# diy spray bar



## freelanderuk (5 Aug 2014)

I have just made 2 spray bars and have a slight whistling, not to loud but loud enough to be annoying.
I had read a thread on here about drilling the holes larger , not all of them but just a few at one end of the bar to keep the velocity, I have searched and read most of the spray bar topics but can not find the information, can anybody advise or point me to the thread
Cheers
Chris


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## John S (5 Aug 2014)

There's one here Chris.

http://ukaps.org/forum/threads/problem-with-resonance-tone-in-diy-spray-bar.30453/#post-320579

I abandoned my acrylic bar as I couldn't stop the noise


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## Vinkenoog1977 (5 Aug 2014)

You should file down the inside of the tube; by drilling, you leave some residue on the inside of the plastic/ acrylic (the heat from the drilling causes the material to melt, and get "glued" to the outer edges of the drilled hole). Easiest way is to find something that is slightly thinner than the inner diameter of the tube, and use double sided tape to stick some sandpaper (180 grid should do the trick) on there, stick it in there, and twist and move it about a bit. Then drill the holes again, because a little bit residue will now be stuck in there, shake the loose bits out, and repeat the sandpaper trick. Should remove all resonance and whistling.

NB: DO NOT DO THIS WITH ACRYLIC! Only with (non-clear) plastic, or you'll ruin the whole see-through look.


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## Andy Thurston (5 Aug 2014)

Just use a brand new drill bit, with a fast drill speed and very light feed pressure. If plastic gets hot while drilling your drill is blunt/cheap and/or your being too heavy handed


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## freelanderuk (5 Aug 2014)

Thanks for replays, I used a new drill in a drill stand at a slow speed, its not clear its PVC so will sand the inside of the tube in the morning, fingers crossed


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## foxfish (5 Aug 2014)

This type of stepped drill is great for drilling clean holes http://www.ebay.co.uk/itm/New-3-PCS...Home_Garden_PowerTools_SM&hash=item2ed4537259


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## freelanderuk (5 Aug 2014)

cheers


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## freelanderuk (6 Aug 2014)

Thanks for all the tips,

I was up early this morning and in the quiet you could really hear it whistling, so off with the spray bars and de burred the insides and reamed the holes with a round needle file , no joy just as bad, drilled out to 3mm, no joy still playing tunes, drilled to 3.2mm de burred and reamed with the round file and silence is golden , just got to cure the fridge and freezer buzzing now

for info the spray bars are made of 20mm grey pvc pipe with end cap glued on and a straight socket glued on connected to the eheim installation sets, length is 26.5 inch with 23 x 3.2mm holes and 2 x eheim 2080 filters so plenty of flow and velocity

thanks
chris


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## ian_m (6 Aug 2014)

Space the holes at slightly different distances and/or wrap elastic bands around the spray bar at varying length along. Put a rubber section in.

If you are feeding two pumps into one spray bar you will have issues, singing/vibrating/resonating is one of them, as between them they pulsate. Also if one pumps fails/wears you will end up emptying the dirty contents of one filter into your tank, which is why it is generally not done. If you are using two pumps, you must have two separate unconnected outlets. This is normally done by each pump feeding only half the spray bar.


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## freelanderuk (6 Aug 2014)

i have a  separate spray bar connected to each filter , they are as quiet as church mice now


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