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Old 10/03/2008, 11:53 AM   #1
miwoodar
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DIY Swirler Stein

I revamped my swirler stein. The originals ran for ~30 months without incident (other than dropping one in the water for a ~1/2 hour...and it lived to tell the tale). I love these things. Great random flow. Easy to build - especially the original version. Cheap - $30 each.

Rather than bump the original thread, I've decided to start a new one. Most of the photos are dead in the original thread. Not seeing the photos made it hard to follow and for this reason a new thread made more sense to me. Here is the original if you have never seen it (http://www.reefcentral.com/forums/sh...5&pagenumber=9).



-------------------------------------------------------------------

HMott built a great version in the original thread. I used his parts list to build my first two. Here is a slightly amended parts list for HMott's version:

$8.50 Housing (Lowes 4x4x2) box

$3.99+S Motor
https://www.surpluscenter.com/item....atname=electric

$0.00 Acrylic arms (I had it laying around any plastic would work these are not big pieces)
1 motor mount
1 motor to tie-rod arm
1 down tube cam

$4.00 rc car tie-rod - ( also posted a link for 4 for $6.69) but I paid $4.00 local to replace the one I took from my rc car.
http://www2.towerhobbies.com/cgi-bi...p?&I=LXJK15&P=X

$5.99 14g wire (lowes) (I got this so it would fit my gromets)

$1.99 1/4" gromets

$0.00 3/4" pvc.. I used about 3 inches of this and for the down tube holder, I had to dremel it out a little, A 3/4" slip coupling would work also.

$0.00 1/2" pvc.. this is the down tube.

ADDED:
Forgot I also bought little bolts, I got one package at lowes for about $2.00 and will have lots extra so it probably doesn't even count.

TOOLS:
Razor knife (x-acto)
Dremel
superglue

Heck I think thats it.. so it comes out to $28.46 plus some for the shipping...

---------------------------------------------------------

Here's an example picture and a video of what that gets you after a couple hours of creative dremeling/supergluing...






-------------------------------------------------------------

Another Option:

I just built a new one for my new tank. This time I used a 3/4" sealed lawnmower bearing to mount the downtube. This was a little harder to do than the original version because I had to trim the outer diameter of the PVC downtube so it would slip through the bearing's inner diameter. I used a table saw for this (not in a safe way!). Being that the original versions lasted for ~30 months and were still going strong, the bearing version is not required but something I was interested in trying. It worked out well so I thought I would go ahead and post it.

Two lawnmower bearings on e-bay will run you ~$10 shipped.



--------------------------------------------------------------

Motors:

The original motor supplier:
The original supplier, www.surpluscenter.com, is still around but does not always keep them in stock. They will be in the reversible AC gear motors section if they are. Here's a link to that (http://www.surpluscenter.com/sort.as...c&keyword=GIAD).

Alternate option for motors:
Go to e-bay and search for "turntable motor". Many options come up. You're looking for a 120 volt version that runs 2 to 3 RPM. This option is a little more expensive than surplus center but still worth the cost. Buying through this option will add ~$15 to the project.

------------------------------------------------------------------

Mounting:

One of the biggest problems with the swirler stein has always been mounting. You'll need to use some creative thinking here. On my last tank I was able to screw the tab on the side of the project box directly into the edge of my canopy. My current canopy did not afford that option. Instead, I dropped the downtube through one of the cord holes in the eurobracing and used velcro sticky pads to secure the box. I first believed this to be a semi-ghetto option but I've since realized how convenient it is due to the inherent adjustability that comes with it - the box can just be picked up and twisted a touch if I want to change the direction of the flow.

In short, we've all seen a bazillion ways to mount things on the rims of our tanks - if you apply a little creativity, you'll find a way to mount a swirler stein.

------------------------------------------------


HTH to anyone who might have interest in building one of these. It's something that has done a lot to improve the flow patterns in my tank and well worth the effort IMO if you're looking for a fun DIY project.


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Last edited by miwoodar; 10/03/2008 at 12:20 PM.
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Old 10/03/2008, 02:08 PM   #2
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Nice!!

I like the new one Mike, may have to try this down the road when I'm "looking" for another DIY project to do.

Thanks for sharing, and all of the descriptive information.

Spleify


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Old 10/03/2008, 04:55 PM   #3
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another motor that would work for the rpm would be microwave motor. you know the one that turns the glass on the bottom those are cheep i do beleave. i ripped an old moro apart to use the motor on my slow mix kaulk reactor


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Great stuff====$5 a can
24-48 hour cure
Epoxy to cover it====little as $5 for small projects or up to $100+ for larger projects
and another 24-48 hour cure
I hope you covered it well cuz if you didnt it will start to break down in a few months
sand is another added cost to cover up the yellow.

Pond foams====$9-$15 a can
24-48 hour cure
DONE! You can cover it with sand if you want to (YOU DONT HAVE TO) though but thats added cost again

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Old 10/03/2008, 04:58 PM   #4
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Right on customcolor. Good idea. I think that's what my current motor actually is...either that or a rotisserie motor from a BBQ. Seems like they are of the same guild. If you search for 'rotisserie motor', e-bay and google searches usually only spit back motors that have neat plastic cases with brand names on the side - tripling the price. I just searched for 'microwave motor' and plenty of good, cheap options came up right away.

Leif - you can't fool me! I've seen your build thread and your tank...you're always looking for the next DIY project.


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Last edited by miwoodar; 10/03/2008 at 05:03 PM.
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Old 10/04/2008, 02:35 AM   #5
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Mike can you get me more info on the sealed bearings? I'm thinking of redoing mine with 2 down tubes run by a single motor in an acrylic enclosure.

Thanks.


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Old 10/04/2008, 09:20 AM   #6
miwoodar
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The double swirler stein - neat idea.

The ebay seller I got mine from is racergirlsrock. They have a $2.99 buy it now for a pair of bearings on auction number 250302074252. I searched for 'sealed lawnmower bearing 3/4' and included the auction description checkbox to find them.


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Old 10/04/2008, 04:14 PM   #7
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i cant grasp how the downtube attaches to the box. how does it rotate and stay dry? i understand that it doesnt get "wet" but you know how it goes.
I just happen to have a few bucks and no homework this weekend so this looks like a great waste of time!


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Old 10/04/2008, 04:31 PM   #8
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In the one made from the project box...

The 1/2" PVC extends into the box by about an inch. The downtube is gray - you can see it in the pic.

The bushing below the box:
The PVC threads through a 1/2" PVC coupler just below the box to act as the lower bushing. I made this by slightly dremeling out the coupler so it would slip entirely over the down tube.

The bushing inside the box:
The 1/2" PVC downtube is capped by a 1/2" to 3/4" adapter. This acts as the upper bushing. The swing arm was made to slip all the way over the 3/4" adapter and glued in place with super glue.

HTH!

I have one I can take apart for photos but I won't be able to get to it today.


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Old 10/04/2008, 05:45 PM   #9
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am i understanding it right in that there isnt a "seal", just basically the box somewhat loosely sandwiched between 2 fittings? for some reason my mind just isnt grasping it yet.


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Old 10/04/2008, 05:48 PM   #10
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I am about to build a couple of these. I am glad you started the new thread. The other is difficult to follow with out the pics.
I ordered two of these motors.
http://www.herbach.com/Merchant2/mer...egory_Code=MTR


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Old 10/04/2008, 06:36 PM   #11
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Is this the correct motors? Its the only one I could find on the surplus site for $3.99?
Its the 8th one from the top: "30 RPM 220 VAC MOLON GEARMOTOR 50 HZ Item# 5-1090"

If not, about how many RPM is a good target to shoot for?


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Old 10/04/2008, 09:05 PM   #12
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Quote:
Originally posted by SWINGRRRR
Is this the correct motors? Its the only one I could find on the surplus site for $3.99?
Its the 8th one from the top: "30 RPM 220 VAC MOLON GEARMOTOR 50 HZ Item# 5-1090"

If not, about how many RPM is a good target to shoot for?
No, the link dngspot posted is what you're looking for. The one you found is 220volt and 30 [email protected] that one looks like its meant for overseas.

Ideally your looking for 1-3 rpm's, the one I used is from a BBQ rotissiery and is rated for something like .78rpm


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Old 10/04/2008, 11:36 PM   #13
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Thanking The Good Lord for a New thread on the "Stein" as I was very disappointed on the pics and links on the old thread.


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Old 10/05/2008, 12:27 AM   #14
miwoodar
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Quote:
Originally posted by kinghokus420
am i understanding it right in that there isnt a "seal", just basically the box somewhat loosely sandwiched between 2 fittings? for some reason my mind just isnt grasping it yet.
You're one the money - the coupler on the bottom and the adapter on the top simply sandwich the box. It's tight enough that it does not shift as the unit is turning but loose enough to keep friction down. The hole in the bottom of the box is just large enough for the pipe to go through.

dngspot - the motor you linked should work great as long as you can fit everything in the box. If you can find a lower profile version it would be easier to work with. I attached a photo of the ones I used below. I found it by searching for 'turntable motor microwave' on e-bay...it's selling for $20 right now but they are often available for $10. This one is auction number 170264457679. The seller's name is Tway.




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Old 10/05/2008, 12:42 AM   #15
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Here's another...auction number 220288843669. Sellers name is esther6lee1250. $9.99 plus $19 shipping. If you can get the seller to do combined shipping and split it with a pal or two, it would be cheaper than the last option.




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Old 10/05/2008, 01:33 AM   #16
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Quote:
Originally posted by cdentii1
Thanking The Good Lord for a New thread on the "Stein" as I was very disappointed on the pics and links on the old thread.
Yeah, that old thread became a boneyard. Any particular pics you want to see again? I have most of them but the OP's on my C:drive. Here's some of Hmott's pics...

Here's a point of departure between Hmott's version and mine. I dremeled out a coupler until it would slip onto the downtube and glued it so it makes light contact with the bottom of the box. You can also see that he ran his electricity in once and split it from there to the MJ and the motor. I ran in wires for both the MJ and the motor separately. I guess I felt a little lazy that day and didn't want to figure out how to run everything from one input wire.


Slick mounting method. He glued a tab to the bottom side of the box and I *think* he inserted screws into the down-turned tabs to lock the box to the rim of his tank.


I mounted my original MJ mods like HMott did. It's actually quite easy to cut the end of the pipe to just slide into the MJ. A drop of superglue and done. I went a different route with my current swirler stein. I trimmed down the suction cup bracket to about and inch long - down to just about half of the piece that actually slides into the MJ. I then glued that to the end of my PVC downtube. This allows me to detach the MJ any time I want so I can slip the assembly out of the hole it's mounted through in my eurobracing.


My build has a few points of departure from what is shown in this pic. I didn't glue the coupler to the box the way Hmott did (I was concerned about binding). Rather, the piece inside the box turns with the downtube. Also, I didn't use any of the acrylic braces he did. Either way. I think the way I did it is a little easier and it worked for 30 months without any problems (and would still be running if I didn't tear down the tank and rebuild them).



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Last edited by miwoodar; 10/05/2008 at 01:46 AM.
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Old 10/05/2008, 08:00 AM   #17
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Quote:

dngspot - the motor you linked should work great as long as you can fit everything in the box. If you can find a lower profile version it would be easier to work with. I attached a photo of the ones I used below. I found it by searching for 'turntable motor microwave' on e-bay...it's selling for $20 right now but they are often available for $10. This one is auction number 170264457679. The seller's name is Tway.

I bought these on EBay.
http://cgi.ebay.com/ws/eBayISAPI.dll...ayphotohosting

They look to be the same model you are using and should fit in the low profile boxes that I have seen at HD.

I will call the folks that I ordered the first set of motors from on Monday and cancel the order. If there is a problem then I will use them for another project.


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Old 10/05/2008, 09:37 AM   #18
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Quote:
Originally posted by miwoodar
[B]You're one the money - the coupler on the bottom and the adapter on the top simply sandwich the box. It's tight enough that it does not shift as the unit is turning but loose enough to keep friction down. The hole in the bottom of the box is just large enough for the pipe to go through.
Thanks, i got a grasp now! im off n the hunt for a microwave motor now. salvation army here i come!!


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Old 10/05/2008, 10:16 AM   #19
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Quote:
Originally posted by dngspot
I bought these on EBay.
http://cgi.ebay.com/ws/eBayISAPI.dll...ayphotohosting

They look to be the same model you are using and should fit in the low profile boxes that I have seen at HD.

I will call the folks that I ordered the first set of motors from on Monday and cancel the order. If there is a problem then I will use them for another project.
Looks like an excellent choice dngspot. $10 motor and $6 shipping - pretty good.

Here are the specs on that motor for reference after the e-bay link dies...

Genuine Frigidaire part Number: 5304448488
Motor Markings:
* ST-16 (don't actually need this but posted it JIC)
* KX63MSAPS (don't actually need this but posted it JIC)
* 60 hz
* 3 RPM
* 120 Volts

Seller: supplystuf
Auction number: 380069508342


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Old 10/05/2008, 10:39 AM   #20
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Mike, Thanks for re-posting all of this very valuable info.

Do you think that these motors that you guys have been linking are strong enough to turn a larger powerhead such as one of the Tunze 6101 streams?


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Old 10/05/2008, 10:42 AM   #21
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I'm glad people are finding this information useful. I bumped the old thread a few times in the past couple of years but it never caught traction again.

Without a doubt. These motors have *plenty* of untapped potential.


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Old 10/05/2008, 11:04 AM   #22
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Quote:
Originally posted by miwoodar
I'm glad people are finding this information useful. I bumped the old thread a few times in the past couple of years but it never caught traction again.

Without a doubt. These motors have *plenty* of untapped potential.
Thats VERY good news. As a DIY addict... this is a very appealing project for me!

Is it a feature of the motor or of the motor-shaft connection that alternates the direction of the Powerhead back and forth between a 180° range?


EDIT: Just bought the same model motor that dngspot posted. $16 to my front door isnt bad!.


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Old 10/05/2008, 11:10 AM   #23
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It's the motor-shaft connection. Here's a video of the assembly in action. Never mind the noise - it's virtually silent - I think my camera turns up the microphone when you're trying to be quiet.

***edit: You can play with the length of the arms to get more or less rotation. Mine are ~90 degrees. I think someone posted in the original thread stating that if you go over ~135 degrees binding will become a problem. ***




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Old 10/05/2008, 11:15 AM   #24
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Thanks for this video Mike! Im going to be making one that will allow my Stream to sit in the center of my tank along the back and cycle a full 180°, allowing it to basically sweep across the entire reef. This, along with a controller ramping the output up/down will make for some totally random flow. The SPS will love it!


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Old 10/05/2008, 12:27 PM   #25
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I am going to make two of these things to move AC70 streem mods. Those guys put out 3000 gph. I have been using them on a magnet bace but, like the idea of them moving. Being able to remove the cords from view will be nice too.
They will also allow me to use the stock mounting hardware so there will be no mod to the actual housing.


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