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  RESTORATION OF AN H.M.V 907 TELEVISION SET FROM 1938
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It comes apart too, after a little persuasion, revealing that its end is fastened by two nails.

It is then decided to remove both plinths. This will enable them to be restored separately from the cabinet, producing a neater, tighter looking final result down bottom-side. Also this will facilitate better access to the woodworm for treatment!

The original (untouched) plinth needs more persuasion to come off. The screws are tighter and the surfaces have also been lightly glued. A blow from a soft faced hammer soon breaks the bond.

 Here are the two plinths ready for critically matching in length.

Using a Stanley knife, the mortise section is broadened by the degree of shortening required on the plinth. The cut out section is then put back so it sits on the other side of the tenon. In this way the rear skirt mounts further in. Everything is glued back together and the slight excess length that now sticks out is ground off. Result: a plinth that's still as strong as before but ¼ inch shorter !

 A quick check of the cabinet reveals several tiny chips and pits needing filling. Here's one on the inside of the rear-facing edge.

On the whole though, I am highly impressed by the thickness and high quality of the veneers on this cabinet. Just as well, 'cos there's so much of it !

The plinths will remain off for now. After another hour or two of rubbing, at last the cabinet preparation is completed. This view is somewhat deceptive - in places there are still patches of veneer dust obscuring the grain pattern.

It's always a good idea to let a cabinet 'settle' few a few days at this point, before the first finish goes on. Tiny dimensional changes can still occur in the seating of the veneers.

In a cabinet such as this, where a lot of filling and shaping has been required, there will be places where spots of plastic wood have to be camouflaged so they will be invisible. A lot of this is done by playing various tricks with the toner (clear wood-tinted lacquer) that will be going on later.

But there's no harm in making this process easier, by right now filling in some detail with a cotton bud charged with wood stain. To get this right, a quick wipe over with a little White Spirit helps merge in the borders and also gives a useful preview of how things will later look, once the lacquer goes on...

The first coat of high-build primer goes on. As you can see I'm doing this outdoors. Even so, appropriate face masking must be used. Note a mask been made to preserve the original cabinet label from any damage.

To prevent runs, the surfaces will be turned horizontal for the heavier spraying that follows...

Along with more elbow grease and correction of fine detail, three flatted coats of high build have gone on. No more grain pits! However the appearance is still wrong - the veneers are too light and the contrast between them is too great. This will be rectified during the next stage when the toner is applied. This will restore the general walnut 'glow' that the cabinet had before.

I always think it's a shame when restorers use materials such as clear Danish Oil on an old radio cabinet. Although the grain pattern is then well seen, the cabinet looks nothing like it did originally.

The toner goes on. It was mixed with a little high-build to give better control of the colour during application. At this stage the finish is still matt. This will be followed by clear buffer coat before being rubbed down ready to take the final layers of finish. The actually colour is not very well shown here because of the fluorescent lighting...

After the first top coat has gone on, it's time to attend to the edge surfaces, such as the screen rim and the edges of the front veneers that sweep round the top and front.

Here the screen rim is masked up ready. This will be finished in a very dark brown, like the plinth at the base of the cabinet. However, the requirement for the edges of the front veneers is different. Rather than being contrasting features, these must not stand out. So a medium brown will be used.

At this time other little touches are attended to, such as dressing the underneath and interior of the cabinet and oiling the castors.

 

The HMV transfer is added to the top and at last the cabinet is finished. It won't be polished for several more weeks, until after the set's internals has been restored.

Here's the speaker and socket panel after being cleaned up. This is a rare and valuable set so will be a sensitive restoration. It's very important to preserve originality.

The wires' sleeves have been cleaned up so their bright colours can once again be seen and they have been gently conditioned by rubbing in Waxoyl. They should now be good for another 75 years... at least.

Here's the main deck. I always take copious digital close-up photos - about ten times as many that appear here - as I go. This way, I finish up with what is in effect an in-depth illustrated guide that records the dismantling. This is a great help later when everything goes back together.

I'm also keeping all the many small parts and their fasteners in individually labelled polythene bags. So, on reassembly the right fasteners will be matched with the right parts.

First I remove the band indicator lever mechanism and the dial. Dials are always removed early on and put away in a very safe place, well away from the rest of the action. Break the dial, and you can lose the whole job!

Here we see the light-absorbing card behind the dial is in poor condition. Somebody's been here before! This later will be re-flocked.

This is a general view of the underneath, once the screening can covering the RF and oscillator sections has been removed. It doesn't look too bad on this tiny picture but in fact the set has had a lot of previous service attention. Some attempt has already been made to make the replaced components look 'vintage' but in general there's too much 'new' stuff tacked on.

My task will be to return this to the closest I can manage to its original 1938/9 appearance. Some of this can be gleaned from studying the manual but I am now issuing an appeal... has anyone any pictures of the underneath of an unrestored HMV 907 chassis I can work from?

 

There was orginally a capacitor block at the rear of the main chassis. This was replaced around 60 years ago with an ugly stack of cardboard-cased electrolytics, which in turn had been disconnected by the previous operator and replaced with modern capacitors underneath.

I now am seeking to make up a new 'block' that looks more like the pre-war original. Here are some of the parts. The actual capacitors to hide inside it will be ordered after the Bank Holiday on Tuesday.

The story continues... click here...

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