my diy needle wheel dart pump

[jnarowe]

You guys are making me dizzy. I just "fixed" my collection cup cap so that air can't excape and that created too much back pressure and forced the bubble head down to the point that the skimmer wasn't removing foam. I have got to stop "fixing" stuff!

I guess the answer would be to make a larger than 3/4" drain line to the bucket but I am also considering something else:

Maybe installing a carbon filter directly to the side of the collection cup would work better? Like a 2" BH and PVC canister? WHat do you guys think?

 

[spazz]

that might work. but it might be too heavy for your cup to hold it up.

 

[jnarowe]

I don't think weight is a problem, I just don't want to push foam through the carbon filter. Then I would have accomplished nothing.

 

[Roland Jacques]

Bill, i cant tell if that lower box is 1/2" or 3/4". maybe spazz has a thought about the weight on it. from what i can see it looks well supported except maybe very the center. under the defuser. .

i dont no if you still have access to your lower section, but if it is 1/2" you may want one more piece of supporting PVC near the very center. id hate to see that defuser brake loose from any bowing over time. what do you think?

 

[jetaero]

I am going to try this.. very cool design.

 

[ChemE]

Make sure the carbon bed has a large enough CSA (cross-sectional area) such that it doesn't create appreciable back pressure. I drilled about 40 0.5" holes just inside the outer edge of the top of my collection cup. This provides plenty of area for the air to escape. You could just put a 1" thick layer of carbon right on top of my collection cup lid and filter 100% of the air it passes while creating virtually no back pressure. I'll post a pic if my description isn't clear.

 

[jnarowe]

That makes a lot of sense but with one question: Doesn't foam push out through the holes?

 

[ChemE]

No, but I've got WAY less air going through my skimmer than you do. But if the foam does push through the holes, then the cup clearly isn't large enough to cope with the air pump. Of course, that's what makes this iterative process so fun.

 

[spazz]

<a href=showthread.php?s=&postid=7158447#post7158447 target=_blank>Originally posted</a> by yourfishman
Bill, i cant tell if that lower box is 1/2" or 3/4". maybe spazz has a thought about the weight on it. from what i can see it looks well supported except maybe very the center. under the defuser. .

i dont no if you still have access to your lower section, but if it is 1/2" you may want one more piece of supporting PVC near the very center. id hate to see that defuser brake loose from any bowing over time. what do you think?

he wont need a support there because the water pressuse will be equal between the top and bottom. that plate only has to hold the weight of the main tube. and if you think about it the pressure will be pushing the other way. it will push out on the box.

 

[jnarowe]

ChemE Well my collection cup is on the small side just this side of UGLY but I had ceiling height issues! It is a good learning experience though in that when I built it I screwed up the cap so it didn't fit right and the skimmer performed incredibly well, and now that I fixed it and cleaned it I am not getting as much foam production.

I wonder if there is a "break-in" period each time I clean the riser? Don't get me wrong, it is working well, just not as well as before. If the skimmate didn't stink so bad, I would go "topless"!:lol:

Maybe I'll add another drain line. That might work too.

 

[ChemE]

Jonathan,

From your description, it sounds like your "fixed" skimmer is forcing your airpump to fight against quite a bit more back pressure and so your not getting as much air into the skimmer as it optimal. I'll be curious to see what happens when you give it a few more vent lines. One drain line should be ample, just take a few vent lines off the collection cup top.

 

[jnarowe]

I pulled off the carbon filter which is about 3-1/2" diameter leaving that size hole in the bucket lid. Once I did that the foam production ramped back up. So there we have it...I need more holes!

 

[Roland Jacques]

<a href=showthread.php?s=&postid=7159180#post7159180 target=_blank>Originally posted</a> by spazz
he wont need a support there because the water pressuse will be equal between the top and bottom. that plate only has to hold the weight of the main tube. and if you think about it the pressure will be pushing the other way. it will push out on the box.

duh, how did i missed that. thanks Spazz

 

[Bill Wann]

Got the top flange done tonoght , that was fun .
Here some pics . The oring is not seated thats why its sticking up so high .

 

[Bill Wann]

The center is not cut all the way out yet

 

[Bill Wann]

On the subject of how stong th ebottom is , dont worry about that going anywhere any time soon . Its all 1/2 all the way around and supported when needed . Its one heavy solid mother . Built like a brick s**t house . More than enough to carry the weigh and then some .

 

[Carman34L]

AAHhh, nothing like a skimmer that has more water volume than my whole system!

 

[got2lb]

by Carman34L
AAHhh, nothing like a skimmer that has more water volume than my whole system!

The skimmer, heck the Cup alone holds more than a LOT of peoples systems! 21 gallons I believe he said! :eek1:

 

[Bill Wann]

The top flage has been sanded and polished and the bolt holes have been countersunk . I gulued it to the main tube and now its drying .
Next I have to router out the excess on the main tube and glue it to th e base . The main body will be done tommarow and the cone should be done on thursday .
with alittle luck it will be running by this weekend .

 

[jnarowe]

Amazing work Bill. Very impressive.