Just how long does drilling usually take?

[Gorgok]

Im drilling 60mm holes in 8mm glass and this last hole took over 3 hours... User error or is glass just that damn hard?

I have a drilling guide of sorts so im not even holding the drill anymore, but its also not pressing down with much force as a result (just about the weight of the drill only). Im not going full speed either, probably around 1500 rpm (half the max of the drill) but sfm wise thats around 1000... Should i change speed/force? Something else wrong?

 

[IPT]

Lol, it take forever. 3 hours seems like a long time. I just drilled a 120 (1/2 I think) and all three holes took less than 3 hours. I know they say let the weight of the drill do the work but that takes f o r e v e r. I add a little pressure, not a lot. RPM wise I go middle of the road. It technically grinds through not cuts. Be really careful when you're going to break through too.

My 3rd hole took a lot longer than the first too. Not sure how long these bits last but I chalked it up to the bit wearing out some. Sorry don't have a specific time for you.

 

[muttley000]

Shouldn't take nearly that long, is it a new bit and did you keep it flooded with water?

 

[Gorgok]

Shouldn't take nearly that long, is it a new bit and did you keep it flooded with water?

Its not new, has a few holes done with it already. Its still got a good surface though, at least appearance wise i can see the diamond studding it still. I think its just a lack of pressure with this jig, as i don't think my other holes manually took much more than an hour total...

4 more holes to go, hope its not a half day of that noise.

Cutting 8mm glass with score and tap took way less time than this, heh.

 

[Matthias7]

It took me about 20 mins to drill a 20 gallon

 

[zeebies]

2 drain holes for 1" bulkheads on a 40 breeder took me 50 minutes per hole. Used a new BRS hole saw. Went very slowly on purpose - wasn't taking any chances.

 

[BeanAnimal]

Goodness... I plow through holes in a few minutes each. The critical part is starting the hold and easy off before you go through the other side. 3 hours is way too long.. 10 to 15 minutes would be reasonable if you are taking it easy.

 

[toothybugs]

Goodness... I plow through holes in a few minutes each. The critical part is starting the hold and easy off before you go through the other side. 3 hours is way too long.. 10 to 15 minutes would be reasonable if you are taking it easy.

Yea, I was going to say "Geez, the 2.5 inch port on my 40 took me 10 minutes with a diamond-tipped Dremel bit." 3 hours is a very, very long time.

Make sure you are flooding your cut/ grind area with water, it will help immensely. There are a few good ways to do this. Ask if you aren't sure.

 

[mcgyvr]

yeah took me about 2-3 minutes to go through 10mm glass.. and I felt that was going slow..

 

[laga77]

Your bit is worn out. It was cheaply made with very little diamond material and/or poor bonding of the diamonds. The bit I bought from a ebay seller lasted 5 holes and was toast. With 35 years of concrete work I used hundreds of diamond blades and bits. They last so long and then you are just rubbing metal on glass. In fact, if you were to take a new bit and try to put in a hole that was made with a worn out one, it would be very snug or not fit at all.

 

[GroktheCube]

Sounds like the bit is dull. When I'm doing holes that "matter", I use a bit for one or two holes.

 

[m0nkie]

drilled using the new glass-hole drill bit..

first 3 holes took 15minutes.. last one took a good 25min..

 

[Kyuss]

I don't remember exactly but I'd say 5-6 hours. Admittedly I went slow because I never had done it before and the glass on my tank is quite thick. There may have been a few beverage breaks in there.

 

[Gorgok]

I did my first few holes with a cordless drill and got really annoyed at replacing batteries. I don't know how long those holes actually took, but i imagine it was much less than that last one. Only with this setup do i actually see how long it takes at a constant pace.

But i take it from the majority that the bit is indeed shot, and have ordered a new one.

 

[James77]

I drilled 3 holes in the back glass of my 120, each one took maybe 4 or 5 minutes, that was with a new(but cheap) bit.

If it is taking hours, there is something wrong.

 

[James77]

Your bit is worn out. It was cheaply made with very little diamond material and/or poor bonding of the diamonds. The bit I bought from a ebay seller lasted 5 holes and was toast. .

Yup....you get what you pay for. The cheap-o bits off ebay and the like are great for a couple holes....but nothing beats a quality diamond cutting blade

 

[Ser Davos]

Im drilling 60mm holes in 8mm glass and this last hole took over 3 hours... User error or is glass just that damn hard?

I have a drilling guide of sorts so im not even holding the drill anymore, but its also not pressing down with much force as a result (just about the weight of the drill only). Im not going full speed either, probably around 1500 rpm (half the max of the drill) but sfm wise thats around 1000... Should i change speed/force? Something else wrong?

I drilled my 125 the other day using a bit from glass-holes and it took me about 15 minutes per hole. I thought that was slow... 3 hours per hole is crazy.

 

[Gandolfe]

I bought a $14 bit off ebay and drilled 10 1" bulkheads in my 125( 1 return,3 overflows, 2 closed loops w/3 holes each) and 2 more holes in 40 gallon breeders for a sump and a macro tank, and I didn't even use that much water while drilling. Used a cordless drill and a Plexiglas template to start holes then high speed until almost through. Made sure glass was supported while drilling. Only had a few chips in the first 2 holes I drilled (until I figured out how to do it right) Main thing is not to rock drill at all while drilling( this is what caused the chips)....I drilled all 10 holes in less then 2 hours

 

[Gorgok]

I ordered a ~$8 bit off amazon with free 2 day shipping, and finished my 4 holes in under 30 minutes i think (thats including the time to move the guide and setup the next hole). First hole the bit basically fell through the glass under the weight of the drill in the guide, which was pretty amazing to see. Obviously my bit from BRS was never in great shape, as it was never fast... i would not have made a guide if it went that fast with a cordless drill. Would not even have had to swap batteries except after maybe 3 holes (instead of multiple times per hole).

I wonder if the original bit got damaged in shipping or something... Anyway i could have bought 3 of these new ones off amazon with free 2 day for the price of the one from BRS... Walls are thinner so it won't last as long (less surface area for diamonds on the bottom) but it will also cut faster (less material to remove). 4 holes seemed to be the point on this new bit where it started to slow though, but i was done with my holes after that 4th one.

At least i learned something. A good bit is really quite fast.