Seat reinforcement

[Tim V-W]

There seems to be a few Q's about seat installation lately, so apologies for yet another.

 

I have aquired a pair of Tillets and they will be replaceing Pre S seats. I have done a search and know that the existing seat runners use the chassis for support while the later seats bolt straight through the floor.

 

I have looked at the Caterham site as I discovered that some strengthening is recommended and found a pair of U channels.

 

Questions are:

 

The CC site seems to sell a pair but suggest that only one per seat is necessary, is that correct or am I reading it wrongly?

 

The brackets seem to be made from really quite thin material (ali or steel) and I was wondering if anyone had fabricated or sourced an alternative?

 

When fitted do these reinforcements go inside or outside the seat well?

 

Thanks

 

Tim

[Nic Day]

Hi Tim

 

you will need two u secstions per seat. I have them on my car as I found I was re riveting the floor every 6 months (fat ar$e that I am!!!)

 

Now with the u sections - I am only doing the drivers side every year or so. They do help but now mine are a little bit banana shaped!!!

 

I have been told the only way to really sort it out is to install the lowered floor section. But at over £250 this seems to expencive for me!!!

 

 

 

Rocket Communications - Events, Media, Video here

 

 

 

Edited by - Nic Day on 20 Nov 2007 15:09:20

[alan c]

Tim

Looks like we are both tackling the same problem. In my last car when I changed seats I just bolted through the floor but was never happy with that, it seemed so much weeker than the seat rails bolted to the chasis.

I have purchased the plates to reinforce the floor, each pack has a pair in them. They are aluminium sheet about 2mm thick, from memory. About 8cm wide with angles each side of about 5mm.

They are long enough to reach between the mounting points of your old seats so you can bolt to those (Under the floor) and then drill through floor and plate to mount the seat and then add the rivets later.

But the only predrilled holes are for rivets and for the seat rail and if you mount centrally through current fixing points they may not be far enough apart for the seat rails at least that appears possible for the S type seats I am installing.

I intend to offset them so they are wider apart and under the seat rails and then bolt/rivet through like that.

Thats the theory but I need to measure a few more times before I approach with a drill in hand!

Hope the above helps.

Alan

[Tim V-W]

Hi Alan

 

It was your thread that made me think about the reinforcement.

 

I was thinking that I might purchase about 3.00m of ali channel and simply bolt these up with the seat fixing bolts under the car. Rather than paying £60 ish for CC's ones.

 

I've not checked yet, but I assume that the existing (pre 96) seat bolts go right through the chassis and the floor rather than having rivnuts in the chassis member but that these holes are too far apart for the new seats.

 

My plan for fitting is as follows:

 

Sit seats in car and mark reference points on floor (having made sure that the drivers side adjusts fully forward as I'm short!)

 

Make a paper template of the position of the seat rails and bolt holes. Lay this in the car lined with reference marks and drill through floor.

 

Drop seats back in and insert bolts.

 

From below fit ali channel over bolt thread and then fit washers and nuts (either using cap heads and an allen key, or pussers mate (Jane) to hold spanner on bolt head.

 

Thoughts welcome from those that have already done this (or those that haven't)

 

Thanks

 

Tim

 

 

[alan c]

Tim

Here is where I have got to, it may be a bit different for you if you are fitting tillets and not S type seats.

Firstly the bolts holding the existing seats in do go right through the floor, at the front through a cross rail and at the back through a spur of the frame, a solid spacer and then the floor. Front ones are easy to remove, the rear ones need a 'mate' unless already fitted with cap head bolts.

With a seat out I have a front to back dimension between holes of 54.5 cm and width 28cm.

The seat rails on S types are at 32cm centres, width.

So I will fix the plates below the floor using the existing holes and but off centre so the plates are below the seat rails.

Then when I place the seats in and follow a similar procedure to your proposal I can mark up and then drill through the floor and the plate in the right place for the seats, if all goes well. Seat will then bolt in using cap head bolts.

S Type seats have a runner 33cm long and about 18.5cm of travel so spacing these correctly I can use the full movement.

As real overkill I will then drill all the rivet holes from below and insert the rivets from above so they sit more or less flush on the inside. If I was really keen I would use countersunk rivets but I dont think I need to.

Hope this ramble helps.

Alan

[Tim V-W]

Alan

 

As a real measure twice cut once sort of person - it helps!

 

Thanks

 

Tim

[alan c]

Tim,

Agreed, I measured several times before I drilled anything. The plates are now all drilled and with some minor adjustments they fit. I was going to reuse the existing bolts but the unthreaded portion is too long so I need some new bolts and the plates are in. Also just about marked out the seat positions as well, its made a bit easier as there is no room for any side to side movement.

If you can source aluminium and bend it you could probably make these plates for a lot less. It would be even neater to make something that went inside the car but thats beyond my skills

Alan

[IanJ]

I wasn't happy with the idea of using the floor plus channels to support the seats. I extended the seat rails to pick up on the chassis cross member just in front of the seats and added some additional support to the bulkhead behind the seats.

 

There are some photos here

 

 

Ian 😬 1.6K SS Superlight #006

Penn Sevens Here

 

Edited by - IanJ on 21 Nov 2007 09:14:38

[alan c]

Ian,

I am using the floor channels but first bolting them in situ to the chassis cross member in front of the seats and to the reinforced point at the rear where the old seats were bolted. Then I bolt the seats through the floor and finally rivet the channels to the floor as well.

All being well I will have them done before the weekend.

Alan

[IanJ]

Alan,

 

Your approach sounds like it will be the ultimate solution 😬 Unfortunately, I don't have the rear pickup points so my effort wasn't as effective. I Look forward to seeing your new and improved car at Penn (although I may not make it this month).

 

 

Ian 😬 1.6K SS Superlight #006

Penn Sevens Here

[alan c]

Ian

I will definately be at Penn this weekend but not sure I will get both new seats done in time so it could be in the tin top.

Alan

[RiF]

We do a carbon version 😬

All these U sections should be riveted with stainless rivets not ally ones into the chassis rails. Ally rivets are OK into the floor only part that the U rivets to.

 

RiF Driving one of the first Duratec 7, and building CA07BON for Henrietta 😬 😬 😬.for pictures of 7 and carbon andCA07BON

[alan c]

Richard

I have bolted mine to the chassis rails as on older cars there are already holes there and I will then add the rivets, just using ally rivets throught the chanel and floor.

Alan