DIY glass diaphragms on a budget

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Ahmed
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DIY glass diaphragms on a budget

Post by Ahmed »

Can you cut your own glass diaphragms?

After a bit of tinkering, I'm happy to report yes you can!

It's a fairly simple process and doesn't require expensive kit, but will require practice to get the feel of it and a ton of patience (be prepared for a few failed attempts before you get it)

Ingredients:
1- Glass sheets; cheapo phone screen protectors work beautifully. They're between 0.2-0.3mm thick (4 for £1 on eBay)
2- Scribing tool (also cheapo off eBay)
3- Compass and paper
4- 250 grit sandpaper

Method:
1- Make a template of the diaphragm size you need on paper using the compass. Cut it out.
2- Stick the template on top of the glass (I use PVA glue so I can remove with water later)
3- With the scribing tool trace around the template. Don't apply too much pressure or it will crack.
4- Very gently apply pressure around the edge of the circle to snap off the glass. It helps to etch the glass around your circle into quadrants, so you're snapping off one quadrant at a time as you're working to free the diaphragm (imagine a sun rays sort of pattern)
5- If needed, you can use wet sandpaper to tidy up the edges or of it's a fraction of a mm too big (do wear a mask though as I've learned the hard way; lungs apparently don't like glass dust!).
6- et voila! Your glass diaphragm is ready!

Picture of the tools and finished product attached

The Pathé reproducer was the reason I wanted to try this, but I've also made one for an exhibition soundbox. This was attached to the needle bar with super glue which I've been able to undo easily using acetone.

Also made one to try on an Astra Electric soundbox (64mm diameter), but the stupid thing snapped as I was installing it. Will have a go at this one again when I have some time

Hope someone finds this helpful!
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Last edited by Ahmed on Fri Mar 26, 2021 5:49 pm, edited 1 time in total.

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poodling around
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Re: DIY glass diaphragms on a budget

Post by poodling around »

Ahmed wrote: Fri Mar 26, 2021 5:35 pm Can you cut your own glass diaphragms?

After a bit of tinkering, I'm happy to report yes you can!

It's a fairly simple process and doesn't require expensive kit, but will require a practice to get the feel of it and a ton of patience (be prepared for a few failed attempts before you get it)

Ingredients:
1- Glass sheets; cheapo phone screen protectors work beautifully. They're between 0.2-0.3mm thick (4 for £1 on eBay)
2- Scribing tool (also cheapo off eBay)
3- Compass and paper
4- 250 grit sandpaper

Method:
1- Make a template of the diaphragm size you need on paper using the compass. Cut it out.
2- Stick the template on top of the glass (I use PVA glue so I can remove with water later)
3- With the scribing tool trace around the template. Don't apply too much pressure or it will crack.
4- Very gently apply pressure around the edge of the circle to snap off the glass. It helps to etch the glass around your circle into quadrants, so you're snapping off one quadrant at a time as you're working to free the diaphragm (imagine a sun rays sort of pattern)
5- If needed, you can use wet sandpaper to tidy up the edges or of it's a fraction of a mm too big (do wear a mask though as I've learned the hard way; lungs apparently don't like glass dust!).
6- et voila! Your glass diaphragm is ready!

Picture of the tools and finished product attached

The Pathé reproducer was the reason I wanted to try this, but I've also made one for an exhibition soundbox. This was attached to the needle bar with super glue which I've been able to undo easily using acetone.

Also made one to try on an Astra Electric soundbox (64mm diameter), but the stupid thing snapped as I was installing it. Will have a go at this one again when I have some time

Hope someone finds this helpful!
Absolutely marvelous !

Can you please just confirm what you mean by 'Glass sheets; cheapo phone screen protectors work beautifully' - I thought phone screen protectors were thin, floppy, sticky plastic, not glass ?

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Ahmed
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Re: DIY glass diaphragms on a budget

Post by Ahmed »

@poodling around: Thank you :)

Screen protectors come in two varieties: thin plastic film or glass sheet. It's the latter I've been playing around with. They're often advertised as tampered glass, but the cheap ones are simply a standard piece of glass with a thin sheet of plastic to hold it together when/if it shatters

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poodling around
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Re: DIY glass diaphragms on a budget

Post by poodling around »

Ahmed wrote: Fri Mar 26, 2021 5:48 pm @poodling around: Thank you :)

Screen protectors come in two varieties: thin plastic film or glass sheet. It's the latter I've been playing around with. They're often advertised as tampered glass, but the cheap ones are simply a standard piece of glass with a thin sheet of plastic to hold it together when/if it shatters
Thank you for explaining Ahmed. I only visit the 21st century very occasionally ! :lol:

I usually use aluminium sheets but I will have a go with this glass next time. Great stuff !

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Re: DIY glass diaphragms on a budget

Post by Inigo »

Thanks for this lesson! But I don't know the tool you use for cutting the glass circle...
Inigo

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Re: DIY glass diaphragms on a budget

Post by Curt A »

Thanks for the idea... I need one.
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Ahmed
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Re: DIY glass diaphragms on a budget

Post by Ahmed »

Inigo wrote: Fri Mar 26, 2021 8:01 pm Thanks for this lesson! But I don't know the tool you use for cutting the glass circle...
It's a scribing tool with a carbide tip; the metal pen looking thing in the picture

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Re: DIY glass diaphragms on a budget

Post by Inigo »

Ah, OK. So you draw the circle perimeter, then the sun rays to help breaking the glass pieces around et voilá
Inigo

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Ahmed
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Re: DIY glass diaphragms on a budget

Post by Ahmed »

Inigo wrote: Sat Mar 27, 2021 4:37 am Ah, OK. So you draw the circle perimeter, then the sun rays to help breaking the glass pieces around et voilá
Exactly yeah. A tiny bit of pressure on the glass is all you need to snap off the excess pieces and release the circle

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jamiegramo
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Re: DIY glass diaphragms on a budget

Post by jamiegramo »

A good tip, thanks Ahmed. Some of the glass diaphragms I ordered from Germany got broken. So I will give it ago especially at the price. :D

I also have a small glass circle cutter I can try.

I found 4 x 0.2mm sheets at £1.49 ‘including’ postage. Here’s the link for anyone else in Britain, unless you found cheaper? :o

https://www.ebay.co.uk/itm/0-2MM-4x-Gen ... 2749.l2649

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