Another SCWD MOD

coralnut99,

Thanks for the compliment and the nomination. I hope this will save someone from having to buy a new one so they can spend their money elsewhere.
 
SCWD MOD Overdone

SCWD MOD Overdone

I have done another MOD. This is way overdone. I have not tested the flow before the MOD or in gph after the MOD. No time today. I added a 1 inch input to the top of a SCWD. The valves allow the switching time to be adjusted. I also drilled the outputs to 1/2 inch. With a RIO 32hf (1920 GPH @ 1ft) it will pump water out of a container faster than my garden hose will run it in.


89031Overdone01.jpg
 
Giovanni,

I did essentially the same thing with the tuning/control loop you've shown and have been running it for the past four or five days and really like the control it gives me over the cycle rate.

I'm not going for the high flow rate your're using so the increase to 1/2" from the original 7/16" for the side arms was enough for me. Have you given any consideration to removing the side arms completely and replacing them with 3/4" pvc connectors?

Jay
 
Jay,

Sorry for the deley in response. My wife gave birth to my second Son 5/22/06 at 02:19, so I have been a little busy. ;) When I get some time I plan to replace the side arms with some ABS threaded adapters of some larger size. PVC doesn't glue to ABS very well. When I see this works, I will even add one or two more outputs. I am glad you like the MOD and it is working well.
 
Wow the last week has been busy. Not sure what this kid has against sleep. HEHE. Has anyone tried any of my mods other than Jaygar?

Let me know how it is going and if I need to do anything different.

I have not been able to locate any 1" ABS fittings so I am looking into glue that will bond PVC to ABS to add 1" outputs.
 
AWSOME job ICURN !
CONGRADULATIONS ON YOUR NEW BABY !!!!
Looking forward to reading more about the new MOD and your new baby too!!
 
Re: SCWD MOD Overdone

Re: SCWD MOD Overdone

Congrats ICURN!!

A thought from someone who has never held a SCWD in his hand nor seen one (though your pics have been excellent and I think I get it)

It seems the only indespensible part of the SCWD is the gear box and the tapered inlet that houses it.

Youv'e devised a brilliant way to send as much flow into the device from the top as the midsection/outputs can handle while adjusting flow through the bottom/traditional input as needed to get the cycling rate you want. The bottle-neck is the midsection/outputs.

Why not take off the mid section too?


Who says the valve can only be 3/4" tall? Look at that white piece. Why must it be shortened at all?


<a href=showthread.php?s=&postid=7359602#post7359602 target=_blank>Originally posted</a> by ICURN
5. Now mark a line 3/4 inch from the bottom all the way around the plug. I did this buy using the old drum a rest for my pen and turning the plug 360 degrees.
89031DSC01515.jpg


Imagine a tall rotating valve (perhaps taller even than could be made from the piece in your pic) inside an abs sleeve with a (dizzying?) array of outlets of any size/number that will fit in the circumference/unlimited?length.

The top would otherwise be unchanged from:




THus you would have a device that could handle as much flow as your pump and midsection could handle, shunting off just emough to go into the gear-box end to get the cycling rate you want.

Waddaya think?
 
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there's another scwd thread that only reuses the impeller. the body and drum are made from whatever size pvc you want.

i'd toss the link out, but i can't find it right now.
 
brackishdude,

Your photo was freaking me out. HEHE. I do like your idea, very nice. It actually gives me another idea of how to put more flow in. The ports in the very top could be inputs for a more elegant design. In fact I think I have just solved the ABS to PVC problem when adding 1" outputs. Well it will be back to Lowe's in the AM and maybe more to come in this thread.

jpfelix,

At this rate I may be headed in that direction. I hope you can find the thread. I did a search and could not find it. I would love to see how others are doing things. We maybe able to combine ideas for the ultimate SCWD.
 
Congrats on the kid, fun times ahead!

Now, assuming you wanted to keep the body short, and make say 4-6 fittings all "fire" at different times rather than 3 at a time as in the pic, it'd be just as simple as dividing 360* by the number of outputs and cut the wedge out the resulting angle correct? Basicly 6 outputs, each fire on their own, each 60* apart, so you'd only cut a 60* wedge out of the center piece right? I'm thinking basically this would keep you from having to keep from forcing 1200 GPH out of 1 or 2 holes to get a resulting wave, and constructive interference would actually give you a better wave result in the end. I'll try and whip up a pic of what I'm talking about.

My other question is this, do you find that you have to worry about putting more water in the top than the bottom? You'd think that once the flow approached 50/50 the thing would just stop, then once the top inlet overcame that split it would start to spin backwards. Basically making it impossible to flow any more for the given pump. Moreso, the inlet flow being what it is will be the ultimate conveyor of how much water this puppy can swallow. I'd say 190% of the inlet flow would be about the stopping point?

Great thread, btw, I've got a brand new, never even had water in it SCWD in the box I practically stole from my LFS (They said they didn't have a market for it, and sold it to me for $20, stickered at $45) I think before I even hook it up I'm going to mad doctor it up like you suggest here. With my afformentioned twist of course. (It's going in a 210 and I need to make BIG waves :D )
 
god910,

I see what you are saying about the split inputs. What you have to remember is they are fed by the same pump in my design. This means there would never be reverse flow in either input. Resistance, pressure and velocity are the driving forces for adjusting the inputs and thus the switching times.

If I leave the two ball valves wide open, there is a great deal more resistance to flow in the impeller input side than the new top input. This means very little flow through the impeller side if any at all. This is also due to the output resistance being greater than the total input resistance. I use the ball valve on the 1" input to create resistance and force more flow through the impeller side. This increase flow though the impeller decreases the switching time. I use the small ball valve to fine tune the switching time.

It is late so sorry if I did not explain this well. Just ask questions and I will clarify later.

Just as you suggested, I am planning to add two more outputs iat the same level and have them switch in alternating pairs. 1 & 3 then 2 & 4. They will be at lease 3/4" so flow will be good. I may go to 1" just for the over the top types of which I am sure you are not one of, but I am sure you know someone who is. HEHE ;)
 
Does this mod allow more flow? Check out my setup. I got them hooked up to a BlueLine 70. The pump runs at 1750 gallons per hour.

p8190226mu1.jpg
 
Not realy gona help with flow.

Very nice setup. I see you have a bulkhead in the overflow box. What is that for, is the bottom of the tank not drilled?
 
Thanks all of you. Great thread. You have saved my dead scwd. I will attempt this very soon. Tuning multiport and all. Great brainwork!
 
I'm way behind here but I've attacked my broken SCWD with the dremel to start the process. Thanks so much for a great thread.
 
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