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Old 8th Apr 2020, 3:40 pm   #1
Dickie
Octode
 
Join Date: Sep 2004
Location: St. Albans, Hertfordshire, UK.
Posts: 1,477
Default BC1792 "Stork" Loudspeaker restoration

This project has been on the to-do list for a very long time. Indeed, my records show I purchased this loudspeaker at Harpenden in June 1992, and since then it has sat on a top shelf gathering dust, and without the help from forum members that’s where it would have stayed. As you might be able to see from the “before” pictures it was in a fairly rough condition. The speaker fabric, although original, had shrunk and come away from the baffle board, leaving an untidy gap on one side. It had originally been glued on, and the glue had hardened and crinkled up the fabric. The dark oak stained cabinet had various deep scratches and bits of the veneer on the baffle board had been broken off.

Perhaps the biggest problem was a lot of missing wood beading around the edges. Way back when I bought it I can remember looking around for some replacements and came across a John Boddy timber merchant who had it listed in their catalogue. Fast forward 28 years and of course they no longer have a catalogue, let alone stock it. So the first step was an appeal on this forum for anyone who had any. Many thanks to “David G4EBT” for pointing me in the direction of Gary Tempest (not on this forum) who had some spare lengths following his own restoration (BVWS bulletin spring 2012) He promptly sent me his stock FOC and appointed me the keeper of the parts. Many thanks to Gary as well. So if anyone needs some bits of beading I can probably help!

Before doing anything I might regret I investigated things to see how far I would have to go and how much I could keep original. These loudspeakers don’t come up very often but neither are they very scarce, so I decided I would do whatever it needed to make it look presentable. The drive motor and paper cone came out easily and were put to one side. I gave the woodwork a good clean and a gentle rub down with steel wool. I then tried to touch up the scratches with various shades of woodstain but clearly my skill level wasn’t up to it and the scratches remained prominent. Getting the colour right is not too difficult but making the surface level and texture seamless is another matter. So I decided it had to be a full strip and refinish job. Turning my attention to the loudspeaker fabric I managed to remove it from the cabinet without further distress. As mentioned previously, where it had been glued to the baffle it had gone hard and crinkled. There then followed successively more aggressive attempts at cleaning it up. Following several hours soak in warm water a lot of very slimy stuff came off but when dried there was still a lot remaining in the weave and it was not a lot better. So we needed new material as well.
There then followed applications of paint stripper, white spirit, and sandpaper to the woodwork. Getting the old finish out of all the mouldings with a toothbrush and subsequent cleaning out was somewhat tedious. Having removed all the old finish I could see that although the sides, top, base, and mouldings were all mahogany, the fretwork baffle was some nondescript light coloured plywood. Maybe that was why it had all been originally stained down to a very dark oak colour. “Radio Radio” lists these as having been available in oak or mahogany, though I have never seen the latter. Either way, since dark oak is not my favourite and I had some mahogany stain, I decided to change its colour.

The next step was to repair the damage. Finding some thin veneer to repair the fretwork was surprisingly easily. The missing beading was then carefully glued on. The finishing process involved a couple of coats of woodstain (yes I know the can says only apply one coat), and then numerous layers of French polish. After a week or so to let the polish harden, the gloss was dulled down with steel wool and then a couple of coats of beeswax applied to finish it off.

I had by now visited all the local haberdashers and chosen a suitable replacement fabric. I had read Gary Tempest’s restoration article and from his description of gluing the fabric in the right place and stretching it at the same time sounded quite difficult and high-stress. So to get around that, I made a thin picture frame and stretched the fabric around it to start with. I then applied a layer of Copydex to the baffle, waited for it to dry a bit, and then put the picture frame in and pushed hard. After waiting for the glue to dry the picture frame was then removed leaving the fabric nice and tight.


To finish it off the cone and motor unit were replaced and the back screwed on with new screws. The old loudspeaker fabric was put in a bag and taped to the inside, out of the way. And just to finish, it does sound better than a horn ‘speaker’, but not a lot.
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Regards,

Richard, BVWS member
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