Disc regulator

I am trying to get a Don Young 5" gauge Hunslet loco steam regulator to seal when closed which I have achieved if I screw the disc to the regulator but when I apply a spring so the disc can rotate the disc lifts when tested on air. I am using a 20 SWG spring as specified in the drawings.

Advice appreciated please.

Tom

Not sure how you are air-testing your regulator & am not familiar with this particular design but don't overlook that conventionally when in service the boiler pressure will be forcing the the two surfaces of the disc regulator together.

If, for example, you are testing by applying air pressure to the the outlet then that pressure differential is the opposite to what will happen in service.

There are a couple of owners of Don Young designed locos over on Model Engineering Clearing House, indeed I think that there are a couple of 'Hunslet owners' amongst them. Maybe worth posing your issue there too?

Regards,

Phil

There was an article in ME a couple of years ago about putting a full bore water or gas valve into a 5 inch Don Young black 5. It seemed to work well. Maybe you could dig that out and try it.

are you supplying the Air Pressure in the opposite direction which the Steam would flow ? In that Case I doubt it would seal with using just the Spring. But that Test indicates nothing regarding the Functionality of the Regulator.

There is an almost identical Thread currently on "Model Engineering Clearing House", i.e. "modeleng.proboards.com". You do not need to log-in to read it. Click on "General Chat" and about 24 Topics down is "Stroudley Regulator Problem". It's worth a read.

I hope this helps.

Use MECH Forum for loco questions, not this one. That’s where loco people post these days.
Also, disc regulators are, in general, a disaster. Search for the use of stainless ball valves for regulators. Recent thread on MECH. now if you want to ask a question about a Myford lathe here, you’ll get seven pages of replies.

MECH have been discussing this subject recently here

Tom,

Have you checked that there is a bit of slop between the operating shaft and the disk? If you make the fit too good, the shaft can tilt the disk off the face. Try a bit of gentle easing with needle files.

Martin

Sorry to put this in here - if the moderators don't like it - please delete it.

I have been trying to register on the MECH site for some weeks now - I followed all the steps carefully, including the Registration Video, many times, but get to the final stage, and it apparently just freezes. I have checked many times, and don't believe I am making any mistakes. As far as I can see after much searching, there is no way to contact the web-manager, or anything else to ask for help.

This thread happened along and mentioned the MECH site, so I wanted to ask if anyone here can offer any suggestions.

Thanks.

Apologies for the delayed reply, day job getting in the way of workshop time.

Thank you to everyone for your replies. The way I am testing the regulator I now realise is wrong and the MECH mention is a great suggestion so I will be checking that out if I cannot get the current regulator to seal in it's current state.