DIY Glass Overflow

 

The Basic Design:

 

    Silicone Shown In Red
 

 

    This glass overflow is for my 75 gal glass aquarium. I wanted to make this overflow installation as simple as possible and without much expense.

 

Step 1~ Fittings For The Overflow

    I chose to use two 1-1/5" bulkhead fittings from The Filter Guys. I also used two 3/4" Banjo bulkhead fittings from Grainger. The 1-1/2" bulkheads will be for the standpipes and the 3/4" bulkheads will be for gravity feeding other equipment like my protein skimmer, UV sterilizer, etc...

1-1/2" Bulkhead   3/4" Bulkhead
 

    Most of the time there's not a wide variety of 1-1/2" fittings at local hardware stores. This made it hard to find a 1-1/2" Street Ell so I decided to make one instead ... and a more compact one too!

Male Adaptor and 90° Elbow   Male Adaptor
and 90° Elbow Assembled
 

    My intention is to make this overflow as compact as possible. As you can see in the pictures above, these fittings are just too bulky so I cut both of them down as short as I could using a Miter Saw. I then glued them together using PVC Glue.

Cut Fittings   Glued   Measurements
   

 

    I'm making 2 Durso Standpipes using 1-1/2" sch 40 PVC pipe and fittings. I will be making them as compact as I can so they take up as little space inside the overflow as possible.

    First I cut the 1-1/2" Tee and the 1-1/2" 90° Elbow using a Miter Saw. When I glued them (using PVC glue) I used a rubber band to temporarily hold the fittings together as the glue dried.

Standard Fittings   Cut and Glued   Comparison   Finished Compact
Durso Standpipe
     

    Many might ask "why not just use a Street Ell with the Tee"? 1-1/2" Street Ells are not too common and this option will make a more compact Durso.

 

Step 2 ~ Drilling The Glass

    I purchased the Diamond Hole Saws from Richon Tools.

    I kept every hole that I cut at least 3" from any edge of the glass and at least 3" from any other hole. You just want to make sure that your holes are mapped out to ensure that all of your fittings can be spun 360° without hitting anything once they are installed.

Drilling:
 		   Here's The Placement And Measurements:
 
   

    My first attempt at drilling the first hole was frustrating! I drilled entirely free-hand using a cordless variable speed drill. I did not practice at all, I just went straight to it. I placed a running garden hose on top of the glass.

  1. When you are about to drill your hole make sure that the water is running and place something inside the tank to catch the piece of glass that falls through!
  2. Support the hole saw using the base of your index finger and thumb (above the abrasive portion of the saw). If you do not support the saw then the saw will drift like crazy causing scratches like this. Like I said ... it was frustrating in the beginning.
  3. Slightly tilt the hole saw toward your hand and begin to drill. This will crate a groove that will guide the hose saw. Downward pressure is NOT necessary!
  4. Once the hole saw has created this groove, you can begin slowly leveling out the hole saw. This will create a groove all the way around and you can stop supporting the saw with your hand. DO NOT force or push down on the hole saw.
  5. Just continue cutting and use a steady flow of water toward the saw (a helper is always convenient).
  6. When you're nearly through the glass just take it easy or else you'll chip the inner face of the glass which is your sealing surface for the bulkhead fitting. You do not want to chip the inner surface.
  7. Thoroughly rinse the tank inside and out. Cutting glass creates quite a bit of very fine glass shavings and we do not want any remnants in our finished tank.

    When my holes were finally cut it looked like this:

    This was the worst one
 

 

Step 3 ~ The Glass Plates

    It is important that you make sure that you choose the dimensions of your glass while bearing in mind that one day you 'may' have to remove or replace your fittings in the future (including your bulkheads). You want to make sure that there is enough room inside your overflows to do this.

    I purchased 2 pieces of 1/4" thick glass from my local glass shop. I had them cut it 18-3/4" x 15-1/2" and bevel all edges and they charged a total of $21.18

    I thoroughly cleaned the back of the glass using a rag and Xylene (solvent) to ensure that it was completely clean and degreased. I masked all the way around the edges and propped them up to be painted.

UPDATE:
    I used 4-5 coats of 'Semi-Flat Black Krylon' spray paint  and it all peeled off after a month or so. DO NOT USE SPRAY PAINT on the interior of your overflows. Sorry, at this time I have no input on what type of paint should be used.

BEFORE:   AFTER:
 

 

Step 4 ~ Silicone The Glass In Place

    Make sure that the glass and all crevices are dry. I blew out all excess water using an air compressor.

    Make sure that your glass is plumb and level when you do this. I used a square to make sure the glass was set 90° vertical,  I used a tape measure to ensure that the glass was level with the top of the tank, and some masking tape on top of the glass to temporarily hold it in place.

    While the glass is held in place, squirt out several (or more) small dabs of silicone into the seams and allow it to dry. Try not to make a mess with this step.

    This will hold the glass somewhat firm. Once this silicone is dry you can mask both sides of the seams.

    Now you can apply the primary sealing bead of the silicone and remove the masking tape while the silicone is still wet.

FRONT:

  

BACK:
 

 

Step 5 ~ Paint The Back Of The Tank

    I used paper and blue masking tape. I sprayed on approx 6 coats of Black Krylon Semi-Flat and used a fan to quick-dry the paint.

Masked:                
       

 

 

 

Once the tank is up and running I'll Post More Pics

 

 

 

 

 

Hit Counter