Are Bow Thrusters destroying canal banks?

[Neil TNC]

In answer to Neil Arlidge's comment, watertight comparment or not, it is still a rust trap. Why would someone with your experience want one?

 

I just can't (always*) get the "staff"!

Avast me hearty!...I like the cut of your jib!**....you would have made an excellent TNC slave crew member!

 

As for rust trap, here are a few things to throw into the pot, for you to pick apart, perhaps others can add some more....

 

Bowthruster should be in watertight compartment (done that one)

Bowthruster tube (and locker) should be corrosion protected on the internal (inside hull) surfaces (I have seen a NB with internal tube, partialy coverded with spray foam, over bare metal, tube merrily corroding away from the inside!)

Bowthruster locker should be well ventilated (from the top!), to stop condensation.

The correct grade / thickness of seamless tube should be used (many builders do not, as this is expensive).

The front anodes should be as near as possible to the bowthruster tube.

The bowthruster should be correctly and sufficiently sealed in the first place, so no water seapage adds to internal corrosion.

Bowthruster prop(s) nut(s)should have an anode fitted.

Bowthruster tube / hull join should be properly welded both sides. (I have seen a barge where the tube was only welded on the outside!)

Bowthruster battery should be isolated when boat laid up (I have seen a barge where the bowthruster batteries were not completely isolated from the bowthruster, this caused corrosion damage to the bowthruster / contactor, God know what it was doing to the tube)

Hydraulic bowthrusters will cause less corrosion to tube as no stray currents present, as with electric bowthrusters.

 

always*

TNC CWDF members are OK

 

**

Just getting in practice for Sunday

[Natalie Graham]

 

Bowthruster should be in watertight compartment

 

 

 

Sealed off at both ends of the tube should see that one sorted.

 

 

[luctor et emergo]

Sealed off at both ends of the tube should see that one sorted.

[bargemast]

I do have an hydraulic bowthruster in a special thickwalled tube, I must say that I very rarely use this gadget but am happy to have it, as it has proved handy when comming alongside a moored boat in a strong lee-wind. On my commercial barges I never had one, and still managed to get to where I had to go without doing any damage, but having had one would have made my life much easier. Nowdays it's not easy to find any commercial barge (even as small as a 38m) without one, and I don't understand the fuss about having and using one, as long as it's not used permanently to compensate for the wrong rudder position with quite a few boaters seem to be doing.

 

Peter.

[Proper Job]

ban them i say! they also seem to destroy peoples ability to steer with the tiller, i followed a boat down hatton earlier in the year and they were using the bow thruster to steer into every lock.

I was chewing the cud with Roger at Abingdon lock the other day.

 

A 27' airfix kit came in with twin sterndrives, loads of blipping of the throttle etc, and then to top it all, used a bow thruster to get alongside.

 

Rog' and I looked at each other (once the blue hue from the exhaust had cleared) in disbelief

[Naughty Cal]

I was chewing the cud with Roger at Abingdon lock the other day.

 

A 27' airfix kit came in with twin sterndrives, loads of blipping of the throttle etc, and then to top it all, used a bow thruster to get alongside.

 

Rog' and I looked at each other (once the blue hue from the exhaust had cleared) in disbelief

 

If you want a good laugh hang around in or around Burton Waters on a sunny summer lunch time when all and sundry have come to their boats for their annual outing.

 

You get a lovely corus of bow thrusters, stern thrusters and labouring twin engines as the hopeless captains attempt to launch from their berths surrounded by a curtain of smoke. It is well worth the journey trust me. On days like this we stay firmly attached to our berth with a beer in hand watching the fabulous displays unfold.

 

ETA: For those who have never encountered a twin engined boat be it stern or shaft driven, you dont even need a steering wheel, you can manouvre them with the engines. One in forwards and one in reverse and they pretty much spin on the spot. So bow thrusters are certainly not needed.

Edited September 17, 2010 by Phylis

[Jo Gilbertson]

If you want a good laugh hang around in or around Burton Waters on a sunny summer lunch time when all and sundry have come to their boats for their annual outing.

 

You get a lovely corus of bow thrusters, stern thrusters and labouring twin engines as the hopeless captains attempt to launch from their berths surrounded by a curtain of smoke. It is well worth the journey trust me. On days like this we stay firmly attached to our berth with a beer in hand watching the fabulous displays unfold.

 

ETA: For those who have never encountered a twin engined boat be it stern or shaft driven, you dont even need a steering wheel, you can manouvre them with the engines. One in forwards and one in reverse and they pretty much spin on the spot. So bow thrusters are certainly not needed.

 

I recall many years ago watching an RN patrol boat foraying up to York under Naburn Railway Bridge - holding station against a strong flood stream using just the power on the two propellors whilst their engineer dismantled the radar mast to get under the bridge - no bow thrusters there either ... the whole yacht club turned out to watch - very good boat handling ...

[Dominic M]

Would loved to have been a TNC slave. I've seen that photo of your wine and beer locker! I thought I did some good exploring back in the 90s when i was scribbling for WW but your exploits made mine look pedestrian.

 

Hydraulic BTs definitely the thing to have if you are going to have one, and why not a stainless steel tube (or is it not possible to make sound weld with the mild steel of the hull)?

 

I just can't (always*) get the "staff"!

Avast me hearty!...I like the cut of your jib!**....you would have made an excellent TNC slave crew member!

 

As for rust trap, here are a few things to throw into the pot, for you to pick apart, perhaps others can add some more....

 

Bowthruster should be in watertight compartment (done that one)

Bowthruster tube (and locker) should be corrosion protected on the internal (inside hull) surfaces (I have seen a NB with internal tube, partialy coverded with spray foam, over bare metal, tube merrily corroding away from the inside!)

Bowthruster locker should be well ventilated (from the top!), to stop condensation.

The correct grade / thickness of seamless tube should be used (many builders do not, as this is expensive).

The front anodes should be as near as possible to the bowthruster tube.

The bowthruster should be correctly and sufficiently sealed in the first place, so no water seapage adds to internal corrosion.

Bowthruster prop(s) nut(s)should have an anode fitted.

Bowthruster tube / hull join should be properly welded both sides. (I have seen a barge where the tube was only welded on the outside!)

Bowthruster battery should be isolated when boat laid up (I have seen a barge where the bowthruster batteries were not completely isolated from the bowthruster, this caused corrosion damage to the bowthruster / contactor, God know what it was doing to the tube)

Hydraulic bowthrusters will cause less corrosion to tube as no stray currents present, as with electric bowthrusters.

 

always*

TNC CWDF members are OK

 

**

Just getting in practice for Sunday

[Guest]

, and why not a stainless steel tube (or is it not possible to make sound weld with the mild steel of the hull)?

 

I'm defo. not an expert in this area but I seem to recall there is an issue with welding stainless to mild...

 

Somebody on here sure to know I expect..

[Neil TNC]

Would loved to have been a TNC slave. I've seen that photo of your wine and beer locker! I thought I did some good exploring back in the 90s when i was scribbling for WW but your exploits made mine look pedestrian.

 

Hydraulic BTs definitely the thing to have if you are going to have one, and why not a stainless steel tube (or is it not possible to make sound weld with the mild steel of the hull)?

 

Maurice A's rather small by barge standards 185mm x 2m seamless certified tube cost some £400 ...so gawd knows what a stainless one would have cost.

We had to keep the tube to 185mm, as MA has quite a "petit" bow. I did not want a larger tube with associated rear flutings into the hull.

It is certainly possible to make a sound weld between stainless steel and mild steel.

MA is having a Lewmar 9hp hydraulic thruster (with anode incorporated in prop nut), a respectable make and the one that packs the most oomph for the 185mm tube.

The 20m barge that I borrowed in France had a 15hp Sidepower / Sleipner 24v electric thruster, it was somewhat over powerful, the kick nearly knocked your wine glass / Belgian Abbey beer over!

 

Today I have mostly been sorting out the front lockers with Graham and Svarvik* the welder. As for stainless steel, MA is having a stainless steel anchor tube and stainless steel anchor pull plate. I would rather like stainless steel handrails, but don't think my budget will strech that far.

As for TNC slave...well openings available for doing the Royal, when it opens throughout (ICBA to do just the Shannon end. I missed the Dublin end being open, So I want to do the lot)... the way Waterways Ireland is phaffing about MA will probably be being trialed before that happens!...if not I can always borrow one of Riversdale's barges.

 

Svarvik* the chief Pole...MA will be an Anglo-Irish (ROI and NI)-Polish-Dutch Barge (yes I can claim it as being Dutch, as the plate came from Statendam in Holland!)

[Dominic M]

Why spoil the ship for a hap'orth of stainless steel, as the saying doesn't go?

 

I'd love to be a slave on the Royal. I did just about every inch of the rest including every mad backwater in Ireland i could find. Is that serious offer?

Edited September 17, 2010 by Dominic M

[Neil TNC]

Why spoil the ship for a hap'orth of stainless steel, as the saying doesn't go?

 

I'd love to be a slave on the Royal. I did just about every inch of the rest including every mad backwater in Ireland i could find. Is that serious offer?

 

The tube is now in....in fact it went in rather early (like a lot of stuff, diesel tanks, cooler tanks, weedhatch) this made it easy to get to the interior welds.

 

(yes, it will be shot blasted (Graham has his own plant) and re-epoxy primed before painting)

 

Steve the fabricator, who is experienced at welding stainless to mild said he would not be happy with that kind of structural joint below the waterline.

 

As for the Royal....Yes!

 

We certainly intend to stay in Ireland for 3-4 years, Mrs TNC should now be a bit more enthusiastic, as she has stumped up the money for the double glazed wheelhouse!