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[Ramon]

Hi there,
I'm intending to make a gas regulator in the coming weeks to the Malcolm Beak design. I just wondered if anyone has made one and what material is best to use for the diaphragm. I was considering a piece cut from one of those heavier duty household rubber gloves. Would that be suitable?


Confirmation of this approach or any help anyone might be able to shed on what else to use would be much appreciated.


Regards - Ramon

[derekwarner]

Ramon......

I have a Anton V71 Gas regulator, the spare or replacement diaphragm as supplied is 13 diameter x 0.7 thick Nitrile [NBR].....[not natural rubber according to JMC]

As we know Nitrile is comfortable with temperatures to say 90 degrees C, however certainly a longer life expectancy could be attained by reducing this temperature

So from this I have taken the water pilot signal source from the bottom of the boiler at ~~~~~just under 100 degrees C, and this cools to approx. 70 degrees C at the regulator as opposed to taking the pilot as steam from the top of the boiler at ~~120+ degrees C

We have read of members stamping out such diaphragm's from bicycle tyre tubes ..........or bicycle puncture repair kits 

I have also installed an isolation valve in the water pilot line just before the regulator so I can bleed the line, then commission & test the plant with the gas regulator in line but non functional............

Will this regulator be intended for the beautiful Wide-a-Wake vessel & engine build on the other WEB thread?...........Derek

[Ramon]

Hi Derek,
Thanks for your help. Yes it is for the Wide a Wake but I believe what you are describing is an 'attenuator ?' - I won't be doing this - just a straight forward regulator between gas tank and burner. I have no previous experience of using one but understand it helps to keep the gas pressure constant as the temp varies in the gas tank. Sandy sent me the drawing of both but I only intend to do the regulator at this stage. I will try to find some nitrile sheet though if anyone knows of anything else suitable it would be appreciated.

[/size]I suppose it may seem strange that the Wide a Wake has not been referred to on here so if I may - the reason is simple and can be summed up in one word - 'Time' - there simply isn't enough in the day. For those who might be interested however the build is covered on the Model Engine Maker forum here http://www.modelenginemaker.com/index.php?topic=2851.0[size=78%] I haven't enjoyed myself so much making a model as WaW - the hull nears completion but the engine is destined for a rebuild however hopefully it will be launched this year.


Thanks again Derek


regards Ramon

[Ramon]

Hi again - I now have some nitrile sheet on the way - couldn't find any at .7mm so bought some at .5 and 1mm thick. Now I just have to get the tire valve 


Thanks again - Ramon

[mrsgoggins]

I've made a couple to Malcom' design, one with 1.5mm neoprene and the other with 1mm nitrile. Both worked well after some fiddling.

[hammer]

I have had success with children's balloons, meant for hydrogen. 

[derekwarner]

Goodness hammer........are you planning to bring back the Zeppelin  ......in OZ for kids parties we use bottled nitrogen.....Derek

[mrsgoggins]

That'll be because our balloons have to go up, whereas yours just have to go down - relatively speaking

[derekwarner]

Ramon.......I knew there was an article on Malcolm Beak + Gas regulator.........so GOOGLE confirms = ...there is an older thread here on MBM about Malcolm's gas regulator/attenuator systems.......you may find the article interesting.....Derek

http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CDEQFjAB&url=http%3A%2F%2Fwww.modelboatmayhem.co.uk%2Fforum%2Findex.php%3Ftopic%3D38666.0&ei=T3YSVYbyNuLPmwX514LICg&usg=AFQjCNHPKy8YDnNn0jEbVDEGvpVLm0oABg&bvm=bv.89184060,d.dGY

[hammer]

Yes Derek a senior moment, again.

[Ramon]

Thanks Derek - that makes for encouraging reading    Though I hadn't thought about making an attenuator it sounds like they work very well - possibly thought for a bit later. I confess this is very much an ME 'project' for me- whilst I will sail it I don't see that happening very often - still very much focussed on sailing yachts    (though of course that may change once it's on the water)


Regards - Ramon