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Mark Patoka
11-11-2009, 4:04 PM
I'm trying to cut my own glass for a cabinet door I'm making. It will have 6 panes of glass, each approx 6" x 8". I bought one of those basic glass cutting tools and am using regular glass from picture frames.

I've watched enough online videos that it can't be hard but I can never get the break to completely follow my scratch line. It may follow the scratch line 1/3 of the way, sometimes more before it, well, looks like broken glass, making the piece I'm trying to cut unusable.

The videos make it sound like the tool makes a nice scratching sound, I hardly get a sound at all. I've tried using the tool/wheel dry, with a drop of oil as lubricant, tried pressing hard enough to almost break the glass, about every combo on lots of practice pieces and it just won't break completely along the scratch line.

Do I have a faulty tool and need to just buy another one that will give me a deeper scratch? Every video makes it look so easy there should be no problem.

Any suggestions?

Bob Vavricka
11-11-2009, 5:44 PM
Mark,
Is this new glass or some you are reusing? I'm not a glass cutting expert, but from what I understand older glass can be rather difficult to cut.
Bob V.

David G Baker
11-11-2009, 5:50 PM
Bob is right on cutting green glass or new glass. Older glass has a tendency to get brittle with age and much more difficult to work with.

Tim Boger
11-11-2009, 5:52 PM
I'm trying to cut my own glass for a cabinet door I'm making. It will have 6 panes of glass, each approx 6" x 8". I bought one of those basic glass cutting tools and am using regular glass from picture frames.

I've watched enough online videos that it can't be hard but I can never get the break to completely follow my scratch line. It may follow the scratch line 1/3 of the way, sometimes more before it, well, looks like broken glass, making the piece I'm trying to cut unusable.

The videos make it sound like the tool makes a nice scratching sound, I hardly get a sound at all. I've tried using the tool/wheel dry, with a drop of oil as lubricant, tried pressing hard enough to almost break the glass, about every combo on lots of practice pieces and it just won't break completely along the scratch line.

Do I have a faulty tool and need to just buy another one that will give me a deeper scratch? Every video makes it look so easy there should be no problem.

Any suggestions?

Your local HD will cut for free if you buy the glass there, if your using 1/8 inch it costs almost nothing.

Tim

James Stokes
11-11-2009, 6:09 PM
Cutting glass takes a little practice. When I was a young man I went to work in a glass shop. My first day there I did absolutly nothing but work on cutting glass. By the end of the day I was not having much problems any more.

The main thing you need to do is hold your cutter straight and make a smooth draw with the cutter. You should have an even line with no skips. Then use your table, line your cut up with the end of your table pick up one end of the glass hanging over the table lift it up and then snap it down on the edge of the table. That was how I was taught to do it.

Perry Holbrook
11-11-2009, 7:04 PM
I cut lots and lots of glass. I would guess that you are pressing to hard. You only need about 5 to 7 lbs of down force to score properly.

Dip the cutter in paint thinner before each score. If that doesn't help, PM me and I'll see what else I can suggest.

Perry

Dave Johnson29
11-11-2009, 7:47 PM
I bought one of those basic glass cutting tools and am using regular glass from picture frames.


How sharp is the edge of the glass cutting wheel? I have seen some with a pretty smooth rounded corner. You may need to sort through them at the hardware store to get a good one.

Hold the cutter between your first and second finger and perpendicular to the glass surface. As Perry says not too much pressure. I use a piece of cloth with WD40 sprayed on it. I make a short run on the damp cloth to lube the wheel then cut.

To break, I lift the glass up with my thumb over the cut on one edge and slip a piece of thin wood, maybe 1/8" x 1" under the full width. Lay the glass back down on that then push down on the overhanging edge.

Perry Holbrook
11-11-2009, 9:41 PM
For regular single strength glass like you are cutting, the easiest way to run the score is to hold the glass with both hands along the edge with each thumb on either side of the score. Then with a twist of each wrist pulling out and down you sort of pull the glass apart along the score line. If you feel un-easy, wear a good pair of leather work gloves.

Perry

Joe Pelonio
11-11-2009, 10:08 PM
I do stained glass work and have cut a lot of glass, and yes, it should make a nice scratching sound. Most people make a mistake with the angle holding the tool, and the frame keeps the wheel from making good contact. You should practice on scraps first. For large pieces the table edge method helps, but the best tip is to score quickly and snap immediately, wait too long and it won't break right.

Neal Clayton
11-11-2009, 11:51 PM
get a diamond tipped cutter. they hold an edge infinitely longer than the steel wheel type.

the steel wheeled ones will wear out very fast if your technique isn't good, which for the first few times won't be. diamond tipped cutters are much more forgiving.

lots of arts/crafts supply stores on the web sell them, probably 20-30 bucks.

Perry Holbrook
11-12-2009, 7:12 AM
One other tip, never go back over your score line a second time. Not only does it cause breaking out problems, it damages the cutter wheel to make future cuts difficult.

Mark Patoka
11-12-2009, 8:52 AM
Thanks for all the tips. The glass I'm using is from a friend that buys low-cost picture frames from x-Mart for her oil paintings and doesn't need the glass, so it shouldn't be anything special. I've practice a fair amount with all my pieces that don't turn out using the table break method, the two hands method, score the line once, etc. with the same basic result. I'll look at getting another/different cutter. The one I have is new from the Borg and just seems to roll along the surface, hence very little cutting action.

Randy Cohen
11-12-2009, 9:06 AM
It seems to me that you could use a tile cutter but some of these other guys are more glass aware than I am. the tile cutter I mean is the one with the wheel mounted to a guide on top and then a sort of v shaped piece that you push down on to snap the tile.

Joe Pelonio
11-12-2009, 10:30 PM
The tile cutter has a wider blade and the pressure is meant for tile and could shatter glass. It may work but only with a real light touch.

Dave Lehnert
11-12-2009, 11:35 PM
I picked up some glass pliers at Harbor Freight the other day like the ones in the pic below. Got them because they were only $3. Have no idea if they work. Never used them yet.

http://t2.gstatic.com/images?q=tbn:erzyKNjYUJoB1M:http://img.alibaba.com/photo/104031643/8_Glass_Pliers.jpg

Paul Atkins
11-13-2009, 12:49 AM
Glass pliers are a good tool - if they are used right. The sharp wheel and a determined cut are the most important though. Just like the skew - do it or don't.

Neal Clayton
11-13-2009, 1:48 AM
I picked up some glass pliers at Harbor Freight the other day like the ones in the pic below. Got them because they were only $3. Have no idea if they work. Never used them yet.

http://t2.gstatic.com/images?q=tbn:erzyKNjYUJoB1M:http://img.alibaba.com/photo/104031643/8_Glass_Pliers.jpg

pliers are good for trimming, so worth having. if you get an unclean break using the "table edge slam" method you can trim it up with the pliers. also if you need to cut small pieces, for instance with stained glass, breaking with the pliers is the only way, and in that case it's a necessary tool.


Thanks for all the tips. The glass I'm using is from a friend that buys low-cost picture frames from x-Mart for her oil paintings and doesn't need the glass, so it shouldn't be anything special. I've practice a fair amount with all my pieces that don't turn out using the table break method, the two hands method, score the line once, etc. with the same basic result. I'll look at getting another/different cutter. The one I have is new from the Borg and just seems to roll along the surface, hence very little cutting action.

from my experience with glazing windows, i struggled with a wheel cutter when i started learning the technique too. the wheel cutters work fine if you have good technique as far as pressure and stability of your hand and everything else. that's difficult to get right when you first start cutting glass, though.

the diamond tip cutters have much more leeway with pressure and how steady your hand is. therefore they're easier to learn with. if you cut enough glass to get proficient with the diamond tipped cutter, you can probably go back to the wheel as a backup and not have any trouble, but the diamond tip cutter will save you a trashcan full of poorly cut glass in the meantime ;).

Jim Sears
11-13-2009, 7:01 AM
I don't know if this has anything to do with it or not, but I always spray a fine mist of window cleaner on the glass before I score it. Seems to work for me.

Perry Holbrook
11-13-2009, 10:20 AM
Looks like we're having a tutorial on glass cutting going here. The post above reminded me of another tip. The glass needs to be cleaned of dust, etc before cutting. If there is dust along the score line, it actually raises the cutter wheel off the glass in that spot, which creates a gap in the score, which can cause a poor break out.

Cutting glass really isn't has hard as it my seem. Actually it is quite easy. There is just a learning curve involved.

Perry

Dick Strauss
11-14-2009, 12:40 AM
You need to start with a flat surface that fully supports the glass over the length of the score. Score the glass once (don't go back) starting as close to the edge as possible using a straight-edge. Use your off-thumb to keep the wheel from rolling off the edge and your off-fingers to hold the straight-edge while making the score. Stop just before you go off the far edge (otherwise you might crack off the far corner). You should hear a slight scratching noise as you score if the pressure is right. You can score in either direction but you do need plenty of pressure (I push cut because I feel I can keep better pressure when working with extra thick 1/4" plate or stained glass). Keep your cutter under your shoulder (if possible) to keep good downward pressure. If you end up with a fine scratch across the piece, the breaking should go pretty smoothly. If you end up with glass dust along the crack, you used too much pressure.

Don't use the ball end or pliers to finish the break...you don't need them!

Since you are a novice, score one line and break the glass. Score another line and break the glass. Definitely don't score two lines that cross over each other as a novice! Glass tends to break in a straight line but will wander if you give it an alternative path.

A good pistol grip cutter with a carbide wheel helps to get pressure down to the glass. The cheap old cutters make it harder to cut glass efficiently IMO.

You can use 1/2 veg oil with 1/2 kerosene as to lube your wheel. If you use straight veg oil for lube, make sure you clean the wheel when you are done, otherwise it will be gummed up the next time you need to use it.

FYI-I've cut 1000+ ft of 1/4" plate and 1/8"+/- stained glass.

If you have any more questions or find something I wrote confusing, please feel free to PM me.

Good luck,
Dick

Eric Robert
11-15-2009, 9:53 PM
yeah, I used to have problems cutting glass also. Much what other people have said, just make sure its a smooth even cut. Doesn't always require alot of force to say. I recommend to try not making any pauses while cutting. Have a nice consistent motion and then lightly tap. I can't remember what the link was, but there was a great tutorial on youtube.

Mark Patoka
12-02-2009, 5:12 PM
Just an update - I was at Michael's craft store and found the Logan glass and mat cutting system they have there. I bought the glass cutter and Adapt-A-Ruler using their 50% off coupons.

Tried it out and the very first cut broke so easily and cleanly I couldn't believe it. I had my 6 panes cut in no time. Apparently the cheap cutter from the Borg was faulty from Day 1.

The cutter cost $30, $15 with the coupon, and I recommend it.

Eric Robert
12-03-2009, 5:38 PM
Looks good, I think I am going to have to give this a try to cut up my glass for my etching projects. Lets be sure it lasts long thought. Either way the blade or roller is probably very cheap to replace. Thanks for letting me know about this.


Just an update - I was at Michael's craft store and found the Logan glass and mat cutting system they have there. I bought the glass cutter and Adapt-A-Ruler using their 50% off coupons.

Tried it out and the very first cut broke so easily and cleanly I couldn't believe it. I had my 6 panes cut in no time. Apparently the cheap cutter from the Borg was faulty from Day 1.

The cutter cost $30, $15 with the coupon, and I recommend it.