How to Bevel Glass
 

I need to bevel glass with my MM. Can some one please advise me on how to get about it, specially on the router bits that are required.

Hi Fabrica,

You should use mandatory a diamond tipped bit.
Check this out

Greetings
Claus

Hi Fabrica, great to see that you are still around! A lot of the MechMaters here joined after you went quiet, but they need to know that you hold serial #1 :)

Okay, that is the inroduction . . . . let's see if someone has glass bevelling experience

Hi Fabrica,

Sorry to be negative, but I would advise extreme caution before attempting to use your MM for bevelling glass.
Very small errors in a bevel produce easily visible defects that are very difficult to polish out due to the hardness of glass.
Also the tools are expensive & water cooled and the water/slurry gets all over the machine.
Dedicated machines have all stainless steel components, and dedicated water drainage,filtration and recirculation .
The machines are also very heavy duty and powerful.
Using standard cup tools, you must angle the head. Not too hard for straight edges, but curves are a different ball game.


I work in the glass industry and have worked with CNC machines for cutting, edging and engraving glass.
We have looked into dedicated CNC bevelling machines and decided it was not feasable for us.
They all had issues with accuracy,quality and production time, and these were £100K+ machines


The Edging CNC machines we have that produce glass balustrading/table tops etc are VERY heavy duty machines.
They are Intermac/Biesse machines that are about 6 tonnes.

As everyone knows, glass is very hard and brittle. It is harder than granite.
The tools used are diamond grit embedded in metal or resin.
For bevelling, cup wheels are used. usually 3 grades (Coarse,med,fine)
Then the bevel must be polished with a felt wheel & cerium oxide.
The tools are very expensive £100+ each, although they do last a long time.
I don't know what power the spindles are, but they are much, much bigger on our Intermac/Biesse's than on a typical MM.

Lots of water is required to keep the tools cool.
As a guide you need about six jets of water surrounding the tool, each jet equivalent to a good garden hose.
The water requires drainage and the slurrey is very abrasive and corrosive. It gets everywhere.
Spindle speed control is essential as different speeds are required for different wheels.

I'm not saying it's impossible. I have seen some amazing stuff done with MM's.
However i do think the chances of success are very, very slim.

Cheers
Greeny

Some links:
http://glass.intermac.com/ProductDet...=130,Master,35
http://www.eborstone.co.uk/shop_prod...Diamond_Wheels
http://www.beveledglass.net/HANDBEVELING.html (scary:eek:)

Hi Claudiu, Gereald and Greeny,

Sorry for not being able to keep in touch with you guys. but when ever I have time I just have a quick peep on the happenings in the forum.

Gereld as you know Gerald this CNC buisness is niether my breadwinner and neither it is my hobby. I took up the Challenge thown at us by you and did up the machine in extra quick time. Thanks for your nice compliments Gerald.
Recently one of my freinds approached me and asked me weather I could do some wood work for him for the house that he is putting up. So I just thought of revving up the old work horse again.

Greeny thanks for your very informative reply. I will post a few pics for you guys so that you will know what am after.

I am proud to see so much of cativities taking place in this forum. Gerald you must be a busy and a happy guy.

This is a pic of the work that we are doing. First we cutting these pockets in a 2" thick piece of mahogany. We will be mounting this on top of two window panes. The glass has to get into the holes and they have to be bevelled.

Hi Fabrica….
Long time…. Nice to see & read some news from you.
Hope to read more soon & good luck on your beveling quest!
Robert ;)

Thanks, Robert.

Fabrica,

Vary nice wood cutting. Time more time to post.

Hi Fabrica,

Those outer pieces have 'shoulders' with an internal corner or radius.They are very hard to bevel.

I cannot stress enough how hard that would be to do on your MM.
Even cutting that shape out is difficult and would probably need drilling first,

If it was me I would contract the glass job out to a manufacturer who has the equipment.
They would probably use a semi automatic bevelling machine such as this.

I know i sound very negative, but i'm really trying to save you a whole heap of wasted time,money and energy.

Cheers
Greeny

Thanks Greeny for your kind advice. What you say is true. Might as well get a professional who has the equipment to handle the job. This jon is beyond the scope of a MM. My other option would be to apply sticker on to normal glass to give the bevel effect. I am searching for a suitable sticket manufacturer.

You could acid etch the edges to give a faux beveled look. It's really easy to do and you wouldn't be at the mercy of finding the right stickers.

Does it have to be glass? I bet you could bevel acrylic on the MM.

Good Idea Leko. I will follow it up.

You could also sandblast the edges only for another effect. Masking the rest of the pane.

That is to get the frosty effect, is it? Are you reffering to glass or acrylic.

Fabrica,
Yes the sandblasting give a frosted type effect. I would think similar to the etching? No chemicals involved though. :)

Fabrica,

Could this be of any help:

http://www.rockler.com/articles/disp...fm?story_id=59

good luck Polder

Thanks Polder for your input. I followed up your link that too is very interesting. All options that have been provided to me through this forum has been fowarded to my end user. Let him decide. Hats off for all the guys who have helped me out in this venture. Further inputs are most welcome.

I followed a hit on my glass beveling site. Found a link from this board. MARKED (scary)
:eek: Just wondered, what is scary.
Dennis Swan

I think that Greeny, in post #4, was surprised to see that you still have your fingers intact..:)

All of them are still here, get a little close at times.
Dennis

how much damage would there be to the wood if you poured molten glass into the pockets?

Common glass has a melting point of about 1500 Deg C
Wood ignites at around 300-400 Deg C

How much damage it would cause depends on how quickly you could put out the raging inferno that once was your workshop :)

Ah, Greeny.... you spoil everything with your darn facts and science. Now I can't get rid of this mental image of myself running around trying to put out a self-induced inferno.... :D

Ah, but I wasn't too far off.

http://en.wikipedia.org/wiki/Glass_casting

Sand casting from a wooden plug is possible, and cast glass is general is not so uncommon. He could cut a plug, make a mold from that out of another material, and then cast his own glass bits to fit exactly.

One could also choose a clear resin for outdoor use and fill the voids with that.

An inside miter to bevel in glass is a no-no. On some old grandfather clocks I bevel them with a slight inside radius in the inside corner. But these are usually covered with wide stops. Besides they are a real pain to do, so for several years now I pass on the work.
No getting around custom hand beveling if you want real glass in these. Semi-automated bevelers do not do very tight inside curve bevels.
Sounds best to try a fake beveled look with vinyl or an etch of some sort.
Dennis
http://www.beveledglass.net