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VINTAGE RADIO By JOHN HILL Timber cabinets are a lot of work Last month, I divided radio cabinets into two categories - synthetic materials (plastic and Bakelite) and natural materials such as timber. This month's topic is the restoration of timber cabinets. The restoration of a timber cabinet is a far more daunting task than the restoration of a Bakelite (or plastic) cabinet and would be at least 10 times more time consuming. To do a tradesman-like job of a large console type cabinet can easily consume 20 or more hours of time. If one was to charge at plumber's rates for that amount of time, the real value of such a restoration soon becomes apparent. In time alone, a well-restored radio with a timber cabinet must be valued at hundreds of dollars. Whether anyone would actually pay that amount is entirely another matter. Enough of this hypothetical speculation. Let's get on with the restoration of a timber cabinet. Strip down A complete strip-down of unnecessary bits and pieces is a good starting point. Everything must be stripped from the cabinet, leaving it a completely bare shell and nothing else. A thorough clean-up is next and the cabinet should be brushed down, both inside and out, to remove cobwebs, dust, fluff and other rubbish that has attached An old flat file makes a handy varnish scraper but care must be taken not to dig the corners into the timber. If the lacquer is difficult to scrape off, you may have to resort to using paint stripper. 16 SILICON CHIP itself to the woodwork. A good blast of compressed air helps to finish off this operation. Many old radio cabinets were made back in the days when animal glues were in common use. These natural glues were quite effective but they weren't waterproof and 40-50 years or more is a long time for any glue to hold things together. As a result, many of the glued joints may have come unstuck and will require re-gluing. Some cabinets are better than others as far as loose joints are concerned. In odd cases the cabinet frame is strong and rigid and, if it has always been indoors, it may not require much attention at all. On the other hand, if a relatively weak cabinet has spent the past 15-20 years under the leaky iron roof of a backyard shed, then there is a good chance of it being in fairly poor condition. Such a cabinet will require extensive re-gluing and the odd nail or two to tighten up the frame. The first major task (and undoubtedly the worst aspect of restoring a timber cabinet) is to remove all the old varnish and strip the outside surface back to bare wood. On a large console type cabinet this can amount to anything from five to eight hours work with every minute of that time being totally boring to say the least. With really ancient radio cabinets, removing the old lacquer is not that difficult because it becomes crazed and loses its grip on the surface of the wood. When this is the case, the old varnish scrapes off with ease. Although there are many commercial paint scrapers available, it A nicely restored timber radio cabinet is a joy to behold. This old HMV has a pleasant blend of several different timbers. At least 8-hours of work was required to restore this console cabinet. The old lacquer had to be scraped back to bare wood. sitting on the cabinet and working on it in every imaginable position which could spring a joint open. Cabinet repairs Paint stripper, woodstop putty and wood stain are all part of the act when preparing a timber cabinet for respraying. is perhaps better to make one from an old flat file. If the end is ground off at a 90° cutting angle, the homemade scraper works quite well. What's more, it is easily resharpened and will just about last forever. Not all exterior surfaces are easily removed. Some of the timber cabinets from the late 1940s and early 1950s still have their lacquer well attached and it can be extremely difficult to scrape off. These cabinets require a more drastic means of attack and paint stripper is usually quite effective. Even then, removing the old varnish can be a long and tedious job. It can also be a bit messy. Anyway, like it or not, if one is to restore a timber radio cabinet, then all the original surface treatment must be removed by some means or other. And no matter how it is done, it will involve a good many hours of work. Once all the lacquer has been removed, it's a good idea to recheck for loose joints again. The scraping operation often involves One disadvantage with wood is that it dents easily and these dents are the next problem to overcome. Applying steam (either by a boiling kettle or a hot iron placed on a damp cloth) will help to lessen the dents. Steaming makes the wood fibres swell, thus reducing the depth of the depression. However, this operation is not always successful due to the size of some of the dents. The majority of timber cabinets, with the exception of very early radios, are of the wood veneer type. In other words, the cabinet construction is basically of cheap plywood which has a thin veneer of attractive wood on the outside. Occasionally, the veneer develops blisters and these must be properly treated before sanding the cabinet down. Blisters and other raised portions of the veneer are repaired by first cutting a slit into the trouble spot in order to get some glue inside the blister. Once this has been done, the blister must be clamped flat and held that way for 24 hours untii the MARCH 1989 17 When sanding, the aim is to remove all imperfections without going through the thin skin of the veneer. There are times when this cannot be done and it is better to "bog up" a deep groove or depression with filler rather than risk ruining the cabinet with too much sanding. Sanding should be done in the direction of the grain with a relatively fine grade of paper. Interior finish Open joints and split timbers must be re-glued before the cabinet is sanded down. You will also have to repair any blisters that have developed, while cracks and chips can be repaired using woodstop putty. glue has thoroughly dried. A webbing clamp is a very useful gadget when doing those tedious repairs. Any separation of the plywood will also require re-gluing and clamping. Ply separations are usually caused by moisture which softens the glue and allows the layers of ply to part company. Another problem with timber cabinets is chipping of the veneer at the edges. These hollows can be repaired by replacing them with a suitable patch of similar veneer or by filling in the gaps with a woodstop putty of the appropriate shade to match the timber. When all these little jobs have been done, it's time to start sanding down the cabinet with sandpaper. Sanding must be done carefully because the thickness of the veneer is considerably less than 1mm, which leaves only a small margin for error. A coarse grade of sandpaper is not advisable as it can rip through the veneer in a couple of heavy rubs. An air compressor is a very useful accessory for the vintage radio enthusiast. A blast of compressed air is often useful when cleaning up the cabinet and it can also be used drive a spray gun. 18 SILICON CHIP The insides of timber radio cabinets are usually quite roughly finished and they are either painted black or given a quick coat of whatever went on the outside. Personally, I prefer to touch up the inside of a cabinet before finishing the outside, although there is no reason why the reverse procedure cannot be adopted. If the cabinet is black inside (as a good many are), a suitable treatment is a full gloss black enamel paint diluted about 50:50 with mineral turps. The thinned down paint can be applied with a brush and will soak into the wood so readily that it leaves a matt finish. Cabinets that are lacquered inside can be given a one coat touchup with low gloss varnish. Outside finish At this stage, some cabinets will be ready for a final finish but many others will require further preparation. For example, some cabinet frames are made of very lightcoloured timbers which require staining to a darker shade so as to match the veneer of the plywood. This must be done before the lacquer is applied otherwise the contrast between the near white pine frame and the dark walnut veneer is just too great. Other cabinets will require some external painting of trim areas before the clear lacquer is administered. It seems logical to complete these trim areas first and then cover the paintwork with the clear lacquer. The paintwork may require several coats and will need 24 hours drying time before the final top coating. Those highlighted trim spots are usually either black or dark brown and can give the cabinet quite a lift Vintage Radio Kits & Parts ORPHEUS *RADIO* A small spray gun is the only way to go when restoring timber radio cabinets. This touch up spray gun cost around $75. A fully restored console cabinet. A lot of work was involved in this restoration hut the results made the effort well worthwhile. as far as appearance goes. The paintwork invariably matches the colour of the knobs and the dial escutcheon. It takes time and a great deal of care to neatly cover these painted areas and a sloppy job will spoil the overall effect of the restoration. When applying the clear lacquer (three or four coats if a really good deep finish is required), a small spray painting outfit is the only way to go. The job can be done with a brush but generally speaking, brushes produce a second rate job. To my knowledge, radio cabinets were never French polished. Clear lacquers such as "Estapol" seem to be as good as any to use and one must choose between gloss and satin (semi-gloss) or mix a bit of each for a surface lustre somewhere in-between. This bit-ofeach treatment is particularly good as a full gloss finish on an antique radio often looks out of place. Antiques should have a subdued appearance and a brilliant high-gloss finish seems inappropriate to me. Speaker fabrics, as mentioned last month, also play a big part in the restoration of a timber radio cabinet. Rather than repeat myself, I will refer readers to last month's column for details on this aspect of cabinet restoration. To sum up, restoring a timber radio cabinet is a major job that will test the skill and enthusiasm of any vintage collector. If he can come at this task time and time again, he is either truly insane or really keen on his hobby. Perhaps a bit of both? ~ Suppliers of • • • • • VALVES RADIO KITS CAPACllORS RESISlORS BOOKS, ETC. 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