1/8 BSPP or 8mm

[Corvid_hunter]

What is the difference between these two and if I wanted to get a 1 way check valve for my Yong Heng to put between the filter and the tank I'm filling, which one would I get?

Edit to add...I think I figured out the 1/8 BSPP is likely the thread on the male end and 8mm the foster size?

 

[Healthservices]

One would not fit the other.



British standard pipe. Vs. National pipe thread.

 

[Healthservices]

And it's possible you can have metric pipe thread too. I think, 10 × 1 and 8 x 1

 

[Healthservices]

But best to measure as I bought a lot wrong fittings. Only good thing is I have an example of each now to check. Lol

 

[Healthservices]

But I do believe 8mm is pretty much right for foster. But just a guess would be 10 x 1 for fitting size and ether a delrin o ring (flat washer) low in hole or rubber o ring high on threads, one or the other depending on how female end is cut.

 

[Eaglebeak]

If you want to put the check fitting between the filter and the tank you will need to mount it in the direction of the foster connector facing the filter and the threaded end towards your tank. The check valve only works in one direction. The type of thread that you need to order depends on the fitting that you intend on joining it to. An easy way of just making a portable valve is to connect the check fitting to an ordinary male or female foster with a matching female thread. If you make one as a male to male it will work in both directions by just inverting the orientation of the assembly. It's a good idea to mark the flow direction with an arrow to avoid confusion later. If you want to make the fitting with a male on one end and a female on the other so that it will fit in-between an already established union, you will be restricted in the direction of the flow to only one way. The direction of the flow with these check valves can only flow from the foster end to the threaded end. It is also important that there is a bleed valve between the check and the tank. Here are some examples of the ones I made.

I tried to make this as simple as possible. Always figure out exactly what you want to do and what type of threads you will need before ordering anything. I'm seeing a lot of examples of these simple mistakes made by novices recently. By all means, ask the questions but if you ask the wrong questions you are more likely to get the wrong answers. Even if you ask the right questions many of the answers will be half-truths or total nonsense. 

 

[Corvid_hunter]

The way I see it a check valve would be a good idea as it would allow the compressor to start without a load and then build up to what the tank has in it. Is this a correct assumption?

 

[Guest]

Your compressor isn't under load when you plug into the gun as a rule from what I've seen

 

[Corvid_hunter]

I'm filling a 6.8L tank.

 

[Kevin23]

What is the difference between these two and if I wanted to get a 1 way check valve for my Yong Heng to put between the filter and the tank I'm filling, which one would I get?

Edit to add...I think I figured out the 1/8 BSPP is likely the thread on the male end and 8mm the foster size?

Correct

 

[Eaglebeak]

The way I see it a check valve would be a good idea as it would allow the compressor to start without a load and then build up to what the tank has in it. Is this a correct assumption?

Your assumption is correct but I consider this reason to be secondary. You can do this manually. The valve just automates the process. The main advantage of having a non-return valve at the tank like the DIN 300 fitting in my photo, is if my line back to the compressor springs a leak in any of its joints or hoses and I am not in the room watching it, I don't lose a tank full of air. Believe me, it happens.