DIY cone skimmer

[Fishboy93]

I'm thinking about build a DIY version of the ATB cone skimmer to replace the css65 on my 50G reef. I'm planning on build a "nano" of the nano version, which has a 7.5" base and 4" neck. My version will have a:

6.5"-->3" base that is 10" tall
3" neck that is 6" tall

so with collection cup it will be about 17" tall

which I'm afraid would be a little short....

the angle at the top of the cone is 20*

with a 2.5" neck it add about 1.5" making the main cone 11.5" tall

So to all you DIY skimmer masters out there would a 3" 2.5" or 2" neck be best for the skimmer and what length as well.

Thanks in advance,
Kevin

[reefnewbie54321]

how do you plan on building the actual cone

[Fishboy93]

I already did the math for it:

If you take a 37.4" diameter circle and cut out a slice that has an angle of 62.7* and bend it around It will form a 6.5" diameter cone that is 18.4" tall.

I will build a jig out of wood/cardboard that is also this size. Then i will use a heat gun to bend the acrylic because its only 1/8" thick, progressively clamping and bending until it is complete. I know it won't be 100% perfect so i'll probably use a 1" strip on the seam to ensure it holds water.

[reefnewbie54321]

The acrylic is going to craze pretty bad but I am definitly interested. I thought about doing this aswell

[Fishboy93]

ya that is my concern as well if it doesn't look structurally sound I probably won't use it. it seems there's no real way to get around it tho.

but a sheet of 1/8th isnt too expensive i think its worth a try.

[Fishboy93]

anyone have an opinion on the neck size, I'm leaning toward 3"

[Fishboy93]

sketchup teaser built to scale:

http://i90.photobucket.com/albums/k255/kdawg7990/coneskimmer.jpg

[Fishboy93]

bump... this will be my first DIY skimmer so I'm any advice at all is greatly appreciated.

[Fishboy93]

pump wise i'm thinking a mesh modded Quiet One 2200 because i'm afraid the 300 might be a bit too much

[OnlyCrimson]

Are you sure the acrylic can bend like that? I guess if it was really thin it might.

[kingsland]

This site provides instructions on how to make a cone.

http://www.polyfab.biz/plastic_cones_fabricate.htm

[liveforphysics]

I'm extremely interested in having a large acrylic cone built for me. I require one about 3 times that size to be fabricated for me. If you find any good sources to make the cone, please contact me as I am ready to have one built.

Your skimmer design looks great! The properties of a cone migrating bubbles is a much better functioning shape than the typical cylinder with a cone on top.

Best Wishes,
-Luke

[JCTewks]

an AC70 w/ a custom volute would be a good candidate for that skimmer. a 3" neck would be the smallest IMO.

[Fishboy93]

I don't really have the tools to machine a custom volute for the 802, what do you think of the QO 2200. I would probly just run it with stock volute, mesh, and DIY venturi?

[Fishboy93]

or how about a mesh modded gen-x pump? i would need around 300lph of air right?

[Fishboy93]

Thanks kingsland I calculated it all myself then double checked on that website, all seems ok!

OnlyCrimson, I'll be using 1/8" for the body so it shoul bend pretty easily, on a larger skimmer it would be a lot more difficult though.

[CMcNeil]

im making one as well,i am using a sedra 3500 and the body will be 6" at the base and 2.5"neck.i already made the cone but need to trim it and put it all together.the cone is made from 3/16" clear PVC sheet that i welded then heated it and put over a form.here are some pics of the cone.

http://i20.photobucket.com/albums/b239/checkinhawk/Picture005.jpg

http://i20.photobucket.com/albums/b239/checkinhawk/Picture003-3.jpg

[Fishboy93]

that looks great! was the clear pvc sheet expensive?

[CMcNeil]

not really,it is less than acrylic.you may want to look into PETG sheet,from what ive seen that is what ATB uses for the body.

[alpine]

CMcNeil
Can we get a pic of the form you used?Would be interesting to see.

[CMcNeil]

i dont have a pic of the form.i cut two plates from 1/4"pvc sheet(one was cut to the tops od and the other was for the bottom od).i placed a piece of 1 1/4"sch80 pipe between them to get the height i wanted,that was all i did for the form.

[alpine]

I know what you did now,thanks for the quick reply.

[Fishboy93]

Thanks! I didn't know that I assumed ATB used acrylic thats great to know. Can PETG be glue with weld-on to acrylic?

[CMcNeil]

ATB welds the materials with a hot air welder.i dont know for sure if it can be glued,but i think IPS makes something to bond the 2 materials.i plan on hot air welding mine just like ATB did.

[Fishboy93]

<a href=showthread.php?s=&postid=11751604#post11751604 target=_blank>Originally posted</a> by liveforphysics
I'm extremely interested in having a large acrylic cone built for me. I require one about 3 times that size to be fabricated for me. If you find any good sources to make the cone, please contact me as I am ready to have one built.

Your skimmer design looks great! The properties of a cone migrating bubbles is a much better functioning shape than the typical cylinder with a cone on top.

Best Wishes,
-Luke

Thanks I'm only a junior in high school and am swamped in work/track right now so this might end up being a summer project but hopefully not. As far as someone building one for you you may want to contact:

http://www.polyfab.biz/plastic_cones_fabricate.htm

[Fishboy93]

Off IPS website:

4 - Non-flammable, water-thin, moderately fast setting, solvent cement for bonding acrylics. Also bonds styrene, butyrate, PETG , and polycarbonate to themselves. Will not bond to cross-linked acrylics.

[GuySmilie]

I posted this several weeks ago in another thread, but it's more relevant for this one.

For anyone interested in the layout mechanics of this type of skimmer, which is technically called the frustum of a cone, here is a simple and free layout pattern program (http://www.softpedia.com/get/Science-CAD/Cone-Layout.shtml) that will create a cut pattern for the acrylic body. You can dial in any dimensions you like. Just download and run. It installs as a free standing program on Windows machines.

[CMcNeil]

here is a link to the IPS selection guide,it tells you what glues work on what materials.
http://www.ipscorp.com/industrial/pdf/Industrial_SelectionGuide1206.pdf

here is where my cone skimmer stands as of today,i just need to add the collection cup and pump inlet and im done and ready to test.

http://i20.photobucket.com/albums/b239/checkinhawk/30g%20rimless/Picture014.jpg

http://i20.photobucket.com/albums/b239/checkinhawk/30g%20rimless/Picture013.jpg

http://i20.photobucket.com/albums/b239/checkinhawk/30g%20rimless/Picture012-1.jpg

[Fishboy93]

Wow! that looks great CMcNeil. How did you machine the parts for the base?

[Fishboy93]

does anyone think 17" is too short? I tried to build it to scale with the nano ATB skimmer but it seems so small.

[CMcNeil]

my cone is 6" base 2.5" neck and 14" tall.ive seen the medium and large models and they were only 22" and 23" tall total with cup i believe so 17" might be on track,mine will be about 22" when the cup is on.i machined the parts on a lathe and did the bubble plate with a drill press(BTW i work at a plastics fab shop)so all the materials and machines are at my disposal.

[alpine]

CMcNeil
You really needed to do a build thread on that one.I bet there are a ton of people who would of liked to see that skimmer being built.

Did you cnc the parts,or do them by hand with a router?

[alpine]

Sorry I didnt realize you had posted before me,wife had my attention for a few minutes and you snuck a post with my answer before I even posted the question.

[CMcNeil]

lathe and drill press are all i used.

[fade2black]

Looks like you plastic welded the parts together? PVC to acrylic? nice job, looks great! Did you make a form for the cone first?

[saltydragon]

anyone tried using a conical lab flask at the base for this type of skimmer?........its basically the same shape.....just need to find the right sized one...

[Fishboy93]

I think I'm going to extend the cone to 14" tall to have a greater reaction time and handle more air.

[CMcNeil]

<a href=showthread.php?s=&postid=11765999#post11765999 target=_blank>Originally posted</a> by Fishboy93
I think I'm going to extend the cone to 14" tall to have a greater reaction time and handle more air.

just wondering what your base OD and top OD are going to be?

[Fishboy93]

OD base: 6.5"
OD top: 3"

[miwoodar]

You guys suck. I was perfectly happy with my skimmer until I saw this thread.:)

[Fishboy93]

hahaha

[alpine]

<a href=showthread.php?s=&postid=11766742#post11766742 target=_blank>Originally posted</a> by miwoodar
You guys suck. I was perfectly happy with my skimmer until I saw this thread.:)

You think they suck,heck im still waiting for the diy write up with pics.

hint hint

[landragon]

Chris, are those poppin' fresh doughboy placemats?

[lvpd186]

<a href=showthread.php?s=&postid=11773282#post11773282 target=_blank>Originally posted</a> by alpine
You think they suck,heck im still waiting for the diy write up with pics.

hint hint

I second that. I would love to see a photo by photo write up for that skimmer (and the skimmer in the works for that matter)

[CMcNeil]

yes they are

[CMcNeil]

the biggest hurdle i see to DIYing this skimmer is 99% of you dont have a plastics welder.without the welder i cant see a way to make the cone.i do have mine finished and running and i will say i am VERY happy with what im seeing.i had a foam head instantly and it has pulled some stuff out(not real dark)but it is working.i also have to consider that the tank only has 2 small fish in it and i dont feed it heavy.im running a sedra 3500 and euroreef claims it pulled 420lph,i think it is pulling more air now with the lower head pressure on the pump.i am going to hook up anm air flow meter to it to find out the real number but i wont be able to do that till after the 15th of this month(vacation time).

here are some pics
http://i20.photobucket.com/albums/b239/checkinhawk/30g%20rimless/Picture209.jpg

http://i20.photobucket.com/albums/b239/checkinhawk/30g%20rimless/Picture211.jpg

[alpine]

I must be part of the 1% because I have 2 of them.Besides there are other ways of bonding plastics without a welder.

[Skepperz]

Would this be a good plastic welder for the job?

http://cgi.ebay.com/ebaymotors/5600HT-MINI-WELD-AIRLESS-PLASTIC-WELDER-Auto-Motorcycle_W0QQcmdZViewItemQQ_trksidZp1638Q2em122QQcategoryZ63702QQihZ009QQitemZ190195513024QQrdZ1QQ sspagenameZWD2V

[alpine]

CMcNeil
by the way,was just looking at the first pic you posted and I have to say that you got some really good welds going there.

It took me a while to get welds to look that good.Of course the parts I weld dont ever have nice straight or round lines for me to follow.

[Skepperz]

What other methods are there alpine?

[CMcNeil]

yes you can bond plastics without a welder,but you cant make the cone without it.no glue will hold up during the heating process to form the cone.thanks for the weld compliments(13+ years under the belt welding)

[alpine]

I didnt realize you welded the cone as well.I guess in that case you would need the welder.I have seen some acrylic sheet formed into tube before and they didnt weld it.I figured you didnt as well.The sheet was solvent cemented and then a brace in the inside and out were added to support the solvent weld.

You def got me beat,I barely been doing it for 6 yrs now.I do mostly abs as thats what motorcycle plastics are made of,but I have messed around with pvc in the past.

Any chance I could get a pic of the seam on the cone.I know how you made the form,and forming the sheet shouldnt be that bad.By the way what did you use to heat up the sheet to forming temp?

[GuySmilie]

<a href=showthread.php?s=&postid=11774820#post11774820 target=_blank>Originally posted</a> by CMcNeil
yes you can bond plastics without a welder,but you cant make the cone without it.no glue will hold up during the heating process to form the cone.thanks for the weld compliments(13+ years under the belt welding)
I don't think I buy into that theory.
You can form the cone before gluing.
The cone can be cut to shape from a sheet of acrylic using a pattern made from the program I posted about earlier in the thread. Then it can be heat-formed around a wooden jig. Once it cools, a bead of Weldon #16 would more than adequately seal the seam.

[CMcNeil]

<a href=showthread.php?s=&postid=11776581#post11776581 target=_blank>Originally posted</a> by GuySmilie
I don't think I buy into that theory.
You can form the cone before gluing.
The cone can be cut to shape from a sheet of acrylic using a pattern made from the program I posted about earlier in the thread. Then it can be heat-formed around a wooden jig. Once it cools, a bead of Weldon #16 would more than adequately seal the seam.

i can bet that the cone wont be round at all,trust me i have been making cones out of pvc for years,if it could be done any other way we would have done it by now.why do you think ATB made them the way they did?because they had too.

[slug]

Do you think a petg cone could be made the same way? I can get it a lot cheaper then opaque pvc.

So you bend the material around and weld it and then heat form it to a mold?

[CMcNeil]

i believe that ATB used PETG to make the cone so id have to say yes.i heated the material then folded it together to make the weld.then i welded it and let it cool,after it cooled i heated the whole piece and dropped it onto the form and let it cool.

[GuySmilie]

<a href=showthread.php?s=&postid=11776805#post11776805 target=_blank>Originally posted</a> by CMcNeil
i can bet that the cone wont be round at all,trust me i have been making cones out of pvc for years,if it could be done any other way we would have done it by now.why do you think ATB made them the way they did?because they had too.
Well I can't dispute you as I've never made a cone from a plastic before.
Made plenty of them from aluminum sheet stock, back in my Amateur Radio heydays.

But I do have limited experience with heat forming acrylic and it seems to me that it would not be all that difficult as long as you start with an accurate patten, have a true-to-form mold/model, and keep the leading and trailing edges aligned properly while working your way around the form with the heat gun.

I'm not familiar with how ATB makes theirs.
Please elaborate as I'm here to learn. :)

[Fishboy93]

I'm not planning on welding my cone, I am going to make a very accurate jig, and use a 1" strip of acrylic going up the seam to fill any gaps.

[Fishboy93]

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1281545

This guy got a QO2200 to pull 17 scfh is this about the right amount of air for my skimmer? I couldnt find anywhere to convert scfh to lph or lpm

[CMcNeil]

im not sure how much air is needed for it to work best,i dont have a gauge on mine yet and wont be able to till after the 15th of this month.i am running a sedra 3500 on mine and it looks good so far.i got some skimmate today(still greenish)but it did smell nasty.i also need to make a new diffuser plate,mine has too many exit holes in it and i have to close the outlet pipe almost completely to get it skimming the way i want.

fishboy93 have you started anything on the build yet?the form is easy and wont take you long.

[Fishboy93]

I can't start right now i don't have the cash or the time right now, hopefully i can make some money. If I have a free weekend or two i will start; howver i did get my buddy interested in the idea of one for his 75 so we will probly build two and it will be nice to have a helper.

[Fishboy93]

BTW i think i found my jig =)

http://www.officerstore.com/store/product.cfm/pid_5137_jbc_safety_plastics_18_traffic_cone_orange/

[hyperfocal]

Jig? Why not just use it as the cone? It's PVC, so should easily glue to a short riser...

[Fishboy93]

because i'm pretty sure its the really flexy pvc and besides its not clear what fun is a skimmer if you cant see the bubbles.

[GuySmilie]

<a href=showthread.php?s=&postid=11781645#post11781645 target=_blank>Originally posted</a> by Fishboy93
BTW i think i found my jig =)

http://www.officerstore.com/store/product.cfm/pid_5137_jbc_safety_plastics_18_traffic_cone_orange/
That would probably melt from the heat.........unless you covered it with a layer of fiber glass and resin.

Has anyone ever entertained the idea of building one of these skimmers like a 4-sided pyramid shape? Seems like the same 'concentration principle' would still be valid. Might not be as efficient, but would be a lot easier to build.

[hyperfocal]

Heh, got'cha :)

Flexi-PVC glues just as well as rigid though. I did notice the inside surface is textured, and that might mess with bubble size and flow.

[H20ENG]

Guy,
I've been thinking about it, but simply box shaped, with tapered sides.
Just havent had the time, as usual...

[liveforphysics]

Flex PVC does not glue well to hard PVC. Quite the opposite.

PVC welding is perhaps not the only possible way to skin the cat, but I think you would have a hard time finding a method that would be as functional and strong.

Working in the fluid-dynamics field professionally, I'm not seeing the use of truncated pyramids matching the migration interuption properties of a conventional cylinder/cone pairing. The whole beauty of the cone for foam migration is avoiding abrupt transition points and finding the minima of wetted area. Using a truncated pyramid is not going to give you either of these desireable effects.

That skimmer body looks as close to perfect as I've seen. It's very similar to the amazing KZ skimmer design. I like it, great job!

-Luke

[hyperfocal]

<a href=showthread.php?s=&postid=11783566#post11783566 target=_blank>Originally posted</a> by liveforphysics
Flex PVC does not glue well to hard PVC. Quite the opposite.


I guess there must be multiple types of flex PVC. Spa-Flex style glues to rigid PVC just fine, with the right glue.

[Fishboy93]

anyone have any comments about pumps for a skimmer this size i'm clueless..

[marspeed]

I once filled one of those safety cones with concrete now I have a concrete cone might make a good mold

[Fishboy93]

lucky, the buddy I'm building mine with did some boat repairs so he has some fiberglass around that i am going to wrap the cone in.

[jh2pizza]

Working in the fluid-dynamics field professionally, I'm not seeing the use of truncated pyramids matching the migration interuption properties of a conventional cylinder/cone pairing. The whole beauty of the cone for foam migration is avoiding abrupt transition points and finding the minima of wetted area. Using a truncated pyramid is not going to give you either of these desireable effects.

Yeah, what he said. lol


lost me, but could it be possible to make the cone out of fiberglass?

[alpine]

jh2pizza

A fiberglass cone skimmer huh.I dont see why not.Fudge here on RC built an entire skimmer out of fiberglass.Well at least the body was all fiberglass.

[flasher1]

cmcneil - how much would a fabric shop like yours charge to make a skimmer like this?

[landragon]

Chris, if you aren't on the slopes yet, stop by work tomorrow. I'll lend you my Dwyer SCFH meter. It's a full size one, and reads to 100.

[H20ENG]

I didnt know fabric shops made skimmers, just clothes. :lol: J/K

[fade2black]

<a href=showthread.php?s=&postid=11793348#post11793348 target=_blank>Originally posted</a> by H20ENG
I didnt know fabric shops made skimmers, just clothes. :lol: J/K

I thought the exact same thing :D

[flasher1]

haha...sorry, i meant to put plastic fabrication shop. Just goes to show you that studying for physics warps your mind

[CMcNeil]

ill have to get the air meter when i get home.i am at Loveland Ski Area right now and its snowing hard.i fly back in on thursday.

[flat broke]

Any further updates on this lately?

Chris

[dpieroni]

Hi, I am looking on doing a small cone like atb's..
I have some questions:
the diameter of the riser tube?
tall of the riser tube?
tall of the body without the riser tube?
I think the base is 6''..
someone who can provide me this info?
thanks in advance
diego

[ConcreteReefer]

Fishboy-

I started a thread about DIY cone skimmers a few months before this one.http://reefcentral.com/forums/showthread.php?s=&threadid=1238255

After pricing out Acrylic, Pumps, Time, & having a Fabricator build the "cone". I concluded it would only be a little more $$ for an ATB- Your welcome to come over and check it out if your still pursuing this project.

[JCTewks]

<a href=showthread.php?s=&postid=12306977#post12306977 target=_blank>Originally posted</a> by ConcreteReefer
Fishboy-

I started a thread about DIY cone skimmers a few months before this one.http://reefcentral.com/forums/showthread.php?s=&threadid=1238255

After pricing out Acrylic, Pumps, Time, & having a Fabricator build the "cone". I concluded it would only be a little more $$ for an ATB- Your welcome to come over and check it out if your still pursuing this project.

That's why all of the talk DIYing the cone. I'm going to be attempting this soon for a 12" base 7" neck 30"tall cone....I'll be sure to take lots of pics and post when I do it :D

[liveforphysics]

I'm also very interested in large acrylic cone fabrication.

Cone is the idea shape for foam migration.

[hahnmeister]

Im actually shocked that Spazz hasnt started making volcanoes with some very large cone bodies. Considering how he makes his existing bodies (bending two sheets into half cylinders and then welding together), he could use the same method to make a 4' tall cone. It would also eliminate the cone he has to make, as well as the flange, at the top of the cylinder... less parts in other words.

As for the Guy and H20, when I 'introduced' ATB way back when, I did post pics of the 'pyramid' skimmer... I would imagine its what you were talking about:
http://www.meerwasserinfo.at/phpBB2/viewtopic.php?t=550
http://www.meerwasserinfo.at/phpBB2/files/pyramid_small_size_181.jpg
http://www.meerwasserinfo.at/phpBB2/files/dscn5122_267.jpg
http://www.meerwasserinfo.at/phpBB2/files/bild_2_110.jpg
http://www.meerwasserinfo.at/phpBB2/files/bild_5_183.jpg
In that thread you can also see it go head to head against an ATI BM200 and kick the crap out of it with a 500lph eheim 1260 needlewheel.
http://www.meerwasserinfo.at/phpBB2/files/020807_115.jpg

[liveforphysics]

Pyramid is better than the conventional cylinder/cone pairing design, but still additional wetted perimeter vs single cone, and additional turbulence points for bubble collapse.

Cone is simply ideal for a skimmer. It also puzzles me that we don't see more of them. If it's all just manufacturing difficulty, I would expect someone with access to a CNC table router to jump on the opportunity.

[GuySmilie]

<a href=showthread.php?s=&postid=12311121#post12311121 target=_blank>Originally posted</a> by hahnmeister


As for the Guy and H20, when I 'introduced' ATB way back when, I did post pics of the 'pyramid' skimmer... I would imagine its what you were talking about:.....
Yes, that is precisely what I was thinking of.
I was calling it a four-sided pyramid. liveforphysics called it a truncated pyramid, which is actually what it is.

Obviously that was not the design they eventually went with, and I didn't translate the discussion to see why. I realize a true frustum shape is more effective, but from a DIY perspective, I feel it would be much easier for 'most' of us to fab a truncated (4-sided) pyramid. There would definitely be some concentrating effect, albeit not as much as a true frustum, due to the square corners. But I would think the pyramid would outperform the traditional cylinder, topped with just a short cone transition.

What was the main reason for ATB abandoning the pyramid design?

[liveforphysics]

Just a friendly FYI. :) Both truncated pyramid and truncated cone are frustums. The cone is just an infinately sided frustum. But to get even more fussy, deeper into math, the pyramid stops existing. There are only cones with different base shapes, the one we call pyramid being a square base right cone. :) Some math prof fish geek is smiling while everyone else groans "who cares". :P :) :D

Back to your question:
It would depend on a few factors like pump flow and CFM vs chamber neck and legnth, but I see the square base cone loading up with gunk in and near the corners. The bubble slurry is going to want to rotate in the body, and rotation in a square means lots of internal bubble re-arangement. Re-arangement with bubbles means lots of testing adhesion of surface tension. AKA, lots of bubbles will pop and leave goo in the body and water column.

I think it would be an improvement over the cylinders with cones on top that we see commonly, but perhaps ATB simply found a way to manufacture the superior circular base cone shape and dumped the square base cone.

[GuySmilie]

<a href=showthread.php?s=&postid=12313629#post12313629 target=_blank>Originally posted</a> by liveforphysics
.....perhaps ATB simply found a way to manufacture the superior circular base cone shape and dumped the square base cone.
I thought about that scenario as well.
Since my last post, I went back and translated that thread Hahn referenced. It was never mentioned why. Reinhard<sp> was definitely impressed with the truncated frustum, :twitch: as compared to the conventional cylinder design. Even lowered his NO3 and PO4 to unmeasurable limits.

Maybe Hahn will know the defining reason.