Author Topic: Dial for old scales  (Read 3321 times)

Offline RussellT

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Dial for old scales
« on: March 23, 2023, 01:23:13 PM »
I've been restoring some old scales that came from my mother-in-laws shed. They were rather rusty so they've been dismantled, de-rusted, re-assembled, and painted in close to original colours.

 


All I have to do now is make a legible dial, which the original isn't.

 



I have redrawn the dial using a scan of the original to trace over.



 My original idea was to get someone to cut this out in vinyl for me and then use that to etch a brass dial.  However, after having redrawn the dial I think some of the detail is too fine for a vinyl cutter so I am wondering what to do.

I've thought of a number of options:

Print it on paper and cut an acrylic face to go over it.
Get it printed on sticky vinyl and stick it to the old face.
Get it laser engraved on brass deep enough to add paint and then clean up the brass leaving the markings visible.

I have no experience with laser engraving or cutting so I've no idea if the last option is even feasible, where to go or how much it would cost.

Does anyone have any other ideas, or advice on any of these?

Russell
Common sense is unfortunately not as common as its name suggests.

Offline awemawson

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Re: Dial for old scales
« Reply #1 on: March 23, 2023, 02:11:00 PM »
Think of it as a printed circuit board. Photo print it onto transparent sheet, apply photo-resist to a nice clean brass disk and expose it through the transparency.

Then etch the brass disc - you may want to make a negative version of your artwork.
Andrew Mawson
East Sussex

Offline philf

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Re: Dial for old scales
« Reply #2 on: March 23, 2023, 02:13:46 PM »
Russell,

I printed mine on card, cut round the outside, cut a bigger centre hole, encapsulated it and then trimmed around the outside and punched a centre hole so that it was completely sealed against moisture. I then stuck that to the old dial.

I wasn't bothered about it looking authentic - and I drew a scale calibrated in kgs.

Why have you missed out SALTER above HOUSEHOLD SCALE?

Phil.
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Offline russ57

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Re: Dial for old scales
« Reply #3 on: March 23, 2023, 07:07:13 PM »
what is the original?

Offline SwarfnStuff

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Re: Dial for old scales
« Reply #4 on: March 24, 2023, 01:46:49 AM »
Hi Russ,
     Perhaps you simply missed the brand "SALTER" on the original brass face you put a scan of in you post?
John B
Converting good metal into swarf sometimes ending up with something useful. ;-)

Offline RussellT

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Re: Dial for old scales
« Reply #5 on: March 24, 2023, 06:54:47 AM »
Phil, John - SALTER got left behind while I was moving it all to the middle of the page - thanks for pointing it out - I'd have been annoyed if I hadn't noticed it before I'd finished.

Phil, I could do something like yours - but I'm trying to make it fancy.  I have thought about doing a metric dial on the back of the imperial one.  Interestingly I found a picture of an original metric scale which was calibrated to 15 kilos (about 33 pounds) - I think they would just have adjusted the bar that goes through the spring to make the spring shorter.

Russ, the original was white paint on tin plate, with the design printed or stencilled on.

Andrew, that is a very good idea.  I had actually thought of that but dismissed it because I thought it would be difficult to get a printout without pinholes in the large white areas, but you prompted me to look again, and I discovered negative photoresist.  I've never done circuit boards like that - I generally use press'n'peel.  I will investigate further.

Russell
Common sense is unfortunately not as common as its name suggests.