notching tank for external overflow
 

Ok, I remember people drilling there tanks with a dremmel a while back, how thick was the glass what bit did you use and what speed did you run the dremmel at?

I am thinking of getting a tank but I want to take a notch out for an external overflow and I am wondering if this is something I can just do my self. also is there any other way to do it, like a belt sander with a special abrasive?

Steve

re: drill glass with dremel, last hole I did was spd position 7 or 8 (out of 10) 1/8" round/ball bit, with 1/4" glass and about 7 linear inches and took ~ 20 minutes

Do you have the spreadsheet for slotted weir fr reefs.org? It's an Excel spreadsheet in their download section. You put in the number of openings and width and gives height and gph.

I use the 1/8" straight bit on high speed and have cut glass up to 1/2" thick

thats alright, but I am not doing a weir, just going to make a cut out, to much work to make a weir hehe I am actualy thinking of a 8 inch long and 1" down from the top, so acording to there sheet It should be able to flow 2000gph

so for the ball and the 1/8th dermmel bits are you guys just using the high speed steel ones or an abrasive one?

Steve

Used the diamond encrusted bits (just picked up another pack (30 bits) today fr PA for 4.99). Didn't get it but was also looking at a diamond wheel about 1.25" dia, not sure if it's just for cutoffs, grinding or if could be used for grooves.

The spreadsheet is neat that you can put in 1 opening.

Ok, cool.. I will have to get some junk 1/2" and do some cutting on it to see how it works so I know what I am in store for. what did you do for cooling? I am thinking if just haveing a hose running gently where I am grinding.

Steve

A small stream of water would work and if was warmer outside probably would have done that myself but since was in the basement just made a dam. I used duct seal, it's a putty used to fill holes when running wires and pipe but could use play-dough etc. Just kept cutting the groove a little deeper not going all the way through so wouldn't loose the water until the end. With a continous stream wouldn't matter if cut through and would be able to follow line better (not blocked by cuttings).