Fog Lamp Restoration
MG TC LUCAS SFT 462 FOG LAMP RESTORATION
This article was submitted by Rob Grantham who is well known in the MGTCOC as a very fastidious and meticulous restorer. The lamps in the pictures show how skilled Rob is at bringing these old pieces back to life.
Here is his explanation of the steps involved.
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Separate the lamp reflector unit and rim from the lamp body. Note: The rim is held in place on the lamp body by a slot head, raised, countersunk setscrew, (with clamp plate) lower tab piece and an area of swedging on the lower edges of the lamp body. Remove the Lucas “King of the Road” badge. Also release the rim holding the reflector/glass unit by pressing down on the perimeter spring clips.
Remove the four (4) rivets (copper) carefully to release the steel base plate from the chrome plated body of the lamp. A small grinding tip used on the inside of the lamp to release the rivets is useful. Final release can be achieved by use of a fine punch tool and light hammer. Retain the copper earth wire holder located under the tail of the front, right hand side rivet.
Once the base plate is removed from the lamp body, examine the fine thread (⅝ x 26) stem onto which an affixing brass nut (long) is attached. If the threads have been compromised over time on the steel stem, it may pay to replace same. This will necessitate drilling out the “cross bar” on the steel base plate using a de-spot welding drill bit. This type of drill makes for a neat job and also leaves telltale metal as a witness mark for re-welding back in place on lamp reassembly. Check that the tab of the crossbar is not “wound” or bent offline. This tab functions to prevent the stem turning when the nut to badge bar is tightened.
The base plate and component parts, including the slot head setscrews and star washers which hold down wiring to the crossbar, the wiring hold down piece, the rim screw retaining plate, together with the spring clips securing the rim to reflector can now be taken to a reputable plater for re-cadmium plating.
Use a ⅝ x 26 die and re-run the stem threads before cadmium plating.
In Perth, Aeroplate is a highly recommended plating business. Anthony Lees is a thoroughly professional operator with work standards of the highest order.
The base plate and the base cone ring were originally painted black. The threaded stem was originally cadmium plated.
Attention can now turn to the chrome plated lamp body, rim, rim screw and nickel plated brass stem nut. Invariably, it seems over time the lamp body becomes damaged in some way. Located on the front of a car, particularly those vehicles which do not have bumpers, leaves this Lucas “piece of jewellery” open to abuse!
Before commencing work on the lamp body, it needs to be de-plated, together with any other chrome plated parts, by a trusted electroplater.
When you receive these brass lamp parts back from the plater, any imperfections, dents, pitting, mis-shapening, etc. may now not be so evident. However, use aluminium oxide abrasive paper, say 400 grade, over the lamp body surface and this will soon obviate the areas needing attention. Note: Cover the area which is stamped “Lucas SFT 462 Made in England” with masking tape before using abrasive paper. This stamping by the Lucas Factory was originally quite light and can easily be entirely lost in the linishing process - 800 to 1200 wet and dry abrasive paper can be used in this area later ready for light buffing.
Use wooden headed hammers and dollies first when beating back the brass into original shape. Sharp denting and “deep pick type” damage may alternatively require appropriate steel panel hammers. Small sand filled bags are useful as a backing for the beating action and help stabilise the job on the bench.
Eradicate dents including the area where the four (4) base plate rivets entered. After beating, Mill 2nd Cut Files can be used to plane off the worked surfaces. Abrasive paper of varying grades (increasing in number coding) can now be applied over the lamp body surface.
Final mechanical buffing with Sisal and softer cloth mops should render the lamp body ready for chrome plating. It is wise to get the designated electroplater to check the brass surface you have worked on before allowing final chrome plating.
The brass rim can often be mis-shapen as a result of frontal impact. Check for any ovality and or wind and rectify. Re-work the surface as per the lamp body.
The long brass affixing nut is sometimes in need of light dressing with a file. Originally this nut was nickel plated by Lucas.
The retaining rim’s setscrew slot can be brought back to “as new” by careful use of a jeweler’s file. You will need to replace the four (4) base plate rivets to lamp body rivets. Have them nickel plated in readiness for attaching the steel base plate to the lamp body.
When the steel base plate pieces are returned to you from the cadmium plater, you will need to re-weld the crossbar back onto the base plate if this was previously removed. Don’t forget to fit the threaded stem and the swivel washer before re-welding the crossbar. The stem is left cadmium plated whereas the base plate/crossbar is painted over in satin to gloss black. The large cone ring located under the lamp body was also painted black. Undercoat these parts first – mask off the threaded stem.
When re-fitting the steel base plate to the newly chrome plated lamp body, a dolly shaped to the head of the rivet will help prevent damage to the plated rivet head surface when peening the tail. You may even have access to a compressed air riveter for an even neater job. Don’t forget to place the copper earth wire holder in position before riveting over the front, right-hand side rivet.
The reflector and glass lens are integrally crimped together – unfortunately! I tend to like the “soft” silver glow from these types of reflectors and most units are presentable and practically adequate in original form. You may even come across NOS reflector units in your search for parts. Alternatively, the unit can be sent to Anthony Pearson in South Australia for dis-assembly and reflector re-silvering. He can release the glass lens from the reflector using a special lathe tool in order for the reflector to be re-plated. Anthony will then re-assemble the glass lens to the reflector.
Check that your globe is operational before fitting to the bulb holder. The delicate aluminium bulb shield usually only needs light polishing. It has been documented that at TC 4739 (9th February 1948) the fog lamp was changed from an FT27 to a slightly more modern SFT 462. There are two variations of the SFT 462. One had a “stepped reflector” (black line reflector division) with even, fine ribbing on the glass whereas the other had a more variable ribbed glass with “Lucas 462 Fog Lamp Made in England M5” cast into it. The other lamp components were identical.
I suspect that the locking washer preventing the stem nut rotating and therefore undoing, was originally a Thackeray washer.
I have deliberately omitted mentioning the Lucas “King of the Road” badge in relation to re-chrome plating. Generally, by carefully polishing (using Silvo) this badge with a soft cloth, you will revive lustre. Re-plating tends to remove the sharpness of the stamped lettering so avoid the process if the original chrome surface is acceptable. The retaining tabs on the Lucas “King of the Road” badge are delicate so care is needed in re-affixing to the lamp body.
Grease both the threaded stem and the countersunk slot head rim retaining screw before final fit up.
TF 3719, TF 9177, TF 5164
28th April 2011
Perth, Western Australia
Lamp prior to restoration
Lamp base plate and crossbar, tab is yet to be welded on
Lamp base and rim after beating, filing and sanding
Lamp body finally buffed
Fully restored Lucas SFT 462 Fog Lamp.