It's not a big issue Andy, it’s just something I must keep in mind when making props in the future. If you have a look @ the pictures of my prop you will see the position of the blade tip is quite far aft. I was expecting it would give quite a strong rotating moment to the sub, no surprise here.
Probably I will make a few morevariants to see which one works best.
grtz,
Bart
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Nice work. I'm surprised the prop is causing you big issues. The pitch looks a bit on the high side for a single screw, but not excessive. Increasing the weight of the boat can help with torque roll to some extent.
A good pitch to diameter ratio for single screw subs with large multi-blade props is between 0.5-1. Raboesch scimitar props are around 1:1 and they work very well, but as your boat is a wet hull it may benefit from something even lighter in pitch, e.g. 0.8.Leave a comment:
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Thks guy's means a lot.
It's a G&T with submarine Ice cubes
Grtz,
Bart
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Today it was the first time I took command of a sub.
All went well, she sailed and dived…and came up.
As a full time noob I pressed the time-lapse button of my phone recording the dived part, so that’s nice to see….I’m sorry for that.
Observations made:- I had the boat trimmed perfectly. Dived the tower sits 5-10mm out of the water.
- Not a drop of water was ascertained in the SD.
- She turned like the real one…..awful, horrendous.
- At 1/3 of throttle she was sailing realistically (you can see it in the video).
- The fwd dive planes are a little too small (they are on scale) she dives but only at full throw of the stick and I need to help by trimming the rear dive planes to bring her ass up. Once under water she keeps her depth like a pro.
- The pitch of the prop is too high, when I make my next prop I need to bring the pitch back gradually toward the blade tip. The rotating moment of the prop is to big now especially when going ahead from ‘dead in the water’. The speed of the sub does not increase from 50% to full, this is also an indication the pitch is to high, the prop needs to be flatter.
- The magnetic pushrod connectors sometimes disconnect when she sails astern with rudder hard to PS.
Grtz,
Bart
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You are a machine. I'm also stealing your ballast idea - and maybe one of those giraffes - they look cute.Leave a comment:
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Next sunday will be her first dive, so I finish all the internals.
I owned you guy's some pictures of the arm supporting the pushrod
The 2mm setscrew on the prop
The 2mm setscrew on the dive plane, I had to fabricate threaded bushings as the material thickness is so little on this part of the plane.
The ballast that can be altered when needed, the lead is slotted.
the pool were the "poolrun" will take place next sunday
Grtz,
Bart
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They all sell Renshape on indent (8 - 12 wees) and only then in 1500 x 500 sheets which cost as much as a house. No one sells small blocks down here. I've emails Sika Australia to see if they will get some small bits in for a trial. Not hopeful however.Just that one...I don't have long drils of 2mm.
Maybe this helps
Only 4k, 41hr drive
1k, 10hr drive
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Just that one...I don't have long drils of 2mm.
Maybe this helps
Only 4k, 41hr drive
1k, 10hr drive
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You crazy Nimrod. You bored this hole by hand, didn't you?
I can't find Sikablok, Renshape, tooling board, pooling board, **** sandwich or any other useful bloody thing down here. Frustrating. I'm considering an attempt to carve concrete - its about the softest thing that there is around here. Sigh, swear, fart, grumble etc etc...Leave a comment:
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Just painting left and I'm back where I left the path to completion.
Grtz,
Bart
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