Im confused why this delrin does not seal the fill whips they are m10x1 it leaks like it cant even get to 100 psi on handpumpit all leaks out so fast.

[MarksmanPete]

As you can see in the pictures the same kind on the yong heng black filter end I used a delrin to seal it for some reason these dont work with the delrin o rings but seals with the washers. Im trying to figure out why it does not seal as I dont wanna tighten it down to the point when it deforms the delrin seal, Seems to do nothing when I snug it strange I also tried sealing with the other one you can see being used from the end of the black filter an it also leaked I dont know why the washer seals it but the delrin wont whats going on? .

 

[DpMarks24]

Hello every manmade synthetic has a duro # created by dupint.
Make sure to use the correct material, dm me I've bought some from a supplier. Try UHMW next. Delrin is extra long wearing and this very hard does not seal it's used as a wear guide or bearing material that is wearable.

 

[Heavyopp]

Is the threaded portion on the male end long enough to reach the delrin?

 

[DpMarks24]

Make sure to use the correct durometer material. Try UHMW next. Delrin is extra long wearing, and this means very hard, does not seal, it's used as a wear guide or bearing material. Ask hillairgun to make you a seal if you can't buy.

 

[MarksmanPete]

Make sure to use the correct durometer material. Try UHMW next. Delrin is extra long wearing, and this means very hard, does not seal, it's used as a wear guide or bearing material. Ask hillairgun to make you a seal if you can't buy.

Its solved for some reason from the black yong heng filter the screw in does not seal with the delrin il just use the washer, its probably not meant for the delrin I guess I was just wondering why it wasnt working with the delrin I see where it suppose to have contect with the delrin its a little different than the other m10 fill whips I got it tapers a bit an is not as wide in diameter so that could be the cause.

 

[DpMarks24]

Sounds like it.

 

[steve-l]

Teflon is what should be used.

 

[charlie99]

I had that happen to me also. It was on the pressure gauge as I replaced the original with a larger and different size. The issue was that just one of those derlin washers was not enough to get the right pressure to prevent leaking. I doubled the washer and has not leaked since. I also added teflon tape to the threads prior to reassembly.

 

[orangeokie]

Try using two seals, one on top of the other

 

[rcs9250]

Is it possible you are mixing a female BSPP (straight thread) with a 1/8-27 NPT (tapered thread) ?
Try screwing the two together without the delrin seal and observe if it bottoms out. It’s possible, if the male is a tapered thread it is stopping because the taper is preventing it from going deeper. mixing those threads is a no no. No doubt many have done it and it’s holding but just isn’t designed for mixing different thread systems.

 

[Geezerhood]

Teflon is what should be used.

I agree with steve-I. As long as you are able to compress it, a Teflon washer will probably work better than Delrin or Nylon. Just don't over tighten it. The Teflon washers don't need anywhere near the compression required on the harder Delrin / Nylon washers for a tight seal. On my two Yong Heng filters I use Dowty washers like what you are showing in the photo with the writing "works" on it, and they hold 250 BAR pressure for weeks. Is there some reason you don't want to use a Dowty washer?

 

[steve-l]

Delrin or other nylon derivatives are too soft and often creep losing the seal and often plug the gas passage as well. I will mention this again because some don't listen well. Please identify the thread you are dealing with. It is a safety issue. All British threads use a 55 degree included angle. All straight threads use a gasket to seal at either the top or bottom of the thread. All tapered threads seal on the thread and use a sealant or Teflon tape. Don't mix them up.

 

[rcs9250]

Delrin or other nylon derivatives are too soft and often creep losing the seal and often plug the gas passage as well. I will mention this again because some don't listen well. Please identify the thread you are dealing with. It is a safety issue. All British threads use a 55 degree included angle. All straight threads use a gasket to seal at either the top or bottom of the thread. All tapered threads seal on the thread and use a sealant or Teflon tape. Don't mix them up.

Agreed. Part of the problem is some folks aren’t aware of the different threads in the world. SAE, NPT, NPS, ISO, BSPP, BSPS, MM. I realize some of those are duplicates with just a different designation, the point is, there’s a difference. And there are others as well.
Unfortunately, the 1/8-27 NPT and the British BSPT and BSPP often get assembled together. They’ll go together but definitely aren’t designed to go together.
And no disrespect to those folks that don’t know that. I worked in that industry and was taught/learned the difference.
As steve-l mentioned, the British threads (BSPP and BSPT) are 55° threads and NPT and NPS are 60°. See photo below to see what 60° is referring to. For British the thread angle is 55° instead of 60°. They are not meant to mesh together. There is a definite loss of holding strength. But many do it and it does seem to work. But it can be like driving drunk, every time you start the car you’re one trip closer to disaster.