Re: Volvo EC300D
 

I made up this planetary drive for my jung pump out of some stuff I had lying around(cough..hoarder). It ain't pretty but neither am I!:p I'm not sure how this will workout because I don't have a valve block yet but it seems to build enough pressure to split hoses without slowing down:eek: hehe oops! 30bar is no problem... I've run it with three cylinders going at once and it seems like its OK for speed but it might be too slow once I'm running it all at once. Time will tell...


Reg

Re: Volvo EC300D
 

Hey Reg, that's a neat idea! and no expensive belt's to fuss with. I'm looking forward to seeing the beast in action! Will you take a picture of the pump, with the standard unit of measure? pop can or beer bottle. Tape measure take's the fun out of it!
Cheer's, Neil.

Re: Volvo EC300D
 

Good work Reg

Is the motor and planatary from a drill ?

greg

Re: Volvo EC300D
 

That didn't take you long to figure something out. Nice work.

Re: Volvo EC300D
 

This machine looks as good as the hi-dollar models that are out there! Guess the proof will be when you get it "in the dirt". Good job.

Re: Volvo EC300D
 

Maybe.... LOL It's a strange set up but it ended up working OK at least as far as the hook up is concerned. It pumps a huge amount of pressure without labouring but only time will tell if it turns fast enough to move enough oil for the size of the cylinders. I made a belt drive set up too using some stuff that I had but the pulleys didn't provide enough reduction and the motor would stall at 18bar so I went on to build this. The valve block should be finished today or tomorrow so I really have my fingers crossed that it all works. It's been nearly five months since I started this build and I wanna play!

Thanks for the compliments guys!

Re: Volvo EC300D
 

I really like your build, very clean and precise!

How did you installed the windows? Just cut them very accurately and glued into the "pocket"? It's just that the windows look good and I'm searching for ideas on my build.

So you made all your hydraulics by yourself?

Re: Volvo EC300D
 

Thanks,

Yes the windows are cut slightly larger than the cut out, and glued in place on this model.

I can't take any credit for the hydraulics other than making the drive for the pump. The pump itself is a Jung, and the cylinders and valve block were made by my Father-inlaw.

Reg

Re: Volvo EC300D
 

My father inlaw finished the pieces of the valve block today. I have to do a couple things and then assemble it. Hopefully it works:confused:

Reg

Re: Volvo EC300D
 

Whoa! Nice valves you've got! I hope it works out for you, I like when people try to make their own hydraulics because buying them is 5 times more expensive!

I googled Jung but I didn't find any site related to this pump, can you give a specific link?

Re: Volvo EC300D
 

its http://www.jung-fluid.de but i think site is down at moment or at least i cant access it, they dont have prices on there you have to email but they are reasonably priced, the 0.3ccm pump which is in the vario excavators they quoted me 74 euros + tax and shipping and the 0.46cc was 80euro plus tax.

Re: Volvo EC300D
 

Okay, thanks! I hope this site will be back soon. Prices seem reasonable, I've got quotes like 200-300 euros, I don't remember these sites though. Do you have any idea of their cylinder prices?

Re: Volvo EC300D
 

So I've been wrestling a big problem with my valves... The one my Father inlaw made is very nice and it works perfectly(the bucket will stay up for days) BUT... it is large and at 30bar it is impossible to turn without pliers. I spent 12 hours the day before yesterday making my own valve from scatch that is much smaller and it does work a lot better but it is still stiff considering the size of it.

What am I missing???? There must be something simple that is done to this style valve that allows them to turn more freely under pressure. I tried drilling a small hole in the oil passage way on the pressure side of the plug(valve) to allow oil pressure into the top of the valve body but it didn't seen to help.

Does anyone know what we are not doing that needs to be done? Any help would be appreciated!!!


Thanks Reg

Re: Volvo EC300D
 

Reg, the only suggestion that I would make is to change from the round actuators on the spools to leavers. If you stagger the height of the arms then you could run every other spool with two servos on each side instead of direct drive. Then make the arms as long as needed to get the torque to move the valves. Hope this makes sense.
Rob

Re: Volvo EC300D
 

Could your problem be something simple like come in the side and go out the top. You have every thing coming in the top and out the top and that seems to load the valve on one side and binds it. Ed

Re: Volvo EC300D
 

Reg , dumb ? , do your valves turn with ease with no pressure ? Could be just a little lapping needed . I have a Robbe valve that is tight like that till I loosen up the top .

Re: Volvo EC300D
 

The valves turn with very little resistance with no pressure. They actually turn decent when their open too, it's just when you are trying to open them from the fully closed position or close them from the open position that they are too stiff. Have you had your Robbe valve apart? Does it look much different than what we're doin? I think that Ed is right and it is side loading the plug. I have some of my grandfathers hydraulic books and in them it says that rotary valves are hard to balance but there has to be a way!:confused:


Thanks for the help guys!

I just recieved some parts for my Tigercat so....

Re: Volvo EC300D
 

Reg , the Robbe valve is exactly what your doing . I'm thinking you have more pressure then you need . do you have a pressure relief valve in somewhere ? If not , put 1 on the supply circuit after the valve . come out where the plug is ( assuming thats the supply side of your valve ) I haven't got to play with the stuff from Richard yet , but I plan to make a solid base for the valves much like the verio setup . they bring the supply from the pump through the valve into a pressure relief valve of some sort ( needle valve I think ) .

Re: Volvo EC300D
 

Thats interesting to know that they are the same. I do have a relief valve and it's set at about 28 bar. At 20 bar this machine doesn't have a lot of power but the valves do turn much easier. I would like to be able to dig firm ground with it so I think 25-30 bar is necessary. Do you know the diameter of the valve?

Thanks Reg

Re: Volvo EC300D
 

the ports under the rotor are .320" center to center . the rotor is .510" dia the crescents are the same as the ports . I'm going to build a 385cl cat which is as big as vario's 850 deere . I'm not sure these Robbe valves are big enough :confused: the ports seem to small for the flow needed ( about 1 mm dia ) :confused: I may be making my own .

Stevie