Thread: Plugger and The Camel

Great update....keep at it.

Originally Posted by Archangel007

Hi Gang,

I have spent a fair few hours this week playing catch-up with The Camel. As per the post last week, this week saw us turn our attention to the seat base and the work that needs to be done around this. Primarily the job of reinforcing the seat base because of two reasons:
1. The battery box and its surrounding structure that traditionally supports the seat base will no longer be there because this area is now taken up by the auxiliary fuel tank and,
2. The seats we are using in Camel are from a BMW 525i - they are nice leather buckets with a very low squab height. And of course, BMW mount all their seat belt anchorage points directly to the seats and not to the floor pan so the structure that mounts the seats also has to be able to cater for the loads on the anchorage points in case of a collision.

Now Camel when we got him already came with some bucket seats. Yes they were all torn, collapsed and horrible and they went to the dump. However what the PO had done to facilitate the fitting of these bucket seats was to remove all vestigial traces of the original seats and their mounting points etc. We thought long and hard about trying to make the seating arrangement in Camel as per factory but we couldn't find any parts locally that were any good and I already had the really nice 525i buckets - so it was decision made I guess.

First job of the day was to cut away the under-seat battery tray and all that associated sheet metal, which was a shame because it was the best part of the car. Usually they rust the tray out badly but Camel's tray was in pristine condition and solid as a rock - ahh well, it had to go ( no pics sorry). The we mounted the seat base onto the chassis and test fitted the seats just to see if the rails needed any type of adjustment - shortening in this case - but they were exactly the right length. At this point I was amazed at the lack of reinforcing that is under the seat base to take the seats - there is nothing, period! Obviously we will have to address this. Test fit of the seat base minus the battery box..

Attachment 128887

I decided to mount the tray temporarily to the chassis as well just to get an idea of how far the seats can recline and if the seats impeded at all the bolting together of the two parts - all good. Seat rails were a good length - with the seat rail pushed all the way to the back...

Attachment 128889

They just stopped short of the front of the seat base - perfect!!
Attachment 128888

And the rails were the perfect width too...
Attachment 128890

I also temporarily mounted the handbrake just to see whether the seats fouled it in any way - all good:
Attachment 128893

First order of business was to reinforce the seat base back-to-front to primarily withstand the weight of the occupants. I just could not believe the lack of strength here - maybe its the original seat mounts that provide the extra strength. Anyway, what I did was get some 2.5mm aluminium angle and make bridging girder between the rear tray-to-seat base mounting flange and the vertical front face of the seat base. The angle was 50x50mm and once pop-riveted to the existing centre opening flange it stiffened this area up incredibly...
Attachment 128894

Next was reinforcing the areas directly under the seat rail mounts so they don't pull through the aluminium in case of an accident. The design also called for supporting the weight of the seat back to some structural member and not just the aluminium seat base. This is what I came up with - supports the seat weight back to the steel sill underneath in the horizontal plane and also the angle that the tray mounts to in the vertical plane. Its 3mm steel so complies with the NCOP VSB14 Section LK in terms of seat mounts and reinforcement...
Attachment 128895

The front mount was similar - reinforce the corner and take the load down to the sill in the vertical plane. The seat base is sandwiched between 3mm steel layers for extra rigidity...
Attachment 128896

Inside mounts were considerably easier to design and to make. They consisted of a 3mm steel plate with a return flange bent across them to sandwich the vertical faces of the seat base. In the case of the rearmost mount, it sandwiched the tray-to-seat base vertical flange between one layer of steel in the vertical plane and two layers in the horizontal plane. No need to reinforce back to the chassis or other strength-member as they were in close proximity to where the tray mounts to the chassis so any kind of deflection here would be absolutely minimal...
Attachment 128897

The front reinforcing arrangement was similar - a vertical return on the upper 3mm plate, with a 3mm plate underneath the seat base. The aluminium bridging girder is sandwiched bewteen the steel plates back and front as well so in essence we have 2x3mm steel plates, 1x2.5mm aluminium plated and 2x1.0mm aluminium sheets directly under the seat rail mounting points - there is no way this is going to bend!
Attachment 128898

Everything is bolted together with 8mm Gr8.8 stainless dome Allen bolts and nylocs for that nice finished look. Test fit seat and have a sit - wow, solid as a rock! Mark out the seat rail through-mounting holes and check the ergonomics - good height, heaps of adjustment and very, very comfy for that long drive...
Attachment 128901


Ok, driver's side done now to move onto the passenger side. Make up a bridging girder for support...
Attachment 128899

Pop-rivet into the seat base...
Attachment 128903

Make up some more brackets as a mirror of the drivers side...
Attachment 128904

Attachment 128905

And then test fit the passenger side seat, mark out the M12 seat rail through-mounts and admire your work. Plugger weighs in at over 90kg, I am just on 90kg as well so our combined weight is in excess of 180kg. Both of us could not get the seat base to budge an inch even with only a handful of bolts holding it all together - I say mission accomplished!!
Attachment 128906

Here are some shots as to how BMW mount the seat belt anchors to the seat itself - all very nice and tidy and saves me making anymore fixtures to cater for the seat belts. I have just ordered some new lap-sash retractable belts from Seat Belt Solutions in WA - thanks Alex and Derek for the custom yellow belts - should look a treat next to the black leather seats. A little leather gaiter hides the buckle side...
Attachment 128907

And the loop-end simply disappears inside the seat, how neat is that??...
Attachment 128908

Anyway, that's it for the day. I would like to wish all the dad's out there a Happy Fathers Day and I hope you all got spoiled rotten!!

Cheers and thanks,
Tricky and Plugger

Tricky,

Just looking through the seat work. What height above the base does your seat finish?
I did a similar replacement on my previous 2A years ago with some Japanese sports car seats but found the height too high, causing forward vision difficulties though the windscreen. Not sure how tall Plugger is but after driving in a stooped position I pulled the seats out and cut the metal bases down and even had to trim the foam base down. I ended up I guess with around a similar height to the 2A original seat squabs. The seats were comfyer of course and did the job perfectly and the lower position gave better vision forward. Looking at your work I think you might find it 2-3 inches above what might be preferable.
Something to consider.