Advice on These Thru Hulls From Raymarine

[fxykty]

Originally Posted by Madehn

I am thinking that the wind instruments use input from the paddle wheel when figuring true and apparent wind speeds. Am I mistaken in this? If not you maybe absolutely correct that the whole paddle speed sensor thing is a dinosaur.

That’s a whole other discussion RE: true wind vs ground wind. Your chart plotter will probably have a setting for which speed input you want it to use to calculate true wind - STW or SOG. If you don’t really care about precision sailing then using SOG is perfectly fine. One less thing to calibrate and clean, and no nylon fitting below the waterline.

[stormalong]

Originally Posted by MicHughV

Since the advent of GPS, chartplotters, etc. the use of a speed sensor is somewhat moot.

Most hull speed sensors come with a "plug" in the even the sensor is removed.

Were it me, and this is my modi operandi....I just leave the plug in and fugetabout the speed sensor. In the past, I have tired of diving aboard to clean that little paddle wheel.

With the advent of GPS, I see little use for it.....but that's just me.

Originally Posted by Madehn

I am thinking that the wind instruments use input from the paddle wheel when figuring true and apparent wind speeds. Am I mistaken in this? If not you maybe absolutely correct that the whole paddle speed sensor thing is a dinosaur.

I do do not want to hijack this thread. However, I cruise in Puget Sound where tidal currents are significant. Speed through water vs. SOG is important.

[MicHughV]

I can't say for sure, that the thru' hull paddle wheel influences the apparent wind one way or another.
I'm not sure how that would work, if at all.

Only with the boat at rest does the wind indicator indicate true wind speed and direction, and off course, any hull paddle wheel, would be silent at that moment in time.

Once you are moving, wind speed as indicated by the wind paddle sensor would be apparent wind speed. I think this would hold true for the entire 360 compass range.
Wind direction, except for dead down wind/upwind would also be apparent, while the boat is moving.

Again, one would think the GPS would calculate forward speed, which could be used to to provide some real/apparent wind direction.

But...I'm not sure. Maybe smarter brains than me can provide a better answer.

I know that I keep the plug in. I could keep the paddle wheel in too, but the plug doesn't catch any weeds, debris, etc.

It's an interesting topic though. I tend to sail " by the seat of my pants" and don't rely too heavily on modern electronics.

I often come across sailors, whose eyes are glued to that tiny screen, instead of taking in what is going on around them.

[HeywoodJ]

Originally Posted by Madehn

After reading some of the replies, i thought perhaps i was being a bit paranoid and did some more research-- what i found at practical sailor tells me that my instinct that these nylon thru hulls are NOT a good idea for this type of below water line sensor. I have since gone back and ordered new thru hulls (bronze) made for the RayMarine i50/i60 setup. Here is the article from practical sailor:
https://www.practical-sailor.com/sys...h-hull-warning

No disrespect for those that feel they are strong enough-- your boat your choice but i think i am going to go with practical sailors advice and my gut.

Originally Posted by Madehn

....but the vendor specifically said that the thru hulls supplied with the Raymarine package were nylon-- s...

What makes you think the vendor is right? Airmar specifically says that their plastic through hull fittings are ABYC H-27 compliant, they stamp it right on the unit:



And ABYC H-27 compliance requires UL testing. Which in turn means they are not straight nylon (because straight nylon can't pass the tests). So, all the requirements of the article you linked (which is the single opinion of one person that got published in PS, not a PS research article with something other than hearsay to back it up) are met by the 'nylon' through hull fitting you received. If what you received is not stamped as ABYC H-27 compliant then I would be having words with your vendor - it is likely not the genuine product.

[Searles]

The fittings referred to in practical sailor ,has nothing to do with the types of fittings supplied by ray marine ,but your boat your money .⛵️⚓️

[wyb2]

Originally Posted by Madehn

After reading some of the replies, i thought perhaps i was being a bit paranoid and did some more research-- what i found at practical sailor tells me that my instinct that these nylon thru hulls are NOT a good idea for this type of below water line sensor. I have since gone back and ordered new thru hulls (bronze) made for the RayMarine i50/i60 setup. Here is the article from practical sailor:
https://www.practical-sailor.com/sys...h-hull-warning

No disrespect for those that feel they are strong enough-- your boat your choice but i think i am going to go with practical sailors advice and my gut.

Not saying you are wrong, I’m sure bronze will work great, but that article lost me in literally the first four words.

“Cracked nylon (acetal plastic) thru-hulls are a common problem….”

Acetal and nylon are different plastics. They author failed to google the words he was using.

https://en.m.wikipedia.org/wiki/Polyoxymethylene

https://en.m.wikipedia.org/wiki/Nylon

Also, I’m pretty sure Marelon is just a glass filled nylon with UV stabilizers added (kind of like our boats are glass reinforced polyester) but I don’t have a link for that one.

[goboatingnow]

Way too much overthinking here.

I have plastic Ray tru hulls since the boat was built in 2004. Perfect

[spaman]

I replaced mine with the same Raymarine units last year. I have no issue with the plastic through hulls. The previous plastic through hulls were 21 years old and it was time to replace together with the rest of the through hulls (although plastic showing no sign of failing).
My critique of the units themselves is that the depth transducer doesn't have a dummy/flap and is fixed. This necessitates a few dives to clear any growth despite using transducer paint. The non-return flap on the speed unit is pretty crap and you can expect a couple of litres of water coming in even if you're quick doing the switch with the dummy. The speed readout is not accurate compared to SOG, but the best I have been able to adjust it to has been to 0.2-0.4 knots less.

[Trawlerman]

As I have previously commented in other topics, I really wonder why anyone in this day and age would want a water-speed sensor. GPS is so accurate these days and has the advantage of true speed-made-good over distance, which for planning time-to-go to destination is a must have. On the inland rivers that I boat on a lot, you could quite easily be reading a speed of 4 knots water speed and in fact be backing up! I too am a bit paranoid about having any holes in the hull that I don't strictly need, and on solid fiberglass hulls like my 50' Marine Trader the shoot-through-the-glass transducers do a fine job for depth.

[RedneckRedcoat]

Your over thinking this

[smacksman]

As said above, shoot-through-the-glass transducers do a fine job for depth.

Speed through the water on my old boat without electricity was obtained by maths to within half a knot.
Know a measured length on deck to the stern - in my case 8m from hounds to stern. Drop a fishing float in at the hounds and time it to the stern.
1 knot = 1 nautical mile / hour = 1852m / 3600 seconds = 1m / 2 seconds
A hand held gps and an estimate from the tide tables was even better!

[stormalong]

Originally Posted by smacksman

As said above, shoot-through-the-glass transducers do a fine job for depth.

Speed through the water on my old boat without electricity was obtained by maths to within half a knot.
Know a measured length on deck to the stern - in my case 8m from hounds to stern. Drop a fishing float in at the hounds and time it to the stern.
1 knot = 1 nautical mile / hour = 1852m / 3600 seconds = 1m / 2 seconds
A hand held gps and an estimate from the tide tables was even better!

Great! Trim the boat, drop a float, time the float, do the math, trim the boat drop a float, time the float, do the math, trim the boat, drop a float, time the float, do the math. Day and night.

As opposed to trim the boat, glance at a knotmeter.

Get real.

[RedneckRedcoat]

Originally Posted by smacksman

As said above, shoot-through-the-glass transducers do a fine job for depth.

Speed through the water on my old boat without electricity was obtained by maths to within half a knot.
Know a measured length on deck to the stern - in my case 8m from hounds to stern. Drop a fishing float in at the hounds and time it to the stern.
1 knot = 1 nautical mile / hour = 1852m / 3600 seconds = 1m / 2 seconds
A hand held gps and an estimate from the tide tables was even better!

Are you still manually sounding depth with a plumb line and carry a plank for walking on too lol

[smacksman]

Originally Posted by RedneckRedcoat

Are you still manually sounding depth with a plumb line and carry a plank for walking on too lol

Haha! Yes - without electricity on board. Still I expect if you lost all power it would be 'Mayday'. With a bit of experience it is amazing how close you can get judging the speed by looking over the side.

[RedneckRedcoat]

Originally Posted by smacksman

Haha! Yes - without electricity on board. Still I expect if you lost all power it would be 'Mayday'. With a bit of experience it is amazing how close you can get judging the speed by looking over the side.

I couldn’t resist with that one . Figuring out where your at with a compass and a map is something everyone should learn. I personally would only call mayday if our boat was actually sinking.