Mast with weld repair - stay away or worry not?

Jan 24, 2022
8
Vandenstadt & McGruer Siren 17 Sister Bay
hi everyone
I spoke with a seller of an O'Day Mariner 19 before seeing the boat in-person. He told me that a previous owner had the mast repaired by welding it back together. He didn't know the circumstances that led to its disrepair but did say that he was able to sail her on Lake Michigan. He's going to send me pics of the weld but his description said the weld goes all the way around the circumference of the mast. Before I go through the trouble of driving up to see the boat, do I even bother? Is a welded mast just too risky to sail on, generally speaking, or is it something that can be reliable? Thank you
BK
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Please post a photo of mast weld. Was it a crack or complete fracture? If the latter, if the mast had a sleeve insert and welded, then OK otherwise plan to repair the mast.
 
Jan 24, 2022
8
Vandenstadt & McGruer Siren 17 Sister Bay
I don't have pics of it unfortunately - and the owner couldn't speak to the circumstances of what led to the break. So, I don't know if there's a sleeve or not. I'm thinking I'll pass on this one because it's just too big an unknown
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
Information is you friend. I would not be concerned IF I knew what the repair looked like.
 

Johnb

.
Jan 22, 2008
1,461
Hunter 37-cutter Richmond CA
There is so much you don't know and can't find out with certainty that I would turn away while you still have the money and he has the boat.
 
Jan 24, 2022
8
Vandenstadt & McGruer Siren 17 Sister Bay
yeah, that affirms what i was already thinking - but you found the right words!
 
Jan 24, 2022
8
Vandenstadt & McGruer Siren 17 Sister Bay
i'm familiar with their show. appears they are a useful source of wisdom!
 
Feb 18, 2022
440
Catalina 36 Port Orchard
I have to agree here with others in the let’s see it part.

Here is my concern, a butt weld is the weakest of all types of welds and one of the hardest to get perfect penetration for the length of the weld. Not to say it can’t be done, just that its not as easy or as strong as a lap weld which would be many times stronger. Another issue with a butt weld is the heat fatigue on the metal around the weld. Honestly the weld itself is not where the break will occur if the weld is decent, it’s the area just outside the area that got hot. Usually this is 1/4 to 1/2 an inch away from the weld depending on the welding method. In the case of an aluminum mast the current best way to weld is TIG but a MIG welder can also do the job, just not as clean.

So either walk away, or have the mast inspected… or be prepared to buy a mast which may cost more than the boat in some cases.
 
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jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,080
CAL 35 Cruiser #21 moored EVERETT WA
Finding a boat is a commitment. I drove 250 miles to inspect my boat.
Have a friend who talked with the owner, did a video walk thru, traveled 1400 miles only to find the boat was a wreck.
You got to commit to the adventure. If your not feeling good about the travel, then walk away. The most expensive boat you will ever find is the one listed as "Free to a Good Home".
You do not want too buy another persons damaged problems. A bad mast does not heal like a broken bone. On a 19ft boat the masts are not made for a lifetime of hard sailing or damage survival. If you go the distance you should be budgeting in the replacement of the mast. If you can not stomach buying a replacement, then my advise would be Walk Away.

Oh and the guy who traveled 1400 miles... 3 weeks later found a boat near his home and it was Perfect.
You just never know.
 
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RussC

.
Sep 11, 2015
1,611
Merit 22- Oregon lakes
Also depends greatly on exactly where the break was on the mast. high up, mid, or down low would have a huge impact on the stress levels on the repaired area.
 
Nov 26, 2012
1,654
C&C 40-2 Berkeley
I would say that you would need to know for sure that the repair is good. Otherwise don't risk it. Welding aluminum is dicey. Even when done correctly it reduces the strength of the aluminum in the vicinity of the weld by half. I think I would have to pass unless I could be convinced by an expert that the mast is good.
 
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Dec 27, 2012
587
Precision Precision 28 St Augustine
My last boat was a O’day 240. She was a great boat. I didn’t native until months after purchase that the mast base appeared to have been welded on. The weld work was sloppy so I really don’t think it was factory. My suspicions where heightened by some abrasion marks on the mast. It appeared as though it was demanded at some point in its life.
The weld never gave me a problem.
 
Mar 26, 2011
3,699
Corsair F-24 MK I Deale, MD
...a butt weld is the weakest of all types of welds and one of the hardest to get perfect penetration for the length of the weld. Not to say it can’t be done, just that its not as easy or as strong as a lap weld which would be many times stronger. Another issue with a butt weld is the heat fatigue on the metal around the weld. Honestly the weld itself is not where the break will occur if the weld is decent, it’s the area just outside the area that got hot. Usually this is 1/4 to 1/2 an inch away from the weld depending on the welding method. In the case of an aluminum mast the current best way to weld is TIG but a MIG welder can also do the job, just not as clean.

So either walk away, or have the mast inspected… or be prepared to buy a mast which may cost more than the boat in some cases.
Yes... and no.

A full penetration butt weld is 100% strength in most codes, but a lap weld is 50%. Easily Googled. This feels counter intuative, but it is true (20 years as a licensed API weld inspector).

Yes, it is the heat affected zone you worry about on a heat treated alloy mast. That could be a 50% loss, depending on the alloy and state of temper.

It's all about the quality of work and where the weld is located. Unless it was right at the mast base I'd walk away. There are lots of good used boats out there.
 
Feb 18, 2022
440
Catalina 36 Port Orchard
Yes... and no.

A full penetration butt weld is 100% strength in most codes, but a lap weld is 50%. Easily Googled. This feels counter intuative, but it is true (20 years as a licensed API weld inspector).

Yes, it is the heat affected zone you worry about on a heat treated alloy mast. That could be a 50% loss, depending on the alloy and state of temper.

It's all about the quality of work and where the weld is located. Unless it was right at the mast base I'd walk away. There are lots of good used boats out there.
My welding training and skills are mainly related to the automotive industry, and in that we are trained that a butt weld isn’t the way to go. We are taught to use a fishplate or sleeve and lap welds to perform repairs. Along with plug welds as well.

if I was stretching a frame or splicing it, I would have a butt weld at about 45 degree angle with a sleeve lap welded to the inside of the frame. This would restore the frame to full strength unlike with just the butt weld. This is as I have been trained and I myself have done while installing air ride and notching the rear of a frame for lowering a truck. As far as I know the truck is still on the road, though the new owner lived out of state so I have not seen it in a few years.

I agree if the weld is low (a foot or less) from the bottom you will prolly be ok, otherwise yes there are a lot of boats out there.
 
Mar 26, 2011
3,699
Corsair F-24 MK I Deale, MD
My welding training and skills are mainly related to the automotive industry, and in that we are trained that a butt weld isn’t the way to go. We are taught to use a fishplate or sleeve and lap welds to perform repairs. Along with plug welds as well.

if I was stretching a frame or splicing it, I would have a butt weld at about 45 degree angle with a sleeve lap welded to the inside of the frame. This would restore the frame to full strength unlike with just the butt weld. This is as I have been trained and I myself have done while installing air ride and notching the rear of a frame for lowering a truck. As far as I know the truck is still on the road, though the new owner lived out of state so I have not seen it in a few years.

I agree if the weld is low (a foot or less) from the bottom you will prolly be ok, otherwise yes there are a lot of boats out there.
Agreed... if a sleeve is used. it is not the lap weld that makes it stronger, it is the sleeve that compesates for the heat affected zone. Additionally, running full penetration welds in thin materials is devilishly difficult. The sleeve makes that easier by providing a heat sink.
 
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Mar 26, 2011
3,699
Corsair F-24 MK I Deale, MD
I've seen a good many welded around the base to repair corrosion or ice damamge. This is a low bending stress area. But up around the spreaders... I'd fit a new mast. It can be done, but it required pro work that probably didn't happen on a 19-foot boat.

On the other hand, if you're just sailing in the harbor, maybe you can live with the risk if it looks well done. You may also be able to find a mast on a similar small boat that is through it's lifespan. Look in the back corners of the bone yard and ask around.
 
May 24, 2004
7,164
CC 30 South Florida
If the weld was well done that mast may break at any other point but where that weld is. That is because a proper repair requires and insert piece which adds strength beyond what the weld gives.
 
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