Welding/cutting torch packing seals.

[Highpower]

(09-07-2019, 07:59 AM)rleete Wrote: The Teflon that McMaster sells is quite hard.  I have some, and while it machines fairly well, it's not soft, like Delrin.

I would think that you would want something softer for the packing, to kind of "squish" around the stem as you tighten the packing nut.

You must have a different flavor of Teflon. Delrin hardness (McMaster): Rockwell R120-R122 (Hard)
1/2" PTFE rod (McMaster): Durometer 50D-65D (Medium Soft)

The real fly in the ointment though is that Delrin is flammable and is non-self extinguishing. It doesn't stop burning until available oxygen is used up or removed. Note in the description - "Must not (be) used for Oxygen service."

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