Sunday 15 September 2013

Day 15 (Full day)

OK, been a while since I updated the blog, mainly because I've been busy with a few other things and as a result work on the car has had to take a bit of a backseat. I managed to get one evening last week to work on it and all of today. Quite pleased with the progress actually so here's what i've been up to.

Indicator Pods

I started by getting to grips with the lights. Both the front Indicator Pods and the front headlights still needed to be fitted. First up it was the Indicator pods. The instructions in the guide are actually pretty good at explaining what to do here. Its best to start by fitting the rubber edging around the underside of the pod. I didn't do this but I think If i were to do it again, I'd probably apply some glue to the edge of the pod before applying the strip. Especially around the back of the pod where the cut away is, the edging likes to lift off. I found the hardest part of putting the pods together was actually getting to the backside of the bolts so that I could hold the nuts in place whilst I screwed the indicator light platforms into the pods from the front. Here is a pic of the solution I found which worked best. To be honest the one I'm doing up isn't that difficult to reach but there is one right at the back which is tough to get a socket onto.

Assembling the Indicator Pod

Front Headlights

With the pods done, I then moved on to fitting the headlights. The headlights come assembled so the first step was to remove the glass and then take off the electrical connectors that power the headlight and sidelight respectively. This then leaves you with the headlight pod with a threaded stainless tube at the bottom. This should be fed downwards, through the indicator pod and through into the hole at the top of the headlight bracket. All of the wires for the headlight pass down through the middle of the threaded tube. Once through the bracket, a big nut screwed on from the bottom holds it all together.

Assembling the headlights

By this point I thought I was doing pretty well and could see that the headlights would be finished imminently. After all, there was just the wiring to do which couldn't be that hard could it?

As it happens, this proved true for one side of the car, each of the wires for the headlight easily finding their way down the headlight bracket tube and into the engine bay. I had one side cracked within about 10 minutes with just the other side left to do before I could stick my feet up for the evening, excellent. I'd agreed with myself that I'd leave the final part of the puzzle (connecting the wires into the econoseal plug) until the weekend.

2 hours later and I was not a happy bunny. I could not, for the life of me, get the damn wires to go through the tube. They'd pass down it easily enough but I couldn't get them to go through the grommet at the far end where they are supposed to exit into the engine bay. In the end, I gave it up as a lost cause and decided I'd see what Blatchat had to say about the problem and also vowed to give Caterham a call in the morning to see how it was normally done at the factory.

The suggestions from Blatchat that came back were both good and varied, the best suggestion appearing to be to cut off the connectors from the ends of the wires (see image below) and then either re-solder these back on once the wires were through or better still, get some new connectors and fit them onto the wires using the correct crimping tool. Didn't stop me having a go at threading some strong cotton back up the tube and trying to pull the wires through though. Didn't work as it turned out.

Not the best approach 

I got hold of Derek at Caterham the following day to get his view on things. Apparently down at the factory they build the whole headlight and headlight bracket assemblies off the car and then, at the point at which the front suspension is fitted, fit the whole lot to the car in one go with it being a lot easier to thread the wires through the final hole with the bracket loose from the car. Apparently the build guide is to be updated soon to reflect this as it will definitely simply things but as Derek kindly pointed out, this wasn't going to be much good to me having already built most of the car.

Derek suggested two approaches to me that would work though. The first being to take the headlight bracket back off the car again with the primary issue here being that the front ARB passes across the top of the bolt head that would need to be removed. Apparently you can undo the ARB brackets and drop the ARB a bit to give you access and I could see how this would work, but In the end I preferred the second approach more (which backed up those suggestions made on Blatchat) which was to cut off the connectors, thread the wires through on their own and then, assuming I'd been successful, put some more connectors on the ends. Derek kindly agreed to send me some more of the connectors in the post so I got on with cutting the wires and attempting to thread them through in anticipation of their arrival.

This exercise still wasn't exactly plain sailing. I managed to get a couple of the wires through on their own but not all would go through at once. In the end I came up with a neat solution which was to pass a couple of sacrificial wires back up the tube from the end nearest the engine bay and using them to pull the wires I wanted back down it again. I could only get 2 wires back up the tube in the end so I bunched the 5 cables I needed to feed back down into a set of 2 and a set of 3 cables. I then soldered the wires together and taped around the connection with sellotape to make sure nothing would snag as I pulled it through. It took some shingling around with the wires and puling them back and forth but they did eventually go through. 

Wires finally through to the engine bay

So those were the bits that I managed to get done during the evenings this past week. Saturday was a write off as I had other things to do which only left Sunday clear for me to do a decent stint on the car.

Cycle Wings & Front Repeaters

The weather was actually pretty good when I awoke and, having heard that crap weather was due by lunchtime, I decided now would be a good time to get the side repeaters and cycle wings fitted so that I could complete the assembly of the econoseal plug and connect all of the lighting at the front into the main wiring loom. First step, drill out the marked holes that were already waiting for me on the wings (came like that from Caterham) using a 5mm drill bit.

Drilling initial holes
The guide then tells you to open up the middle hole to around 15mm which I did with the Dremmel. I'd recommend this approach over using consecutive larger drill bits for the middle hole. I tried this initially and could soon see that it was going to end with lots of cracks and chips to the fiberglass and paint finish so I stopped and opted to sand it to a greater size which didn't take very long either.

Making space for the front repeaters
The front repeater was then simply passed through the holes and was bolted on from the underside. Now it was time to fit the wings to the wing stays.

The Assembly Guide talks you through the steps needed to bolt the wings onto the car and indeed this is the usual approach for self builders with the wings coming pre-marked so you can see where you need to drill. I'd seen on a fellow 7'ers blog though that you could also take the approach of bonding the wings on so as to avoid any unsightly bolt holes that would be needed through the tops of the wings. I duly bought the necessary tools (BigHeads & acrylic bonding agent) during the week so had these ready to go.

The first step was to clean the underside of the cycle wings and the tops of the wing stays with Isopropyl alcohol to make sure the surfaces to be bonded were nice and clean. The bigheads sit directly on top of the wingstays and are then attached to them using cable ties. With these then loosely fixed in place, I could set about aligning the wings with respect to the tyre, a job made considerably easier with the aid of some masking tape appropriate markings to show the central line of the wings. These can then be aligned in relation to the central cut outs in the tyre tread.

Left/Right alignment of the Cycle Wings
The trickiest part of alignment is making sure the overhang at the front is correct. I did this initially by putting my finger on one of the marked holes and then, whilst looking up from underneath, looking to see whether my finger was aligned with where the Wingstay would need to be should I have chosen to drill it. With it aligned, I then looked down vertically from above at the forward edge of the wing and marked a line onto some tape that I had put onto the tyre. With all my visual cues in place, I quickly took the wing back off, made sure my BigHead fasteners were all aligned properly and then duly covered them all in the acrylic bonding agent. I used a 2 part adhesive called BigBond FS Acrylic. It mixes together automatically as you use it to activate it. I gave a good covering over the tops of all 8 of the BigHeads I was using (4 for each wing), then put the wing back into place and pushed down to make sure I got good contact. I then temporarily stuck the wing in place with some more masking tape.

Wing starting to bond to the BigHead fasteners
Within about 30 minutes the adhesive had worked its magic so I jacked the car back up and took the wheels off again. I then used what little adhesive I had left to go around the backside of the fasteners to make sure everything would definitely stick.

Wings bonded in place

Top down view of cycle wing

Now all that's left for me to do is get some polish and see If I can remove the 2 blue dots which look to have been put on with a marker pen. I had a go at a little bit of one and they do seem to be removable which is a relief.

The last activity for today was then to fit the hoodsticks (simple) before test fitting the roof. There are still some fasteners that I need to add to the sides of the car to locate it fully in place but other than that it does seem to fit pretty well. Some of the poppers are quite hard to get on though but I guess the vinyl will stretch a bit over time. Here's what she looks like tonight (albeit with the hood not properly fastened in place)

Very close to the finish line
Next on the list is the doors and the arm rest brackets which I hope to get done one evening this week before doing some final tidying of the wiring and sticking on all the necessary bits and bobs ahead of the IVA. Oh and it could do with a bonnet and nosecone shortly too!


  1. Tom - buy some extra wide cable ties for the Bigheads. The vibration does mean that they tend to rub through over time, so the wider your cable tie, the longer they last.

  2. I was wondering about that so thanks for the tip Charles, I'll have a look and see if I can find some.

  3. Looking good. Nice info on fitting the wings. Are the wing stays pre-drilled or not?! Wondering which way to go with them as I may have black front wings and get some black bolts. Not keen on the standard wing indicators. Wonder if it would pass iva with some smaller smoked ones?!

  4. I thought it was going to be hard work bonding the front wings on but as it happens, it took me about 3 hours in total to do it and that included fitting the repeaters to the wings. I'd highly recommend doing it this way now that I've done it. The adhesive seems to have set like concrete which is great.

    I also undid the cable ties this evening that were holding one of the wings on. I had noticed that the wing seemed like it wasn't quite horizontal. Having removed the wing I could then give the wingstays a few whacks with a soft faced hammer to 'adjust' them so that the alignment was true with the tyres. New cable ties went back on to secure them again in place. Whole thing took me 10 minutes.

    To answer your question regarding the wingstays, No they are not pre-drilled, and that includes the hole that you also need to drill in order to fit the ground wire for the repeaters. In the end, I elected to drill a single hole horizontally into the wingstay (only went half way through the tube). I then riveted the ground wire to the wingstay rather than opting to bolt it in place. It looks neat and seems to do the job nicely.

  5. Oh and I don't like the look of the repeaters either. I can see me switching to some carbon wings at some point in the future though so I think at this point I shall simply not refit them.