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 Dial glass replacement
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 Return to top of page · Post #: 1 · Written at 5:28:35 PM on 11 September 2012.
Maven's avatar
 Location: Canberra, ACT
 Member since 23 August 2012
 Member #: 1208
 Postcount: 584

As a new member, I'm surprised that this topic area has not been populated yet. There must be lots of lore and experience in cabinet restoration. Maybe it's scattered in other topics.

I inherited my Philips Radioplayer 123 with a broken dial glass. The rectangular sheet of 3/16th glass was very fragile and they easily break - say if the set is picked up the wrong way and a thumb puts pressure on the glass.

I tried superglue on the glass - hopeless. I tried laminating a second sheet of picture-frame glass behind the original - ugly.

Along the way I made things worse by trying to clean the glass before I realised that the graphics and lettering were in the form of a water-based decal. I lost some parts of the print when the surface was moistened.

Here's how I got a good-as-new tuning dial:

1. I re-assembled the broken glass on a flat-bed scanner and scanned a digital image of it.

2. Opened in PhotoShop, the image was too messy to clean up. However, it could be used as a template layer, as you might use with tracing paper.

3. In Adobe Illustrator I created a new image of the correct dimensions, with a TRANSPARENT background. I redrew the lines, curves and symbols using the scanned image as template. You could use any vector graphic program, including free open source ones. Paint programs will not get the same clean result with lines, curves and lettering that might have pixellated edges.

I found an Art Deco font very close to the original and matched all the state initials, knob descriptions and station IDs over the originals on the template layer.

When complete, I deleted the template layer.

I had to consult station lists to correct callsigns that had become unreadable on the original. I even copied the dial component number for authenticity, though it is obscured when the dial is in place.

The advantage of computer graphics is that you can work at a high magnification and make infinite corrections.

4. I found a matching digitised Philips logo online and added that, adjusting scale and colour to match original.

5. Once satisfied with the image content, I matched the colour to the original - a chocolate brown gave the best contrast to the cream speaker-cloth background..

6. My first idea was to reproduce the original "decal" and fix it to a new glass panel. I took the graphic file to a local sign-printing shop and got a couple printed up on plastic film with adhesive backing.

I found it impossible to get the "decal" straight and wrinkle-free on the glass - like putting the old-fashioned slippery car rego stickers on the windscreen, but much bigger and worse result.

7. I went back to the sign-shop and found they could print directly onto a sturdy polycarbonate sheet of the right dimensions. Of course, the image had to be printed in reverse, which is a snap with digital images.

If anything, the result is better than the original. The polycarbonate is not fragile, and the laser-printed lettering will better resist moisture and the light friction of the index.

Maven


 
 Return to top of page · Post #: 2 · Written at 5:55:23 PM on 11 September 2012.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 813

There are available laser printable water-slide decal sheets. Haven't tried them as my printer maker (Samsung) won't approve them, but this might be another method of reproducing dials.

However I recently bought a second identical printer for $50 on eBay just for the toners that went with it. Managed to get it going by cleaning the rollers. So will try this method one day, but probably to make replacement ARTS & P transfers.


 
 Return to top of page · Post #: 3 · Written at 7:15:56 PM on 11 September 2012.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5510

There are available laser printable water-slide decal sheets.

Where can we get these from?

However I recently bought a second identical printer for $50 on eBay just for the toners that went with it.

It's unfortunate (and not good for the planet) that printer manufacturers have no problem with printers being more of a consumable than a toner cartridge. It's the way it has always been though. Perplexed


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A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 4 · Written at 8:42:27 PM on 11 September 2012.
Maven's avatar
 Location: Canberra, ACT
 Member since 23 August 2012
 Member #: 1208
 Postcount: 584

Any stock to be used with a laser printer (heat-fused ink) has to have a high tolerance for heat. That's why photo printers are usually ink-jet (evaporative ink), incuding professional ones.

For laser-print dial decals, you'd need stock that was transparent and very thin as well as heat-tolerant.

I'd also be interested to know if it is available.

Maven


 
 Return to top of page · Post #: 5 · Written at 9:29:40 PM on 11 September 2012.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5510

I just had a thought that might scotch this whole idea. I am certain that printers cannot print anything in white and on most dial scales white is the only colour employed.

Can someone confirm either way?

If I am right then this problem won't apply where yellow and other colours are used.


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A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 6 · Written at 10:21:28 PM on 11 September 2012.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 813

Here is a selection on eBay

http://www.ebay.com.au/sch/ebayadvsearch/__laser-water-slide....

Think you are right about white - that would be a major limitation for Philips radios especially! Would need to come up with a white toner to replace the black. No idea if that is possible.


 
 Return to top of page · Post #: 7 · Written at 9:19:43 AM on 12 September 2012.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 813

This google search seems to indicate that white laser printing is possible. Also white sublimation printing.

http://www.google.com.au/search?hl=en&as_q=laser+printing....

Got a crook eye at the moment so can't read all this. Will have another look in a few weeks.


 
 Return to top of page · Post #: 8 · Written at 10:01:59 AM on 12 September 2012.
Maven's avatar
 Location: Canberra, ACT
 Member since 23 August 2012
 Member #: 1208
 Postcount: 584

It'll be interesting if someone can report experience with this method.

Investing in special white toner might be worth while for somebody with a lot of dials to print, or providing a service to others. Otherwise a very light yellow or cream might be effective and would use the standard colour inks, as long as the image data specifies 100% opacity. A light grey would probably exhibit lower opacity and hence lower visibility.

For one-off jobs, I think most people would find a professional job more economical - if I recall correctly, mine cost about $40 including the perspex/polycarbonate.

Also, RadioPlayers of my vintage (1950) use back-lit dials against a light-coloured cloth, so darker markings give better visibility.

To be exact, I believe that the original glass dial-plate, lit from the side, may have provided more refracted front-light than the polycarbonate sheet does onto the decal located on the rear face of the glass, so I rely more on the contrast between the backing cloth and the opacity of the lettering.

Maven


 
 Return to top of page · Post #: 9 · Written at 11:20:12 AM on 12 September 2012.
Gandhn's Gravatar
 Location: Windella, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 319

I have purchased the ink jet compatible transfer sheets from a model aircraft hobby shop in Newcastle, "Frontline Hobbies".
I didn't have a great deal of success with a dial, as the transfer adhesive was slightly cloudy on the glass. For putting a transfer onto a solid colour background it would be perfect.
Where I had a great success was doing an elliptical "Caution" transfer for the early Radiolettes. I photographed my least damaged transfer, then Photoshopped it to fill in the missing pieces. This transfer went onto the painted panel and looks perfect.
Harold


 
 Return to top of page · Post #: 10 · Written at 1:06:54 PM on 12 September 2012.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5510

I always remember old rego labels and NRMA member labels having that opaqueness to their clear edges. I am assuming the same issue applies with the current materials.


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A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 11 · Written at 3:24:40 PM on 12 September 2012.
STC830's Gravatar
 Location: NSW
 Member since 10 June 2010
 Member #: 681
 Postcount: 813

"Any stock to be used with a laser printer (heat-fused ink) has to have a high tolerance for heat. That's why photo printers are usually ink-jet (evaporative ink), including professional ones.

For laser-print dial decals, you'd need stock that was transparent and very thin as well as heat-tolerant."

If there is laser printer stock for the old overhead projectors (is anyone still using them?) then this might be suitable for some cases. Don't see why there wouldn't be - used to make overheads on a photocopier.

-------------

Wonder if some of the old dials were silk screen printed. If so this might be suitable for white only, but expensive I think.


 
 Return to top of page · Post #: 12 · Written at 5:40:23 PM on 12 September 2012.
Maven's avatar
 Location: Canberra, ACT
 Member since 23 August 2012
 Member #: 1208
 Postcount: 584

Officeworks have this product for overheads that they claim is suitable for "most" inkjet and laser printers.

http://www.officeworks.com.au/retail/products/Technology/Projectors/Overhead-Projectors/AC0025

I haven't tried that specific product, but in my experience it is more likely to be suitable for "some" lasers. Only experience would tell...

$52 for 25 chances to try it out....


Maven


 
 Return to top of page · Post #: 13 · Written at 11:21:38 AM on 14 September 2012.
Gandhn's Gravatar
 Location: Windella, NSW
 Member since 5 November 2010
 Member #: 770
 Postcount: 319

I have also tried the overhead projector film with an ink jet printer to reproduce a dial, but it suffered the same opaque background problem as the water based decal.
In a previous life, I have used a silk screen process and it would certainly be the best solution for dials of any colour. I guess it just depends on what you consider is an acceptable finish.
Harold


 
 Return to top of page · Post #: 14 · Written at 1:34:50 PM on 14 September 2012.
Maven's avatar
 Location: Canberra, ACT
 Member since 23 August 2012
 Member #: 1208
 Postcount: 584

Agree silk screen on glass would be the best result all around for transparent dial panels. What would be the cost, considering most restorers are doing a one-off job?

My professional ink-jet-on-perspex dial looks perfectly clear and you would think from the front that it was glass - except that it doesn't transmit as much light sideways, from the hidden 6v bulbs on either side, so you get a less even illumination than with glass.

I'm toying with the idea of putting modern LED striplights of some sort in behind the fascia, to illuminate the dial panel more evenly. The available 6v AC could drive them via a diode and current-limiting resistor - maybe even a low-profile dimming pot mounted on the back of the cabinet.

One incentive for this is that the replacement 6v bulbs available now are taller than the originals, so the filaments are too high for ideal dial illumination and I've had to recess the lamp mountings a little awkwardly to adjust the light source position.

Maven


 
 Return to top of page · Post #: 15 · Written at 2:28:26 PM on 14 September 2012.
Brad's avatar
 Administrator
 Location: Greenwich, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 5510

I'm toying with the idea of putting modern LED striplights of some sort in behind the fascia, to illuminate the dial panel more evenly...

There's a couple of things to remember with this. Firstly, you would need to obtain warm white LEDs otherwise the colour temperature would not be realistic. Secondly, some LED strips require regulation and/or drivers whereas others don't. Some experimentation may be required to achieve a desired effect.


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A valve a day keeps the transistor away...

 
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