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    New Funnel for Fine Offset

    For discussion of DIY weather equipment - sensors, accessories, improvements to existing kit etc
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    Richard Horton
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    Weather Station: Fine Offset
    Operating System: Windows 8.1
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    New Funnel for Fine Offset

    Post by Richard Horton » Fri 10 Jan 2014 2:13 pm

    After my last funnel gave up the ghost, I thought an engineering solution might be the answer, and as a picture paints a thousand word....
    1RH_0272(1).jpg
    1RH_0275 (2).jpg
    1RH_0277 (1).jpg
    Hopefully the material will be UV stable.... or the next plan is to make one out of aluminium, or perhaps do away with the original collector all together
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    Richard

    If it ain't broke, you're not trying hard enough.

    www.martin-weather.co.uk

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    mcrossley
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    Weather Station: Davis VP2
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    Re: New Funnel for Fine Offset

    Post by mcrossley » Fri 10 Jan 2014 3:12 pm

    Delrin? That's a sizeable chunk of whatever it is anyway!

    Richard Horton
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    Joined: Sun 05 Jan 2014 2:10 pm
    Weather Station: Fine Offset
    Operating System: Windows 8.1
    Location: Woodhall Spa, Lincolnshire
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    Re: New Funnel for Fine Offset

    Post by Richard Horton » Fri 10 Jan 2014 3:49 pm

    mcrossley wrote:Delrin? That's a sizeable chunk of whatever it is anyway!
    Acetyl Co-polymer and yes quite a chunk, next issue will be how to mount it, oh and try and remember how to work the fudge factor out.
    Richard

    If it ain't broke, you're not trying hard enough.

    www.martin-weather.co.uk

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    mcrossley
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    Re: New Funnel for Fine Offset

    Post by mcrossley » Fri 10 Jan 2014 4:09 pm

    Richard Horton wrote:Acetyl Co-polymer and yes quite a chunk, next issue will be how to mount it, oh and try and remember how to work the fudge factor out.
    I had to look up the difference. Did/could you not turn it to a diameter that came out as a nice round conversion factor? Second thoughts, that relies on the accuracy of the original FO part.

    What I may do (if I had the time/skills/tools) is calibrate it as-is, work out what the diameter should be for a nice round conversion factor, and turn the rim down to that size.
    Last edited by mcrossley on Thu 20 Feb 2014 9:48 pm, edited 1 time in total.

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    mmcp42
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    Weather Station: own build
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    Location: Leighton Buzzard

    Re: New Funnel for Fine Offset

    Post by mmcp42 » Thu 20 Feb 2014 9:42 pm

    do you intend to polish the inside?
    I wonder if the non-smooth surface would impede the flow of water significantly?
    weather station here: http://www.mmcpix.com/wx.html

    hills
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    Re: New Funnel for Fine Offset

    Post by hills » Thu 20 Feb 2014 9:57 pm

    mmcp42 wrote:do you intend to polish the inside?
    I wonder if the non-smooth surface would impede the flow of water significantly?
    I was just about to say the same thing. I use a standard funnel about the same size and I've polished the inside with marine fibreglass polish to encourage the water to flow straight into the sensor. It really does make a difference as about ".3mm" used to stick to the sides.

    I found it best to work out roughly how much bigger it is to the original and then use that, but then calibrate it with a good quality manual rain gauge mounted nearby. I went from .32 to .36 before it matched exactly. Also bear in mind, from memory, the calibration will affect all rain values collected so far.

    Also would it be possible to make the rebate at the bottom large enough to completely sit over the original. That way I think it would be much more stable.

    Great work!! :clap:

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