First time drilling glass

[Ratpack]

Well, I practiced on one hole tonight in 5mm window pane glass and it came out pretty good. Anyone know if window pane glass and aquarium glass are the same other than thickness? There was some chipping as the hole saw broke through. That may have been from a little too much pressure though. I am pleased so far and plan to practice some more before drilling my tank, but I do have a few questions and haven't really found the answer in other posts. First, would it not be better to drill from the inside of the tank to the outside so that any chipping is on the nonsealing surface for the bulkhead? And second, just how much chipping is "normal" or acceptable? And third, I assume that when starting, if it jumps, then the scratch is pretty harmless other than cosmetic, right? I am drilling the back panel and it will be painted black afterwards anyway.

One note that I didn't like about the method I used though. I used the dam of putty with water in it, worked fine except I could not see when I was getting close to breaking through and thus start to let up on the pressure. I think I will try the hose with a trickle next time.

[scubadude]

Congrats Ratpack!

Dontcha just love it when a DIY works out for ya

First, would it not be better to drill from the inside of the tank to the outside so that any chipping is on the nonsealing surface for the bulkhead?

I agree chipping should be on the nonsealing surface for the bulkhead

second, just how much chipping is "normal" or acceptable?

Well when you said window pane glass, im thinking 3/8" or 1/4" thickness glass that is usually tempered this thickness is harder to drill sometimes cuz its so thin, i think the chipping is normal probable.

third, I assume that when starting, if it jumps, then the scratch is pretty harmless other than cosmetic, right?

Yeah your right....even more so like you said since your gonna paint it. I think you will do fine even w/out your putty dam

[Ratpack]

Yeah, I think with a little more practice and trials, I will be fine. I bought two hole saws, so if I wear one out trying, then I still have one to do the actual tank. When I do drill the tank, I plan to lay it down on plywood of something to completely support the pane I am drilling, that should also keep chipping to a minimum.

As far as window pane glass, I work for a major window manufacturer and the glas is what we use to make the insulated glass you have in vinyl windows for your house. It is only 3/16" thick annealed glass, good thing is I get all the scrap I want to practice on. I figure if I can master glass this thin and fragile, I should be OK on an aquarium.

[Randy]

I didn't practice at all and it went ok. I did get some chipping (I'm not sure how or why), but the chips were on the exterior ... the non-sealing surface.

I hate to give a link to an outside forum, but here's my thread on an overflow I'm doing on a 75 gal:
Reef Central Online Community - Glass Overflow Question

I tipped the hole saw at an angle to start and rested it between my thumb and my index finger if you know what I mean. This gives you plenty of support. I highly doubt that you will need ANY support on the sealing surface considering that you will not have much if ANY downward pressure on the hole saw as you are drilling. Just let the saw do the work and it will be fine.

In the link shown above, you will see a pic of the worst hole I drilled. It chipped, yet didn't come apart ... kinda like an external fracture or whatever ya call it. This flaw was external and not at all tank threatening. I've seen much worse.

I only used a constantly flowing garden hose running in the direction of the cut. I did not use any putty.

GOOD LUCK and post some pics!

[flgoose]

I've drilled a lot of holes and no matter how little pressure you use near the end, it's bound to chip. here is how i finally solved the problem. I drilled 2 pieces of 1/4" plywood to fit the hole saw to use as guides. with a dab of silicone, i position the two pieces on both side of the glass so the holes line up. I drilled part of the way from one side than finished from the other. works every time without a single chip.

[Samper]

I'm gonna try that next time I drill.

Thanks flgoose

[Ratpack]

Do you just line them up by eye? I also assume that since they guide the hole saw, there is no need to start at an angle, correct?

[scubadude]

Nice tip goose....I like that idea too

[reseter5]

i did custom glass work for 8 years... tanks.. frameless showers.. mirrored bathrooms and so on... you cannot drill tempered... it will shatter into a million pieces... the best method to drilling a clean hole .. is simple....

1. use a round glass bit not a spear point type. spear point will work but not as nice
2.. you need to keep the drill bit cool and lubricated... cheap was .. water with a little antifreeze.. they do make water soluble lubricants for glass drilling..
3. drill from both sides.. half way through on one side and halfe on the other... this will eliminate the chipping out of the other side....
4. thicker glass is easier to drill thriough.. its more stable and strong.. it takes longer but comes out cleaner...

keep the bit cool and lubricated and you will be fine...... the cleaner the hole the better... a hole makes a weak point......... the more you do it the better you get... and as you are drilling ream the hole a little as you drill ... this will eliminate the bit from binding up and make a little room in there for it....

[Samper]

reseter how long can one expect a cheap bit to last? I've done about 8 holes with one and it still seems to be fine. Also can you recommend a good place to buy a good brand of various sized bits?

[120gallons]

Any recommend a good source for glass bits online?

[Randy]

Richon Tools

Very inexpensive and a VERY reliable company.

[flgoose]

Sorry it took awhile to respond to the questions, i've been working on my skimmer and it's been driving me nuts but that's another thread.

as for the questions, yes, i do lign up the plywood by eye. Actually i use a light from the bottom after placing one piece of plywood guide. That makes it so easy to lign up the second one on the other side. No there is no need to start drilling on a angle. Make sure you use water though. I tried the antifreeze mixture and frankly i didn't see much of a difference. I just use a hose and running water. Works good for me.

[reseter5]

sorry for the length it took for me to reply.... most round bits are diamond laced... as long as you keep the bit cool it will last a while... somaca.com is a glass industry supplier.... giid bits are over $100 each... i buy the cheap ones off line.. for like $25 for a 3 or 5 pack and use them till they die.... then replace them........

[onebadbug]

I own a glass shop in the far west suburbs here. In the years I have built scores of tanks, drilled thousands of holes and a million other things you can't even imagine to do with glass but there are also things you can't do as well.

So I will put my 2 cents in for doing holes in tanks.

1) Always have serious paintience thinking you are going to push a tube diamnond or grit holer through glass like you are simply drilling through a sheet of plywood will land you in disaster.... always take you're time!

2) About tempered glass, thinckness does not matter, once glass has been tempered it is what it is until the end of its life. Any glass that has been tempered cannot be:
cut,
edged,
notched,
bent,
and especially DRILLED THRU!
Tempered glass cannot be altered in any manner or form ever PERIOD!
if you do insist on attempting reguadless, then use a brick as a test bit and you might as well go order a new tank now.

3) A little common sense here and a bit of insight reguarding bit types...
---Carbide spear & Carbide prismatic style point bits
Don't even attempt to turn a hole through a pane of any thickness glass the chances of ending in a good result in anything larger than 1/8" dia. is about 1/50! ...unless you have been doing it for 20 yrs for practice!
---Diamond core or Grit Brass hole drills
These are you best bet and will ussually be the safest as well as make the cleanest hole possible
---DRILL RPM SPEEDS
Hole Diameters Up to 1" 900-1500 rpms
Hole Diameters up to 2" 700-900 rpms
Hole Diameters over 3" 500-700 rpms

4) The best practices to get the best results for the hole(s).
if you are using a drill press that is plugged into an 110v outlet abslutley make sure it is GFI and correctly working! If it isnt GFI then go to the hardwars and buy a GFI pigtail to plug into! SAFTEY FIRST!

---If you have access to a drill press with an adjustabe table this works great!

---If at all possible support the backside of the hole use a small block of wood with some thin carpeting on it and bring the drill table up to the underside of the pane/lite you are wanting to drill through to give it some support but not hard enogh to case upward deflection on it. This will greatly reduce on chipping, oystering and slug popping-down when you are at the last millimeter of actually cutting trough. And will greatly reduce the posibilty of breaking the lite itslef simply from stress.

---ALWAYS DRILL ABSOLUTLEY PERPINDICALR TO THE SURFACE! as well as some sort of device that will hold it.
if you don't have acess to a true drill press simple hand drill press setups are very easy to be gottn just about any decent hardware store or the one below was on ebay for a measly ten bucks

**I see people in fact, alot of people, using some of their "how to" practices on youtube and such showing them using a simple cordless drill trying freehand with a core drill, BAD IDEA!!!! If you notice you always see them ussually about halfway through their job and they are ussually going off on a diagonal as they go thru to cut the hole. And you ussualy see a plie of other new tanks behind them which says to me they own a petshop and can afford to kill a few tanks within their process. A diamond tube drill does not have a pilot to hold you centered, when you attempt the hole in this manner it is going to walk all over the place and will scatch around of where yo are working. Anywhere you put a scartch has the possibilty of being seen as a score around the hole itself anything that is a score though may not break in the begining will more than likely have a pretty good possibilty of breaking somewhere on that score in the glass somewhere along it life.

5) WATER! WATER! WATER! ...or coolant if you have access to it.
You need to keep it cooled, If you heat the glass with the bit or vice versa it it will cause heat fracture! ..as well as damage and/or kill the bits life. And also in the same token don't electrocute yourself either, if you are using a drill press that is plugged into an 110v outlet abslutley make sure it is GFI and correctly working! If it isnt GFI then go to the hardwars and buy a GFI pigtail to plug into! SAFTEY FIRST! How much water you ask?well it doesnt need a full out flood from a garden hose but enough of an uninterupted and complete contact and flood of where the drill is beng made. A simple way to accomplish this is with a simple O-ring. The O-ring will keep and allow enough water within the work area as it is streaming into it a simple lightly flowing sorce to the working area as you work.
**also plastic lids with the center sections cut out will also work well too.

6) FINISHING OFF THE TANK HOLE
Once is all said and done take some 120 or 220 grit emery type paper or round stick (the sticks work great but are a bit hard to find so an EZ around is to wrap some around a piece of doll rod about 1/2 the diameter of the hole itself) and go around the edges of both the inside and outside of the hole sand down to what we call a chamfer or aris on the edges to ease the sharper edges duller, clean and smooth, to remove any chips or small oysters there may be. A rule of thumb is to if you can feel any chipping around the hole with you're fingernail it can be a spot that can cause a run in the lite especially when you go to tighten a future theough it so remove as much of any of these as you can as best as possible.

7) if you are not confident of doing it yourself
then the best thing to do is to bring it to a GOOD glass shop and have them drill it for you. For a refernce as to what it might cost (and I am not asking anyone to bring it to me in any way shape or form) for us holes start at $22.00 for up to 1/2" and then go up $22.00 on increments of 1/2" up to 6" in dia. If someone is quoting you &75 to cut a 1" hole in you're tank then keep calling down the phone book until you find one that isn't a sheister.

And the last thing to consider if you are bringing it to someone to have it drilled for you the Glass Company will never and cannot be laible of you're tank as glass is glass and even the best equipment can still break your or anyones glass this is just such as life is in the glass buisness. But in the 30 or tanks I have drilled for customers, and ussually as they wait, over the years I have never broken one of them as of yet.

[Ratpack]

Thanks onebadbug, great info. Maybe you can answer another question I have about drilling glass. How close to the edge can you drill and how much space minimum between holes?

[onebadbug]

Thanks onebadbug, great info. Maybe you can answer another question I have about drilling glass. How close to the edge can you drill and how much space minimum between holes?

As a general rule of thumb I use this....

As for distances between openings:
take the holes diameter and multiply by 3
*if you have a need to get closer make sure bulkheads don't interfere with eachother
**if you are working with 1/2" thick and up you can fudge a bit closer and still stay safe as long as it is not on the floor of it as the web will now be the least strong area...

As for distance from edges:
For More Loaded stress areas within the tank no less than 2" from any 2 edges.
For Less loaded stress areas within the tank no less than 1" from any 2 edges.

a point worth remebering if you attempt multiple holes in sequence across one lite... The first will be the easiest, the second gets harder the third will be by luck and you more than likely won't get thru hole #4 without buying a cheap $2,200.00 drill press that is designed to do nothing other than drill holes in glass. And bits are around $300.00 for each sized bit.


Hi all..

I used to be into salt big about a decade or so ago and am thinking of getting back into it as of late. IF I do I will be making another new tank again seeing as I own a glass shop soo... Hiaya!

The only reason I got out last time..? Loooong story so I'll make it real short...

500+ gallon reef tank
15 year collection of animals & equipment
120 year old oak tree
Tornado out of season
STATE FARM SUCKS!

Nuff said?

[Ratpack]

Can you elaborate on why it would be harder, themore holes you drill in one pane? Is it because the bit needs time to cool, gets duller (obvious, but hopefully not after 1-3 holes) or from a physical standpoint of being tired and rushing?

[Ratpack]

Oh, one other idea I would like feedback on. I have practiced starting the bit at an angle and it works pretty good, but still leaves room for error. It was suggested that I use and inside angle such as a framing square to hold the saw in place and then I can start with the bit flat on the glass. What do you folks think?

[onebadbug]

Can you elaborate on why it would be harder, themore holes you drill in one pane? Is it because the bit needs time to cool, gets duller (obvious, but hopefully not after 1-3 holes) or from a physical standpoint of being tired and rushing?

If it is a decent quality diamond and/or carbide coated core drill as long as you don't burn it you should expect to punch 20-30 good holes before it gets tired and need retiring. If its a cheap one? you'll know it... it will either toast itself in 5 minutes or toast you're pane or both.

For each hole you drill in sucsession around the working area will make it less and less forgiving, especially when it comes around the "web" (that is the left thin areas between previous holes and edges).... In other words where you set the drill for the first one you better make sure you have a place to rest on for working on the next one and so on.... and when you do holes side by side they like to oyster towards the direction that is facing the prvious hole
I call it the swiss cheese effect...

Glass is a fragile product to begin with from the get go and each step of fabrication will have a higher percentage for failure as it proceeds. I'm not saying not to do or attempt it, if you are confident then have at it and just remeber... it's glass and sh1t happens

Oh, one other idea I would like feedback on. I have practiced starting the bit at an angle and it works pretty good, but still leaves room for error. It was suggested that I use and inside angle such as a framing square to hold the saw in place and then I can start with the bit flat on the glass. What do you folks think?

when you have to start at an angle you are setting up for disaster... The reason you see every one doing it an angle is because the fact it is almost possible to center and hold a stationary position that is spining and has nothing to hold or guide it to start it! Go & Buy a cheap vertical hand drill press... they have them at home depot or lowes for about 20-30 bucks and then strap a simple cordless drill to it will make it go so much nicer in the end....