see
carbon seat blingage

hi as said the best way to get a seat to work properly is to do a 2 part expanding foam job.

None of the grp/carbon ones will work as well at holding you inplace but look better.

As a rough guide you should be able to do one for £60.

And yes you will hear all the horror stories of foam filling the garage to the rafters ect. But done with some common sense and patience they are quirte easy to do.

cheers matt

You just need to make sure the bin-bags are cut and shut well so that none can ooze out under pressure....

or...

assume it is going to ooze out everywhere and wear one of those biohazard disposable suits over the racing suit.... Otherwise you might end up replacing the racing suit. If you don't wear the racing suit the fit won't be that good and the escaping foam will no doubt find bare skin to attach itself on to.... . A painful (although cheap) alternative to the sack, crack and back wax though!!!

BenB

I've just read some of the site, and especially the carbon seat one - I would love to know how much that venture cost you in materials? It's something I'd like to have a go at some time in the quite distant future!

cheers,
Steve

quote:

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Originally posted by BenB
Expanded foam in a bin-bag type seats are very comfy and offer excellent grip on your body but only if your dimensions stay the same (so doing driving in insulated trousers might be a problem if you made the seat wearing your speedos (which would be a problem anyway as some foam always oozes out and sticks itself on... not good)....
So for racing they're great. For day to day normal use a GRP seat's better though IMHO....

I helped my bro make a foam seat for one of his many cars... see
carbon seat blingage

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Is Kirkey an option for a 750MC racer?

Does anyone have any experiences?

Hi tim there are a few people using the mega lightweight kirkey seats.

But to be honnest by the time you have got it bolted in and bracketed into a position to suit yourself it aint no longer a lightweght seat. and is still not moulded around your body to give the best comfort and support whilst driving around corners at 3.5 g .

cheers matt

There is a good article on making expanding foam seats here:
http://www.sjmmarsh.f2s.com/Caterham/Foam%20Seat.html

I don't think you actually need the seat base he uses, but it probably makes a neater job of it.

Thanks for all those responses, esp. the links to the articles, great help - think I will have a go at making a foam seat this weekend then...

How many cans am I likely to need to make a full seat (ie. base & back)? Will the 2kg pack (ie. 1kg of each part) from CFS be enough, or will I need the 5kg pack?

Cheers,
Rob.

Lots of useful information over on blatchat, it's a popular mod over there.

http://www.blatchat.com/T.asp?id=124677

and of course the effects of using too much in their classic canoe post

http://www.blatchat.com/T.asp?id=2911

I found that a 2Kg pack was not quite enough.

I ran a 2 pack foam seat for my first 2 seasons. It was quite comfortable (eventually - needed a bit of trimming after a broken rib). However as I was sitting on the metal floor of the car, I was very low. Too low in fact, as I could not see the near side front wheel, nor the front of the car. As a result, I could not place the car on the track as accurately as I would have wished (especially with other cars close by, as they "tend" to be in Locost racing).
So in 2005 I bought a GRP seat and fitted it, which put me in a more upright position. Yes, I lost a little centre of gravity, but I gained in visibility. Funnily enough I won a race that year (might be unrelated, but it pleases my ego to include it :-) )
So, advice: if you use a 2 pack foam seat (which on balance I would recommend) then make sure you can see the front of the car and both front wheels. If that means putting in a 1 inch board on the floor first, then so be it.
Dickie

Ive done two expanding foam seats for my (roadgoing) 7.

Dead easy, think like pouring concrete!

I did a litre for the squab in a heavy duty bin bag and a litre for the backrest in another one. The backrest needed a topup afterwards with another cupfull after the first lot had gone off.

let it start to go off, then sit in it when it just takes your weight, and it will squash to shape and go off properly.

I shuttered the seat areas with thick card and sat in it in my workshop overalls.

The workshop overalls recommendation is a good one. I've heard of people just wearing t-shirts and being alarmed by how warm the mixture gets while it's fixing.