Exhaust

 I saw an old post from Facebook today, talking about the exhaust. More specifically it was the initial fit before the body went. 

It's been some time since I worked on the exhaust but I forgot how secure it was. It's basically sitting on the outriggers, so my initial plan of dropping the exhaust downwards is out the window. It basically needs to slide back to where the rear wheel is.

Fortunately, that seems to be very doable;

So I can undo it from underneath and bring out the can from the wheel arch. I'd have to remove the wheel though, which makes it fiddly but not impossible. 

So that's the plan. Measure up the right angle pipe against the bodywork, draw out the exhaust to tack it, refit to check, blah blah blah. Then I need to make an exhaust trim for the body, so more aluminium to polish. But what that will allow me to do is replace the gaskets and tighten up the exhaust, ready for ignition.

Light fittings and speedo cable

 When I fitted my lights, I was aware that they're not the best quality. To be fair, 8 lights for £30 was never going to be top quality, however these are bordering on unusable. Actually, scratch that, they are unusable. One thing I had done is add the 'fix lights' task to my to do list. It all stems from two of the lights not properly locking in the bulb, and I just know the IVA would be where it manages to work itself loose.

So without much debate or questioning myself I set about replacing the offending soft plastic parts. I could reuse the rubber, and the electrical contacts weren't too bad, so it was just the plastic part. A quick session on Onshape gave me a few prototypes;

This was the light fitting itself (bottom) which was mostly fine, as well as four attempts at the 'bayonet cap' thingamajig. I say four attempts, but actually this was just three attempts to get the size rights, then a fourth attempt at printing one too many pieces as one print. I can't get the hang of supports, and it's even worse with PETG because it's so much stronger than PLA.

Anyway, eventually I got a holder the same dimensions as the original;

With the wiring back in everything lined up;

It also went back on the car really well so I'm happy the print is good. There is just one issue, basically I'm replacing the visible part behind the lens. Which means that while black looks good as a backdrop (and won't change the light colour), I actually have to replace all of them rather than just the broken ones! So I've spent two half days just running the parts off the printer and gluing them together. I reckon by Wednesday I will have replaced all of them and be all sorted with lights... for the second time. Ah well, as I said I spotted it very early on and it's been a job that needs doing.

Another job that needed doing was the speedo cable. It needs to be pinned in place inside the drivers side footwell, mainly because the Mark 1 MX5 gearbox put it there in the first place! This is how it comes out of the gearbox and into the drivers footwell;

Now once again this has shown why doing one job, removing it, then doing another is not the best plan. The way that I had this was looping up next to the pedals and back on itself;

The problem is that the loop is long enough to go where the firewall is now, which obviously wasn't a problem before but it is now. Given the cable can't be shortened or rerouted (it can only do a certain degree of rotation before it stops working), it has to go through the firewall;

Fortunately that black glue line above the holes is where the radiator tank sits, so it won't be that visible once it's all blocked in. However what I do need to do is blocking both those holes with appropriate grommets. I'm thinking of 3D printing some but I'm not sure it's suitable for something going through a panel. But then the original one had a plastic bracket supporting it's exit through the panel. Hopefully the locostbuilders massive (which is becoming less massive by the month) will have some opinions. Blind rubber grommets are the most obvious choice, but I'd have to heavily cut them to get them over the speedo cable end. Both ends are about 25mm in diameter, quite a bit more than the 10mm cable diameter.

What else is there to talk about? Oh, the fan is fitted. I didn't realise I'd actually planned that out, so I actually didn't have to do any work apart from finding slightly longer bolts to go through the fan and radiator. 

Ah, that reminds me, I need to cap off the radiator. The rad comes with a location for the thermostat (I think) on the original Polo. But on the MX5 the thermostat is on the engine block. Even the bypass valve is also located on the engine, although the hole wouldn't have been any good for that anyway. So I need to find something to bung it up with. I'd best do that now while the printer is whirring away.

(Five minutes later). 

OK, nothing I have comes close, either too big or too small. But a quick google suggests it's an M22 x 1.5 and normally reserved for the fan switch. £4.50 for a suitable blanking cap, It'll get wrapped in PTFE then inserted. I still need to add the T piece for the overflow but that's just a matter of planning. In theory I could fill up the water and check for leaks, although I doubt things would get leaky until it got hot. 

(The next day)

So as I watched TV last night it did occur to me that 'what happens in failure conditions'. IE if the three parts of the lightbulb holder should decide they don't want to be attached to each other. And I think I've got it covered...

First off, the rubber boot will keep everything in line. Then if something should fail inside, the bit that screws to the car is also the bit that holds the boot and the lens in place. Furthermore that same screw also fixes the ground wire in place, so again it's belt and braces. The only thing I can't sort is if the screws for the lenses break and I lose a lens. but that would have applied to the original ones anyway, so overall I've got it as secure as possible. Hopefully Mr IVA will agree.

And talking of IVA, the speedo cable going through the metal work as above isn't too much of an issue. An LCB response confirmed my thought that the cable would be steel braided inside anyway to cope with the rotation, so as long as the edges aren't sharp they don't need to be soft. So 3D printing it is! 

Arches and weights

 First fun job, the car weight. I got my postal scales and tried them out on the weekend. First issue was the batteries supplied were garbage, but luckily it came with a small power supply so it was easy enough to plug in. Now granted I should have lifted the other three wheels up (and be doing it on a flat surface), I got this from the front;

And this on the rear;

So on the face of it, 722Kg (when added together) may not seem too bad. An average Haynes is 600Kg, and I've got a full body plus framing to go on top of that. I do have some bits missing, for example there's no coolant or fuel in the front or back respectively. The driveshafts and propshafts were in the boot rather than attached (so shouldn't change the weight too much), but the brake calipers weren't on so that alone is 2-3kg's per corner. I reckon if I can get it all in for 800Kg's I'll be happy. 

Now, on to the arches. I needed to get them fixed in place and I was struggling for a solution. Turns out some coathanger wire did the trick. Suitably glued to the underside of the arch gave me a fixing point;

Then with comparable holes in the bodywork I was able to mount them. I added a few more on each arch to preserve the curve (needing a couple of overnights for the glue to cure). I ended up with this;

I really like the result to be honest, they look quite purposeful and keep with the overall 'rough rally' look that I'm after. Rears are similar;

And while I could get to both drivers side and the passenger side front, the passenger side rear hasn't been touched yet. I need to roll it out a bit to get the holes drilled and pins located. 

Underneath the front arch shows the pins in place and the cut line;

I didn't forget that part of these front arches is so I can get a greater clearance on the bodywork, as I still only have about half inch before the wheels introduce themselves to the GRP. While the suspension is quite stiff, it needs more travel than that. I'll cut the GRP back to the first line on the tape, then use new fibreglass to make it permanent. The pins can stay in place for an extra level of reinforcement, I'll just have to bend them flush to the bodywork under the arch. 

I did briefly consider keeping the arches as bare metal, but it really wouldn't survive the elements. So they'll get etch primer and paint along with the body. Again, comparing it to the inspiration for much of my work I think it'll be a fair 'homage' to the original;

I just need to find an appropriate time to get the arches fitted permanently, after all working with resin and fibreglass is smelly if nothing else. I suspect 'outside' will be the order of the day for that job!

One last photo, the seatbelt covers;

The superglue did 'ooze' in some places and it turns white when it dries, so I think I'll have to paint them. I was tempted to paint them anyway, I think matching them to the bodywork colour should be good. I just need to ensure the paint doesn't leak through on to the belt!

Rear arches

 A nice little project for this weekend, the rear arches. In the week I set up the arch template that I'd used on the front, essentially a wooden template that is the same size as the wheel and provides an endpoint to the arch. Because the rear doesn't need anything removing from the arch, I didn't want to set it quite as high as I had on the front, so I jacked the car up to suit. (I didn't want to cut the template down in case I needed it again!). Once I'd found a pleasing height to the arch, I started with an 80 degree angle and wooden sticks at every ten degrees;

Of course, at this point I didn't realise that it wasn't quite enough of an arch! The IVA manual has an initial requirement of 30 degrees forward and 50 degrees back, but also at the back it needs to finish lower than 150mm above the axle. To be honest, because the bodywork is raised where it is, it would have probably finished at the right height anyway, but just in case I added another ten degrees.

Then I needed to fill in the gaps with more sticks, and a layer of masking tape just to make it easier to work with;

A quick line and curve on both ends to make it look nice;

And a paper template to pick up the pattern;

Some aluminium fettling later, and I have a wheel arch;

As I was cutting the aluminium I simply cut a mirror image version for the other side. 

So I now have four arches. I also spent part of my garage time cleaning up and making sure I have no more excuses to avoid the wiring!

Well, one more excuse. The arches currently has no method of fixing (as mentioned previously) but the rears in particular don't even have a suitable mark where they should go. I'm thinking of some temporary fixing that might allow the arches to fit unsupported. I'm thinking about three/five drilled holes where the arch will sit, thick enough for stiff wire that can then be attached (glued?) to the arches. That way it can be fixed in place, fairly rigidly, and I can work with it as is. When it comes to fibreglassing them in place, the pins will serve as a cutting mark as well as a base for the GRP. 

The last thing I did this weekend was a visit to Aliexpress, for a magnetic inclinometer, a laser level and a 300Kg scale. With those I should be able to do wheel alignment, or at the very least camber front and rear. Toe will need the steering rack properly bolted in before that can be done. 

Little jobs

 No wiring this time, I will get there eventually but not for now. Brain trouble rather than wiring trouble, maybe another time for that.

This is a couple of small jobs that I've had on my list for a long time. First the seat belt reels. I doubt they'd have failed the IVA with them being bare, but given they're hidden behind trim on the MX5 they are pretty ugly bare units. So I designed and 3D printed a small box for them to live in;

(The clamp was there to just stop the seatbelt from retracting!). The two halves will be glued together, I'm not expecting any maintenance on these so gluing the seam should be fine. I'll do it with the belt fully extended though, I don't want superglue dripped on the belt. It's a really straightforward shape but only the near half will even be visible (the belt will come out the top in it's final position). Then they can bolt in place.

Next was finishing the seats, I went to town on the headrest edge and really trimmed out all the overlapping pieces. The seam on the back board is absolutely spot on if I do say so myself, I'm really happy with how tight they've ended up;

I couldn't have got it any better. And with the black fixing screws matching the dash;

I think they just work really well. 

Next, VIN stamping. This was just a trial but I think it worked;

That's a centre punch rather than a letter stamp, and a paper template to show where the holes should go. I'm thinking of making some 3D printed guide for the stamp to make sure they end up in predictable places (IE straight lines!). Once I've stamped the whole VIN then it'll get welded in place. Given how much this small piece of metal curved I don't want to be stamping direct into the frame!

The last update is for my rear fenders/arches. I did the fronts a long time ago, but I didn't get round to the rears. Using the same method I'd done before, I got the wheel template in place against the body, then using an 80 Degree guide I glued lollipop sticks every ten degrees around the top. That was yesterday, so today I'll go fill in the gaps then make a paper template from the surface. After that it's over to aluminium to cut a left and a right, then they'll be ready for attaching. 

Ah, attaching... I've still not figured this out. I do need to trim the front arches to make sure there is wheel clearance, but on the other hand it also means there's less material to attach to the fender to. Screwing or riveting won't work, I don't want a visible fixing and I don't have anything to screw through anyway. The only thing I can think of is to;

• Temporarily fix the fender in place (with tape most likely)
• Use fibreglass to build up underneath.
• Take the aluminium off to clean up the fibreglass.
• Bond the aluminium back on.
• (add some discrete screws for reinforcement if necessary).

The main thing is what width to do the fibreglass. In theory I could do it right to the edge (and beyond) of the fender, then actually the new fibreglass would become the fender (after trimming). More likely I think an inch or so of 'lip' protruding from the side of the car for the aluminium fender to glue on to. The lip would also give me the option of screwing the fender in place, then a bit of filler to smooth over the screw holes would finish the job. 

I'm going to try it on the front first, mainly because it's better access but because I can get to the bottom quite well just by opening the bonnet. The rear arches will then follow whatever turns out to be the best plan. 

Thinking about it, the extra lip formed on the arch will also restore the stiffness of the bonnet. As I cut away the arch I'm going to lose a bit of strength in the car. 

Post Xmas catchup (seats and electrics)

 

After a lot of messing about, I finally have tall enough seats... unfortunately it would appear I took no photos of the extensions! Ah well, at least they're solid to the correct height which should be good for IVA. The only thing I found on the way was the join between top and bottom;

It's a bit ugly and tatty, but it's because it's a triangle of metal that doesn't really accept staples. So back to the 3D printer for that;

Some simple black covers to finish it off. Now, the back... the original plan was to use a flexible steel 'clip' thing that is used for regular seats. The problem is that it needs stapling to the back. This was complicated for two reasons. First, the stapler I had was cr*p and is now in the bin, and second I couldn't get it close enough to the edge to make it fit;

This shows how much material was left up top once I'd got past the extension and the metal, and on to wood. I couldn't do that with the clip. So it's back to a wooden panel, and to be honest I think it turned out brilliant;

The black screws match the same fixings on the dash so it really brings things together. The lower portion of the panel is also tight against the back, but the top needs a bit of work;

The pleats are thicker than the leather so it holds the cover away from the surface. I need to trim the pleats so it can fit better. It shouldn't be difficult but it's one of those things that if I get wrong I completely mess things up. So I've left it at this for now;

Short of a bit of cleaning, that'll be the interior finished.

I also made a mount for the air flow meter, just some bent aluminium and screws into the chassis;

It's very secure now so I'm happy. Oh, and one more leather covering, this time the cowl;

The tape isn't permanent, this is just while the adhesive set. It looks very good for the top, I need to do the bottom in the same way. I also need to check it doesn't foul the steering wheel though, it's a bit tight.

And talking of being tight, now the seats are in place and padded there's not a great deal of room for seat belt fixings. The inner edge is the fixed plate;

It doesn't have to move so as long as the belt isn't damaged as it's fixed then I'm ok. The outer edge is for the seat belt clip;

Again, this is fixed tight and then the buckle lives above the seat. I just need to make sure the bolt heads are out of the way. 

I've finally plucked up courage to do some wiring too, so I've routed the indicator wires to the right places. That covers the indicator bulbs, the hazard switch, the tell-tales as well as the correct number and type of fuses. Next one to do will be the brake lights, which also includes the brake pedal switch and the fluid sensor.