How fast should a boat be for offshore

[Damon7]

5 minutes ago, zmk1962 said:

Thats the design of any boat that has a through hull shaft drive prop.  They have a keel and rudder.

The alternatives are, an inboard with the drive leg outside the stern, or a pod with outboards.

Cheers Z

Ok thank you Zoran so maybe it's not a semi-displacment hull then. Would that setup effect planning at all.

Thank you Damon 

[zmk1962]

I believe its a semi displacement like you say... I don't know of any of that style that actually plane like outboard or stern drive versions .... regardless, the modern Arvor (displacement hulls) with shaft drive claim top speed of 20kts...

Cheers Z 

[slowjigger]

30 minutes ago, zmk1962 said:

I believe its a semi displacement like you say... I don't know of any of that style that actually plane like outboard or stern drive versions .... regardless, the modern Arvor (displacement hulls) with shaft drive claim top speed of 20kts...

Cheers Z 

I think the Arvor is semi-displacement as well. 

[Damon7]

1 hour ago, zmk1962 said:

I believe its a semi displacement like you say... I don't know of any of that style that actually plane like outboard or stern drive versions .... regardless, the modern Arvor (displacement hulls) with shaft drive claim top speed of 20kts...

Cheers Z 

Ok thank you Zoran.

I believe my approach may just be a larger diesel engine in the future to achieve that extra speed when needed. Thank you for your advice.

Damon.

[rickmarlin62]

They are not a displacement hull  put a decent deisel motor round 150 plus hp and you will be surprised how well they handle

[Damon7]

30 minutes ago, rickmarlin62 said:

They are not a displacement hull  put a decent deisel motor round 150 plus hp and you will be surprised how well they handle

Hi Rick did you see my previous reply where I quoted you. Are you able to remember what style of the two your bluefin was. Thank you Damon.

[tryhard]

Hi Damon7,

I am following thus thread with interest.

I have what they refer to as a pocket game boat.

My  contribution to this thread is to warn you of the costs related to running a larger boat, particularly re-powering..

If you can, I would highly recommend finding something that already has the power that you need!

Unless of course you are paying a "hull only" price and are prepared to over capitalise on a very old boat.

The bigger the boat the more the costs rise exponentially.

Don't get me wrong, I  spent many days as a pre teen on my uncles Savage Bluefin and I recall it being very capable vessel.

But you are looking at a very old boat with all the associated issues - who knows what else will need to be done.

If your are happy to spend the big bucks to build the boat you want, then go for it.

If the boat doesn't already do want you want, have a serious think about it.

Whatever you decide, I wish you the best outcome.

Good luck.

[Damon7]

58 minutes ago, tryhard said:

Hi Damon7,

I am following thus thread with interest.

I have what they refer to as a pocket game boat.

My  contribution to this thread is to warn you of the costs related to running a larger boat, particularly re-powering..

If you can, I would highly recommend finding something that already has the power that you need!

Unless of course you are paying a "hull only" price and are prepared to over capitalise on a very old boat.

The bigger the boat the more the costs rise exponentially.

Don't get me wrong, I  spent many days as a pre teen on my uncles Savage Bluefin and I recall it being very capable vessel.

But you are looking at a very old boat with all the associated issues - who knows what else will need to be done.

If your are happy to spend the big bucks to build the boat you want, then go for it.

If the boat doesn't already do want you want, have a serious think about it.

Whatever you decide, I wish you the best outcome.

Good luck.

Thank you for your advice and input I appreciate what you have said and definitely see what you are saying. I was and still am very happy for the boat the way it is but I do want to make sure it is capable to do the job. But you are right I don't want nor can afford large cost all all the time. Out of interest what is your Pocket game boat.

[JonD]

I think 98kh would be perfect, any slower would be boring and any faster would be scary!!!!!

Seriously though there are a huge amount of variables to the question. The further offshore you plan to head then the faster the boat is can be a huge advantage. Firstly getting there and having time left in the day to fish. Putting the throttle down to beat bad weather home is also a good thing.

Crossing any bar in a slow boat is down right dangerous. You need power on tap both heading out through swell conditions and coming back in. Ive had days coming in through bars where Ive had to run some of my boats full throttle trying to stay with swell. Ive also had occasions where running at 30kts in a 30kt southery from the seamounts in 5m boats has been quite comfortable, where Ive left far bigger heavier boats in my wake. Things change dramatically if I get caught in a westerly though as I run pretty much head into it to get home and I soon wish I was in a far bigger boat. 

Little boats as described as pocket game boats can be extremely good fun in big seas as you drive them more like a mountain or motocross bikes etc, steering and throttling your way in and out of swells and breaking waves. They respond quickly and you become in a zone of fast steering, feeling like the boat becomes part of you and not just something you are heading towards port. 

 

[Damon7]

1 hour ago, JonD said:

I think 98kh would be perfect, any slower would be boring and any faster would be scary!!!!!

Seriously though there are a huge amount of variables to the question. The further offshore you plan to head then the faster the boat is can be a huge advantage. Firstly getting there and having time left in the day to fish. Putting the throttle down to beat bad weather home is also a good thing.

Crossing any bar in a slow boat is down right dangerous. You need power on tap both heading out through swell conditions and coming back in. Ive had days coming in through bars where Ive had to run some of my boats full throttle trying to stay with swell. Ive also had occasions where running at 30kts in a 30kt southery from the seamounts in 5m boats has been quite comfortable, where Ive left far bigger heavier boats in my wake. Things change dramatically if I get caught in a westerly though as I run pretty much head into it to get home and I soon wish I was in a far bigger boat. 

Little boats as described as pocket game boats can be extremely good fun in big seas as you drive them more like a mountain or motocross bikes etc, steering and throttling your way in and out of swells and breaking waves. They respond quickly and you become in a zone of fast steering, feeling like the boat becomes part of you and not just something you are heading towards port. 

 

Thank you JonD 

I understand what you are saying I guess the trip out doesn't bother me much as there is good trolling to be had almost the whole way and usually we only fish for a hour or two on a spot at a reef and most the best fish seem to come up in that first session then we usually move on. I don't want something foolishly unsafe at all but taking my time to get there is ok. Thankfully we don't have any bar crossing up here in FNQ and I guess it's more chop then swell but it can still get unfavorable at times. At the moment we have a little Mustang 1500 and it's a good little boat but a bit small with all of us and a bit rough on the kids coming back in rough conditions as there only young. We use to have a pride Montego which was around 5.5m - 5.7m and it handled great but the transom was wet and with a 130b Yamaha on it the fuel consumption was very high about 1l to 1km. From what I can see the down side to slow speeds up here for us is gonna be not being able to out run bad weather.

Thank you Damon

 

 

 

 

[tryhard]

8 hours ago, Damon7 said:

Thank you for your advice and input I appreciate what you have said and definitely see what you are saying. I was and still am very happy for the boat the way it is but I do want to make sure it is capable to do the job. But you are right I don't want nor can afford large cost all all the time. Out of interest what is your Pocket game boat.

Carribean 28 twin shaft diesels

[zmk1962]

Just two more comments on this topic ... 

1 hour ago, tryhard said:

Carribean 28 twin shaft diesels

Nice. Pretty much the same size as Gils Bertram 25s with 2x Mercruiser 3L .. 

6 hours ago, Damon7 said:

From what I can see the down side to slow speeds up here for us is gonna be not being able to out run bad weather.

 

Actually outrunning the weather is ideal, BUT many times you can't out run it completely...

Note: a 2m tall person sees the horizon at around 5-6km away. A storm travelling at 60kmh will be on you in 6min .... you may stay ahead of it for a while but it will catch up with you eventually.

Having the power on tap to control your craft and keep it facing the waves and wind is paramount so that you don't get rolled or capsized - that was what the guys in the "perfect storm" video managed to do and it undoubtedly kept them out of the drink.

I personally doubt something that can only deliver max 10kts will be enough to control a 22ft boat in anything but calm weather.

Anyway, I think you said somewhere above you have already purchased the vessel. I've given my views on the question asked, apologies if its not what you wanted to hear. All I can suggest is go slow in building experience with the rig in varying conditions before taking her wide.

Cheers and stay safe.

Zoran

Edited December 29, 2022 by zmk1962

[Damon7]

1 hour ago, zmk1962 said:

Just two more comments on this topic ... 

Nice. Pretty much the same size as Gils Bertram 25s with 2x Mercruiser 3L .. 

Actually outrunning the weather is ideal, BUT many times you can't out run it completely...

Note: a 2m tall person sees the horizon at around 5-6km away. A storm travelling at 60kmh will be on you in 6min .... you may stay ahead of it for a while but it will catch up with you eventually.

Having the power on tap to control your craft and keep it facing the waves and wind is paramount so that you don't get rolled or capsized - that was what the guys in the "perfect storm" video managed to do and it undoubtedly kept them out of the drink.

I personally doubt something that can only deliver max 10kts will be enough to control a 22ft boat in anything but calm weather.

Anyway, I think you said somewhere above you have already purchased the vessel. I've given my views on the question asked, apologies if its not what you wanted to hear. All I can suggest is go slow in building experience with the rig in varying conditions before taking her wide.

Cheers and stay safe.

Zoran

Thank you Zoran for all your advice and input.

Damon.

[Damon7]

1 hour ago, tryhard said:

Carribean 28 twin shaft diesels

As much as that is a really nice boat it wasn't what I expected to be called a pocket game boat. I was thinking something around 5m or less but maybe that just shows my lack of knowledge regarding it all.

Thank you Damon.

[noelm]

A boat that can only do 10k will be capable of keeping pointed into the sea, speed is not the be all to end all (it is nice to have though) seakeeping qualities are not about speed. All that said (in my opinion) that boat will drive you nuts and slowly send you broke, not too sure which will happen first. It would be fine for "putting" around Pittwater/Sydney Harbour or Botany Bay, but going offshore will be safe enough, and fine for close in reef fishing, but anything further out is going to be a very long day.

[Damon7]

3 minutes ago, noelm said:

A boat that can only do 10k will be capable of keeping pointed into the sea, speed is not the be all to end all (it is nice to have though) seakeeping qualities are not about speed. All that said (in my opinion) that boat will drive you nuts and slowly send you broke, not too sure which will happen first. It would be fine for "putting" around Pittwater/Sydney Harbour or Botany Bay, but going offshore will be safe enough, and fine for close in reef fishing, but anything further out is going to be a very long day.

Thank you Noelm for your input. I understand why you say it could drive me mad but why do you say slowly send me broke ( is it the expense if I start repowering and upgrading stuff or something else).

Thank you Damon.

[noelm]

OK, first up, it's old, old boats, motors and associated gear require constant maintenance. Is it on a trailer, or will it be moored? The picture you posted shows it on some kind of stand. Launching and retrieving an inboard boat is a challenge at best, it will need to be floated off the trailer because of the prop being down so low, a big tow vehicle will be required. If it's moored, then you are really throwing money into the water, constant maintenance and mooring fees will add up quick, not to mention carrying all you gear to and from the boat every time you want to go out will get old very quick too. Repowering that boat is out of the question, unless you can dig up an old motor, gearbox and prop  for near free and you do all the work yourself, including glassing in engine beds and mounts, then you have to find out if the shaft is big enough for more HP, changing that is out of the question.

edit........if it is moored, does it come with a mooring? if so, is it reasonably close to home?

Edited December 29, 2022 by noelm
Added something

[noelm]

Just to add, no one is trying to scare you off, but, many here have years of experience and don't want to see you posting about your misfortune in 6 months time! I personally wouldn't touch that boat for any more than near free, and even then it's not a great option, in my opinion only......

[Damon7]

1 minute ago, noelm said:

OK, first up, it's old, old boats, motors and associated gear require constant maintenance. Is it on a trailer, or will it be moored? Launching and retrieving an inboard boat is a challenge at best, it will need to be floated off the trailer because of the prop being down so low, a big tow vehicle will be required. If it's moored, then you are really throwing money into the water, constant maintenance and mooring fees will add up quick, not to mention carrying all you gear to and from the boat every time you want to go out will get old very quick too. Repowering that boat is out of the question, unless you can dig up an old motor, gearbox and prop  for near free and you do all the work yourself, including glassing in engine beds and mounts, then you have to find out if the shaft is big enough for more HP, changing that is out of the question.

Thank you Noelm 

This is some really practical advice I need to hear and understand. Please allow me to tell you how I was planning on using the boat. The boat will be on a trailer. I am planning on storing the boat close to the boat ramp and towing it with our turbo diesel Toyota Prado. The current owner tells me the boat is 2t on the trailer. We have a very nice facilities/ ramp at mourilyan harbour and I would float the boat of beside the padded dock and back on. Thank you again.

Damon.

[noelm]

Just looking at the picture again, my guess is "semi displacement" is termed simply because it's only got a tiny motor in it, looks just like the stern drive version that has had a shaft drive motor installed (from the factory I guess) 

[Damon7]

4 minutes ago, noelm said:

Just to add, no one is trying to scare you off, but, many here have years of experience and don't want to see you posting about your misfortune in 6 months time! I personally wouldn't touch that boat for any more than near free, and even then it's not a great option, in my opinion only......

I understand no one is out there just to scare me off I really do appreciate all the advice. As Zoran said I have already put a deposit on the boat but understanding what I'm in for and how much it is worth and possible problems is something I need too know. I am taking in everything everyone has said and thinking on it. As far as work on the boat I can definitely do all the fibreglass work myself having some experience and and I can definitely do all the engine work myself. But when it comes to the inboard side of things like shaft and prop and any associated bearings and gear boxes I've never had anything to do with them. As I said I do really appreciate all your input.

Thank you Damon.

[noelm]

I think the person that told you it's 2t is dreaming!

[Damon7]

5 minutes ago, noelm said:

I think the person that told you it's 2t is dreaming!

Well that indeed is a problem if your right. The Prado has a 2.5t towing capacity so anything above that I'm not really interested in towing. In his photos he appears to be towing it with a Mitsubishi Pajero which would be of similar weight and hp but I guess that doesn't mean much. How much do you think it would weigh Noelm. And anyone else reading this with a similar size boat that knows there wieght would be great thank you.

Damon 

[zmk1962]

58 minutes ago, noelm said:

A boat that can only do 10k will be capable of keeping pointed into the sea

Sorry Noel, I don't agree.  We are talking about a 2T 22ft FG hull and max 10kts capability under ideal conditions. Factor in 2 adults, 5 kids, gear, provisions etc we are talking about 2.6T on the water ... add some breaking waves, high wind gusts .... and I doubt a rudder steer boat of that size, with that little power can be swung around or manoeuvred at the speed required. As you know, once you are knocked side on to a breaking wave you are very exposed to being rolled and capsized. .. you either run infront of the wave or turn to face it.   

barrycuda was 22ft 2.6T FG rig + crew with a 200hp merc outboard when BarryC, Wayno and I were caught in a squall coming back from browns ... 3m seas, white caps ... I had the 200hp swinging side to side and throttle full down at times to get the boat positioned correctly.   That's just my experience with a hull of that size.  I was happy to replace the 200hp with the new 150hp ... as it gave me the same low down torque to push the hull around if I ever encountered those conditions again. 

Cheers Zoran

Edited December 29, 2022 by zmk1962

[zmk1962]

2 minutes ago, Damon7 said:

Well that indeed is a problem if your right. The Prado has a 2.5t towing capacity so anything above that I'm not really interested in towing. In his photos he appears to be towing it with a Mitsubishi Pajero which would be of similar weight and hp but I guess that doesn't mean much. How much do you think it would weigh Noelm. And anyone else reading this with a similar size boat that knows there wieght would be great thank you.

Damon 

I agree with Noel its probably over 2T.  How much fuel? water? gear? batteries? + + +

Also the trailer is 500-600kg ... so even if it came to 2T for boat ... you are already at max 2.5T for the car with the boat + trailer.

Cheers Zoran