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Old 16th June 2020, 07:07
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Mister Towed Mister Towed is offline
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I've made some positive progress over the weekend without any serious setbacks.

I finished off taping up my head fairing. It's only going to be a 'close enough' shape to work on out of the mould, hence the plug being somewhat basic -

Off the car to reinforce the lower edge it is very reminiscent of one end of a Viking longship, fit for a trip to Valhalla -

Back on the car I covered it with half a dozen layers of 500gsm CSM -

Leaving me with a basic mould for the head fairing -

The mould needs a little work on the inside: a bit of filler here and there, sanding smooth and painting, but it'll do the job once that's done.

Speaking of which, after a week or so for the paint to cure, I also set my hybrid 356/550 dashboard mould to work over the weekend.

As it's a two-piece mould with a pretty complex shape for the eyebrow over the instrument cluster it's definitely the most ambitious fibreglass item I've ever tried to fabricate.

Here's the mould clamped together after multiple coats of release wax had been applied -

Next job was to put PVA release agent on top of the wax. This is where I did have a bit of a problem, though: Following the manufacturer's guidance, I sprayed the PVA into the mould using a conventional gun with a 2.2 nozzle, but rather than a smooth, thin coat, the PVA just beaded on the surface, even though the first few coats were just a dusting. Googling it, I found that some release waxes cause this and some don't, and I was just unlucky enough to be using one that does.

I couldn't find any posts that said what to do about it, I figured I could wash it off and just go with the wax but didn't want the dash to stick in the mould, which could be a disaster.

Instead I took a 1" paintbrush and kept brushing the liquid out across the inside of the mould as it beaded until it started to set and stopped beading. That left a rather uneven coat of PVA on the mould, but I figured it was as good as it was going to get so I went ahead with the next steps.

After leaving the PVA to fully dry overnight, I gave the mould a couple of fairly thick coats of white gelcoat, brushed on as I don't have any thinners compatible with it for spraying (and it's the consistency of treacle out of the tin).

Once that went tacky, I used a layer of 30gsm 'surface tissue' making sure it was smoothed as far as possible onto the gelcoat. Then it was on with the resin and layers of 200 and 300gsm CSM to build up the dash in the mould.

As the dash eyebrow is quite intricate and impossible to get a roller into, I found it was best to fully stuff it with the lighter weight CSM and resin, ramming it home with the tip of a paintbrush to make sure there were no voids and that the eyebrow will actually be solid fibreglass.

Anyway, after leaving it for 24 hours to cure, the time came to see what I'd achieved.

Drum roll, please...

So far so good, the front part of the mould came off with some serious screwdriver prying -

Then the back of the mould followed suit, leaving a newborn dash moulding, complete with PVA placenta!

And after a wash with warm water and as sponge -

I was in tears (of joy) even if my new baby wasn't.

Okay, it's not up to pro standard, it needs quite a bit of work to make perfect - the gelcoat surface is quite pitted from where the PVA had gone on lumpy and there's a heavy moulding seam to sand out, but it's light, strong and the shape I want, so I'm over the moon!

Here it is dropped into the shell (prior to trimming) -

More later
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