DIY flare nozzle

[Mihai]

Hi,

I'm building a nice return manifold that will have some 20 output when finished. However, I'd like to increase the speed of the water coming out of the exits, so I need to go from 3/4 to something smaller.

The right (and expensive!) thing to do would be to buy 20 flare nozzles:

http://www.marinedepot.com/md_viewItem. ... uct=LL1315

However, that would be about $110 + shipping. I was hoping to get them (much) cheaper than that: I thought that I can take the CPVC and heat it in boiling water and then press it into a nozzle. It turns out that boiling water is not hot enough (and I don't have a heat gun).

What's the next best thing? I don't really mind the shape - round is good, square is good. It just has to fit to a 3/4" CPVC and be cheap .

Please don't give me the lecture about how expensive this hobby is.
I do not skimp on important things (tank, skimmer, LR), but this doeasn't mean that I want to buy everything retail.

Thanks for the help,
Mihai

 

[tangir1]

Heating PVC-based plastic is very dangerous due to the type of chemicals released when overheated/burn. It can also be a fire hazard.

With that said, you can try to heat the plastic under a MH. Believe me, it is hotter than any heat gun you can buy

There are a lot of way to bent thermo plastics, but I am relucent to say any on this board due to the reason above. Sorry.

But if you want to bend acrylic, I am sure a few dozen of people can give you good answers.

 

[liquid]

Why not just take a 3/4" PVC cap and take a table saw and just run a slot thru it?

Shane

 

[tangir1]

The issue is the high back pressure when a cap is used. But I guess Mihai may not mind about his, since he is more concern about velocity then flow rate.

 

[Mihai]

Well, I'm fresh out of MH, but the PVC cap idea ROCKS.

See, I knew that it's good to post on the RDO. I banged my head yesterday for a few hours for a decent solution and the PVC cap is what I was looking for: it's neat, cheap, and lots of options regarding
opening size (posible to change it later), I can even do two-three openings in the cap.

Actually I will try to strike a balance between the velocity and flow rate: I don't want to add too much back presure, while I'm trying to have the "jets" reach the bottom of the tank and clean the rocks/detritus.

Thanks a lot guys, that's great.
Mihai

 

[Anonymous]

I got my heat gun at HD for about $35. Add 15 or so 3/4" fittings,(about $.20 EACH) and you're still WELL under $110. *(and you get a heat gun in the end!)

HOWEVER, do the bending in a WELL VENTALATED area.

B

 

[ryangill]

you can submerge the pvc in boiling water for about 30sec and then squeeze the end with some pliers to make a flare.

 

[Mihai]

Negative. I left it there 10 minutes and still didn't bend. Actually it was CPVC but both on PVC and CPVC the presure rating and temperature are similar.

That's what I hoped that will work, but it doesn't.
M.

 

[tangir1]

Mihai, you need something more that 100C/212F to soften the pipe. If it works, they won't use it on plumbing, would they?

 

[Mihai]

Yup, I know this from experience (although reading on the pipe it or logic should have suffice ). I was just trying to save ryan the trouble of trying the trick himself (and fail miserably )

All the best,
Mihai

 

[Danno]

One way to heat PVC is to use cooking oil. Water has l lower boiling point than oil so it can only get to 212 and then it boils. Oil on the other hand can be heated to over 400. Just make sure there is no water on the pipe. Put about 3-4" of oil in a pan on the stove and heat. Be carefull not to over heat the oil(flame on!) 8O Use tongs to hold the PVC in the cooking oil till it softens then mold with a piece of wood before it hardens. I have used this method for making flairs for the ends of potato gun rockets ( dont ask) and it works fine. Just be carefull the PVC gets extreamly hot. Good luck.

 

[tangir1]

Just curious, do you throw the oil away afterward, save it for future project, or just pour it back into the bottle without telling your wife? 80

 

[Anonymous]

I have used this method for making flairs for the ends of potato gun rockets ( dont ask)

Got any plans?

Had to ask!

B

 

[Mihai]

Thanks for the oil tip, I'll try when the wife is in park with the kids

Regarding the "potatoe gun rockets": these three words in a DIY forum... it's impossible not to ask. Please, please... .

M.

 

[tangir1]

just want everyone to know that you should *never* reuse the oil for human consumption after you do the procedure above. I am sure everyone knows.

In regard to the potatoe gun, maybe those that are interested should PM Danno...

 

[Danno]

Every thing you ever dreamed of is here. Check out the video clips of the Mega launcher. I have a dream!

http://www.spudtech.com/

here it is 8O http://www.spudtech.com/detail.asp?id=26

This is nuts, I so have to try this!

 

[Danno]

Here is the link to the oil proceedure. Please be carefull and kids.....don't try this at home.

 

[Danno]

oops for got hte link:

http://burntlatke.quibble.com/rocket.html

creative minds at work. I'm glad I live in the country so I can play with this stuff and not haveing the Man breathing down my neck. We all need toys.

 

[Mihai]

Cool. Those look like great toys (too good actually ;-) ).

M.

 

[Anonymous]

The spud guns are fun , you could use barb fittings as your velocity nozzles