Cutting and sanding glass - dummy alert!

[abitfishy]

Hey all,

When I eventually work out the best way to cut the wood, :? I intend building a few small reptile enclosures. The doors are going to be sliding glass in the 4 or 5mm plastic track that you can buy at Bunnings. I have so many bits a pieces of glass lying around it seems silly to buy some - but my 2 questions are:

1. Is using one of those cheap glass cutters to score the glass and snap it down the score line accurate, or does one get cr*ppy edges etc?

2. Whats the best way to get a smooth, rounded edge on the exposed ends of the glass, rather than the sharp cut edge? Or can this only be done by the pros?

Since glass tends to be expensive, yet theres so much of it around that noone wants (including old fish tanks), seems like theres a bit of dough to be saved.

Thanks
Martin

[ozwinner]

Use silicon carbide paper, (its the black paper,) it will take the edge of glass no worries.
Start with something like 240 grit, and if you want it smoother progress to 480 grit.

Just do it by hand with a longish sheet and roll the sheet over the edge a coupla times.

Al :)

[silentC]

Yes you can cut accurately with a glass cutter but there's definite knack to doing it and you wont pick it up quickly. Practice on some offcuts first.

Arrising or rounding is done on a machine. You can simulate an arrised edge using a block of carborundum or sandpaper but you wont get a nice clean edge this way. If it's for show, you really need to get a glazier to do it for you. It might be worth taking your cut sheets in to see if they will arris them for you if you can find someone who'll do it.

I once built a machine using a beltsander but it was only marginally better than doing it by hand. I mainly used it when people wanted the edge taken off but it wasn't for show.

[Studley 2436]

The glass cutter to go for, I can speak on this as I cut glass all the time for picture frames is the one with the oil inside it and a cutting wheel at the end.

Use a straight edge to go along the edge and start the wheel on the glass. You will hear a scratching sort of noise if you are using enough pressure.

When you "break" the glass you can do small pieces just in your hands by holding each side and bending it a touch. Larger pieces it's best to put a bit of wood or something straight under the glass and lay it down on the wood

Studley

[Bleedin Thumb]

I'm just about to do some myself and did a google to learn the tricks.
Studleys nailed it - well from what I've read. also just one score don't go over vthe line repeatedly.
Silents advice was also offered - get some scrap and practice.
I'll let you know how I go... I'm building the boys an ant farm..Yeeehaaa.

[ozwinner]

I'll let you know how I go... I'm building the boys an ant farm..Yeeehaaa.

Better get some Aloe Vera in, Im sure your boys will itch with ants on them..

Al :o

[watson]

G'day,
My only input...being a glass miser.......is that glass gathers dust/bird crap/all sorts of stuff. After cutting several bad bits I learned that if you clean the glass first, then follow all the advice the forum just supplied, you'll get good straight edges, If my missus wants her Enjo stuff back I'm buggered.
But squeaky clean glass cuts good! or well, or some other word!!

Regards,
Noel

[ozwinner]

But squeaky clean glass cuts good! or well, or some other word!!

Regards,
Noel

Gooder?

Al :2tsup:

[watson]

Indubitably!
Clean glass gives good cuttage!
Regards,
Noel

[JDarvall]

Even pressures the trick when ever cutting glass, simply because glass doesn't like to bend. ....so think about a good flat table....

Score the line running the glass cutter along the wood.....helps to clamp the wood to the glass with padded clamps, so it won't slide on ya....can concentrate on making a good score better.

I'd use a straight wooden edge under the score line regardless of how thick the glass is........put even pressure on the piece your bending over with another piece of wood under your hand.......It should just click right off real quick......3-4mm glass a piece of cake, which sounds like all you'll need.

Try and make the score with just one pass from edge to edge....if the scores not complete (which is easy to do). ...especially near the ends.....well it won't break straight

Definetly practise on scrap first like said.....don't expect to pull it off first time....but its easily learn't.

[olddog]

Hi Martin, Get your self a diamond sharpening block from one of the tool markets about $10/15.00 they come in a wooden box and take the edge off glass with ease....Peter

[abitfishy]

Thanks for the responses guys. Much appreciated.

I will take them onboard, and let you know how I go.

Martin

[joe greiner]

For a really smooth rounded edge (smooth as glass, one might say), I think the pros use what's called "fire polishing." I don't know what kind of flame or torch they use, and I haven't had the nerve to try it myself.

Joe

[pawnhead]

With the cheap wheeled ones you have to put quite a firm pressure on to ensure an unbroken score line, so the break doesn't wander. If it does wander a bit, then you can nibble away the excess with the jaws on the cutter. They go blunt fairly quickly, and they can rust, but that's not an issue if you've only got a few panes to cut. Follow Bleedin Thumb's advice and don't try to go over a line again or it will kill the blade straight away.
I've seen the pros use non rotating, diamond tipped cutters, and you may be able to pick up one of the lesser quality ones quite cheaply. You won't need nearly as much pressure for an unbroken score line and you'd notice the difference straight away if you've used both. There's less chance of the break wandering, and they last heaps longer.
You could probably take your glass to a glazier and he'd cut it for you in a few minutes for a few bucks, but he wouldn't guarantee success when cutting old glass.
Prepare for some failed attempts if you're tackling it yourself, but as you say, it's all over the place at every council clean up, and I've got a bit of stock under the house if I need any.
Gooder?
Indubitably!
That's most cromulent (http://en.wikipedia.org/wiki/Overlord_meme#Cromulent) terminology you're using there guys.

[silentC]

I used to cut the stuff for a living. Here's a previous post on it:

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=7326

FWIW We didn't rate the diamond cutters very highly. We tried one but always went back to the wheeled cutter. Might have been a knack thing but you stick to what you're used to I suppose.

[pawnhead]

I used to cut the stuff for a living. Here's a previous post on it:

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=7326

FWIW We didn't rate the diamond cutters very highly. We tried one but always went back to the wheeled cutter. Might have been a knack thing but you stick to what you're used to I suppose.Looks like some good tips in that thread, especially about the tile cutting blade in the saw. :U

You're probably right since you've done it for a living. I just remember that the only time I've noticed a pro using one, it was a diamond tip. I've never had as much luck with the $2 wheeled jobs that I've bought, so I splurged out quite a bit more for a diamond tip, and I've still got it after having done a fair bit of cutting with it. I suppose If I'd bought a more expensive wheeled cutter in the first place it might have been a different story though.

[silentC]

The diamond tip ones are popular with leadlighters because they're good for cutting shapes. I think it's just a matter of what you're used to.

The ones we used were Diamantor brand - green handles made in Germany. I think they were more than $2 each though...

[Studley 2436]

I am very happily using a wheeled cutter, very easy to to a straight edge and it cuts curves too if you want to get into that sort of thing

Studley

[abitfishy]

Thanks guys, bit of a long post, here I go:

I bought one of the wheeled supercraft brand oil filled jobbies from Mitre 10, and have pretty much got cutting glass down pat. Great fun to do. Although I've stuffed 2 nice bits of glass in doing so (I practised, got it right, then stuffed the 2 good bits, typical!!). I think I've worked out where I'm going wrong, as I seem to have trouble getting even pressure down the hole line, and where I've backed pressure off it tends to crack inwards. I don't think it was a problem with the practise bits as they were about 2 or 3mm, the good bits were 5mm so probably needed a slightly deeper 'cut' (so to speak).

I've ordered a 'pro' quality Toyo outrigger grip glass cutter that might make it a bit easier to keep constant pressure, and will see how I go. About $45, but if it does a good job, its a cheap tool. Also ordered a hand smoother that has 2 stones in it that you run along the edge to smooth the sharp edges - $28 - what a bargain. This was from a speciality glaziers place.

Now, another job I was going to do with my new skills was to build a custom frog tank, but I wanted to use stainless steel or chrome 90 deg brackets designed for glass to hold it together, as well as they would make a nice feature on the tank rather than 4 sides of plain glass - but worked out I needed 10, and they were $35 each!!! I could buy a frog mansion for that money - anyone know where one could get better priced brackets, hinges etc designed for glass??

[rod1949]

Wouldn't using carborumdum paper or sandpaper to arris the initial and very sharp edges be very dangerous?

[silentC]

What, in that you might cut yourself? Well, yes you could, if you don't take precautions. You might also cut yourself when you lift the sheet after cutting it. In fact there's a hundred ways to cut yourself on glass.

We always rubbed a block of carborundum over the edges of glass we cut for customers to take away so that they didn't cut themselves lifting it in and out of their car.

If you're concerned about cutting yourself, wear gloves and wrap the sandpaper around a block.

[rod1949]

What, in that you might cut yourself? Well, yes you could, if you don't take precautions. You might also cut yourself when you lift the sheet after cutting it. In fact there's a hundred ways to cut yourself on glass.

We always rubbed a block of carborundum over the edges of glass we cut for customers to take away so that they didn't cut themselves lifting it in and out of their car.

If you're concerned about cutting yourself, wear gloves and wrap the sandpaper around a block.


Well yes. I wouldn't use any of the thin sheet papers cause of the safty factor and I don't think they would last that long. I'd be using a carborundum block (ie an old wheel off a bench grinder).

[silentC]

As I say, I built a machine using a belt sander to do it. The belt was oriented so that it revolved perpendicular to the edge of the glass. You can buy special belts for the job but I mostly just used a fairly coarse grit belt of the type you can get at any hardware shop. They lasted fairly well.

I wouldn't expect great results using sandpaper by hand though, and as I say, we used to use a block of carborundum to do it. This was a rectangular block that can be bought for the purpose, although I believe it has other uses, such as cleaning oilstones etc.

[Bleedin Thumb]

- anyone know where one could get better priced brackets, hinges etc designed for glass??


Try Glen at High Standards 9476 3229 he is a broker for all things stainless and delivers them to you usually cheaper than people like Coventry Fasteners who are at Taren point so are close.
Also Lincoln Sentry specializes in those type fittings but you have to know what you want because I find them unhelpful - ask for a catalogue or maybe they have a web address.