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Setting end float on the core valve

Started by blueboy, January 14, 2023, 09:00:08 AM

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blueboy

Hi you read all about adjusting the Reg pressure on the Theoben Reg.
There should be approximately 0.5 to 1 mm end float on the face of the core valve to the seat on the pin disc.
Let's say for arguments sake you have 1.5 mm of travel how can you reduce the travel.
It's fine if you are replacing the seals with all the original components, I understand the pin disc once seated on the oring no longer gives you any leeway, and you can only screw in the brass shoulder so far.
Be interesting to hear your thoughts on this cheers.

angrybear

#1
You need to seat the bottle pin disc first, with the valve core removed, then screw in the core until it "seats" & back it off to give the clearance.

If the reg core is in bits, it's easy because you can feel the play on the shaft as you screw the knurled shoulder on to the spacer O ring (BS149 irrc) once the shaft play is set, mark the shoulder & the reg body/bottle adaptor, unscrew the shoulder counting the turns, rebuild the core & screw it back counting the turns back to where it was, then use a reg tester to set the pressure.

If the reg is already set, remove the spacer O ring (BS149), you should now be able to screw in the core by hand until you just feel it seat, back it out half a turn, mark the alignment on both the shoulder & the reg body/bottle adaptor, remove the core counting the turns at the 2 marks, refit the spacer O ring & screw in the core to the same place, check the pressure on a reg tester

Tipex alignment mark using the vent hole to align.

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blueboy

Hi Many thanks for your reply, They are good regs once set up.

Would love to see someone build one with a spring instead of the Bellville washers, would be an even better reg then, you may surprise me and say someone already does.

Once again Thank you.

KevG

belleviles are much better than springs
kevG
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Regards KevG.
Administrator

Squinty

Quote from: blueboy on January 14, 2023, 09:00:08 AM
Hi you read all about adjusting the Reg pressure on the Theoben Reg.
There should be approximately 0.5 to 1 mm end float on the face of the core valve to the seat on the pin disc.

Let's say for arguments sake you have 1.5 mm of travel how can you reduce the travel.

I understand the pin disc once seated on the oring no longer gives you any leeway, and you can only screw in the brass shoulder so far.


If you were to still have 1.5mm of end float after fully tightening down the collar either the pin-disc is coming up short or the core has been refaced a tad too much.
If it's this one... ? Well buggered.
https://rapidforum.co.uk/forum/index.php?topic=2932.msg18048#msg18048



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