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Best Machine for crystal repair


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Hello. I recently received my diamond pastes and have had some success using a leather band and microfiber along with the pastes to reduce and (in some cases) remove scratches from the lenses of various watches. I am wondering now how to bring the process from hours to minutes. I want to be able to polish metal bands as well, but glass & crystals are my main focus. I have found that all the rorory tools run at 10k to 35k rpm. I know i need more like 1k to 7k rpm. Are these possible to find? does anyone have other suggestions? I looked into bench polishers. These look great for bands, but i dont have a garage and im not sure this is the best option for removing scratches from crystals and glass lenses. what is recommended for doing this at home? thanks in advance.

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This isn't a answer that comes from a watchmaker perspective. I've used a baldur buffer to buff briar smoking pipes. Worked a wonder on a plastic crystal as well(change the wheel[emoji1787] carnuba does not do great on a watch crystal). If you happen to have access to one it'll work great.

Now to see what a real watchsmith recommends. I just play with my own watches.

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Since the objects you are polishing are relatively small, you could fabri-coble together a small polishing machine using a 12V motor with built in gearbox. Something like this (search ebay for motor 1000 rpm, for lots of other ideas).

https://www.ebay.co.uk/itm/DC-3V-6V-12V-N20-Micro-Gear-Box-Geared-Motor-Speed-Reduction-Motor-Electric-HL/163064234690?hash=item25f762c2c2:m:mGGGwyKyZWTloM7wviCPQDQ:rk:1:pf:0

Most Dremel type tools have some sort of speed controller, which often lets you go pretty slow, but there is usually a trade off between power and speed.

Also try searching ebay for "jewelry polishing tool" and "dental polishing tool", you will see a plethora of different types of buffing and polishing stuff.

To remove scratches from crystals, I tend to go for the simplest method, and polish by hand, but it does take a fair bit of time, so if you do come up with a near perfect motorised solution, which doesn't take up too much space let us know.

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4 hours ago, Anthony1979 said:

Hello. I recently received my diamond pastes and have had some success using a leather band and microfiber along with the pastes to reduce and (in some cases) remove scratches from the lenses of various watches. I am wondering now how to bring the process from hours to minutes. I want to be able to polish metal bands as well, but glass & crystals are my main focus. I have found that all the rorory tools run at 10k to 35k rpm. I know i need more like 1k to 7k rpm. Are these possible to find? does anyone have other suggestions? I looked into bench polishers. These look great for bands, but i dont have a garage and im not sure this is the best option for removing scratches from crystals and glass lenses. what is recommended for doing this at home? thanks in advance.

Personally I found it just easier and quicker just to replace the crystal. I have polished out small scratches in the past. I have attempted the deep scratches but I found it so time consuming I just don't bother any more. 

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I've only polished a glass crystal once.  It was deeply scratched, about 0.3mm deep, and I used wet papers from 400 to 5000 grit.  I tried a Dremel with cerium oxide on a 25mm felt mop for final polishing but it was far better at pebble-dashing the walls than polishing the glass.  Finally I used the same mop in my drill press, set to 700 rpm, which did the trick.  The whole process took me about 5 hours so I'm not keen to repeat it.

I did wonder if the wet/dry part of the process could be mechanised in some way to speed it up.  I imagine that any kind of handheld rotary tool could easily cause optical aberrations in the crystal simply by removing more material in some areas than in others.  It occurred to me that it might be possible to use an orbital sander upside down with the abrasive paper secured somehow to the baseplate.  While that might work for a flat crystal it might not be so good for a curved profile.  Also one would need to prevent water getting inside the sander.   Just random thoughts, not sure what the solution for Anthony1979 might be.

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i have seen this done in videos. it seems most recommend a bench grinder/polisher (see links), at least for metal bands. im more worried about plastic, glass, and crystal. is it the common understanding that a bench polisher is best for both? and what about the bench polisher that comes with a rotary tool? (see 2nd link). i know this can be done by hand. ive been doing it, but ir takes so long and i have many watches that need work and would like to offer this service to others. i will post bench polishers here. but does anyone recommend a low-spees rotary tool instead? thanks.

https://express.google.com/u/0/product/2168378828946594147_5865200031692559150_122960208?utm_source=google_shopping&utm_medium=tu_cu&utm_content=eid-lsjeuxoeqt&gtim=CJ7Ltr-IyOnoOBD_4cnElPv61yUYsIX4KSIDVVNEKKCHluEFMNDy0Do&utm_campaign=122960208&gclid=Cj0KCQiAgMPgBRDDARIsAOh3uyKoFbCOqRfbqCpdXVfNQYNEwi1B_HRN2Fcr0roYa_vxl-7I6mnI29caAo3EEALw_wcBb

 

https://express.google.com/u/0/product/6245911414029742817_13149907706747406468_123673039?utm_source=google_shopping&utm_medium=tu_cu&utm_content=eid-lsjeuxoeqt&gtim=CI73q7b8n7e0BhCLrdTv5rm3u2YY4OXoFCIDVVNEKKCS8eAFMM-z_Do&utm_campaign=123673039&gclid=Cj0KCQiAgMPgBRDDARIsAOh3uyL6rosEU6TCMauw2u5yk3pvUYK_iqVc6fbsDyfs3HN1LiCUsMGv41EaApbfEALw_wcB

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is there a machine that it ideal for both metal bands and for lenses? After spending a few hours on a lens (glass i think) of a citizen elegence watch that i wore to work at a foundry. (to decent, not perfect, effect), i went ahead and used the same spectrum of diamond pastes and a leather band to polish the steel band. while it did not remove the scratches conpletely, it did soften them, as well as put a nice shine on the band. the watch looks 90% better. i have no "before" pics. but i will show what it looks like now. take my word for it, this was looked like it was run over by 10 cars. so i know the paste works (if someone has a better recommendation for steel, id love to know). 

20181212_231120.jpg

20181212_231146.jpg

20181212_231207.jpg

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sorry to triple post guys. if a bench polisher is the way to go for metal bands, ill get one. just wondering if ill be able to use it for scratches on plastic, glass, and crystal as well. id also like to know if there is better paste for the bands than the diamond pastes im currently using to hand-polish crystals. i live in an apartment. no garage or workshop. i do my work in my bedroom. i know there are expensive solutions out there. im looking to set this up for under $100. thanks

Edited by Anthony1979
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I have a set of shapton glass sharpening stones and this is the method I use to get them dead flat if they begin to dish. As long as the crystal is truly flat this is a heck of a idea.

If you have a glass crystal that you need to polish - do it with a piece of glass!

I used emery papper before - it works but with a piece of glass it's super fast and the results are way better!
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the basic idea for time efficiency with any abrasive finishing/polishing is start with coarse and work your way to fine.  The finest abrasive that will finish the crystal will take forever to remove a scratch.  i start with emery paper, 1200, 600 irrc if its really rough, work up 2000 or higher (you can get it up 8000) and finish with brasso.  This leaves an excellent finish on a crystal.  I have down probably a few dozen indicators this way, same idea, plastic scratched crystal. 

I don't usually use power for this, not necessarily, but a foot controlled foredom would address speed control

Edited by measuretwice
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