Sourcing/making odd vintage acrylic crystal

[Chopin]

I have a lovely vintage 70s watch that I got without a crystal and I'm having a hard time finding a replacement. The genuine one is most likely not to be found so I'm looking for a generic replacement.

If someone could recommend a couple of stores that have plenty of crystals around I would appreciate it. So far I've searched the entire Cousins website and I couldn't find the dimensions that I need which are, sadly, pretty weird and unusual.

The crystal slot measures 31,013mm x 27,65mm. Thickness is 1mm and the slot is standard "L" shaped. The case is straight, not curved, and by looking at a few somewhat similar models the glass was flat as well.

I'm guessing that my best bet would be to make one on my own. The problem is that although I know that I can pull it off (and the sheets are cheap) I lack the materials so it would take me a lot of time and effort to do it... But I might end up doing it.

Does anyone have any suggestions or recommendations ? I also thought about buying a slightly larger glass (either in width or length) and just cut it down on one side but the shape itself is not rectangular but bale/barrel shaped so I guess that that might not work either...

Also, is it safe to say that if I were to get a slightly larger crystal and cut it to size, it wouldn't exactly work because most seem to be raised a bit and I would cut it on one side and I'd just remove the raised inner edge that it has ?

Edited May 14, 2018 by Chopin

[manodeoro]

With a Dremel and an inking-pad you can make your own plexi

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[Chopin]

I know but I don't even have a dremel...

What is an inking pad ?

[oldhippy]

You can send it away and have one made.

[Chopin]

Yeah that's a solution as well. I don't know anyone that makes them and I don't know how much it would cost... Any recommendations ? Preferably here in Europe.

[manodeoro]

1 hour ago, Chopin said:

I know but I don't even have a dremel...

What is an inking pad ?

inking pad (pic below) ...

 

the process :

1 -  get a  square of plexi  just a little larger than the one you nedd

2 - stamp your watch case on the inking pad then on the plexi

3 - use a dremel to grind the plexi to the right dimensions (you can also grind a bevel all around the upper side of the plexi)

4 - polish the sides

5 - press it in the watch case (you can use Hypo cement or UV glue if needed) 

but without a dremel you cant do all that  

So you should follow oldhippy's advice and have a custom crystal/plexi made

[manodeoro]

21 minutes ago, Chopin said:

Yeah that's a solution as well. I don't know anyone that makes them and I don't know how much it would cost... Any recommendations ? Preferably here in Europe.

Where in EU ?

Search for a society that can laser cut on plexi.

If you speak French you can ask those guys : [email protected]  

If you dont speak French I can help you 

Edited May 15, 2018 by manodeoro

[jdm]

2 hours ago, Chopin said:

I know but I don't even have a dremel...

You should really, really get one. Non-branded tools start at $10 and yes they work pretty much the same. Having a custom crystal cut will set you back a minimum 100 EUR I think. 

[Chopin]

The inking pad thing sounds great. Thanks. I guess I'll try that at some point... Think I've seen cheap dremels... They might do the job...

THe laser cutting thing would be the easiest but in the end it's too complicated. Would have to measure the case exactly somehow, etc. Might end up quite pricey as well.

Edited May 15, 2018 by Chopin

[manodeoro]

You should really, really get one. Non-branded tools start at $10 and yes they work pretty much the same.

Força little more (40€ in EU) you can get one with a cariable speed dimmer.
With mine, plus a cheap wolfcraft drill stand (70€ on Amazon) I even drill lugs and crown tube holes.

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[manodeoro]

The inking pad thing sounds great. Thanks. I guess I'll try that at some point... Think I've seen cheap dremels... They might do the job...

If you need any advice about how to use you dremel-like just feel free to ask.
Where are you in EU ? (I'm in France)

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[manodeoro]

21 minutes ago, manodeoro said:

Força little more (40€ in EU) you can get one with a cariable speed dimmer.
With mine, plus a cheap wolfcraft drill stand (70€ on Amazon) I even drill lugs and crown tube holes.

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Sorry ... tipping problems

For a little more (40€ in EU) you can get one with a variable speed dimmer.

It's really important because you can set the speed depending on the material you grind/drill/cut.

e.g. to grind plexi you should set a very low speed ... if not the plexi will heat and could get tarnished

same when you drill thin holes in stainless steel ... if you drill too fast the drilling bit could  get too hot, expand, get stucked in the hole you drill and break  so you have to drill at low speed and use some cutting oil (a bunch of cutting oil to be true)

Edited May 15, 2018 by manodeoro

[Chopin]

I am from Romania.

I'll have to order a new crystal for a watch from Cousins so when I do that I'll get some acrylic sheets as well and see where I go from there.

Thanks for the dremel tips. So ideally one with multiple speeds. I can get one here locally just don't know what the prices are. Going to look into it.

I'd probably use a dremel for case polishing and crystal polishing as well so it would be a good investment. Are the tips universal ? I've seen a lot of affordable ones from China. They come in sets and they offer a whole variety of stuff.

Edited May 15, 2018 by Chopin

[manodeoro]

You'll have to polish the sides after grinding so you'd better grind just a little larger (1/4mm) than the size you need.

Then you use water sandpaper (the one car painters use) ... 1200 grade then 2400 grade or more

https://www.ebay.co.uk/itm/Wet-and-Dry-Sandpaper-600-3000-grit-STARCKE-Abrasive-Waterproof-Paper-Sheets/302146134759?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D50546%26meid%3D4d785341e31442da9ff105aa9dfb1d05%26pid%3D100623%26rk%3D3%26rkt%3D6%26sd%3D161334194814%26itm%3D302146134759&_trksid=p2047675.c100623.m-1

When your plexi is perfectly sized you finish with some polish paste : https://www.plastiquesurmesure.com/pate-a-polir-marron-113gz.html

I cant guarantee you'll succeed but that's the way I do ... with good results

Edited May 15, 2018 by manodeoro

[manodeoro]

30 minutes ago, Chopin said:

I am from Romania.

I'll have to order a new crystal for a watch from Cousins so when I do that I'll get some acrylic sheets as well and see where I go from there.

Thanks for the dremel tips. So ideally one with multiple speeds. I can get one here locally just don't know what the prices are. Going to look into it.

Depending on where you live in Romania you could go to LEROY MERLIN and see if they sell the tool below (DEXTER dremel-like - only 35€ in France).

That's the one I have and it proved to be a really good tool.

 

Edited May 15, 2018 by manodeoro

[Chopin]

Yeah I think I can find something like that. Did it come with the entire set of bits ? That's very nice.

PS: What is wet sandpaper ?

Edited May 15, 2018 by Chopin

[rogart63]

Have you checked cousinsuk there special crystals. 

[Chopin]

What do you mean by special crystals ?

I have checked all the categories (as far as I know) and only 2 or so came close but they were still off by a bit or the shape was different.

[manodeoro]

3 hours ago, Chopin said:

Yeah I think I can find something like that. Did it come with the entire set of bits ? That's very nice.

PS: What is wet sandpaper ?

Yes it come with the entire set ... some are usefull and some useless

I have upgraded the kit with HS drilling bits, diamond grinders, etc ... plus of course polish buffers and compound paste

This evening I'll check my DEXTER max power (watts) and post it here so that you have an idea of what you need.

What is also important is the speed range.

You must have low speeds to drill SSteel or grind plexi, and high speeds to grind and/or polish SSteel.

 

water sandpaper is "wet-an-dry" sandpaper ... the one you can use it dry or moist it before sanding 

[Chopin]

Cheapest one (not necessarily the one I'll buy) that I found is this one. Speed is 15.000-35.000 rpm. Is the 15.000 minimum speed too much ? Power is 135W.

Speaking of bits what are the ones that you'll use on a watch ? I know that the white felt ones are used for polishing/buffing. I'm assuming the brown sandpaper ones for shaping crystals. Anything else ?

Might get this one which is a tad more expensive.

Edited May 15, 2018 by Chopin

[jdm]

23 minutes ago, Chopin said:

Cheapest one (not necessarily the one I'll buy) that I found is this one. Speed is 15.000-35.000 rpm. Is the 15.000 minimum speed too much ?

I think it is. Almost any work is better done at slow speed, I don't know why they use motors so fast when the declared power is high, the only result is that you wear out the bits much faster. My Proxxon starts at 5K and the bench polisher even less.

[manodeoro]

I think it is. Almost any work is better done at slow speed, I don't know why they use motors so fast when the declared power is high, the only result is that you wear out the bits much faster. My Proxxon starts at 5K and the bench polisher even less.

Proxxon is the best .... but far more expensive.
If I would buy a static drill stand or a lathe I'll probably buy a Proxxon.
I'll check the lowest speed of my Dexter later when back home.

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[manodeoro]

4 hours ago, Chopin said:

Cheapest one (not necessarily the one I'll buy) that I found is this one. Speed is 15.000-35.000 rpm. Is the 15.000 minimum speed too much ? Power is 135W.

Speaking of bits what are the ones that you'll use on a watch ? I know that the white felt ones are used for polishing/buffing. I'm assuming the brown sandpaper ones for shaping crystals. Anything else ?

 

 

I'm just back home and checked my Dremel-like.

Power is 135W and speed is 10.000-38.000rpm (variable speed).

I often use it at the lowest speed and sometimes I would like it to go a little slower

So sorry to say that but YES ... I think 15.000 minimum speed is too much

 

About the bits that comes with the driller those I use the most are :

- flexible shaft !!! it's a MUST HAVE (and the cheapest one you showed dont have it so you'd better forget it)

- the buffers - to polish

- the grinder - I dont use them "as is" but with sandpaper of different grades sticked on them with double-sided tape

- grinding disks - to redo chamfers on cases and lugs that have been overpolished

The other bits have proved to be a little useless ... drill bits for wood and/or soft metal and not for stainless steel, etc ...

So I have updgraded the kit and I'm still happy with it 

[Chopin]

Alright, thanks. I'll use all this information when I make the purchase.

I'll definitely get one with a flexible shaft as you call it. That is indeed a must for what we do on watches.

In the end the machine is the one that matters, the bits I can buy everywhere and there's a wide variety.

[jdm]

12 hours ago, Chopin said:

I'll definitely get one with a flexible shaft as you call it. That is indeed a must for what we do on watches.

Get a stand support first. That will let do all the work comfortably. As a safety measure place something like sticking rubber or texture tape it on the screw head. Even better, use double side tape as suggested above.