Weak links in the macgregor

[kadet]

our boats are perfect for coastal cruising

I love my but they are a compromise and they are perfect at what they are designed for. They are a comfortable, inexpensive, large volume fair-weather cruiser that both sails and motors. With modification they make adequate coastal cruisers in experienced hands, but they are far from perfect

Know your boat, know yourself, know the weather and your will be fine island hopping whgoffrn

This is what I have been doing for the past couple of years preparing my for some island hopping up the east coast of Australia when I take some pre-retirement leave, while I sail it around and learn it's abilities. I have purposely gone out in heavy weather, sailed 50 kilometers without relying on the motor and changed the sail plan twice to suit my needs from those experiences. This and many other things have taught me the limitations of my none of them have been a deal breaker and in some cases she has surprised me how well she has performed.

Perfect far from it, but so far capable

As Ixneigh alluded to, it will be more about your skill and prep work than the capabilities or weakness in your

[Mr Seas]

They always say "You will break long before your boat does" . Do you think this is true of the

[kadet]

They always say "You will break long before your boat does" . Do you think this is true of the

Yep,

The is just a big plastic bottle with built in flotation so as long as hull integrity is maintained it should not sink. Will it be livable after being demasted and rolled a few times

I have been caught out in force 6-7 winds, the boat broke a few sail fittings so had to motor 30 kilometers home took 6 hours and was completely exhausted when I got back. If I had to do that for more than 24hrs I definitely would have given up before the boat did as the ride was like a roller coaster. Though very uncomfortable the performed fine except for popping a few rivets rending the mainsail useless First mods after that was an autopilot, beefed up the mainsail control gear and got a heavier main with more reef points .

[Mr Seas]

I'm hoping I never have to face those kinds of conditions, but good to know the boat is strong enough to hold up.

[Bill at BOATS 4 SAIL]

I recently made aluminum rudders from a C-scow (I think) lee board, shaped more like those on the 26X, for my Mac 19, instead of the original Mac 19 almost square rudders. Based on the above, I think that I will double, or triple the aluminum, at least near the top, and carry a back-up rudder. Either have them riveted and/or welded together.
Bill at BOATS 4 SAIL

[Ixneigh]

My fat little 23 could maybe take more than I could.
Not the M I have to be careful with her.
Likewise the 22.2. Thought that centerboard was going to fall clean out of her. But it didn't. I feel better on the M without a huge peice of iron swinging around.
Elewise the 22.2 was a delight in the exumas except for her propensity to roll badly anchored in shallow water. I don't miss that about her.
Ix

[whgoffrn]

Let's hypothetically say someone was bored out of their mind and desperately needed a winter project anyway and felt they had a pretty good solution to the rudder bracket problem but couldn't wrap their head around a way to strengthen the rudders themselves......... Would it be a total waste of time to just make a new one from white oak.... solid white oak at the same thickness as the original hollow fiberglass ones would bound to be much much stronger right?

[kadet]

Let's hypothetically say someone was bored out of their mind and desperately needed a winter project anyway and felt they had a pretty good solution to the rudder bracket problem but couldn't wrap their head around a way to strengthen the rudders themselves......... Would it be a total waste of time to just make a new one from white oak.... solid white oak at the same thickness as the original hollow fiberglass ones would bound to be much much stronger right?

Yep

When I dreamed of building my Avalon Trimaran I came across this guys youtube channel, thought I would use this method if I ever had to build a rudder or daggerboard for the it gets the aerofoil shape so easily. For a rudder I think I would fill with chopped strain and resin not expanding foam.

https://www.youtube.com/watch?v=cfLjCxUkgP4

https://www.youtube.com/watch?v=xdSWXsCdBwE&t=32s

[Ixneigh]

I think plywood with plenty of fiberglass around it, and all solid glass at the rudder head would be ok. But why not just buy the ida rudders?
Ix

[sailboatmike]

I would be putting a 1/2 inch stainless bar down the middle of the rudder to give it some extra strength, this link has some interesting thoughts https://forums.sailboatowners.com/index ... et.176362/

The ruddercraft rudders would be nice but I think a pair is close to $1000 landed here in Australia, so building rudders is on my winter job list.

[whgoffrn]

I looked at their website bit for a macgregor 26x they didn't look like any kind of upgrade for strength more for airfoil shape unless I didn't read it close enough

[whgoffrn]

I considered bending rebar and a router to grind a grove for the rebar but then I have to wonder if my fiber glass skills are good enough to not rip the rebar out when it flexed.....i figured one big 1.5 inch wide white oak board would be stronger than the hollow ones we have and an easy solution .....at least I think white oak of equal width would be stronger???

[BOAT]

The rudder post is not strong enough for an unbreakable rudder - I have studied the rudders extensively - I removed the rudder posts to work on the steering mechanism so I could lay out it's geometry for my mods and noted the size of the bolts holding the rudder post brackets. I thought of enlarging those with big washers but ran into a problem: the thickness of the hull where those bolts go through is not thick enough.

That's why an unbreakable rudder is a bad idea: If you put on a steel rudder it will (as we all know) bend the rudder tangs on the top of the rudder - and you can make those rudder tangs out of some super metal that will never bend or break but if you do guess what happens?

The sideways torque of an unbreakable rudder will twist the rudder posts right out of the transom because the 4 tiny bolts holding the post brackets are seated in less than 1/4 inch of fiberglass - the fiberglass will just give way the the bolts will pull and allow the post brackets to release the post.

It's a tricky mechanism - if the rudder posts were a good 24 inches long there might be a chance - but with that short stubby little rudder post it will just torque right out - the soft brackets are a planned point of failure - you really can't do anything about it. Those rudder tangs are really only there to TURN the rudder - the real 'thing' that makes the rudder strong against the water is the ROPE! The rope is actually pulling the rudder through the water!

If you want the tangs to be unbending you need to do something then about the post brackets. Yout can't do anything about the post brackets unless you can get some really big bolts in some really thick fiberglass on the back. Th real "weak link" is the thin fiberglass around the rudder posts.

The only place where the fiberglass is thick enough to take any amount of sideways torque is the outboard well - the strongest rudder on the MAC is the outboard - put a rudder on the outboard and your bullet proof.

[Tomfoolery]

I considered bending rebar and a router to grind a grove for the rebar but then I have to wonder if my fiber glass skills are good enough to not rip the rebar out when it flexed.....i figured one big 1.5 inch wide white oak board would be stronger than the hollow ones we have and an easy solution .....at least I think white oak of equal width would be stronger???

What would far stronger, in general terms at least, would be to wrap the hinge end of the rudder in a stainless 'U' piece, with holes for the pivot pin, and a lot of little fasteners into the HDPE. Or all the way through if it's made of FRP with a hollow core. Lots of small ones will spread the shear load. Even if you had to rout a pocket for the 'U' piece so it didn't get any wider inside the bracket. Tapering it out some distance from the rudder brackets would be good, and the 'U' could be shaped to the full thickness of the existing rudder once out of the rudder bracket. It only has to be narrow where it wraps around the end of the rudder, but flare open wide otherwise.

The idea is to make a composite structure, which means it's a single structure made from differing materials, but all working together as a single unit. But it won't work unless the rudder is prevented from sliding inside the SS cover. At all. If it could be glued such that it actually help up, that would be ideal. But that's not practical (or even possible), so the next best thing is to fasten it with fasteners that prevent sliding motion. The same way old steel structures were built using rivets instead of welding - same principle.

But I don't know anything about the brackets or the support structure for said rudder bracket and post on an , so making a much stronger rudder is only that: a much stronger rudder. May not be in your best interest, as outlined by BOAT.

[whgoffrn]

BOAT after much thought I'd have to agree with you .... beefing up the rudder and then the bracket can be done and I may invest in a spare rudder and bracket anyway but you are right it will just move the point of failure to the other bracket bolted to the boat and rip it out of the hull unless a backing plate was put on....... the outboard is bolted through the transom and isn't going anywhere so yeah it definately is the strongest place..... any ideas on how to attach a rudder to an outboard ?????