Enlarging holes in tank

dallasg

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Hi Hennie,

if my tanks already have holes drilled, 40mm and i want to make them 50mm, can i drill over them with the bigger bit?

thanks
Dallas the sandtonian :)
 

Awvince

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That does not sound safe, but i'll tag along to see if it can be done. :)
 

Tobes

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Hi Hennie,

if my tanks already have holes drilled, 40mm and i want to make them 50mm, can i drill over them with the bigger bit?

thanks
Dallas the sandtonian :)
Not sure because a hole saw has a bit in the centre to centralize it. With the hole being 40mm, how you gonna centralize the 50mm saw to keep it from running around? You can always use a small dremmel tool and grind it bigger(which will take forever) or cut it with a thin dremmel tool all around the circumference until you're through (I did this with 12mm glass) - also takes forever :p
Just remember to use a lot of water on the tool ;)
 

Mike

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You can clamp a piece of flat timber over the current hole, then drill through the wood and into the glass, the wood keeps the glass cutter from slipping - do it slowly and keep wet, it will be fine.

P.s. - i tried with a dremel, it took bloody ages. :(
 

Tobes

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You can clamp a piece of flat timber over the current hole, then drill through the wood and into the glass, the wood keeps the glass cutter from slipping - do it slowly and keep wet, it will be fine.

P.s. - i tried with a dremel, it took bloody ages. :(
Great idea Mike - done something simular before but with steel - not glass, why I didn't think about it now is beyond me. Took me 6 hours with a dremmel on 12mm glass (was also playing with the wife inbetween as she sprayed the water :whistling:)
 

Mike

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Great idea Mike - done something simular before but with steel - not glass, why I didn't think about it now is beyond me. Took me 6 hours with a dremmel on 12mm glass (was also playing with the wife inbetween as she sprayed the water :whistling:)
I'd love to take the credit, but it is a fellow reefer that showed me how to do it:)
 

dallasg

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Great idea Mike - done something simular before but with steel - not glass, why I didn't think about it now is beyond me. Took me 6 hours with a dremmel on 12mm glass (was also playing with the wife inbetween as she sprayed the water :whistling:)
hahaha :)

thanks mike, will do that
 
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The glass drill bit does not have the centre drill piece in it...Do what mike has suggested just go realy slow and dont rush it
 

dallasg

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cool thanks, going to be fun moving a 150kg tank to drill it
 
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The glass drill bit does not have the centre drill piece in it...Do what mike has suggested just go realy slow and dont rush it
Yup, I agree

Of course, the safest bet would be to do the drilling using a drill press, to prevent the drill from "wandering" off centre, but with a really steady hand you just might be lucky...

Hennie
 

dallasg

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cant move the tanks, so will have to see if i can modify a router to drill and use its big base to steady the drill
 

dallasg

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ok just to recap, i need to drill 20mm and 50mm holes my tanks.
can i drill in the base say 5cm from the edge?
i have made hole templates for enlarging the holes, going to use diamond hole saws, to keep them from wondering sound ok?

now my worry is that these can weaken the tank, but if i add a square piece over the hole like this, courtesy of punk

DSC01045.gif
 

Mike

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%cms from the edge is ok, just don't drill the holes too close to each other
 

dallasg

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cool, need to drill 2 in the center about 10cm appart and thats all :)
 

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