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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE! |
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12th Dec 2011, 7:09 pm | #1 |
Dekatron
Join Date: Mar 2008
Location: Worthing, West Sussex, UK
Posts: 5,185
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Another Bush Reborn
I did this little set as a test to see how long it would take to fully restore an average DAC90A to a high standard, as I have been asked to restore a couple.
This particular set is a later version, sporting a gold dial and perspex backed knobs. The date on the smoothing cap is august 1956, amazingly, the DAC90A stayed in production until late 1959, being the most successful set Bush ever produced. After a quick inspection I powered it up slowly via my variac and it crackled into life. Shortly after, I could hear the mains filter cap fizzing away, so switched it off quick! On removal of the chassis, it was clear that no repairs had ever been done since new, a point to note here, the knobs are usually held on with grub screws accessed via two holes underneath the set, in this case, the knobs are of the pull off type. After removing the dust with a paintbrush and vacuum, the chassis was cleaned using a rag wetted with WD40. The dial diffuser was removed and the light tray was given a good clean. The spewed mess that was the mains filter cap was removed, then time to tackle the re-capping. These little sets are a joy to work on, all 10 waxies are easily accessed, most being on a tagstrip. I replaced all caps under the chassis with nice new ones, the resistors were checked at this point and all were within spec. I then replaced the tone correction cap on top of the output transformer and replaced the mains filter cap with an X2 type, modifying the original clamp to hold the new cap in place. All the valves had their pins cleaned, and the holders were given a dose of Servisol, along with the wavechange switch and volume pot. I fitted new dial bulbs and refitted the diffuser. Then a drip of oil on the tuning pulleys, time to power up the chassis. I ran it up via the variac, and all was well, this set really can rattle windows! Leaving the chassis merrily playing away, I turned my attention to the cabinet. This was just a bit grubby, but no cracks or chips, it was cleaned using Fairy Liquid and cold water. It cleaned up well despite all the little paint spots that were gently scraped away using a fingernail. The cabinet was left to dry, so on to the speaker grille. I have found Flash kitchen spray works wonder on these, gently scrubbed with an old toothbrush. The knobs were cleaned with Fairy Liquid and cold water, the dial glass was very carefully cleaned, as the markings on the underside can easily come away. The cabinet was then polished up with T-cut, then polished using neutral wax polish, the set was then reassembled, the knobs fitted and given a final polish with a soft duster. Well, I can report that the total time taken was just under five hours from start to finish, and around £6 in new parts. It really performs well, with plenty of volume, no hum at all, and the speaker on this set is perfect. The set really looks as good as it sounds, the only downside is some staining of the bottom of the dial but it is 55 years old! Mark |
12th Dec 2011, 7:11 pm | #2 |
Dekatron
Join Date: Mar 2008
Location: Worthing, West Sussex, UK
Posts: 5,185
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Re: Another Bush Reborn
And the finished set....
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12th Dec 2011, 7:27 pm | #3 |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,820
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Re: Another Bush Reborn
Great work there
Certainly easier than the DAC90, I find those a bit fiddly with the tag strip mounted vertically. I think I spent something daft like 2 months on my DAC90! it was a mess though I've set myself a task for the winter to rebuild a DAC90a from spare parts! Started with an empty case, then got the remains of a chassis thats been butchered for spares! The case looks good so far, and I threw the most disgusting chassis in history straight into the ultrasonic cleaner. Doesn't look as good as yours yet though! regards, Lloyd. |
12th Dec 2011, 8:19 pm | #4 |
Retired Dormant Member
Join Date: Jan 2007
Location: Westbury, Wiltshire, UK.
Posts: 2,451
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Re: Another Bush Reborn
That has come up well. Nice one
I don't know why but one of my DAC90As has a silverish loudspeaker grill rather than the usual gold. I can't see any damage to the coating so assume it is a variant but it is the only one I have ever seen. |
12th Dec 2011, 8:57 pm | #5 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,935
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Re: Another Bush Reborn
Mint! Gerry Wells used claim 15 minutes to sort.
David |
12th Dec 2011, 9:44 pm | #6 |
Retired Dormant Member
Join Date: Apr 2008
Location: Warrington, Cheshire, UK.
Posts: 421
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Re: Another Bush Reborn
Nice one Mark, well done.
cheers Mark |
12th Dec 2011, 9:47 pm | #7 | ||
Dekatron
Join Date: Mar 2008
Location: Worthing, West Sussex, UK
Posts: 5,185
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Re: Another Bush Reborn
I am quite pleased with this set, it is still belting out 'gold' as I type. I wish all restorations were this easy
Quote:
Quote:
But I feel a custom paint job is in the offing...... Is yours really as bad as this? Mark |
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13th Dec 2011, 12:11 am | #8 |
Retired Dormant Member
Join Date: Dec 2009
Location: Milton Keynes
Posts: 144
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Re: Another Bush Reborn
What a fantastic restoration I'm totally impressed!
I rarely restore the chassis cosmetically, although I'll happily spend ages on painting, polishing, cleaning and repairing the case etc. Perhaps on my next restoration I'll have a go at the chassis too. Rob |
13th Dec 2011, 11:54 am | #9 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,935
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Re: Another Bush Reborn
Hi Mark,no i couldnt change more than halve the caps either in that time!
David |
13th Dec 2011, 12:04 pm | #10 |
Heptode
Join Date: Apr 2008
Location: Eastbourne, East Sussex, UK.
Posts: 671
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Re: Another Bush Reborn
Nice, that's come up well and should give enjoyment for many years to come!
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13th Dec 2011, 12:55 pm | #11 |
Octode
Join Date: Sep 2009
Location: Bath, Somerset, UK.
Posts: 1,033
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Re: Another Bush Reborn
A very tidy restoration
I have two DAC90a (s) - one is SO LOUD it is shocking. The other is in terrible electrical condition and rather quiet. It is odd how they vary so much. SEAN
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There are only 10 types of people, those who understand the binary system, and those who don't. |
13th Dec 2011, 9:00 pm | #12 |
Octode
Join Date: Mar 2011
Location: Sheffield, South Yorkshire, UK.
Posts: 1,453
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Re: Another Bush Reborn
My first successful restoration was a brown DAC90a and agree that they are fantastic sets both to work on and in terms of performance.
I too have a desire for a smashed one that can be 'Customised.' - Joe |
13th Dec 2011, 10:39 pm | #13 |
Dekatron
Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,748
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Re: Another Bush Reborn
Lovely job, Mark. I'm also impressed with how well the chassis looks after the WD40-and-rag treatment. Well done!
I haven't restored one of these but I did something close, an AC91 which has an autotransformer and short wave coverage. It's incredibly sensitive and sounds very nice. Pity the "Bush" brand has become so devalued, these were really high quality sets.
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Phil Optimist [n]: One who is not in possession of the full facts |
14th Dec 2011, 10:22 am | #14 | ||
Dekatron
Join Date: Mar 2008
Location: Worthing, West Sussex, UK
Posts: 5,185
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Re: Another Bush Reborn
Quote:
I agree, they do vary in performance, i have five, this one has loads of volume & the best looking UL41 i have seen, it looks as new, none of the usual brown stains on the glass, i don't think this set has seen much use, it certainly shows that a full recapping works wonders. Quote:
Hopefully, there will be another success story soon, as i have a 1947 dac90 on the to do list. Mark |
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14th Dec 2011, 4:06 pm | #15 |
Hexode
Join Date: Dec 2009
Location: Tamworth, Staffordshire, UK.
Posts: 320
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Re: Another Bush Reborn
Hello Mark, looks a cracking set now, wish I could get all my chassis looking like that.
Brilliant, Well Done.
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Cheers Paul. |
14th Dec 2011, 7:12 pm | #16 | |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,820
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Re: Another Bush Reborn
Quote:
So far I'm short of an output tx, speaker, aerial coils, dial bulbs, wavechange switch, back cover, dial and knobs Not too much to find! I do have a spare dial from a DAC90, which I could use, and I'm sure I could copy the knobs in resin or something. I'll have to find a picture of the chassis before I cleaned it, it really was yuck! Good luck with the DAC90, the one I recently finished sounds great, they kick out far too much heat though. Regards, Lloyd. |
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