MGF: Misty Headlamps

Words and Pictures: Rob Bell
Acknowledgements to Geoff Smart
Dedicated to the memory of Geoff Smith

This page contains: The Problem | Re-chroming | Where for re-chroming?

Depending on the age of your MGF and its headlamps - and how often you use them, you may have noticed how feeble the light output has become. When you look at the lamps themselves, you can probably see that compared with an MGF with new headlamps, yours have a 'misty' or cloudy appearance. Unfortunately, I have some bad news for you: this problem only gets worse. In fact, my car recently (2004) failed its MoT on its feeble headlamp performance. Gulp! (See picture, right)

There are two solutions to this problem:

  1. Replace the whole headlamp with a brand new unit.
  2. Get the headlamp bowl re-chromed.

The problem with the former option is that it is an expensive option - and the problem will only recur over time. The advantage of the latter is that the underlying problem can be over come, and relatively speaking, is a cheaper option than wholesale headlamp replacement.

The Problem


Illustrating the problem: instead of seeing a mirror image of my finger in the headlamp reflector bowl, all can be seen is a rather diffuse reflection.

The underlying problem is not so much degradation of the diffuser lens ahead of the dipped beam reflector, rather a two-fold problem involving oxidation of the polished aluminium-plated plastic head lamp bowl and a lack of lacquer protection of the substrate plastic headlamp bowl. It appears that Valeo, the manufacturer of the MGF's headlamps, saw fit not to protect the aluminium film nor protect the plastic from heat degradation.

Oxidation of the aluminium reflector
A lack of a protective layer over the aluminium surface treatment is not such a problem on a sealed beam headlamp unit where the aluminium is isolated from the atmosphere - but in the MGF, this is not the case. Thus, after exposure to heat from the headlamp bulbs and to atmospheric moisture and oxygen, the film oxidation is an inevitable consequence. Instead of a nice silver mirror effect, the reflectors almost go white.

The consequence of this degradation of the surface of the reflector is a reflector that no longer reflects light in a coherent way - and the amount of light that is reflected is severely attenuated.

The only solution when this happens is re-coating. It isn't possible to polish the silver coating: I've tried, and all I achieved was removing the silver finish from the head lamp bowl!!!

This, however, may not be the whole story, as Geoff recently got in touch regarding some further investigation of the particular problems we're seeing on MGF head lamps...

Lack of protection of the plastic substrate
Geoff was recently able to lay his hands on a damaged MGF headlamp bowel that was otherwise to be scrapped so he could further investigate a problem that, in his experience so far, seems unique to the MGF. Under close scrutiny, he found that Valeo had another cunning cost-saving scheme under its sleeve- by moulding the plastic head lamp bowel to such high standards of surface finish, they were able to apply the reflective coverings direct to the plastic. In days gone by, the plastic would have received a lacquer layer to improve the surface ready for aluminium coating - a process that costs money - and by removing the need to 'improve' the surface finish with a lacquer layer, this cost could be saved. However, the lacquer layer also helps prevents the plastic layer from "gassing" - a process where the volatile components of the plastic evaporate under heat. Unsurprisingly therefore, hot head lamp bulbs over long periods of time can cause the plastic to gas - leading to a break down of the fine surface of the plastic and distorting the aluminium covering. Given the lack of 'misting' on areas of the head lamp bowel not exposed to the heat of the headlamp bulbs, this theory seems to fit the observation.

Any restoration of a used headlamp bowel is, therefore, going to need a fresh lacquer layer to be applied to the plastic lamp bowel.

Re-chroming - a long-term solution?

Geoff Smith
Reflector Restorations
I am deeply saddened to report that Geoff has recently passed away (summer 2006). As an enthusiast working from his home, this service is therefore no longer available.

I wish Geoff's family my heart felt condolences - and those from the many MG devotees who made use of his expertise and whom I know feel the same way.

I dedicate this page to the memory of a genuine motoring enthusiast, whom I shall remember fondly after our many telephone conversations.

The solution for me was to send off a spare pair of reflector bowls that Tim Woolcott had kindly given me to Geoff Smith of Reflector Restorations.

Geoff runs a small re-chroming operation in West Sussex, and performs a lot of work for Classic/ Vintage cars and motorcycles. Unfortunately, you have to be pretty handy at the DIY, as you need to send him the reflectors of your headlamps in a ready disassembled state. Fortunately, this is all pretty straightforward, and is covered here. A word of warning though - those headlamp bowels are incredibly brittle, so take a lot of care on how they are wrapped up for postage - drop Geoff a line before sending, and he'll advise on how best to package the parts.

For me, Geoff came up trumps: the reflectors were returned to me a few days before my F was due its MoT test - so when the poor ol' car failed due to tired lamps I was able to strip the front end of the car down, and reassemble my headlamps with new gleaming headlamp reflectors and return to the MoT testing station the next day!
The car passed its MoT of course, but more impressive was the immediate improvement in performance of the dipped beam. Hey - I could actually see things illuminated by them!

As Geoff also coated the plastic substrate and the silvering with a protective lacquer, hopefully the problem with reflector deterioration should be ameliorated for the foreseeable future. I'll keep you all informed! (Now two years on, and they still look as good as new! - Jan, 2006)

Where to get my reflectors rechromed?

As indicated in the panel, above right, Geoff Smith, who did so much to pioneer the rechroming of MGF reflector bowls passed away in the Summer of 2006 - which left MGF owners with a problem. Where else can the reflectors be re-chromed? Geoff Smart, a fellow MGF enthusiast has worked hard to find another supplier capable of meeting Geoff Smith's original specifications and prices - a task that I am sure was far from simple. But after negotiations with Peter and Colin at Dual Metallising in Birmingham, we believe we have a viable alternative service provider. At the time of writing, the cost of this service is (was) 70 plus VAT for a pair of reflector bowls - the price being inclusive of return postage. The scheme will work in much the same way as it did with Geoff Smith - and before sending it is certainly worth chatting to either Peter or Colin - particularly regarding packaging, as the reflectors often proved to be somewhat fragile - particularly in the hands of our Postmen!

Contact details:

Dual Metallising Limited

Unit 12/14 The Business Centre,
James Road, Tyseley,
Birmingham, B11 2BA

Telephone 0121 708 2748