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Hardinge CHNC 4 retrofit

Is the small o-ring the one in the check valve? In the end of part J from the photograph in #77?
It is what I used but I still had a full flow leak. There was nothing in the assembly when I first opened it. It is not clear to me if there is a piece still in the cavity. The picture from the manual is not clear as to if it is an o-ring or more of a disk.

The full PDF for the air schematic is in the post above the picture with the green/orange lines.
 
I tried to look at that one earlier but that schematic is too small to see details clearly and it gets pixelated when I downloaded and zoom in....
There was a jpeg and I had that problem but the PDF allowed me to zoom in without losing any resolution
 

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So is the side missing from this piece or is it just the picture? From the parts picture it looks like it should have a flat but not be missing the side. Gary
 

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Yeah without really understanding how it works I would assume that slides inside the other piece to block the air going through the hole, but I don’t see how it could seal if it’s slotted.
 
It seals on the opposite side where the rubber is. Inside the brass piece is a seat. There is a spring that sits in a hole where the slots are to bias it forward. the rod sits between the plunger on the other side and the whole assembly gets pushed into a hole. On the manifold block there is a hole , sealed by an o-ring on the casting side and pressure pushes the check valve open when the turret spins
I am assuming the flats are are there to let some air pass so it doesn't stick - like when pushing a dowel into a hole. The item I haven't inspected yet is the Mead hair trigger toggle valve.
 
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Is this what your valve is?https://www.clippard.com/downloads/...ge Number/220-281 Modular Valves/Page 265.pdf

My understanding of how that schematic reads is:
So the air is coming in port 1 and going out to check valve and turret on port 8. Then it goes through the turret and back to exhaust through port 3 and 2. This is in the "normal" position of the valve. When the valve is activated the air would go in port 1 and out port 2, through the turret and STOP at the check valve.

Is whatever is supposed to be controlling the solenoid not working properly so it stays in the normal position and air is always passing through?

Also notice the schematic of the solenoid from the PDF has a typo on it compared to the one in this Clippard link, I was curious about that, that is why I wanted to see the blow up without the green and orange lines, something looked funny about it....
 
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I added links in my signature to two google photo albums. The one with air controls has pictures that may help get a better overview. I will try and made a video about the check valve and where it goes and the interfaces to the casting and manifold block for the solenoid
 
Is this what your valve is?https://www.clippard.com/downloads/PDF_Documents/Old Catalogs/2010 Catalog/Clippard 2010 Catalog by Page Number/220-281 Modular Valves/Page 265.pdf

My understanding of how that schematic reads is:
So the air is coming in port 1 and going out to check valve and turret on port 8. Then it goes through the turret and back to exhaust through port 3 and 2. This is in the "normal" position of the valve. When the valve is activated the air would go in port 1 and out port 2, through the turret and STOP at the check valve.

Is whatever is supposed to be controlling the solenoid not working properly so it stays in the normal position and air is always passing through?

Also notice the schematic of the solenoid from the PDF has a typo on it compared to the one in this Clippard link, I was curious about that, that is why I wanted to see the blow up without the green and orange lines, something looked funny about it....
 
Is this what your valve is?https://www.clippard.com/downloads/PDF_Documents/Old Catalogs/2010 Catalog/Clippard 2010 Catalog by Page Number/220-281 Modular Valves/Page 265.pdf

My understanding of how that schematic reads is:
So the air is coming in port 1 and going out to check valve and turret on port 8. Then it goes through the turret and back to exhaust through port 3 and 2. This is in the "normal" position of the valve. When the valve is activated the air would go in port 1 and out port 2, through the turret and STOP at the check valve.

Is whatever is supposed to be controlling the solenoid not working properly so it stays in the normal position and air is always passing through?

Also notice the schematic of the solenoid from the PDF has a typo on it compared to the one in this Clippard link, I was curious about that, that is why I wanted to see the blow up without the green and orange lines, something looked funny about it....
In the normal condition the turret is not turning. My situation is that there is constant air blowing out port 7 -basically full volume. When the turret spins air exits port 3. On the manifold block there are two holes on the top side - port 7 is the right one Port 3 is the left. It was my local Clippard rep that guided me to the check valve being faulty. My experience with air logic is minimal and there could be other problems but as I see it my logic matched the diagram in the PDF, in spite of it being for a CHNC III vs CHNC 4 which is an earlier version - yeah the numbers don't really tell the story. My machine is a 1983.
 
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I do not know if it should have a plug - as you said nothing should be coming out port 7. I have put my finger over the hole and flow stops - I can try a temporary plug.
I appreciate the flyer for the symbols. I ended up drawing the clippard valve upside down like the Hardinge drawing and numbering the ports to get a better understanding of what is happening. From the flyer it says line are drawn to the unactuated condition - so the box on the right...following the flow and assuming the check valve is leaking it says air would be coming out of port 7. I'm not clear on what is happening with the pilot valve do I need to add the line in red?air solenoid.png
 
I am not sure I understand the pneumatics, but I think I understand what has to happen from the mechanical standpoint.

The turret up and down has to be an air cylinder of sorts. You have to put air pressure under the plate to pop it up off the locks so it can spin.

Now as far as I know there are no return springs and gravity isn’t going to hold it tight enough to machine with, so once it is in position you must have to apply pressure to the top of the plate to lock it down and hold it. I assume the top pressure is constant, so if the cylinder itself is leaking you would get air from the top to the bottom all the time which looks like it’s open to port 7.

I could bevand probably am wrong, but from the mechanical standpoint I can’t see any other way it can work.

Gary
 

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There is a turret stop/lock - I believe it's main purpose is to stop the rotary motion but could it be possible that it also holds it down.
I sent you a manual via PM...and when I looked at the check valve here is what it showed... The big difference is the connecting rod that actuates the valve...item 35 appears to be a single piece vs the two items I have... and it does show an o-ring on item 38check valve parts.png
 








 
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