RCABS pumps

[Kazzer]

Some people have asked, are our LPB pumps good enough for RCABS. Of course the competition says not, but well, I think they are pumping hot air!

See for yourself!

http://www.moonrakers.com/submarines/RCABSpump.mov

[junglelord]

Hi Mike.
My first attempt at an RC Sub was the Robbe SeaWolf V2. I have only made tub tests on it and its good to go.
It was four pounds on the first test. This 2nd test was just perfect and straight as an arrow. Its weight is 5pds.



Back before I was aware of the SNORT system I found a guy who had used a water pump to pull water into a bladder bag for static dive for this model and asked questions from people with this sub.

http://www.rcgroups.com/forums/showthread.php?t=302419

I had not decided what way to go other then the dynamic dive that it already is but wanted to set up some type of static effect. I did read about RCABS and was interested in that one as well. So I ordered a pump.

It is a RCABS Micro air-pump by Smart Pumps Inc
6v dc, 450mA @ 300 mmHG
Its only got one outlet.



Here is the SeaWolf opened up. The front hull has a microservo for the front drive planes. The two rear servos for the rudder and rear dive plane are in the center frame. Only thing missing is the battery which I stabilize with an elastic in the center of the frame. Its just a simple Simple RC 3 Channel Receiver at the back, Electronic Speed Control in the middle, three servos and battery. The Water Tight Compartment screws together from the front. I was told that the antenna could be run inside, so that is what the wire is that is taped to the innear frame.




What if anything can I do with this pump other then RCABS. The single outlet is a limiting factor I believe. To tell you the truth not sure I could make my SeaWolf RCABS anyway as the front and rear wet areas may not have enough space. Is this pump useless to me? Can I use it for a SNORT?

I do like the internal bladder by Big Sax with water to make this static dive. Here is the internal bladder bag video from Big Sax. Excellent performance.

http://www.dailymotion.com/video/x2b4my_seawolf-robbe_sport

I do have video of it as dyanmic. Its quite fast. It has a 600 motor.

http://ca.youtube.com/watch?v=S1SmiSg8mBw&feature=related

http://ca.youtube.com/watch?v=LnoNbA0UICU&feature=related

Could a SNORT system be set up for this unit? The internal bladder bag may be the better option.
Wonder what you think or if anyone has an opinion.
Thanks.

[Kazzer]

I guess you could put a static dive system in it, but you'd have to pull all the electronics out and put them in a Sub-driver. Then you'd need to drill holes in the hull to let the inside of the boat flood.
I suspect the reason it goes so fast, (doesn't look very realistic at that speed me thinks) is to push the very buoyant body under the water.

Is the entire hull body full of air? If so, I doubt you'd get enough space inside to place just a bladder.

I think it's easier to start over with the hull, rip the guts out and you'd have a winner.

Here is an article on establishing surface trim

http://support.caswellplating.com/index.php?_m=downloads&_a=viewdownload&downloaditemid=120&nav=0,5,6

Any other suggestions?

[junglelord]

Thanks Mike, I apprciated that link, I had not read that one.
It will be good for my SeaView. I think I have researched it all.

It seems to me that the SeaWolf will stay dynamic for now.
I could never shred it and start over...I am not that type.
I am proud of it and I apprciate your enthusiasm.
Remember I am new at this....
:p

If I make it static, I will get the water pump and bladder bag as per Big Sax.
His system works great for that particular model. The urine bladder bags are thick enough not to leak (never say never). Big Sax has never had a leak on his. You suck water into the bladder bag and let it flow out as you wish when you wish. This is his scheme.




Pretty simple and very effective as his video shows.
http://www.dailymotion.com/video/x2b4my_seawolf-robbe_sport

Only the fore and aft ends and the upper portion of the central WTC flood as you can see in the photo below. There is a lot of room inside my unit for the bladder bag to sit over the 7.2 battery which is much smaller then the dry lead acid sealed block batteried suggest. If you look above at my setup photos, I have a lot of room in the center. The empty central space is due to me not using the suggested large block battery and therefore also being able to position my servos in a better spot too.

The pics below show a 400 motor for the water pump placed under the frame circled in red. This is Big Saxs unit, not mine. In the photo below Sax still had room for the bladder above the block type battery. This means I will have no issues with space and if I convert my bladder bag will be half way down in the hull for a better CG although this worked fine for Big Sax.


I do however need a four channel for that...and that will be on hold as my SeaView radio/receiver are more important right now. The three channel will do good for now.


I guess I have an air pump to sell to the RCABS group.
Crack That WHip

[Kazzer]

Here are our bladders - with sizes.
These have two tubes attached to each one.

http://www.caswellplating.com/models/bladders.html

Try that ole Smart pump. It may pump water for you. Just wire it up to a battery and drop it in a tank for an hour or so. I'll bet it'll work.

What did they use as a valve to let let the water out of the bladder?

[junglelord]

HI Mike
:)

This being a single port pump would as you indicate require it being submerged.
That is not practicle in my setup. I thankyou for you knowledge.
I will sell it off and get a internal pump with two ports if I convert this vessel.
Thanks so much.

[Kazzer]

Darn! I just wanted to see if it would blow up!
Devilish

[junglelord]

Hey Mike, thats a fun idea...but I am on a pension and hate to see money go up in smoke.
Censored

But I paid I think $18 or something for it. No more then $25. I know I got a limited supply pump or something to that effect. I will send it to you in exchange for a credit towards my Seaview Snort. You can do what you want with it, put it on youtube and watch it pump or squeel like a pig.
Crack That WHip

[junglelord]

What did they use as a valve to let let the water out of the bladder?

Basicly the diagram above shows an "IN" which is a two way valve actually. The second valve is a one way valve which is incase of overfill from a runaway motor. The motor runs both ways on a three way switch. The two valves are from aquarium shops for fish and cost about $2.

Here is the information on that question to Big Sax. Forgive the reply as it was translated.

My system is too simple, two rubber bag (pediatric bags for urine) over the components and filled/emptied from a modified robbe pump with speed 400 6V, in order to dive its require approximately 250/300 grams...I have 2 bags for total 250cc but at 150/200cc the sub dive static,

>1.Can the 6V robbe water pump operate in both directions, i.e pump water into and drain water out of tank?

Yes, the pump works filling up or drain water out of tank, I have connected a simple "Duo switch robbe" to a channel of the radio (with a 3 position switch) it supplies to make to turn the motor in the two senses being filled up or emptying.(The pump has two gears that turning in a sense send the water within and inverting the sense they send it outside.)

>2.when the boat surfaces, the water should be pumped out from the tank, but there may be a pressure difference between tank and sea depth, so will this problem affect >the pumping process?

...no, the pump is too strong

should I install the one way valve at the inlet? Where can I find these type of valve?

yes I installed a income water filter (on italian: ingresso acqua) and a oneway valve for the rubber-tank overpressure (valvola di non ritorno) ... this is the scheme:

http://www.saxxx.it/sub/imgsub/sw_schema.jpg

I am a fish-tank entusiast and the one way valve is a simple (and ultraeconomic) acquarium valve for air-bubble also the water-filter income e' from fish-tank, is a simply air-stone ... all two just 1/2 dollars ....the one way valve is a security optional, for me not optional....,in normal condition I stop pump when the sub dives (as soon when water bathes the bridge) but if you ave a failure the pump is out of control and if not ave a valve the bags burst and water fills up the sub... sinking it!!!

For one way valve I used a simply acquarium air valve for 2 dollars, the sub coast a lot more also my IN filter is a acquarium airstone.




Is there a valve inside the pump so that when the pump is off, no water can enter the bags?

no... but not going beyond the 2/3 meters the water pressure is insufficient in order to pass the pump and to fill up the bags, indeed the elasticity of the bags always stretches to make to exit the water and to emerge, much better!

http://www.rcgroups.com/forums/showthread.php?t=302419&page=2

[Slats]

Hi JungleLord....

The Robbe Seawolf was my first RC sub....some decade plus back.
Its a fine submarine model and the latest evolution has made it easier to get to the innards etc. I loved mine - its a fun boat that I passed around to new guys in my RC boat club to experience some basic RC submarining.

If the intention you have is to modify it to take on board a RCABS or for that matter any other ballast system, you are talking major surgery - that I would never try. Why? This boat is a dry boat, in that it has very little free flood area, but also in this boat the pressure hull forms the basis of holding the external ABS outer shell together. RCABS works by acting on a volume of water within the submarine - so you would need to some how make part of the available real estate -currently occupied by the pressure hull available to free flood and the bag inflation would then force this water out. It is not impossible but it will be within the confines of the existing pressure hull major work.

If you want to go to a RCABS; or any other static dive system in this sub the easiest way to proceed is really a new pressure hull setup (which is going to be difficult as, as stated above.... the current pressure hull forms the basis of holding the external ABS outer shell together.

If it were me - I'd keep my Robbe Seawolf as is and I would start saving for something else.

Mike has an absolute steal of a package on his website - check out the Skipjack model and its accompanying subdriver. Its around the same size as the Robbe Seawolf. Its a true scale model with a fantastic dive system.

Best
John

[junglelord]

Hi Slats
Thanks so much for the comments.
I will keep it original for this summer for sure and probably for good.
If it gets modified, it will be as mentioned, with internal bladder for water which requires only two openings on the front or rear end cap for the two valves mentioned. The hassel is the need for a new radio system at that point as well...or else it would be a economical venture...but I got money tied up in other ideas...Ideas you mentioned but in this direction.


I am actually going to make two SeaViews. I look forward to the dream of a SeaView and a SeaWolf on prowel together this summer.
I'll drink to THAT!