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       #Post#: 7374--------------------------------------------------
       steel axel spec
       By: Tinworm Date: August 13, 2022, 4:06 am
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       for a front axle, can I use ERW instead of seamless mechanical
       tube? I know it is less strong (though how much so, I do not
       know)
       Is the extend to which it is less strong very important for us
       in the way we are using the tube?
       One additional factor is that the Bedelia has central sliding
       pillar suspension, so all the action will be at the centre of
       the length rather than distributed.
       #Post#: 7382--------------------------------------------------
       Re: steel axel spec
       By: jim Date: August 14, 2022, 1:13 am
       ---------------------------------------------------------
       Hi Peter, If I was making your axle I would use 40mm o/d cds
       tube with a 2 to 2.5mm wall. Welded seam tube of a similar size
       should be strong enough but it will bend easier.
       #Post#: 7387--------------------------------------------------
       Re: steel axel spec
       By: RhysN Date: August 14, 2022, 2:23 am
       ---------------------------------------------------------
       FWIW the axle on Tim Gunn's Grafton is 25 x 2.5 mm tube ERW.
       Tested by time. He does however have 2 springs so less of a
       point load. f you wanted to go as small as that you could make a
       diamond shaped spreader plate to help distribute the loads.
       #Post#: 7388--------------------------------------------------
       Re: steel axel spec
       By: Tinworm Date: August 14, 2022, 4:09 am
       ---------------------------------------------------------
       [quote author=jim link=topic=950.msg7382#msg7382
       date=1660457608]
       Hi Peter, If I was making your axle I would use 40mm o/d cds
       tube with a 2 to 2.5mm wall. Welded seam tube of a similar size
       should be strong enough but it will bend easier.
       [/quote]
       Thanks very much, Jim.
       #Post#: 7389--------------------------------------------------
       Re: steel axel spec
       By: Tinworm Date: August 14, 2022, 4:13 am
       ---------------------------------------------------------
       [quote author=RhysN link=topic=950.msg7387#msg7387
       date=1660461821]
       FWIW the axle on Tim Gunn's Grafton is 25 x 2.5 mm tube ERW.
       Tested by time. He does however have 2 springs so less of a
       point load. f you wanted to go as small as that you could make a
       diamond shaped spreader plate to help distribute the loads.
       [/quote]
       Yes, I think you are right, point load is the issue with mine.
       The Bédélia has a support structure, but I am not sure mine will
       add much strength, so need to think about having it strong
       enough on its own
       [img][/img]
       #Post#: 7390--------------------------------------------------
       Re: steel axel spec
       By: Tinworm Date: August 14, 2022, 4:21 am
       ---------------------------------------------------------
       [quote author=jim link=topic=950.msg7382#msg7382
       date=1660457608]
       use 40mm o/d cds tube with a 2 to 2.5mm wall.
       [/quote]
       I was hoping to use 34.9mm x 2mm (converting from the imperial
       measures normally quoted 1 3/8th x 14swg). Do you think the 40
       is significantly better? Aesthetically, the smaller tube might
       look better, but not if it is bent at the side of the road.
       #Post#: 7391--------------------------------------------------
       Re: steel axel spec
       By: Tinworm Date: August 14, 2022, 4:51 am
       ---------------------------------------------------------
       [quote author=jim link=topic=950.msg7382#msg7382
       date=1660457608]
       Hi Peter, If I was making your axle I would use 40mm o/d cds
       tube with a 2 to 2.5mm wall. Welded seam tube of a similar size
       should be strong enough but it will bend easier.
       [/quote]
       on the strength of your recommendation, I have just ordered a
       length. Thanks very much
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