Drilling overflows in rimless tank

[kenc87]

I've drilled a tank before using a glass holes kit and found it to be very straight forward, I plan on purchasing a rimless tank soon and will also be drilling this tank. My only concern is that the prior tanks I've drilled had a rim to use as a guide, on a rimless what do you guys recommend to ensure my overflow box ends up being level seeing as I will have two 1" drains

 

[Maivortex]

Make a template out of acrylic then duct tape it to the tank

 

[kenc87]

That's not a bad idea, I would have to source some acrylic and another hole saw but definitely an idea worth trying

 

[racer2438]

You can make one out of a piece thin wood and do the same thing..

 

[sleepydoc]

+1
I made a guide out of a piece of ¼" hardboard. You really only need it for the first 30 sec of drilling. Then the bit has made a groove and won't wander.

Clamp a piece of wood to the back side too to minimize chipping. If you can drill from the inside out it helps, since most people have the flange and gasket of their bulkheads on the inside, a few chips on the outside are less of an issue.

 

[NanoReefWanabe]

+1
I made a guide out of a piece of ¼" hardboard. You really only need it for the first 30 sec of drilling. Then the bit has made a groove and won't wander.

Clamp a piece of wood to the back side too to minimize chipping. If you can drill from the inside out it helps, since most people have the flange and gasket of their bulkheads on the inside, a few chips on the outside are less of an issue.

agreed, though clamping wood to the back of the hole should pretty much remove any risk of chipout if you are using water, a good bit and proper pressure.