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Hello guys, i'm new to the forum AND to sailing. I figured I would get into sailing to catch a break from gas prices in my powerboat.

But..

Here's my problem. The boat I chose to purchase is a Tanzer 7.5. I did my research on the actual model prior to buying and read it was decent for beginners, but the gentleman I purchased it from cut off a little more than half of the keel. The draft was originally 4 foot, he said he cut it off to get in closer to shore and he basically used it as a powerboat as he took down the mast and used an outboard.

Now the mounting for the mast and sails is intact so thats not the issue. He kept the piece of keel he removed. I spent a day dragging the keel to the boat, standing it up, and grinding the surface to prep it for welding. But when I called the welder out, he informed me he wouldn't feel comfortable welding it back together since it's iron it would start to crack once he heats it.

So that leaves me in a dilemna, which is why I'm here hoping someone can give me some solid advice.

1. Do I just try another welder?

2. Do you think I would be fine leaving it as is?

3. If not, is there another viable fix?

4. Is the boat just a big paper weight now. :(

My original plan was to get it welded and bolt a galvanized steel plate on either side for extra stability.... I'll try and take some pics tomorrow if that will help. All input is welcome and thanks in advance!
 

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One of None
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Welcome aboard! you should have joined before you bought a boat!

Anyways... do you actually own this boat yet? I know of no practical way to reattach the cutoff peice except by drilling holes through it and putting lag bolts into the bottom of the existing lead keel even then it's chancey.

Oops just reread your post it's iron???
 

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LOL take both pieces and heat them cherry red in a fire, now you can put the torch to them and they won't crack.
Pretty common boat, if your hull is in exceptional shape you can probably find a near freebie wreck and use the keel.
Easier to buy a new boat.
 

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Discussion Starter #4
Welcome aboard! you should have joined before you bought a boat!

Anyways... do you actually own this boat yet? I know of no practical way to reattach the cutoff peice except by drilling holes through it and putting lag bolts into the bottom of the existing lead keel even then it's chancey.

Oops just reread your post it's iron???
Thanks! I know but I'm an impulse buyer so just grabbed it when I saw the deal.

Yes it's iron, does that change your solution?? Thanks for the input..
 

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Discussion Starter #5
LOL take both pieces and heat them cherry red in a fire, now you can put the torch to them and they won't crack.
Pretty common boat, if your hull is in exceptional shape you can probably find a near freebie wreck and use the keel.
Easier to buy a new boat.
Hey Tanski,

If I do it the way you suggest do you think that will be stable enough? Or should I bolt it with plating on both sides after?

It definitely would be easier to buy a new boat, just not cheaper, ha!

The rest of the boat however is in great shape, down to the seat cushions. Hull is 9.5/10. Sails were never used. Part of the reason I want to get this keel situated is because if I get it right seems like ill have a good starter sailboat!

Thanks for the input.
 

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One of None
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How about some pictures maybe we can give you a better answer.
 

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No you can't use it as a sailboat with that keel. Not enough stability.

It may be possible to weld it, but I wouldn't trust it for very long in other than sheltered waters. I think you may have wasted your money because it looked like a "deal".
 

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One of None
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Cast iron is extremely difficult to drill even with top rated industrial drill bits.

through bolts would probably be the only thing that would work.

I hesitate to suggest this idea but the both pieces after being bolted or welded together, could brcompletely encapsulated in fiberglass then rebolted to the boat. The keel shoe/ stub on the boat should be reinforced and rebuilt & faired also. Or find another boat that's wrecked and has a somewhat similar keel!
 

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Living the dream
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Cast iron can be structurally welded. The railways used to do it all the time many moons ago using gas welding and actual cast iron rods. You probably can't do this on a keel, but you can use arc welding. The trick is to use welding electrodes that have high nickel content. Something like 312 stainless steel or, even better, specialty nickel alloy electrodes specifically for the purpose of joining cast iron. You then need to find a welder that has the experience to weld it all up. The downside is that it will probably cost much more to do then the boat is worth.

Perhaps the most viable option, if it's possible, is two hunt down a replacement keel.
 

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You usually would have to remove it and heat it evenly and then while both parts are hot weld it back together.

An experienced welder will know how to do this and will have the appropriate burners for heating large objects and the correct alloy of arc welding rods. Most younger welders are only going to be wire feed knowledgeable however old timers, especially those that work on farm or construction equipment will know how to deal with welding large cast iron objects that carry a heavy load.

Sometimes I will put smaller cast iron items across 1 or 2 gas camp stoves to preheat them for welding as long as they are not too thick as I no longer have my higher amperage equipment and only have a small wire feed unit that is only good for up to a tad over 1/4".

The iron has to be dry and relatively oil free so it may need to be kept moderately hot for a few hours before welding to ensure enough moisture has been driven out to minimize splatter.

Now if you have a Pulsed TIG machine you may be able to weld some cast iron without preheating it however I am not sure of at what thickness this becomes inadvisable as my training was on stick welding steel beams and heavier plate steel.
 

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Where are you located? I own a Tanzer 7.5 but it's a shoal keel so it won't do you any good. However if you live anyone in Ontario these boats are a dime a dozen, should be easy to find one for cheap on a trailer. I had a friend who told me he was shopping in Port Dover area and there were a couple 7.5's for FREE at the marina if someone would cart them off.

Honestly there's just no good, cheap, easy, way to weld back an iron fin keel. The guy who did that wasn't thinking. Safest and cheapest options:

1) Get another 7.5 and use this one for parts.
2) Get another 7.5 as parts and swap keels.

No plates or welds will get you a safe economical fix. The first heavy weather you will find yourself in, especially in a small boat, you want to have faith it won't turn upside down, which is what will happen when half your keel falls off.
 

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Discussion Starter #12
Where are you located? I own a Tanzer 7.5 but it's a shoal keel so it won't do you any good. However if you live anyone in Ontario these boats are a dime a dozen, should be easy to find one for cheap on a trailer. I had a friend who told me he was shopping in Port Dover area and there were a couple 7.5's for FREE at the marina if someone would cart them off.

Honestly there's just no good, cheap, easy, way to weld back an iron fin keel. The guy who did that wasn't thinking. Safest and cheapest options:

1) Get another 7.5 and use this one for parts.
2) Get another 7.5 as parts and swap keels.

No plates or welds will get you a safe economical fix. The first heavy weather you will find yourself in, especially in a small boat, you want to have faith it won't turn upside down, which is what will happen when half your keel falls off.
Thanks for the feedback! Are you selling your Tanzer? Im in Maryland, however Ive been in Toronto at least 4 times just this year so that might make sense to look or one near there.
 

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Discussion Starter #13
You usually would have to remove it and heat it evenly and then while both parts are hot weld it back together.

An experienced welder will know how to do this and will have the appropriate burners for heating large objects and the correct alloy of arc welding rods. Most younger welders are only going to be wire feed knowledgeable however old timers, especially those that work on farm or construction equipment will know how to deal with welding large cast iron objects that carry a heavy load.

Sometimes I will put smaller cast iron items across 1 or 2 gas camp stoves to preheat them for welding as long as they are not too thick as I no longer have my higher amperage equipment and only have a small wire feed unit that is only good for up to a tad over 1/4".

The iron has to be dry and relatively oil free so it may need to be kept moderately hot for a few hours before welding to ensure enough moisture has been driven out to minimize splatter.

Now if you have a Pulsed TIG machine you may be able to weld some cast iron without preheating it however I am not sure of at what thickness this becomes inadvisable as my training was on stick welding steel beams and heavier plate steel.
It seems an experienced welder is hard to find here unfortunately. I have a stick welder but this is definitely beyond my 'expertise'. Thanks for the input.
 

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One of None
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I think I found your boat!
http://m.sailboatlistings.com/view/31477
I guess I need to CLARIFY! When I said I found his boat I meant a boat Like HIS, cut off fin Keel version

In case anybody was still wondering, the LINK is to a SHOAL draft version

And to all the naysayers, (and I'm one of them, )
someone is rarely talked out of doing something they know they shouldn't do even though they asked everybody if they should!
 

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One of None
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Keel Cutters, there seems to be a whole new type of mentality developing with people that want to do the Great Loop they seem to think cutting the Keel off of a perfectly good sailboat will give them a "Looper" I actually have a discussion about this on the woodenboat forum.

Looking at the Joint you could fill with epoxy and wrap itall the way around with a wide band, lots and lots of screws into tapped holes, countersunk into the metal band,

trouble is it will rust in short order and because it's against iron will Rust even faster. It should work because screws and bolts resist shearing forces very well.
Oh boy... That means people do this often?? Thats not mine but it is close to home. I'm in Maryland. I posted pictures by the way. Hopefully that helps.
 

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Tried to add pics to my original post but failed so adding inside the post
Won't work that way. even if you are to weld it. it will not be as strong as it was cast in one piece. cast iron that size will need to preheated to about 900 degrees before welding. the weld would have to be 100 percent weld thur the cross section. and making matters even worse the bigger part of the weight of that keel is in the bottom half
what could go wrong? the keel breaks off and the boat flips over and hopefully not one is hurt. but you will make the News reader on sailnet
 

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The boat for sale linked above is indeed a SHOAL version of the T7.5. I own one, the keel is longer than the fin version (lengthwise). Tanzer did a good job with their shoal version, instead of just cutting off their fin and then adding more weight they actually made a separate design for the shoal.

My old T7.5 isn't for sale just yet, thanks for asking (Sudbury area). I do have 2-3 friends asking to buy her since they know the work I put in (new sails, standing rig, autopilot, engine rebuild, solar, charplotter, the list goes on...). Bug me sometime and maybe I'll change my mind, but who knows.

I am serious though, I truly would not try an repairs (none that would be economical) other than replacing the keel with a parts boat one. It's just too much of a safety hazard, the keel sees alot of force, alot of corrosion over time, and although it's "just a 25ft boat" it's still big enough to hurt or kill someone if it were to fail. My point is it's not a little hobie cat that could be junkyard fixed "in the name of science" and see if it fails.

If you're curious I have some videos sailing my T7.5 in the link on my sig, youtube "SV Breezy". Nothing fancy, just some fun times on that old boat. I hope things work out for you in the end, remember these are cheap and plentiful.
 
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