The "Hitchhiker's Guide" to the Maxi-Stream mod

[JohnL]

This thread was automatically split due to performance issues. You can find the rest of the thread here: http://archive.reefcentral.com/forum...26#post7169326

[dhnguyen]

Originally posted by brians_224
RE: Ball's Shroud

Is there a limit to how short the shroud can be? (As long as it covers the prop )

I have the lutz mods - I've become disenchanted with their performance and size.

The shorter the wider and more dispursed the flow, the longer, the more focused and concentrated. This is why I make mine shorter.

[Snarkys]

lol how many times has this been split ?

[dhnguyen]

Well for those who are just discovering these threads about the mods

OK here goes the parts list again with where to get them


The shroud:

-Schedule 80 1.5" PVC pipe (dark gray if you order from mcmaster.com part# 48855K25) for the 1.25" up to 1.4" propellers - Home Depot, Lowes, McMaster.com

-1.5" slip coupling for the larger 1.75" Dumas propeller

The propellers:

-1.38" Octura 2035 or 1435

-1.57" Octura 1440 or 1240

Octura props can be ordered from http://www.funrcboats.com/category.aspx?categoryID=109 or directly from Octura (they have no website nor email)

Octura Models Inc
(847) 674-7351
7351 Hamlin Ave
Skokie, IL 60076

-1.75" Dumas - Towerhobbies.com (http://www2.towerhobbies.com/cgi-bi...p?&I=LXE472&P=0 or http://www2.towerhobbies.com/cgi-bi...p?&I=LXE473&P=0)

Everything else:

-0.098" carbon fiber rod - Towerhobbies.com (http://www2.towerhobbies.com/cgi-bi...p?&I=LXJDP4&P=M) or your local hobby shop
-3/32" 316 stainless steel welding rod - welding supply shop, mcmaster.com

-3.16" thin walled rigid airline tubing.- LFS, Petco, Petsmart, DrFostersmith.com (http://www.drsfostersmith.com/produ...&pc=1&N=0&Nty=1)

-Flexible airline tubing 3/16" ID - LFS, Petco, Petsmart, DrFostersmith.com (http://www.drsfostersmith.com/Produ...4&N=2004+113403)

-CA or super glue - Towerhobbies.com. local hobby shop, Home Depot, Lowes, Target, Walmart, etc...


Cross brace: Can be made out of 1/4" thick scrap acrylic, 1/4" acrylic bars, or rigid airline


The pump:

Maxijet or Aqua Clear or whatever else you have on hand.

[Snarkys]

lol good call : )

[parvo99]

How does RC feel about people selling this stuff on the forums? I posted before about having extra parts, and now I also have a bunch of shrouds, because all I could find was 10ft of schedule 80 1.5 inch conduit. I'm not trying to sell it commercially, but wouldn't mind selling the extra supplies I have to those who don't want to buy excessive amounts of parts, or those who just don't want to have to make a shroud. Is this acceptable? Please delete this post if it's not.

[dhnguyen]

parvo99- I'd do it offline if I were you

RC has very strict rules about selling on here.

D.

[hyperfocal]

Wow pricey little pump.

Curious where did you find that out from?

I emailed Alita directly. Here's the meat of their reply:

The DCP11 DC water pump is $50 each and immediately available. If you like to order the pump, please feel free to give us a call at 626.962.2116 9am to 5pm Pacific Time.

The pump is amphibious, the connection between the pump and the 2 electrical wires is sealed by epoxy. You can apply more insulation for protection against damage. For power cord manufactured with protective PVC jacket, minimum order of 1,000 units required.

I'm a little concerned about their description of the insulation on the electrical connection.. it doesn't sound robust. While the health risks are a lot lower here (low DC voltage vs line level AC), I still don't want my pump shorting out and failing. Murphy's Law and all that.

Anyways, at $50 a pop they're too rich for my blood.

[ChemE]

Originally posted by Snarkys
lol how many times has this been split ?

This was the second split. I think its working on being one of the longest threads on RC.

[GSerg2]

Ball, is there anything that ensures it will start the proper direction?

Very nice looking btw.

Thanks

[Ball]

Originally posted by GSerg2
Ball, is there anything that ensures it will start the proper direction?

Very nice looking btw.

Thanks

I still need to add a stopper to the design to ensure it starts in the same direction everytime.

[Brent Thomann]

Originally posted by ChemE
This was the second split. I think its working on being one of the longest threads on RC.

I think someone should start another thread for doing this mod with different pumps other then the MJ's so this thread can get back on track, ya say?

[dhnguyen]

Well I don't think it's off track per se using an Aqua Clear or other pumps instead of a Maxijet. Still the same mod just different pumps is all.

[Brent Thomann]

Originally posted by dhnguyen
Well I don't think it's off track per se using an Aqua Clear or other pumps instead of a Maxijet. Still the same mod just different pumps is all.

Its confusing for the new people coming on. Subject says Maxi-Stream mod not Aqua Clear or other pumps mod.

reason I brought this up, as its been mentioned recently, my cousin just bought some MJ900's for this mod and I sent him your link for the thread and he said its very long and confusing, latest post don't even talk about the MJ. I'm sure I'm not the only one that agrees.

D' I think you just want to hold the title for the longest thread which I'm sure you already got.

[hmott]

I also think it would be nice to pull it out.. I follow this thread better then most I'm sure, I'm subscribed to it anyway. And I'm not even certain what the deal is with the ac's. I did go ahead and purchase one, but I hate to think about the number of pages I'll need to go through to find the info I need to mod it. The MJ was easy, But I'm very uncertain about the stopper on the ac's.

Maybe it should just split off fixed shaft versus rotating shaft mods. Thats really the big difference anyway.

[dippin61]

its so weird seeing a thread split without seanT as the poster

back on track.

yeh, ive also found the shorter the shroud, the better "even" dispersment of flow. amazingly its quite different with a short shroud vs. long one.

my longer shroud would tend to come out on one side of the output more then the other. if that makes sense. shorter shroud fixed this.

and also, dunno if this makes any difference, but i had to use a 2040 octura prop at the time, cuz thats all i could get locally, until recently. anyways, since its a 40mm prop, it wouldnt fit inside the 1.5" pvc i had. so i had to "bell" it out a bit, as someone said earlier in the thread. so there is some very nice clearance between the pvc and prop. more so then with a 1435 on stock 1.5" pvc.

i can tell you, my 55g with sand, cannot handle the flow of this power head without blowing the sand everywhere.

[Ball]

I think its ok to have both pump mods in this thread. I would have never heard about the Aquclears otherwise. Plus, most of the same design and theroy can be used for both. I moded many maxijets because of this thread. Now, I moded an aquaclear because of this thread. If another pump comes up that seems even better in this thread, I may mod that. Its a lot of info, but its good info. Keep it coming!

[hmott]

Now that talk has moved less on how to do it, and more on increasing effeciency. I have a question. Anyone know how close the prop should be to the sides of the housing? Its my understand, at least with air lift, the closer the tolerance the better. Yet I have, and many others I believe, a prop in my housing with probably 1/4" or more area around it. Wouldn't we get much better perforance using a housing that is just barely, close the better, larger than the prop?

I've been too busy with other DIY projects to try making several housings for it to test, but I'm pretty sure thats the case. I just didn't think about it until I had already made mine. Maybe when my aquaclears arive I'll test with them.

[Ball]

I have found that I get more flow with more space from the tip of the prop to the edge of the housing.

[hmott]

Ball, I understand that. I mean from the edge of the propeller to the edge of the housing on the inside.

[Ball]

The closer the prop diameter is to the housing diameter = less flow from the prop. At least in all my testing. As the space gets tighter, it seemd to chike the prop output. Im thinking thats what you are agreeing with.

The closer the end of the prop is to the end of the housing equals a wider smoother flow. This may feel like more flow. Are you finding the same thing?

[dhnguyen]

Originally posted by humpn247
Its confusing for the new people coming on. Subject says Maxi-Stream mod not Aqua Clear or other pumps mod.

reason I brought this up, as its been mentioned recently, my cousin just bought some MJ900's for this mod and I sent him your link for the thread and he said its very long and confusing, latest post don't even talk about the MJ. I'm sure I'm not the only one that agrees.

D' I think you just want to hold the title for the longest thread which I'm sure you already got.

Ok that said. Who's stepping up to do the new thread?

[dhnguyen]

Originally posted by Ball
The closer the prop diameter is to the housing diameter = less flow from the prop. At least in all my testing. As the space gets tighter, it seemd to chike the prop output. Im thinking thats what you are agreeing with.

The closer the end of the prop is to the end of the housing equals a wider smoother flow. This may feel like more flow. Are you finding the same thing?

I have noticed the same as well. I think the principles in air flow may not work the same in water. But it's still interesting to find out though.

[Aquaduck]

I'm thinking of a way to keep these pumps running all the time and just switch the voltage going to them up and down like the new SEIO controller. I made a controller eons ago that did this for the original Quiet one pumps (the ugly beige and red ones). I had them alternating the direction of water returning from the sump to my tank on each end and I had to keep them running otherwise they would back-siphon when stopped. It was a simple circuit and used triacs and a step down transformer for the "low" voltage. The device switched from full 120VAC to something around 56VAC which was just enough to keep the pumps running. All I need to do is find out at what voltage the Maxi-jet stalls at. I've got to go and look for my DVM and variac and do some more thinking....

[wsc]

Aquaduck thats a cool idea. Ive read that (ideally) you should change the frequency in proportion to the voltage applied to the motor. ie at 56vac you should be running around 30hz or so.

I wonder how hard it would be to make a true variable frequency drive.. hmm. Probably pretty hard if seio is having such a hard time with it.