Bubbles

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Bubbles

Postby Mike Brown » 2011 Dec 08, 22:21

As I suggested the section i will start it off. I have a sheathed Minimum thermometer with a serious amount of bubbles in it. I have tried all the usual methods, and dropping on to a book as suggested in the Cumbria Weather forum. Still have bubbles. What is more, the spirit seems to have moved past the indicator so even if I could remove the bubbles then i doubt it would read correctly. Any ideas please to get this beastie back in to operation?

Thanks

Best wishes

Mike
Mike Brown
 
Posts: 49
Joined: 2011 Dec 03, 18:04
Location: Bolton le Sands, North West Lancashire

Re: Bubbles

Postby Darren Rogers » 2011 Dec 09, 08:32

Mike - my method is probably not the best one, but it as worked for me - BUT YOU HAVE TO BE VERY CAREFUL.

also would not use it on a max' thermom'.

Do check the thermom' carefully though for cracks, etc, because if it is broken then definitely do not try my remedy.
Basically it is the warm water version, but needs to be done very gradually. Obviously start the process from room temp.
3/4 boil a kettle and put the water in a shallow dish/tray - You could try holding in mildly warm running tap water to start.

Hold the thermom' in the steam at first - see the reaction in the spirit - will start to go to the right.
As I said, very gradual - lower the thermom', but don't put in the water yet, maybe add some more hot water.
Finally just dip the end in the water and take straight out - repeat process.

Gradual is the process and because you are doing it gradually you will need to add a little warm water occasionally, until the spirit finally is all back in the bulb (needs to go back slowly, not at speed) - I have found that any spirit that has gone past the pin will squeeze back.

I've done it and it has worked for me - I'm sure it isn't in any manual and as they cost £120 ish to buy privately you do need to be careful.
Darren Rogers
Maulds Meaburn
Cumbria (Half way between Shap and Appleby)

http://www.mauldsmeaburnweather.co.uk
Darren Rogers
 
Posts: 145
Joined: 2011 Nov 27, 20:22
Location: Cumbria - half way between Shap and Appleby in the Eden valley

Re: Bubbles

Postby Graham Easterling » 2011 Dec 09, 14:05

> I've done it and it has worked for me - I'm sure it isn't in any manual and as they cost £120 ish to buy privately you do need to be careful.

Just to let you know that they are available at around £80. E.g. http://www.metcheck.co.uk/acatalog/H15_ ... meter.html
With a bit of searching I found my last one for around £70, though metcheck tend to be the cheapest in my experience.

Graham
Penzance
Graham

Penzance Weather Station
Grid Ref:
SW464231 - Post Code: TR18 4TP
19m AMSL - Aspect SSE
In a SE - NW orientated valley

23 Years of Penzance Weather Records : http://penzanceweather.atspace.com/weather.html
Graham Easterling
 
Posts: 316
Joined: 2011 Nov 30, 20:29
Location: Penzance, Cornwall

Re: Bubbles

Postby Darren Rogers » 2011 Dec 09, 17:17

Graham, just went through the Metcheck system to purchase one of these and the final price with p+p and VAT was £94.

To my knowledge that is very much the price you are going to pay with most companies, the other two of note (and respect) are:

Russell Scientific (who I use)
Fairmout weather.

Both V/good and reliable.
Darren Rogers
Maulds Meaburn
Cumbria (Half way between Shap and Appleby)

http://www.mauldsmeaburnweather.co.uk
Darren Rogers
 
Posts: 145
Joined: 2011 Nov 27, 20:22
Location: Cumbria - half way between Shap and Appleby in the Eden valley

Re: Bubbles

Postby Mike Brown » 2011 Dec 11, 17:34

The boiling water worked, thank you!! It was in the end a pan of boiling water and a case of who blinked first, but got all the bubbles out of the way and I think it is now working. As you suggest it is not for the faint hearted though.

Thanks once again

Best wishes

Mike
Mike Brown
 
Posts: 49
Joined: 2011 Dec 03, 18:04
Location: Bolton le Sands, North West Lancashire

Re: Bubbles

Postby Darren Rogers » 2011 Dec 11, 20:17

Mike - i never said boiling water, just 3/4 bolied.

anyway, glad it's sorted and that it worked.

Knowing what your diff' will be between air temp and ground temp' will be interesting to note.

I've now just got a Max' thermom' that i need to sort.
Darren Rogers
Maulds Meaburn
Cumbria (Half way between Shap and Appleby)

http://www.mauldsmeaburnweather.co.uk
Darren Rogers
 
Posts: 145
Joined: 2011 Nov 27, 20:22
Location: Cumbria - half way between Shap and Appleby in the Eden valley

Re: Bubbles

Postby Mike Brown » 2011 Dec 15, 21:45

Thanks Darren, I know that you said not boiling water, but in the end that is the only thing that would shift the bubbles it was that badly bubbled (?). I tried the cooler water approach but it just did not go anywhere, hence the game of chicken. As you say, all is working well now, so I am happy .

Best wishes

Mike
Mike Brown
 
Posts: 49
Joined: 2011 Dec 03, 18:04
Location: Bolton le Sands, North West Lancashire

Re: Bubbles

Postby Mike Brown » 2011 Dec 21, 20:28

Bubbles appeared in my Concrete min thermometer. A little warm water this time did the trick, and I do stress warm water.

Best wishes

Mike
Mike Brown
 
Posts: 49
Joined: 2011 Dec 03, 18:04
Location: Bolton le Sands, North West Lancashire

Re: Bubbles

Postby Steve Flitton » 2012 Jan 27, 19:54

Hello,
I have to report that I have a grass minimum thermometer with a 'sticky' glass index. On a few occasions, maybe half a dozen times a year, the spirit fails to push the index to the minimum and instead pushes past it breaking up the column into bubbles - very annoying. Hopefully I'll purchase a new thermometer in the near future but they are quite expensive. Anyway I've always been able to remove the bubbles using a kettle. Fill the kettle with cold water and hold with the bulb end in. Switch on and as the temperature rises, so will the spirit and the bubbles.It will speed up quite quickly but it will soon reach the small chamber at the top of the thermometer before the water boils. I admit it is a bit scary but it's always worked for me. One little tip, store the thermometer upright until the temperature returns to normal. This will ensure that the spirit settles normally otherwise you may find your readings are slightly out
Steve Flitton
 
Posts: 13
Joined: 2011 Nov 29, 21:30


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