Step-by-Step: Drilling Holes in Your Glass Tank for Bulkheads

[dvincent]

Originally posted by jamesBS
has any one ever drilled a tank with water in it.i have a 90 Gal that I want to put a anther drain in. I wood drain down a third and have at it.do you think glass dust will hurt corals.its just sand right

I drilled my 180 for an 1 1/2" bulkhead after it had been set up for 8 months. Just drained out about 30 pct. and started drilling, as for the glass dust di not bother the inhabitants just made the water cloudy for a few hours, and remember glass is sand.

[Willy315]

Originally posted by BraenDead
Some tips I thought I would share after drilling lots of small holes in my 75g (8mm holes drilling slots for an external overflow).
- Using a drill press is easiest, but if this does not work, I recommend using a cordless drill. I haven't found a corded drill which offers good enough speed control.
- Do not drill at fast speeds, use slow. I used 600 rpm on the drill press and use a cheap cordless drill (6.8V) that does not go very fast either. Using a corded drill was hard to control the speed and went WAY too fast and did not produce a good smooth cut.

- My technique:
1. The best way to start a hole without any slippage is to make a guide for the hole. I use a small piece of acrylic with a hole drilled the same size as the drill bit. I recommend not using the same bit as you may wear-out some of the diamond dust from the bits. Use this guide to drill your hole by either clamping it in place, or if you can not clamp it, you can put a small amount of plumbers putty to form a thin sheet on the acrylic to keep it in place on the glass. You only need to use the guide for a little bit until you have cut away enough for the bit to fit in without sliding around.

2. I tried dozens of methods trying to eliminate any glass knicks and shards from happening while the bits goes through the back side. Using duct tape on the back side works alright, but you will still get some knicks and shards. The best way to eliminate this is to start drilling one side as described above in #1. Once you have gone a little bit, remvoe the guide and do the same process on the back side of the glass. Make sure to line the guide up so it lines up with the front side where you started to drill and do the same process. Drill at least 1/16" deep on the back so that there will be no shards or pieces that break away once you finish the hole. I have found that I did not need a water dam by keeping the drill bit wet with a spray bottle every 5-10 seconds (drill for 5-10 seconds, stop drilling to spray off bit, then drill another 5-10 seconds). 1/16" shouldn't take too long to drill.

3. After drilling the back I recommend putting a piece of duct tape to keep the piece of glass from falling. More importantly, I found that occasionally the drill bit would get loose in my cheap cordless drill. If the bit is loose, you dont want it coming out and falling through the hole.

4. After drilling the back, finish with the front. Initially, I used water dams to hold a lot of water but I found that I did not need a lot of water to keep it cool. This added a lot of time and was a mess to do (especially with the 70+ holes I drilled). I found all I needed to do was keep a small puddle of water where I was drilling the hole. Monitor the bit while you are cutting by feeling the bit and the glass to make sure they are not hot. If they are noticeably hot, you need more water or maybe you should just use a water dam (my holes were much smaller than what others may be).

Hopefully these tips will help out.

Bob

I drilled 3 holes in my 75. After I got done I figured one way to keep the glass from "splintering",would be to clamp a piece of glass on the back side of the hole you are drilling to keep the bit from "busting" through... Just a thought....also i rounded all the edges of all 3 holes with sandpaper, made for a very nicely finished hole with no sharp edges.

[BraenDead]

I tried clamping a pice of acrylic to the backside thinking the same thing, but this method produced the most splinters of all the methods I tried. Perhaps it would be different with glass, but I did not have good results using that method.

Bob

[DHyslop]

Bob,

Not all tanks that have been cut for slots in the back have failed. Yours are widely spaced and you seem to have put quite a bit of attention into mitigating these risks. IIRC I haven't read of anyone cutting individual slots in the rear of a tank, all the failures were one wide slot.

Level the stand in the garage or in the basement (near a floor drain!) and test fill it for a couple weeks. I don't have any links handy, but the failures I mentioned were posted within another thread (I think one of the very first threads on the topic).

I clamp glass behind when I drill for bulkheads and it works great (didn't really need it with my slots).

Dan

[Skorpinok]

Are there any posibility in using a dremil to cut out a hole big enough to fit a 3/4 pvc tubing. Kind-a like drilling a hole for a door knob? Do they make a diamond tip?

[jamesBS]

dvincent thanks for the impute I'm going to do mine this weekend

[Spuds725]

Originally posted by To-Arbitrate
Are there any posibility in using a dremil to cut out a hole big enough to fit a 3/4 pvc tubing. Kind-a like drilling a hole for a door knob? Do they make a diamond tip?

This guy didn't drill it for a bulkhead but dremmelled holes in the side of his tank for and external box... lots of pics and he describes how it was done... should be able to be done for a bulkhead too... I'm certain there is a thread somewhere here on doing it for bulkheads-- this thread should cover the basics of dremeling a tank-- just trace out the bulkhead and I would drill holes on your traced line and then connect the dots.

here is the thread...

http://reefcentral.com/forums/showth...hreadid=534878

yes they sell diamond edge dremel bits.. look at HD, Lowes, Menards, Ace, Sears, etc...

http://www.mytoolstore.com/dremel/dmdbits.html

[Willy315]

Originally posted by Spuds725
This guy didn't drill it for a bulkhead but dremmelled holes in the side of his tank for and external box... lots of pics and he describes how it was done... should be able to be done for a bulkhead too... I'm certain there is a thread somewhere here on doing it for bulkheads-- this thread should cover the basics of dremeling a tank-- just trace out the bulkhead and I would drill holes on your traced line and then connect the dots.

here is the thread...

http://reefcentral.com/forums/showth...hreadid=534878

yes they sell diamond edge dremel bits.. look at HD, Lowes, Menards, Ace, Sears, etc...

http://www.mytoolstore.com/dremel/dmdbits.html

Using a hole saw will give you a far better finished product. Using a dremel to cut out a hole CAN get ugly.. just my 2 cents

[Spuds725]

I agree- for the price you can purchase a hole saw-- I wouldn't even consider dremelling.... but I was answering the question... yes it can and has been done..

[brad23]

Ok what size holes do I need to feed a Dart for closed loop, can I get away with one or do I want two?

[dtaranath]

regarding the hole saws from lau on ebay, how many holes can each saw produce? My plans are for 5, using the 45mm saw. Would this be reasonable?

[swedish steel]

dtaranath - be sure to convert the bulkhead hole to mm to get the correct hole saw size. Bulkheads require different hole sizes based on the manufacturer. My original order for hole saws was incorrect due to not taking this into account. For instance, a 1 inch bulkhead requiring a 1 7/8 inch hole is equivalant to 47.625mm. One inch equals 25.4mm. I would test drill in scrap glass and try the bulkhead for fit or at least compare the bulkhead with the actual hole saw before drilling. I just got the three bulkhead sizes I will be using and the new hole saws I ordered from Lau should arrive tomorrow or soon after. My 130 and 300 will soon have holes in them.

[dtaranath]

Originally posted by swedish steel
dtaranath - be sure to convert the bulkhead hole to mm to get the correct hole saw size. Bulkheads require different hole sizes based on the manufacturer. My original order for hole saws was incorrect due to not taking this into account. For instance, a 1 inch bulkhead requiring a 1 7/8 inch hole is equivalant to 47.625mm. One inch equals 25.4mm. I would test drill in scrap glass and try the bulkhead for fit or at least compare the bulkhead with the actual hole saw before drilling. I just got the three bulkhead sizes I will be using and the new hole saws I ordered from Lau should arrive tomorrow or soon after. My 130 and 300 will soon have holes in them.

Thanks for the heads up. I double checked everything, and the 45mm saw works nicely with my 1 inch bulkheads (the bulkhead fits in the hole saw itself). I'm just concerned that I may not be able to cut 5 holes with one saw. I think I should be able to, but that's why I asked the question. Any thoughts on that?

[DHyslop]

Don't worry...I've done 7 holes with my 45mm Hong Kong special

Dan

[grendl]

I had some jagged chips where I drilled my tank... Do you all sand these down, or just leave them?

Trav

[DHyslop]

You'll generally have some slight conchoidal fractures along the rims. Slight is the key word here, if you're doing it right they shouldn't be very big. The worst ones are usually associated with the bit coming through the other side, which is why I like to clamp a piece of scrap glass on the other side.

Dan

[grendl]

Yeah, thats where the one good sized chip is, on the inside of the glass where the drill came thru. If its not going to make a difference to sand it, or leave it.. then I am just going to leave it. Opinions?

[Willy315]

Originally posted by grendl
Yeah, thats where the one good sized chip is, on the inside of the glass where the drill came thru. If its not going to make a difference to sand it, or leave it.. then I am just going to leave it. Opinions?

I read somewhere thast you want to sand the holes to help prevent cracking , I'll see if i can find the website that states that

Read the bottom of this page

http://www.northcoastmarines.com/bulkhead_fittings.htm

[zeblisik]

So I drilled my first hole!

I bought some drill bits off ebay from hongkong dealer lau

48mm and 38mm for 1.5" and 1" pvc parts though the 48 mm is a little snug it still turns inside the whole easy enough.

I used a scrap piece of glass I had lying around, for a coolant ring i cut the top part of a cd spindle(too big for use on a tank but ill find something smaller), used water, and started drilling w/ a cordless.

at first it skipped a lot so i made a 1/3 moon groove first, it worked out well.

its really easy, esp after the groove is made. i cant believe i paid 25$ for a lfs to do it.

[Willy315]

I used a 60mm hole saw for 1.5" schedule 40 bulkheads and a 35mm for 3/4" scedule 40 bulkheads. both gave a great fit

[BallaBooyeaH]

WOW - what a link.

I need hole for a closed loop I need for a 4 way which I first plumbed wrong. It would not work due to to many bends and this lost all my head oreasure. So I need to Drill. I was looking at having to pull the pane of glass out and sending it to get drilled - looking at over €100 for this to be done then would have to put it all back together.

Gonna order from Lau and get the bulkheads I need first.

Quick question, I was looking at bulkheads from this supplier - http://www.coralculture.co.uk/shop/i...?cPath=157_159 they have a 32mm tank connector which is the size of my plumbing. AM I better off getting the Savoko fitting? Just want to make sure that I get 32mm clean through the glass.

Thanks again for this thread - RC rocks.

[zeblisik]

Balla booyeah,

i dont know about that... i just use male and female pvc connectors w/ washers/gaskets/orings to make it waterproof

[piranhaking]

i know that this hasnt come up for a while, but i think the antifreeze on the cuts would be more for lube than heat. If youve ever felt it, it is rather slippery.

[JustOneMoreTank]

Glad everyone is still enjoying the thread and getting useful information out of it. RC is a great resource.

[zeblisik]

why would you want to use lubrication? I mean, the diamond coated hole saw cuts through the glass by virtue of scratching it, that is, contact, friction.. no?