Prop inspection tube

[fisherman]

Anyone got one? I have often considered it, but never really needed it. Halyard supply GRP tube which is very robust and supplied with an abraded surface for laminating: I would think in many cases it would be simple to install a tube from above the prop to the cockpit floor, or somewhere above the waterline. My idea would be for a screw down deck fitting lid on it, with possibly a fitting inside to hold the cutout piece of hull in place at the bottom to keep the hull fair. Could get you out of a lot of trouble.
Not so easy in a wood boat.

 

[rogerthebodger]

Canal Narrow boats have that exact arrangement and I fitted a GRP square tube to above the waterline on my marine ply boat 35 years age when I was in the UK.

Worked great to clear weed from the prop. Don't know how it affected the prop efficiency.

 

[machurley22]

Still possible in wood

 

[Bilgediver]

Anyone got one? I have often considered it, but never really needed it. Halyard supply GRP tube which is very robust and supplied with an abraded surface for laminating: I would think in many cases it would be simple to install a tube from above the prop to the cockpit floor, or somewhere above the waterline. My idea would be for a screw down deck fitting lid on it, with possibly a fitting inside to hold the cutout piece of hull in place at the bottom to keep the hull fair. Could get you out of a lot of trouble.
Not so easy in a wood boat.

I carry 4 FT Length of pvc drain pipe with a disc of perspex glued in the end. Been used to inspect the props on many boats in the marina.

 

[Barry Jones]

What vessel ? HMS Warrior ?

Still possible in wood

 

[machurley22]

RRS Discovery in Dundee.

http://www.rrsdiscovery.com/index.php?pageID=54

 

[Quidi Vidi]

I carry 4 FT Length of pvc drain pipe with a disc of perspex glued in the end. Been used to inspect the props on many boats in the marina.

You mean something like this?

 

[Bilgediver]

You mean something like this?

Yep....Mine is 26 years old.

 

[Lakesailor]

See the arrow? It's pointing at a prop inspection tube on a wooden steamboat.

However.......on a steam boat if the prop grinds to a halt with a jam-up, it is essential to disengage drive and ensure that no pent-up energy is left in the drive train.
My friend forgot and as soon as he cleared the jam the prop set off rotating again.

Ouch!

 

[nimbusgb]

underwater video camera on a pole - One less hole in the hull.

 

[nedmin]

Most Dutch steel boats have "Weed Hatches". There a good Idea I once cut and pulled a complete keep net through it.Saved a lift out. One of the probs. is that you need a light to drop down as if the water is cloudy you cant see. I have a 12volt 10 watt halogen I lower down taped to a piece of wood.Doesnt matter about it being a waterproof fitting as at 12volt it wont short out.DONT use this on 240v ! If you fit one the top edge needs to be 2to3 inches above water level.

 

[fisherman]

You mean something like this?

That's what we call a water glass. Along with a claw, sort of rope operated grabber on a pole, used to extract valuable trifles off wrecks.

 

[nigelmercier]

underwater video camera on a pole - One less hole in the hull.

I bought a cheap web cam and put it in a sealed plastic box.

 

[AIDY]

maplins sell cheap under water cctv camera's

 

[john_morris_uk]

Most people seem to have missed the point of the OP's post. With a through hull inspection tube that finishes above the waterline, you can not only inspect the propellor but get your arm (or a knife on a pole etc) through the hull from the inside to clear the propellor. Lifeboats have them (or at least they used to).

All good points about underwater cameras and glass ended tubes, but a through hull inspection hatch with a tube ending above the waterline means that you can sort the prop out at sea, in almost any sort of weather conditions, in the dark etc etc. You might ship a fair bit of water up the tube in rough weather, but nothing you can't manage. I don't know why more boats don't have the things. Properly engineered, then there shouldn't be any concern about hull integrity. (Despite some people's paranoia about through hull holes!)

 

[DavidMcMullan]

My father made one on a 33ft fishing boat, with slightly tapered sides from memory. He made a solid plug to go in the tube, so it was fair on the underwater side. I don't recall him having any problems with it.

 

[fisherman]

Most people seem to have missed the point of the OP's post. With a through hull inspection tube that finishes above the waterline, you can not only inspect the propellor but get your arm (or a knife on a pole etc) through the hull from the inside to clear the propellor. Lifeboats have them (or at least they used to).

All good points about underwater cameras and glass ended tubes, but a through hull inspection hatch with a tube ending above the waterline means that you can sort the prop out at sea, in almost any sort of weather conditions, in the dark etc etc. You might ship a fair bit of water up the tube in rough weather, but nothing you can't manage. I don't know why more boats don't have the things. Properly engineered, then there shouldn't be any concern about hull integrity. (Despite some people's paranoia about through hull holes!)

Thank you sir, I was almost giving up.

 

[nimbusgb]

My prop is directly below the fuel tank so no chance of an inspection tube so back to a video camera for me