Dart threadwheel skimmer build

[zapata41]

dont erally get that last post. i am not building a new skimmer, just thinking about possibly changing pumps but think i am gonna just keep mine as it is.

now i just need to know where to get the oring material from for a different project

Tim

 

[ChemE]

<a href=showthread.php?s=&postid=8391993#post8391993 target=_blank>Originally posted</a> by jnarowe
...Can you reply with your equations to arrive at that? I am confused by a couple posts and how that is determined...

Me post equations? Perish the thought!

 

[mavgi]

<a href=showthread.php?s=&postid=8392044#post8392044 target=_blank>Originally posted</a> by zapata41
dont erally get that last post. i am not building a new skimmer, just thinking about possibly changing pumps but think i am gonna just keep mine as it is.

now i just need to know where to get the oring material from for a different project

Tim

sorry i thought you going to build new one

 

[john f]

OK MIke,
I swapped out my needlewheel for the same design threadwheel you are using.....mesh on front and back, with some large holes drilled into the impellar.
The results are again.......almost identical to the needlewheel.
I am running at 155-160 watts and the bubble size and turbulence in the neck look pretty much the same.
Any more air into the pump than 155 watts and it burps.

So....not the shoot down the whole threadwheel thing, but I think your volute changes and perhaps venturi input are making the most difference>

BTW, I cleaned out my PM box.......sorry about that.
Could you please resend your earlier PM?
I really want to learn more about which material you relieved from the volute especially.

John

 

[zapata41]

no prob, still need to confirm the oring sources though.

 

[jnarowe]

<a href=showthread.php?s=&postid=8392049#post8392049 target=_blank>Originally posted</a> by ChemE
Me post equations? Perish the thought!

Sweet! Thanks. I love your sig. I have been embarrassed at myself for considering to buy a commercially produced kalk stirrer but I really need to get one now and don't have the time to build one until late December. Can you point me to a pic of your skimmer? Have I already seen it? You can see mine by clickig on the red house. I think you will like it. What stones are you using?

 

[ChemE]

<a href=showthread.php?s=&postid=8392297#post8392297 target=_blank>Originally posted</a> by jnarowe
Sweet! Thanks. I love your sig. I have been embarrassed at myself for considering to buy a commercially produced kalk stirrer but I really need to get one now and don't have the time to build one until late December. Can you point me to a pic of your skimmer? Have I already seen it? You can see mine by clickig on the red house. I think you will like it. What stones are you using?

I followed your setup thread; that thing is/was a beast. Mine was an uber cheap Home Depot job; few feet of 4" PVC, 4" to 2" PVC reducer, 2" PVC neck, yada yada yada. Powered by a Whisper 60 running 6 Lee's limewood airstones. Whole thing ran me about $60 (most of that was the pump and airstones) but it did pull about 4 oz/day of espresso out of a lightly stocked 55. Best part was at that back pressure the Whisper 60 only consumed 2 watts! (Kill-A-Watt).

I've since been experimenting with the dark side and bought an Octopus NW-200 which ran stock all of 2 minutes before I yanked off the venturi and modded it. All this talk of thread wheels has visions of an Eheim 1250 spinning some DLS dancing through my head though...

 

[hahnmeister]

According to my old thermaldynamics text book's conversion tables...lol...Im goin' oldschool...

1 cubic meter = 1000 liters = 35.315 cubic feet. So for every 1000lpm, its about 35 cubic feet... divided by the time. That might help some conversions. I just set up ratios all the time.

 

[jnarowe]

hmmmm...I have heard from some local guys that the gutter guard wheels are better than the threaded wheels, but I don't have any personal experience with them. I can't wait to get the Aquatic-Eco air stones...you guys have me chomping at the bit to improve my skimmer!

Once I have installed them and have some data to go on, I will go back to my Sequence 4300 DIY needle wheel project so I can compare the two in person.

 

[ChemE]

Google's calculator is all grown up and has some basic science under its belt. Just punch in what you want in the search textbox and viola!

 

[smjtkj]

<a href=showthread.php?s=&postid=8391936#post8391936 target=_blank>Originally posted</a> by zapata41
looking around at orings and on mcmaster i only find silicone with a durometer shore of 70 which is pretty hard . also are you ordering them on the roll and cutting and superglueing them to size or ordering them premade

Thanks

Tim

I am ordering them premade from there. I have gotten 3 so for and had no problems.

 

[smjtkj]

<a href=showthread.php?s=&postid=8392563#post8392563 target=_blank>Originally posted</a> by jnarowe
hmmmm...I have heard from some local guys that the gutter guard wheels are better than the threaded wheels, but I don't have any personal experience with them. I can't wait to get the Aquatic-Eco air stones...you guys have me chomping at the bit to improve my skimmer!

Once I have installed them and have some data to go on, I will go back to my Sequence 4300 DIY needle wheel project so I can compare the two in person.

Take it for what its worth, but the mesh wheel produces smaller bubbles.

 

[hahnmeister]

I dont think the impeller/needlewheel makes that big of a difference at all for bubble size. Most of the mixing in the pump is done as the water and air mix spins around the outer parimeter of the impeller shroud before it exits. The type of needlewheel, meshwheel, etc is just there to prevent any large pockets of air from decreasing the performance of the pump... many smaller pins make more smaller blades to help with flow. The type of needlewheel may vary the throughput capacities more, but I dont think it does much for bubble size. Much of the air and water going through a pump never even touches the needlewheel... it enters the shroud and passes right over it on its way to the outer ring due to centrigugal force.

 

[smjtkj]

<a href=showthread.php?s=&postid=8392111#post8392111 target=_blank>Originally posted</a> by john f
OK MIke,
I swapped out my needlewheel for the same design threadwheel you are using.....mesh on front and back, with some large holes drilled into the impellar.
The results are again.......almost identical to the needlewheel.
I am running at 155-160 watts and the bubble size and turbulence in the neck look pretty much the same.
Any more air into the pump than 155 watts and it burps.

So....not the shoot down the whole threadwheel thing, but I think your volute changes and perhaps venturi input are making the most difference>

BTW, I cleaned out my PM box.......sorry about that.
Could you please resend your earlier PM?
I really want to learn more about which material you relieved from the volute especially.

John

John, I was mentioning that I took out as much material as possible out of the whole cover. What is the height of the reaction chamber on your skimmer? The height may be a factor too. The reaction chamber is only 24 inches tall on my skimmer. If I run the pump wide open with no restriction of the valve, it runs 150 watts. I only turned the valve a little bit and watched the air meter to get the best air draw. The adjustable vevturi is a 3/4 inch barb fitting cut at an angle. Nothing special about it.

 

[jnarowe]

<a href=showthread.php?s=&postid=8392686#post8392686 target=_blank>Originally posted</a> by hahnmeister
I dont think the impeller/needlewheel makes that big of a difference at all for bubble size. Most of the mixing in the pump is done as the water and air mix spins around the outer parimeter of the impeller shroud before it exits. The type of needlewheel, meshwheel, etc is just there to prevent any large pockets of air from decreasing the performance of the pump... many smaller pins make more smaller blades to help with flow. The type of needlewheel may vary the throughput capacities more, but I dont think it does much for bubble size. Much of the air and water going through a pump never even touches the needlewheel... it enters the shroud and passes right over it on its way to the outer ring due to centrigugal force.

So don't you think this would work just as well?

 

[spazz]

or if you want to go the other direction its 28.316846592 liters to the cubic foot. he he he he he

 

[smjtkj]

<a href=showthread.php?s=&postid=8392038#post8392038 target=_blank>Originally posted</a> by mavgi
look nice mike can you show your air pipe because i think you can make the bubble more small without to increase to much the watt

I will take another pic of the neck when I get home. The bubbles in the neck are usually smaller than that. I had just lowered the level with the outlet pipe and it was trying to readjust itself and build another foam head. I wanted to get a little drier skimmate.

 

[john f]

It's not the height of the reaction chamber..........It draws about the same wattage as I am filling up the skimmer.

Somehow your pump is able to accept more air without cavitating or burping.
Did you remove material from the FRONT cover only? Did you remove from the SIDE of the cover or the FACE, or both.
On my volute face there is an indented area that goes all the way around the front input. It looks like yours was gone. COrrect?
Your venturi setup sounds just like mine so that may not the the difference.


John

 

[Beenalongtime79]

<a href=showthread.php?s=&postid=8392686#post8392686 target=_blank>Originally posted</a> by hahnmeister
I dont think the impeller/needlewheel makes that big of a difference at all for bubble size. Most of the mixing in the pump is done as the water and air mix spins around the outer parimeter of the impeller shroud before it exits. The type of needlewheel, meshwheel, etc is just there to prevent any large pockets of air from decreasing the performance of the pump... many smaller pins make more smaller blades to help with flow. The type of needlewheel may vary the throughput capacities more, but I dont think it does much for bubble size. Much of the air and water going through a pump never even touches the needlewheel... it enters the shroud and passes right over it on its way to the outer ring due to centrigugal force.

I know you've made your observations on this, but I disagree... there is a reason that manufacturers moved toward using needlewheels/pinwheels/ and now threadwheels to build a better skimmer pump.

There is no way that a normal impeller can create the same type of bubbles as those other modalities I mentioned earlier. If this were so, the companies would have just kept using the stock impellers and modified other aspects of the skimmer pump.

Peace,
John

 

[smjtkj]

<a href=showthread.php?s=&postid=8392800#post8392800 target=_blank>Originally posted</a> by john f
It's not the height of the reaction chamber..........It draws about the same wattage as I am filling up the skimmer.

Somehow your pump is able to accept more air without cavitating or burping.
Did you remove material from the FRONT cover only? Did you remove from the SIDE of the cover or the FACE, or both.
On my volute face there is an indented area that goes all the way around the front input. It looks like yours was gone. COrrect?
Your venturi setup sounds just like mine so that may not the the difference.


John

That is correct. I took material out all the way around. The material all the way around the intake is now smooth. There is to raise or fall in the face.