Next Year's project

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jack
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#46 Re: Next Year's project

Post by jack »

Not daft. Bare-bones restoration is the way to go for this one.

You should also look at the British Vintage Wireless Society site - loads on useful information and contacts there - https://www.bvws.org.uk

The case can be repaired. There are several sites out there and loads of videos. Whatever you end up doing, the case will need a good wash with warm washing up liquid and a toothbrush/cotton buds etc. When finished repairing, polish with "Polishing Paste #5" from Greygate, which is what BT recommended for bakelite 'phones. Finish with a protective light coat of clear wax - Carnauba or the clear stuff used for antique wood furniture.

There are some coloured puttys that are excellent for repairing Bakelite and I know there is a black one. It's called "Milliput Superfine" and can be got on Amazon.

This is my dac90a case after repair and cleaning. I used Milliput - a mixture of brown and black to get the right look.
20120804_104156.jpg
Last edited by jack on Tue Nov 27, 2018 8:24 am, edited 1 time in total.
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Ray P
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#47 Re: Next Year's project

Post by Ray P »

Thanks Nick, I'm familiar with milliput having used it for model making but thought it was only available as grey/green stuff. I'll do some digging.

I've had a look at bakelite repair references and I think that with my one I will need to laminate epoxy/glass across the inside of the base to strengthen it because of all the cracks (you can't see all of them in the pictures. Because of my model making experience, this won't be a problem for me as I've done lots of carbon/epoxy lay-ups before.
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Ray P
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#48 Re: Next Year's project

Post by Ray P »

Nice job on your DAC90 BTW.
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jack
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#49 Re: Next Year's project

Post by jack »

Thanks. I have a row of DAC90As and DAC10s plus an extremely rare Ekco A22 to do when I return.

I've used the epoxy + FR4 strip trick myself several times - it works very well...

One reason for the wash & scrub on Bakelite is that most radios of that era tend to be coated with nicotine as everyone chain-smoked awful stuff like roll-ups or "Navy Cut" - aka, coffin nails.

This also affects internal components, so I tend to clean those too with IPA, methylated spirits or similar.

Small warning - the surface finish on Bakelite is quite thin as the "plastic" was bulked up with sawdust etc. If sanding down after filling/repairing, be very gentle else you'll lose the surface and end up with the rough core :) also, although wood is the most common filler, sometimes up to 5% brown asbestos was used, so watch that dust...

Some notes on how I stripped and cleaned my DAC90A are at https://www.vintage-radio.net/forum/sho ... hp?t=86584
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Mike H
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#50 Re: Next Year's project

Post by Mike H »

LOTS of rust!

Yep Nick's very encouraging, seems most case damage is the bottom and back edges? I'd wanna have a go. :thumbleft:
 
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Ray P
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#51 Re: Next Year's project

Post by Ray P »

Mike H wrote: Tue Nov 27, 2018 12:30 pm LOTS of rust!

Yep Nick's very encouraging, seems most case damage is the bottom and back edges? I'd wanna have a go. :thumbleft:
The rust will clean up OK, it's relatively superficial.

Decision made: I'm gonna give it a go and see what I can do. Lets say 'I accept the challenge'!
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Ray P
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#52 Re: Next Year's project

Post by Ray P »

I ordered some packs of black and terracotta milliput from Amazon today so will try to get the repairs to the bakelite underway over the Christmas break.

If i can get some heating into the garage temporarily I should be able to laminate some epoxy/glass across the inside face of the bottom of the enclosure too.

I'll open a new thread over at 'Everyone's Projects' to record future progress.
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jack
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#53 Re: Next Year's project

Post by jack »

TBH, you don't need to get too cute on this - the repairs are not structural.

I just use strips of FR4 and araldite...
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Ray P
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#54 Re: Next Year's project

Post by Ray P »

jack wrote: Sat Dec 01, 2018 6:15 pm TBH, you don't need to get too cute on this - the repairs are not structural.

I just use strips of FR4 and araldite...
It would be a good use for some laminating epoxy I have left from a few months ago and I have plenty of glass (and carbon) offcuts and all the tools so it would be rather nice add in a bit of structural strength given the number of cracks in the base. Might even be interesting to vacuum bag it.
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Mike H
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#55 Re: Next Year's project

Post by Mike H »

Wanna see that. :D
 
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