# Rimless tank builders/ owners unite for critiquing!



## jaidexl (Jan 20, 2007)

Of course, you are welcome to chime in even if you're not a builder but still have some knowledge to share. I'm diving into the tank building game head first now that I have a source of free glass. Anyone see any problems with the drawing below? *(see updated drawing in post#4)*

Here are a few of the questions on my mind at this point...

1. Bulkhead hole size? How far in from back glass to allow for BH fittings?

2. With 3/8" glass, is it exactly 3/8" subtracted from the edges of insetting panes and bottom glass? (will be a floating bottom)

3. Is it necessary to edge the corners of the bottom pane even if it's floating? Will the bevel add any strength to the bond or is it wiser to maximize the contact area by not edging/beveling the edge? (all seams will be pressed with black GE RTV between) My glass cutter adds a nice rough texture to his edges somehow, which I imagine can assist the bond, might it be wise to do this to the bottom pane as well?

4. It's been said elsewhere to not press all the silicone out of the seems. How small of a gap is too tight, 1mm, 3mm, more or less maybe?

5. Is 3/8" glass sufficient for allowing adequate contact area at corner seams while keeping bowing at a minimum on an 18hx24L" pane holding ~40 US GL? Would 1/2" glass be overkill?

Note- Yes, I've read Scolleys' build on PT (both threads) and if my Qs are answered there then I really don't remember them exactly, nor do I really want to skim back through all those posts to find them. :faint2:










Note- bulkheads (in/out) will hide behind center/rear hardscape, lengthened and adjusted w/ flexible ball socket tubing.


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## hoppycalif (Apr 7, 2005)

If I recall correctly, glass is supplied in metric sizes, with 3/8" being 9 mm, which is closer to .35" than .375".


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## jaidexl (Jan 20, 2007)

Thanks Hoppy, very helpful.

So 3/8" glass is more like 23/64" or a little less. Now I just need a few answers as to how much space to leave when pressing the seams and I can hopefully apply that info to achieve more flush corners.


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## jaidexl (Jan 20, 2007)

Ok, in light of the info given here and at PT, I've converted the critical measurements to metric.

The bulkhead measurement was not converted because it's not critical and there's no reason he can't mark it off in inches with a tape measure.

The starting height and width were rounded to the nearest cm to keep things easy.

The total subtraction from insetting panes allows for a 1.5mm sealant gap (just under 1/16").


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## FishandTurtleJunkie (Apr 14, 2007)

Maybe someone with a decent size ADA tank can shime in on bead size. I wouldn't bother edging the inside bottom edge. First, you are taking away that much more material that the silicone could be adhering to, and second, it is just extra work for you to prep something that will never be appreciated. Just my .02 worth.


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## fwfan (Mar 11, 2008)

a few thoughts on the subject..
As far as adequate thickness, 3/8 is more than enough. For 24"x18" panes you would probably be more than safe even with 1/4 (I have a 35 gallon that is 36x18 done with 1/4). You can go with 3/8 if it makes you feel more secure, but if possible check with your glass guy to see it before hand. I have glass cut for a 5 ft L x 24" h tanks made from 3/8 and it even surprised me just how heavy duty it is. You can check this for reference http://saltaquarium.about.com/cs/aquariumdiy/l/blcustomtank.htm 
Second, double check with your glass guy. 3/8 is actually closer to 10mm. Ask yoru glass guy if you specify 3/8 if he will end up with the 9 or 10mm. not that it makes a big difference, its less than .025 either way. I made a 16x12x18h tank based on plans for 1/4" which was actually 6mm with no noticeable discrepincy on the edges.
third- pressing the silicone. You needn't need to worry about pressing silicone out of the joint. Run your bead of silicone and press the pane firmly in place to seat it the weight of the glass will do the rest.


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