Wednesday 13 January 2016

Hood Stick removal and Boot Cover Replacement with Guide

After the car weighed in at a considerably 'tardy' 575kg (with 16.1kg of fuel) last year, I seem to have caught the 'weight saving' disease that many seven owners are also infected with... So last year I made the decision to try and remove as much unwanted 'stuff' with a view to still keeping the car looking nice.

A few bits and bobs were removed, and having changed to an aero screen (with no intentions of ever putting the screen back on) I thought that the next quick and easy weight saving would be to remove the hood sticks and replace the boot cover.

I ordered the new boot cover towards the back end of last year, but as the car hasn't been with me for the last couple of months I couldn't remove the hood sticks and fit the new cover, so as part of my 2016 prep here is the removal and new boot cover refitting guide.

Now onto the Hood stick removal and boot cover refitting guide.
This guide is just the way I found it worked best, and I'd suggest reading the whole post before committing yourself.

Firstly undo all of the poppers on the boot cover and velcro around the top of the roll bar as per the picture below which should give you good access to the hood sticks and inside of the boot.
Getting access to the hood sticks
Getting access to the hood sticks

Removing the hood sticks is actually very straight forward.  Literally undo these bolts on both sides, and unscrew the two self tapping screws holding the nylon fabric strips into the inside boot lip and the hood sticks are free!

Removing hood sticks is only a matter of undoing two bolts and two self tapping screws
Removing hood sticks is only a matter of undoing two bolts and two self tapping screws
With the hood sticks removed - there's only one thing to use... The 'new' suitcase scales!  The hood sticks weighed in at 1.5kg, so not a bad power to weight saving for just a few minutes work.  Time to store these along with probably another 50% of a Caterham I have in 'spares' in the loft! 

Caterham hood sticks weighed in at 1.5kg
Caterham hood sticks weighed in at 1.5kg
Now remove the top harness bolts - if you've not built your car it's worth mentioning these are longer than you may think!  The four self tapping screws for the poppers also need to be removed, and that's the boot cover freed.
Remove the harness bolts and self tapping poppers.
Remove the harness bolts and self tapping poppers.
Now, and I hear the drum rolling... Here come the kitchen scales for the first time in 2016!  Time to weigh the old boot cover.  The reason for weighing this is there is more material to allow for the hood sticks, and the new boot cover will naturally have less material and I wanted to see if there was any substantial difference.
The boot cover (for cars with hood sticks) weighed in at 832g
The boot cover (for cars with hood sticks) weighed in at 832g
Before refitting the new boot cover, I wanted to weigh this too.  However, and strangely enough the boot cover is supplied with a metal strip which needs removal - I'm unsure why it's there in the first place, but that's just the way it is.  So for those of you who are perhaps building your car and fitting your first boot cover, yes you do need to pick away at the stitching of your lovely new boot cover to be able to remove the metal strip.  I removed the stitching on the passenger side of the boot cover, slid out the metal strip and superglued the black plastic edging together.
Removing the metal strip from the passenger side of the boot cover
Removing the metal strip from the passenger side of the boot cover
With the metal strip removed, the only thing to do now was to count out the number of fasteners (for a fair test) and to weigh the new cover in!  The new boot cover weighed in at 578g which is a MASSIVE saving of 254g, but added to the hood sticks that are now off the car it's a combined weight saving of 1.75kg which equates to 'around' an additional 3.5-4bhp / tonne.
Caterham boot cover (no hood sticks) weighed in at 578g (inc fasteners)
Caterham boot cover (no hood sticks) weighed in at 578g (inc fasteners)
The next step is to align the leading edge of the boot cover with the top of the rear firewall (behind the seats).  Mark the boot cover where the holes need to be cut for the seat belt bolts and the popper fasteners (I used a paint marker) .  It's worth triple checking the holes, by lifting the front of the cover and replacing quickly in a flicking motion which like one of those flip books and gives the impression of the marked area over the holes.
Leading edge of rear boot cover marked up ready for holes to be cut
Leading edge of rear boot cover marked up ready for holes to be cut
Now to cut the holes... and the only tool I've got to cut through the boot cover is this derisory punch tool contraption (see below)... I really don't know of a better solution, but this does work - if somewhat, how can I say... 'tiresome' on the hands... It really is hard work punching through the double thickness material, and you need to punch four holes (on the largest setting) for the seatbelt bolts, and using the next size down a single hole for the popper fasteners.
Using punch tool to cut holes into the boot cover
Using punch tool to cut holes into the boot cover
With a hand as red as an embarrassed teenagers face, the holes should be cut in the front of the boot cover.  It's now worth fitting the front of the boot cover to the car, and fully tightening all the bolts, so that everything is nice and secure for the next step.
Front of boot cover fitted
Front of boot cover fitted
With the front of the boot cover snugly fitted it's time to mark up the rear of the boot cover for the poppers.  Ensure you pull the cover as hard as you can, and then with your finger push on the outer of the cover which will make the male part of the popper protrude into the cover material.  You can quite easily feel the centre of the fastener and again mark the boot cover with a paint marker.  It's worth double checking your markings (using the 'flicking' method I mentioned above) before you start punching your holes out.
Rear of boot cover marked ready for hole punching and poppers to be fitted
Rear of boot cover marked ready for hole punching and poppers to be fitted
Once you've marked up the boot cover and double checked your markings, remove the boot cover from the car and get the hole punch ready for action!  Using the third largest setting on the punch tool, punch through the boot cover to make the holes for the poppers to be fitted.

With all the holes punched, and no doubt a sore hand again! You'll need to get the dot fastener tool out.  Put the fastener in the rounded part of the tool, and the socket in the top part (as pictured below) then the metal into the brass section of the fastener then using a metal hammer a couple of light to medium taps and it'll be all secure.  Repeat for all poppers.

Fitting the poppers to the boot cover using the dot fastener tool
Fitting the poppers to the boot cover using the dot fastener tool
Now the boot cover should be ready for fitment.  Simply fit the harness locating bolts, the male fasteners on the leading edge, then 'pop' the rest of the cover in place, and it should look something like this:-

Caterham R500 with new boot cover (without hood sticks)
Caterham R500 with new boot cover (without hood sticks)
In summary, and if I done it again I'd probably just remove the hood sticks, and leave the old boot cover as the hood sticks equate to the majority of the weight saving... Plus, the new boot cover was £276 (I think) from the Caterham parts site, so over £1 per gramme saved!
 
Next post will hopefully be the carbon interior refit!  I can't wait to get stuck into this one... The only hold up is the final three panels which should arrive tomorrow :-)


6 comments:

  1. Daniel - have you/are going to remove the wiper motor and mechanism? That is a significant weight.

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    Replies
    1. Hi Charles - yes I think I will be doing that too!

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  2. The introduction of another set of scales is just genius. A man (or woman - sorry Lorreta) can never have too many scales or indeed torches. Why don't you set yourself a goal weight and then see if you can get down to it, Fatbusters style? I challenge you to 540 KG.

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  3. Daniel, glad to see you back on the blog and fettling the Seven. The metal strip in the boot cover is there to add rigidity to the cover's leading edge, which does not benefit from the tensioning effect enjoyed by the rear of the cover being folded over the car's rear body panel. Without the metal strip, and by screwing the popper fasteners onto the rear bulkhead directly through the unstiffened boot cover material, the cover's leading edge will in time sag rearwards in between the fasteners, leaving you with an unsightly untensioned boot cover. You could replace the metal strip, without the weight penalty, with a suitable fibreglass or carbon batten used in dinghy sails. Add lightness!

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