Sir Yrvind ....Consider that you do NOT need a full span axle for this use. Then all you have to do is create a U fittling to support a small axle shaft each side of the the boat. Ue a larger plate to fit the U fitting to the hull on each side. Then, no need for any axle at all. As there will be no appreciable bending the 8mm is probably very well suited. :)
Sizing axles for transportation must consider dynamic loading. In your case, this wouldn't be driven by forward speed, but more likely by the ratio of the (hard) wheel diameter to the defects in the "road" surface. A quick insight (in my opinion) would be to consider the standard axle diameters of automobiles or trailers with approximately the same gross weight. This will likely point to an axle of approximately 2cm diameter in silicon bronze. This will also likely meet your usual desire for robustness.
Good job. Never heard of an Amphibious Sailboat.... lol Leave it to Sven to design and build one. You never stop trying to improve something. Amazing!!!
Or Yrvind, insert a bronze tube into each bilge keel as a stub axle so the bilge keel acts as the support for the 8mm shaft and wheel each side (independently)
There are many things to consider here, it's not just the diameter of the axle, you need to know the distance between the wheel and the hull (the larger this distance the thicker the axle needs to be), but also the width of the wheel and if the axle will be supported on both sides of the wheel or only 1 side (e.g. a bicycle fork supports both sides of the axle, but a car only supports 1 side) Also for reference you're Mum's car you showed in an earlier video (SAAB 96?) weighted under 1 tonne (about 950kg) so that would give you some idea, 4 wheels with the axles only supported on 1 side for a similar weight. I'm not a mechanical engineer but do have an engineering background, but I've been working in IT for over 30 years so am not qualified to do the calculations, hopefully this comment is helpful thought. As someone else mentioned, draw what you're thinking to build and it'll be easier to work out the diameter you need, or to give you suggestions on how you can achieve the same result with a more affordable materials.
It looks like you found the elastic limit on the axle with that weight. I think bigger is better because you have to remember that the force added from hitting the ramp could bend it. It also depends on where you mount the wheel. If the bearing is close to the wheel then there will be less bending force on the shaft.
I don't know how to calculate this, but have experimented with various stuff plenty. Its a pretty though load on those wheels, particularly in situation where only one touch the ground. Not sure what material you will use for the axle, probably something less prone for corrosion, but i would play it safe and do it 25-30mm. Small wheels and that weight, it will not be easy to move your boat with hand, fully loaded in any kind of sloop, soft or even slightly uneven ground. My RIB boat on the trailer is 1 Ton, on even flat ist ok to move, but not on anything else(15 inch wheels on it).
Hej Sven alltid intressant att följa ditt båtbygge , och din noggrannhet och dina tester för att uppnå rätt hållfasthet i din båt . Snart är du iväg ut på havet igen önskar dig lycka till och ett Gott nytt år 🙂👏⛵⛵
Wouldn't it be easier to just find a trailer, pipes, logs, or something on site as and when you need it? Would the masts be strong enough to use as rollers if necessary? Carrying a winch might be handy if you need to pull up a slope. Surely chances are that wherever you go someone will help you ; you're well known and have lots of friends all over the world. Having said that, I've never seen you take any of your boats out of the water during the voyages.
Sir Yrvind ....Consider that you do NOT need a full span axle for this use. Then all you have to do is create a U fittling to support a small axle shaft each side of the the boat. Ue a larger plate to fit the U fitting to the hull on each side. Then, no need for any axle at all. As there will be no appreciable bending the 8mm is probably very well suited. :)
Sizing axles for transportation must consider dynamic loading. In your case, this wouldn't be driven by forward speed, but more likely by the ratio of the (hard) wheel diameter to the defects in the "road" surface. A quick insight (in my opinion) would be to consider the standard axle diameters of automobiles or trailers with approximately the same gross weight. This will likely point to an axle of approximately 2cm diameter in silicon bronze. This will also likely meet your usual desire for robustness.
Good job. Never heard of an Amphibious Sailboat.... lol Leave it to Sven to design and build one. You never stop trying to improve something. Amazing!!!
You're the first person I've seen with the same mindset I have towards sailing. I am so ready. Thank you for being you.
I dont understand your math, but I understand your work!❤❤
Or Yrvind, insert a bronze tube into each bilge keel as a stub axle so the bilge keel acts as the support for the 8mm shaft and wheel each side (independently)
There are many things to consider here, it's not just the diameter of the axle, you need to know the distance between the wheel and the hull (the larger this distance the thicker the axle needs to be), but also the width of the wheel and if the axle will be supported on both sides of the wheel or only 1 side (e.g. a bicycle fork supports both sides of the axle, but a car only supports 1 side)
Also for reference you're Mum's car you showed in an earlier video (SAAB 96?) weighted under 1 tonne (about 950kg) so that would give you some idea, 4 wheels with the axles only supported on 1 side for a similar weight.
I'm not a mechanical engineer but do have an engineering background, but I've been working in IT for over 30 years so am not qualified to do the calculations, hopefully this comment is helpful thought.
As someone else mentioned, draw what you're thinking to build and it'll be easier to work out the diameter you need, or to give you suggestions on how you can achieve the same result with a more affordable materials.
It looks like you found the elastic limit on the axle with that weight. I think bigger is better because you have to remember that the force added from hitting the ramp could bend it. It also depends on where you mount the wheel. If the bearing is close to the wheel then there will be less bending force on the shaft.
I don't know how to calculate this, but have experimented with various stuff plenty. Its a pretty though load on those wheels, particularly in situation where only one touch the ground. Not sure what material you will use for the axle, probably something less prone for corrosion, but i would play it safe and do it 25-30mm. Small wheels and that weight, it will not be easy to move your boat with hand, fully loaded in any kind of sloop, soft or even slightly uneven ground. My RIB boat on the trailer is 1 Ton, on even flat ist ok to move, but not on anything else(15 inch wheels on it).
Hej Sven alltid intressant att följa ditt båtbygge , och din noggrannhet och dina tester för att uppnå rätt hållfasthet i din båt . Snart är du iväg ut på havet igen önskar dig lycka till och ett Gott nytt år 🙂👏⛵⛵
Wouldn't it be easier to just find a trailer, pipes, logs, or something on site as and when you need it?
Would the masts be strong enough to use as rollers if necessary?
Carrying a winch might be handy if you need to pull up a slope.
Surely chances are that wherever you go someone will help you ; you're well known and have lots of friends all over the world.
Having said that, I've never seen you take any of your boats out of the water during the voyages.
these wheels will be more prectical.
You have not seen me doing it before. OK, but I like to do new things.
Looks like a giant skateboard wheels 🛞 skateboard 🛹 axles coated in zinc?
Wouldn't wheels add a huge amount of drag in the water or does he take them off once they are in the water?
Hi friend, i have difficulty with paypal want to send you small contribution but trying to amd failing…
Add a drawing so we know what we're calculating...
Good idea
Never going to sea again.
i am sorry for you