Perspex as dial glass replacement material

[Steve_P]

A lot of Transistor sets use perspex. I've never seen it on a valve set - but the problem is that plastic and perspex is likely to melt. The bulbs behind might melt or burn the plastic.

Just a thought.

Cheers,

Steve P.

[Robert Darwent]

I've never seen it on a valve set...

There are not a lot of mains only valve sets I agree, but in addition to the Ekco A22 which I mentioned earlier (the dial is not made of acetate or celluloid as is often quoted), what about such models as the Bush DAC70 that have dials more commonly seen on portables?

Turning to mains/battery or battery only valve sets, there are many that have perspex dials. Examples from sets that I own - Vidor Vanguard, Ever Ready Sky Emperor/Berec Commander, Philips Colette, etc.

Regarding heat produced from bulbs. Obviously that depends upon the wattage of the bulb and how well designed the set was in the first place as to whether it is an issue or not.

Going back to the two mains only sets I gave as examples - I've never heard of a problem with a heat damaged dial in the Ekco A22, but with the Bush DAC70 it is a very common problem.

Regards

[60 oldjohn]

I have a Cossor 464 the original Celuloide cover had shrunk and I made one out of perspex. My mistake was to make it a perfect fit, not tight but "snug" and held in place with Areldite. Ten years on and Hairline cracks are apearing at the corners of the aperture in the Bakerlte. The perspex expands at a different rate to the Bakerlite. I dont use the set so no heat from bulbs, just natural temperature vairiations. I think I should have made it smaller and fixed it with clear Sillicone.
John.

[Yorkie]

I think that it would be nigh on impossible to do this well in glass without breaking it.

Regards

Rob

It would for you or I Rob, but not for a glazier. It's just an oblong piece of glass with two holes - presumably about 10 - 15mm drilled in it. (Whatever the dial is to be made of, presumably you intend to make and apply a waterslide transfer to it on the underside). If you've got an old cracked or broken dial as a pattern for the size and gauge, it would be worth taking it to a local glazier for a price. They do far more demanding things than that - drilling holes in large mirrors, plate glass shop windows and display cabinets, and so forth.

[Bushbaby]

Hi David,
Thanks for the advice. I do indeed have the original glass which is broken in 2 pieces. I've also a smashed but reglued glass to a Pye PE80 too,

I always thought that this would be far too expensive to pursue through this route.

Thanks

Rob

[Radio Fixer]

I think David is right there, even small outfits drill holes and the cutting out is no problem.

For me I had to go to a specialist (Basildon Glass) who have CNC equip. THe single hole, around 12 mm was no problem but I needed a 45 deg. polished bezel, for a light guide, to illuminate the silk screening from behind. They charged me £16 each for 10 off.

Gary