260 w/ BTA "Island"

[Timfish]

And so it begins . . . 

[Timfish]

Making a big hole in a perfectly good tank.

 

I'm stting this system up with a low profile drain offset to one side away from from the back.  Since it won't have a side to attach it to to keep it in place and a lot of rock setting on top of it, I'm adding a second sheet of glass on the bottom to add additional strength to the bottom.  

 

I prefer to start by making a wood template or jig.  Jigs will keep the bit in place and stop it from "walking".  If drilling multiple holes a jig helps keep all the holes aligned also.  The diamond bit works just as well with wood as glass (no water is required to cool it 😁 )  

 

Sometimes I'll use clamps (use wood on both sides of glass to protect it) but most of the time I use weights to hold a jig in place while drilling.

 

Glass with hole.

 

Silicone and setting the reinforcing piece in place.  After it set up a few days I went around the edge with more silicone.

 

Drilling out the bottom.  To keep the bit cool I added about 1/2" of water.   The tank is stitting on a hydraluc cart, to help keep the bit from chipping when the bit broke through I placed several layers of cardboard compressed under the location of the hole.  The cardboard also helped keep  water draining out to a minimum after the hole was completed.

 

Checking to make sure I drilled the right size hole. 😄