Sunday, March 30, 2008

Skinning complete

570 rivets later and the aluminium panels are all attached to the chassis (well, apart from the transmission tunnel covers that need to stay off for now). There were about 4 rivets that due to access difficulties were not possible to get in completely flush, so I'll have to accept a 0.7% failure rate on that job. Shoddy I know.

Getting on for two of the tubes of sealant were required - I fully expect it to leak like a sieve in the great British weather, but I've done what I can to prevent it.


The drilling and de-burring of the rivet holes was frankly tedious, and the riveting was hard work - if I ever do this sort of thing again I am most assuredly investing in a compressor and air-powered rivet gun. Using the hide hammer to beat the panels into the contours of the chassis rails was fun though!

Following on from the skinning, the foot controls were next - quick to assemble and install. It looks cramped in there for my size 10s - it'll be interesting to see exactly how many times I can accelerate and brake at the same time.


Next task is to form and fit all the brake pipes (or possibly sort out the wiring loom that is still lurking under the workbench).

Monday, March 17, 2008

Interior Colour Scheme

I thought I would start a poll (in the column on the right on http://smlight-thewidowmaker.blogspot.com/) to get some opinions on colour schemes for the interior. There's huge number of options and combinations; the entire upholstery, carpets and internal paneling can be done in a single colour, or a two-tone can be achieved picking out the inlays and piping on the seats and the piping on the carpets.

Summoning up ropey artistic ability, here's a selection of colour schemes:

A is the period colour combination - a dark red interior with the BRG exterior, there's a picture of that towards the start of the blog. B is the safe all black interior, C is black but with the seat inlays and all the piping in the dark red as a nod towards the original. D is the same but with the green carried through, and yellow in F. E and G are cream and black detailing on the dark red interior. And all cream is a possibility as shown in H.

Personally I quite like the black with dark red detailing in C, as it gives at least a nod towards the original. But I may change my mind yet...

Wednesday, March 12, 2008

Skinning mini-update

Now the engine has been temporarily put to rest, I've set about actually assembling the car. With a bit of manual assistance from my brother, I've moved the bodyshell off the chassis and have begun the fairly tedious process of drilling the hundreds of rivet holes required for the aluminium paneling.

This is the first time I've actually seen the chassis naked and unadorned (anyone under 18 or of a nervous disposition better look away).

Phwoar eh? Eh?

Anyway, so far I've gone through the process of clamping a panel, drilling pilot holes, fixing the panel with skinpins, drilling the remaining holes, and removing the panel about 10 times. There are I think about 8 more to go although some (notably those that would make the transmission tunnel inaccessible) are left until later in the build.

Skinpins are re-usable temporary mock-rivets, often requiring a specific hand-tool to fix in place and remove them. I got a handy set of the ubiquitous e-bay that are fixed using wing-nuts. Quite handy.

Hiccups on this stage are a missing GRP panel that I have been in discussion with Westfield to get sent down to me, and about 1 botched rivet hole on each panel so far. Many of the holes required are pretty inaccessible, even with a 90-degree drill attachment, leading to some over-sized or oddly angled holes. My plan here is to straighten and neaten them with a hand reamer and then fix them with a larger size rivet. If I mirror that on panel pairs then it may just look intentional.

Oh, I've been getting through a fair few drill bits too adding Drill Bit Factory to the White Spirit and Masking Tape Factories that would be handy to own if I ever do this sort of thing again.

Thursday, March 6, 2008

Stage 1 - At last!

This week I have mostly been finishing the engine. I think I'm fairly pleased with the result...


The idea was to paint it in keeping with what I believe the colour scheme of the original Ford Cosworth engine was in the genuine Super Seven; satin black sump, gloss British Racing Green block and a silver/grey head.

This is the first engine I've painted, and although I spent what seemed an eternity cleaning all the parts and preparing surfaces, I have no idea whether the paints chosen will perform well. I have no idea whether they will flake off, or catch fire, or catch fire then flake off - only time will tell.

I've used Halfords high temperature engine enamel for the sump as it claimed to require no undercoat, and it covered very nicely indeed. The block was first prepared using POR-15 and then painted using a gloss engine enamel that I found needed to be applied very sparingly to avoid any skinning and wrinkling (very possibly due to the temperature out in the workshop being startlingly chilly). And the head was painted with another undercoat-free engine enamel Sperex by Simoniz which again covered extremely well. An impressive melange of fumes resulted from all of these - a well ventilated work area was a necessity.

Once everything had been cleaned and painted, the re-assembly was pretty straightforward. I even managed to get the new clutch on with no pain - the only tricky bit was ensuring that the clutch itself was positioned correctly whilst the housing was bolted on. In place of a Mazda Special Service Tool (which there seems to be a boringly endless list of), or a loose transmission shaft, I improvised with the barrel of a chunky marker pen jammed in the end of the engine stand handle. It was a perfect fit.

The only hiccups being having to partially disassemble it near the very end as I had omitted to re-paint the timing mark on the crank pulley. I've read of methods of determining whether the engine is at top dead centre by removing the spark plug from cylinder 1 and either putting a dipstick in there or a piston-stop, either of which could end in tears. Besides with it being free-standing it didn't take a lot of time to get the cowling off the front, and it also allowed me to double-check the cam belt tensioner that I couldn't honestly recall tightening (it turned out that I had). I'm glad I put the mark back on - I'm looking forward to playing with the timing gun I've treated myself to later on.

Another bijou hiccup/annoyance was the small set of mystery components I had left over - nothing vital; a modest collection of brackets and clips. Although I had marked and organised most of the parts as they came off, I hadn't with the clips and brackets. I then found on re-assembly that they are not marked on the Service Manual - they may sometimes be incidentally drawn (and at least one I found drawn in the wrong position), but they are not marked as part of the assembly procedure. So, after many hours poring over the manual and searching the internet for clear pictures of MX5, I managed to get them back on one by one. All except one - the "Bracket of Mystery". I don't actually think it is part of the engine - it looks to me to be an earthing point off the original MX5 chassis that has become mixed up in the parts on my workbench. Probably. Well, it has a bit of red paint on it and that's good enough for me! I do know however, that if I ever do this thing again, I shall take photographs from all angles prior to disassembly.

There was one slightly more serious annoyance - I accidentally dropped a spanner and knocked a chip out of the body panel. A fairly small chip (less than 5mm diameter) but it is annoying none the less. I'm hoping that I can position a bonnet clasp or something over it to hide it. We'll have to see about that later.

So, the engine is all assembled - and I've even bolted on the fixing brackets from the kit, which I found strangely exciting coz it's the first part of the kit proper that I've done anything with. Stage 1 has formally begun - the assembly is go!

I just hope the engine works, works correctly that is, when the car is completely built. That will be a while away yet. The next task which I should be getting into this weekend is the drilling of hundreds of holes into the chassis for the subsequent riveting of panels. I've had a little practice with some scrap aluminium sheeting and box steel, and it went well. I just need to repeat that over, and over, and over...

And now, due to popular request - here is the "Bracket of Mystery"!