Mast Crack Repair?

[PutASailOnIt]

Well, while trying to replace my old cast aluminum spreader brackets with SS ones I discovered that the lower bolt seized to the compression tube inside the mast. I didn't know that's what had happened until I tried to move the bolt out with a hammer and obviously too much force. You can see the end result in the pictures, does anyone have advice on the best way to repair this short of replacing the whole mast extrusion?

This in on a 1980 Catalina 25 short rig

Thanks a ton!

[zeehag]

sleeve n weld. friend in mazatlan did that

[Tscott8201]

A good TIG welder could probably do it. The key will be limiting heat input so as to not weaken the surrounding aluminum. Also not having access to the back side of the crick may cause issues with contaminating the weld. As mentioned above, you could place a sleeve over the cracked area and have that welded. The sleeve method would eliminate the contamination issue but the heat from the weld could weaken the mast. If you sleeved it and did plug welds instead of welding the perimeter of the sleeve then you would lessen the chance of heat affecting the temper all the way around the mast but then crevice corrosion becomes an issue. Personally I'd probably lean towards finding a replacement mast but if that's not practical then I'd sleeve it and hire a good reputable welder.

Tom

[HappyMdRSailor]

Wowza that sucks....

DON'T weld it... You'll only induce more probable weaknesses... Make a rectangular plate bent to the side curvature out of Al... Slightly thicker than the mast... I'd overlap the crack ends by 4-6"... Drill a hole at the crack ends to stop propagation, and stagger your attachment fasteners so they aren't all in straight lines...

[chris mac]

A friend of mine has a Catalina 25, cracked his mast last year. He hired someone to weld it( someone with a lot of aluminum exp.) when we pulled this fall the weld looked good. We pushed it pretty hard through the summer so it looks like it's fixed, but I think the key is an experienced welder. As mentioned above too much heat will cause weakness in the aluminum.

[Hamish_ct]

My experience with cracks in the mast is that no repair will be 100%. Your repair, sleeve or collar will fail and it will be catastrophic. It may not be in the first 2 to 5 yrs but then it will happen. Although on my J I have never had that happen but on the lasers we sail a mast crack always means a new mast. Happens a lot on a laser. The pressure on the mast in strong weather when you need it most is when this will happen.

Imo. Its worth it to look for a used mast or a new one. The consequences are that someone will get hurt when the weather gets bad.

Good luck and fair winds.

[cal40john]

Originally Posted by Hamish_ct

My experience with cracks in the mast is that no repair will be 100%. Your repair, sleeve or collar will fail and it will be catastrophic. It may not be in the first 2 to 5 yrs but then it will happen. Although on my J I have never had that happen but on the lasers we sail a mast crack always means a new mast. Happens a lot on a laser. The pressure on the mast in strong weather when you need it most is when this will happen.

Imo. Its worth it to look for a used mast or a new one. The consequences are that someone will get hurt when the weather gets bad.

Good luck and fair winds.

I think you have a poor comparison. A free standing dinghy mast that bends significantly is being compared to a mast headed rig with fore and aft lowers.

[Jim Cate]

Originally Posted by cal40john

I think you have a poor comparison. A free standing dinghy mast that bends significantly is being compared to a mast headed rig with fore and aft lowers.

I quite agree with this, John! And for Hamish, lots of masts come from the factory with sleeved joins in them, and they don't automatically fail. A well done repair can be quite satisfactory.

Jim

[eastanglian]

Here is a repair of a broken 2.4mR sailboat mast, but the principle applies to any aluminum mast. Cut mast halfway along crack. Find a similar mast section which can be trimmed to use as an internal sleeve at least as long as the crack. Have the crack welded by a professional.



https://youtu.be/2O6r1bx6aZA