Modification Impact Expert Advice Requested

[Captain Fantastic]

Level set - Over twenty-five years' experience modifying power boats to fit my needs, novice sailor. Versatility is more valuable to me than the best sailing, cabin cruiser, fishing boat or travel trailer. MacGregor 26M (7'9" Beam, length 25'10", water line Beam 23'2") used mostly as power boat 40% fishing Great lakes, Finger lakes, saltwater Delaware/Chesapeake Bays: 35% overnight both in water and as a travel trailer on land; 25% sailing for pleasure and for trolling while fishing.
Modification - apx. 6'5"" from deck, stern location, narrow fiberglass hard top center of the boat over steering wheel with attached platform on either side apx 4' off the deck give or take for sight lines. On the side decks will be a typical fishing boat seat with appropriate chrome safety railing, etc...
Question - Looking for thoughts on adding the modification so far stern of the boat with regards to safe weight distribution vertically and stern orientation. Understand a decrease in speed sailing and under power but lack understanding in tipyness and recovery sailboat factors. Thank you for your help and consideration.

 

[Tally Ho]

What does the new hard top weigh? Since the Mac26M is water-ballasted, and a bit tender on a good day, the weight up 6.5 feet above the deck could be an issue.

But if it isn’t too heavy, many boats carry some sort of Bimini over the cockpit. Most are canvas, but a hard top is also popular.

Greg

 

[Captain Fantastic]

What does the new hard top weigh? Since the Mac26M is water-ballasted, and a bit tender on a good day, the weight up 6.5 feet above the deck could be an issue.

But if it isn’t too heavy, many boats carry some sort of Bimini over the cockpit. Most are canvas, but a hard top is also popular.

Greg

Thank you for your reply the answer is TBD. Any thoughts on where too heavy starts? The higher narrow center hard top would not be weight bearing and would basically hold and distribute weight of the side platforms. As you alluded to, it certainly could be and maybe should be, something like chrome pipe framing with canvas. Would that make more sense weight wise?

 

[Tally Ho]

I don’t really know. I found a few photos of 26M’s with bimini’s…mostly some light tubing and canvas.


Those can’t weigh much.

i think I am most concerned with the “side decks…with a fishing chair mounted…”. Maybe I am not envisioning this right, but that sounds like a significant weight ( I weight 200 pounds) off-center, and 4 feet above the deck…

Do you have a sketch of what you are designing?

Greg

 

[Captain Fantastic]

Truth be told, I woke up from a nap today with the start of a solution that I questioned because of my lack of knowledge sailing characteristics and modifications to the stern so, I found and joined this forum this evening. I need to work through canvas verses a solid center piece and will try and sketch something out. LOL, it occurred to me when I posted that what I was envisioning would not be easily communicated, especially coming from a place of fishing first, sailing third or fourth. A sketch would help, and I will work on that. Thanks.

 

[dlochner]

It sounds like you want a large T-Top to provide shade while fishing. You are correct to be concerned about weight. Height is going to be an issue, I doubt you can attain a 6.5' height above the deck and still have a boom for the mainsail. 6.5' above the cockpit sole is doable.

@Tally Ho suggestion about a canvas (sunbrella) bimini is a good suggestion. It will be lighter and easier to manage. Aluminum tubing can be used to save weight, however it is not as secure as stainless tubing when someone grabs onto it (and someone will). Do not use chromed piping, the underlying steel will rust and the chrome plating wear off.

I think you understand the more versatile you make the boat, the less it performs any of its tasks well.

Good luck.

 

[shemandr]

As far as the fishing chair goes I'd add that many sailers sit on the high side of the cockpit or deck. That actually helps with the heeling. So, I don't think of the weight of the chair + person is a problem. Just fish from the high side.
I think sailing boats make an excellent platform for trolling. They are stealthy. Since trolling is largely about speed you will need to learn to adjust the amount and trim of sails to get the speed you want. It will be fun!

 

[Captain Fantastic]

Thanks for the advice and it's an old guy thing. Top capability fads at a certain age, it's more just doing the things I enjoy over performance. I really didn't explain my actual goal very well and skipped to my initial potential solution, which was more power boat thinking but, it was like 2:00 am, My actual goal is simply to have two swivel seats with the ability to face out the stern and side. I ran across a professional mod that had raised bow facing seats in the stern corners, really just some tubing and small flat fiberglass platforms $900 each. That had me thinking of mounting stern facing seats on a raised platform, which led me to a center T-top like concept in support of the raised mounting platforms on the side. The actual T-top concept in and of itself, other than as support if required isn't something need. I believe I might have overreacted what was needed to meet the goal. Perhaps a better solution would be a starboard to port bench connecting the side seats across directly in front of the helm steering tower. The bench would have four flush seat post receivers, two near center line for longer power travels, managing weight distribution with a more comfortable forward-facing ride. They would also be out of the way when under sail. The bench would also have a post receiver close to each side to move the seats facing stern seaward for fishing. The seats would be an added comfort when in the slip. They bench would provide addition storage and live well capabilities. Other than not tripping over the bench, I think this might be my solution. Thoughts?

 

[Sailor Sue]

Where would your head be in relation to the boom using any of these seats?

 

[captcoho]

Understand a decrease in speed sailing and under power but lack understanding in tipyness and recovery sailboat factors. Thank you for your help and consideration.

Adding weight should not have an effect to the speed when sailing. It may require more sail and trim to reach hull speed of about 6.4 kts. Power/weight with a motor is less than 20 kts while under power with no water ballast. Adding weight may require maxing out with a 70hp, which will also be adding more weight.

 

[Captain Fantastic]

Adding weight should not have an effect to the speed when sailing. It may require more sail and trim to reach hull speed of about 6.4 kts. Power/weight with a motor is less than 20 kts while under power with no water ballast. Adding weight may require maxing out with a 70hp, which will also be adding more weight.

Thank you for the excellent advice.

 

[Captain Fantastic]

Where would your head be in relation to the boom using any of these seats?

Thank you for your response they would be out of range when the seats are to the sides there could be an issue when they are toward the center, great point for consideration.

 

[dlochner]

The issue with weight is not the weight as it is the placement of the weight. Weight placement affects stability. Weight high decreases stability, meaning the boat will be tippier and if too much weight is too high the boat would be more likely to capsize.

If I recall correctly the Mac 26M has a fairly hard chine and flat bottom. Hard chine boats have a lot of initial stability, however, at a certain point they quickly become unstable. Boats with softer chines or rounded bottoms will be initially tippy however as they heel over stability increases and it becomes harder to tip more.

Adding 400 pounds is like having 2 crew. In the cockpit or on deck they increase stability, especially if they sit on the high side. If the two decide to get rambunctious and climb 10 feet up the mast, the boat will become much less stable because the weight is much higher.

However this project goes, keeping weight low is good. A hard top bimini could be constructed, a lighter canvas one would be better, at least in terms of boat stability.

 

[jssailem]

WELCOME Capt Fantastic to the SBO forum.
The MacGregor sounds like the boat design you would find supportive for most of the adventures you identify. Altering the boat design will impact the boats handling and stability by either increasing or decreasing the designed functions. As stated by @dlochner "weight Placement" is an important element in design. You indicate a plan for "Atlantic Ocean" sailing. Moving the CG higher in the air will reduce stability while sailing or negotiating large waves. In high winds, every structure high above the boats' water line will capture the wind and act like a sail. A hard Bimini will not be removable when the wind kicks up.

With water ballast and hull design the boat was designed to handle certain conditions. You will want to understand the design of the boat, in order to evaluate the design compromises you will be doing to the boat as you modify it to your needs. It is informative to boat designers, to wander the marina and see how the powerboats do at the dock when the gail force winds blow. My observation is that the boats with the 3 level fly bridges tend to be blown about more than the boats with just a deck cabin.

Sounds like an interesting project. Let us know how it goes.

Being a sailor, I understand the MacGregor 26 design was a compromise between a sailboat and a motor boat.