Miniature Hydraulics - How and why!

[AQUASUB]

Its my second nature to push till i get what i want ,its called perseverance.You are welcome!

Dave

[kanoni]

It works ! The guy in the other store told me that it would take 2 days to arrive and will cost me all together about 11 $ . Thank you for pushing the issue .

[kanoni]

I will try again in a different store just in case i talk in to a "smiley " person and i will let you know tomorrow .

[AQUASUB]

I find that odd I can get this pump right here in this little towns Napa Auto store just ask for that pump or the cheaper one,they get it from up north also no charge in 2 days.
I have tried dozens of pumps for this perpose and this one beats them all in all aspects.
Dave

[kanoni]

Thank you very much for the part number . I contact the napa store in my town and they told me that it have to come from indiana . I live in CT and the cost of shiping will be about 10 $ plus the cost of the part . For that money i could get one from casswell site and it could be ok . I will try the lego cylinders and i will let you know how this will work out . Thank you again for your time and ideas . I will be in contact with you in case i will have more questions .

[AQUASUB]

The Napa part # is ATM 1582807 for the front washer pump ,there is the rear one it is the same ,but ask for the cheaper one its around 8.50$ and works as well as the more expensive one.


The other ones are far more expensive or hard to buy.

[kanoni]

Thank you very much for your fast responce Dave . I will use your system with the 2 micro switches and the servo as it is more simble than use a valve . I went in napa this afternoon and they had no idea what i was talking about . Do you please have a protuct number for that windshield gear pump ? It would be very usefull . Thank you very much for your time and idea . I will wait for your answear .

[AQUASUB]

You are welcome!
First yes the pump will pump the same PSI in both directions and can be connected to either a ESC to regulate the flow or speed very precisely along with stop and reverse,or directly to a reversing servo switch.I use allot of both depending on the application in your case you want to use 10 doors or actuators individually,I did it with just 2 and works very well,also on the Engel Typhoon along with masts.
I would suggest for the doors that 2 pumps be used that way it will work with more psi ,you can make two separate hydraulic systems activated by one Chanel and then you will see how scalelike the operation is the doors will not all close at once but will slowly close individually just like the full size sub does!
You can use for the counter syringes the larger ones so that you have like a 5 to one ratio for example ,that way less space is used and the pump does not have to work so hard to move a large number of syringes.
Also look into the Lego air actuator shown ,by adding a larger bottom nipple it is converted to hydraulics use,and they work very niclly and are a quality item,get them at Bricklink.com ,they are set up the same as syringes,the nice thing about them is that they have the pivot points on both ends just like a hydraulic ram.With the vast range of Lego parts a super realistic operating hydraulic system can be built with a very little cash.

The pump has to be sealed with Goop if it is going into the wet,by simply cutting off the terminal shield then sealing the terminals after soldering and the pump head and rear case by the terminals also must be sealed.
Use 12 volts to get maximum psi.

A simple reversing switch can be made with any servo,it also isolates the power systems from the radio system and will even work for quite some time if flooded!Just glue 2 micro servos to a servo clamped in place,be sure that they are positioned so that the double arm of the servo comes into good positive contact with the micro switch.

ESC use is the best and a cheap one like the Pro Boat blue ones work very well.But if you have allot of rams to operate than a servo reversing switch will do the job just as well without costing more.If your operating say a few masts then a ESC must be used as they will move too fast.

Have fun for you are entering the world of mini hydraulics and the possibilities are endless!

Dave

[kanoni]

Thank you very much for the info on the pump . I am working on a similar project for opening misseles doors on a typhoon that i am building now . My goal is to run one pump back and forth to open and close 10 sets of 2 doors 1 set at the time . Will that pump work both directions if i chance the polarity of the motor ? Did you used Goop to seal the terminals ? or the back plate of the motor ? Thanks again

[AQUASUB]

I will try that ,so far the water soap mix also causes binding.

[Scott T]

What do you think about putting some liquid soap between the two wiping seals on the plunger?
The soap would lubricate the walls of the syringe but not be washed away or diluted in the hydraulic fluid (water).
Drill a filling hole on a portion of unused syringe wall. Locate the plunger so it allows you to fill between the seals
through the hole. Now when you push past the fill hole the soap will be ready to lubricate the walls.

Scott

[AQUASUB]

I have an update ,the oils are out and just water is in ,the water does the job just fine,I will try with some detergent like Ivory liquid soap ,it might make it even more slick.


Dave

[AQUASUB]

I have not used Cod Liver Oil mainly because it smells nasty,Peanut Oil has virtually no oder.The fat is mostly at the top of the container so probably a small amount is emulsified in the oil and it does make a difference in slickness,the molecule is different some how.For centuries animal fats lubricated everything where needed and without being toxic.

If there is any trace of mineral oils the silicone tubbing and the syringes will swell and cause them to jam.Same goes for silicone based fluids.
The fluid must be completely inert to silicone and the plastic and rubber plungers.I do not know if the fuid in the roof system would work ,find out what it is?

Those pneumatics cylinders can be used as well but are not as flexable in that they can not be cut to any size and cost much more, and are much heavier,plus I do not know what fluids would be compatible.

So far this is the best non toxic fluid that after long periods of not being used does not cause the swelling.It also cleans up with just soapy water.
I might try air compressor oil next.
Dave

[Kazzer]

................. and peanut oil and animal fat works the smoothest, tried just Peanut Oil and was not as smooth.

Dave

I wonder if something like Cod Liver Oil and peanut oil would work? I somehow don't fancy the drippings from the turkey inside the boat. I noticed in my convertible car that the roof catch above the windshield has a hydraulic pump working it. Perhaps the fluid in there would work too?

[AQUASUB]

Yes that is the gear pump mentioned above, it will pump quite fast and strong at 12v and at 6v a nice scale-like operation. I developed it about 2 years ago.

The best performance is with an ESC that has equal range in both directions,very smooth and extremely slow operation can be obtained or fast as needed.
The pistons bottom out preventing any further movement can be adjusted by just how much throw one needs. It can be just 1 cm to a full syringe, just add or subtract the fluid with one bottomed out, it will always return to exactly the same point no matter how long the stick is commanding it to go on.The pump just allows for blow by and no harm to the pump or lines since the pressure is in the negative on the bottom side, so silicone lines can be used with barbs. I add a small ring barb made with a dremel on each tip, this adds a grip for the tube.

For long runs of tubing I use Versa tubing. It is aluminum aircraft grade tubing that is very flexible, light and easy to handle and cheap.

You bet the possibilities are endless here, even air cylinders or Lego air cylinders. Try it do as I did with an ESC and you will see just how nice this system works.

A note - the smallest one cm syringes do not work, only the next larger ones, and peanut oil and animal fat works the smoothest, tried just Peanut Oil and was not as smooth.

From doors, masts, hydraulic arms, folding wings, control planes, the possibilities are now obtainable with this - the ultimate linear servo.

Dave