furlers

Discussion in 'Sailboats' started by whitepointer23, Mar 19, 2012.

  1. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Ok, if you want to know if the pull in the stay will rip the one disk off the end where you welded it to the 'hollow tube' or not - calculate the length of weld times the material thickness.

    38mm and say only a 1mm thick weld ~ 119mm^2.... as strong as 12mm bolt which is 113mm^2. The one in the pic is 3mm SS, and the weld was thicker than 1mm... so the bolt goes first which is unlikely.

    Take care when welding the disks, they buckle if they get too warm from the weld.
     
  2. michael pierzga
    Joined: Dec 2008
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    Location: spain

    michael pierzga Senior Member

    The issue with roller furling is the thrust bearing.
     
  3. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Hi Michael,

    Correct. However if you stack a bunch of the normal bearings, you can add their lesser side load carry capability, which makes more than a single thrust bearing. They also keep the tube and bolt streight by forming a tube for the bolt.
     
  4. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Sorry that was a 32mm tube with 2mm wand thickness and bearing outside dia is 28mm. I drilled the inside of the tube clean so the bearings would fit. It won't make much difference is the bearings are a loose fit ie you use a 1.5mm tube instead.
     
  5. whitepointer23

    whitepointer23 Previous Member

    nice workmanship fanie, the furler i am looking at is made out of pvc, yours looks a lot better though.
     
  6. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Thanks.

    I won't trust PVC... especially in the sun ! and I have doubts that it will be strong enough.

    It's a matter of drawing the parts, have them laser cut and tig weld them together or someone (who can weld) weld them for you. They should last forever, or close.

    The pest is to find standard tubing and bearings and bolts that work together. Seems the manufacturers doesn't exactly talk to one another about sizing...
     

  7. Fanie
    Joined: Oct 2007
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    Likes: 177, Points: 63, Legacy Rep: 2484
    Location: Colonial "Sick Africa"

    Fanie Fanie

    Most things are really basic if you spend the time to figger it out properly. I made my own cleats from 12mm rod and a few bolts because the off the shelf ones here are bloody expensive. I just got the bolts because they are threaded already although one can buy a die nut and thread them yourself, it's not rocket science.

    There is a box full of spares already, blocks, anchor roller, rod holders, all tested and works great. I even made a rod bender to make u-bolts.
     

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