Repairing a snapped mast

[dogeconomics]

Working on restoring a 16' racer (no idea what she is... probably a custom build). When I removed a fiberglass sheath covering the mast joint, it snapped right in half. Water got trapped behind it and rotted out the joint. So, I'm looking for advice on how best to proceed. My idea is to cut off the rough ends, losing about 4" from mast height, drill out the (snapped) joining piece, and replace it with some white oak (pictured). Anyone have a better idea? Or general advice?

Overall mast height: ~26'
Top section: ~14'6"
Bottom section: ~11'

Pretty sure it's a mast straight off a Hampton One with an extra set of shrouds. At least, the sail has the Hampton One sigil on it.

Thank you!

IMG_7716.jpgIMG_7713.jpgIMG_7714.jpgIMG_7715.jpg

[stromborg]

Re: Repairing a snapped mast

Take a look at the pictures in this thread:http://forum.woodenboat.com/showthre...othespin-scarf

Clothespin type scarf in both directions, keeps the mast at the built length. Shortening it might well lead to more work as you also then have to adjust shroud lengths and maybe how the boom/mainsail attach to the mast.

[dogeconomics]

Re: Repairing a snapped mast

Ok awesome, thanks!

I'm replacing the shrouds anyway, already have the new material ready to go.

[Canoeyawl]

Re: Repairing a snapped mast

White oak is not noted for it's gluing properties.
I would scarf in some Doug Fir.
12:1 scarfs, clothespin or not.

[willin woodworks]

Re: Repairing a snapped mast

Build a new one. Spruce, doug fir...

[Yeadon]

Re: Repairing a snapped mast

Make a new mast. Great project. You have the perfect template right in front of you. White oak wouldn't be a material that I'd choose for this, btw.

[dogeconomics]

Re: Repairing a snapped mast

I'm not opposed to building a new one... next winter. I've spent the past 8 months restoring this boat and really, really want to get on the water. I'll do another round of refit over the winter, including finishing out the cockpit, systems, and any rigging fixes/adjustments. Maybe new sails. Long term, this project is a learning experience for building my own.

Right now... just want to go sailing!

[nrs5000]

Re: Repairing a snapped mast

Agree white oak is not the right stuff for the repair, between poor gluing properties and weight. Also it's quite different in strength and other properties from what's already there, I wonder if that could lead to problems in the nature of stress concentration. Replacing the problem area with a clothspin scarf is good advice.

It looks like the mast has already been repaired in that area once. Whether you try to make a long term repair on this spar or build a new one, is there anything else about why the mast failed here, beyond the fiberglassing you removed?

[dogeconomics]

Re: Repairing a snapped mast

Agree white oak is not the right stuff for the repair, between poor gluing properties and weight. Also it's quite different in strength and other properties from what's already there, I wonder if that could lead to problems in the nature of stress concentration. Replacing the problem area with a clothspin scarf is good advice.

It looks like the mast has already been repaired in that area once. Whether you try to make a long term repair on this spar or build a new one, is there anything else about why the mast failed here, beyond the fiberglassing you removed?

Not that I can see. Pretty sure it was built in two sections and joined with just that thin strip (~1/2") of wood. What would be an ideal scarf wood?

I'm trying to keep this as simple as possible right now. I've faired the hull, rebedded all the hardware, replaced 8 frames, bilge painted, installed new rubrails, fabricated a new steel centerboard... this is the last major hurdle. Just want to get on the water.

Before picture:

IMG_6968.jpg

[Canoeyawl]

Re: Repairing a snapped mast

What would be an ideal scarf wood?

Doug Fir or Home Depot spruce would be just fine

(That 1/2 tenon won't work, and never would have worked)

[wizbang 13]

Re: Repairing a snapped mast

This mast has already been a victim of a junky repair.
That thing in the middle there is not how the mast was built

[Yeadon]

Re: Repairing a snapped mast

From here, I'd say that's a pretty basic mast. Not hollow. Not a box. It's basically a slab of meat with radius'd corners. You'd end up scarfing material to get your length, but that's great practice. Maybe there's a track screwed to one side? If the spreaders are good then they're already made. Having the old spar right there and available as a template (plus the fittings on it) you're way ahead of the game.

Anyways, it's not a vote but that's my vote.

[dogeconomics]

Re: Repairing a snapped mast

Yeah, a slab of meat. It is hollow in other parts of the mast, I know from some epoxy work. And yeah, it has a bronze track.

So I guess I'll find some fur, a good YouTube video, and get to it this weekend. Any other suggestions??

Here's the back side of that joint:

Photo May 24 2023, 16 21 02.jpg

[Autonomous]

Re: Repairing a snapped mast

So I guess I'll find some fur...

Fur, or baggywrinkle?

2830_646231_2887807507171ffc46ba21c568acd250.jpg

[hawkeye54]

Re: Repairing a snapped mast

Doge - If I'm looking at the mast join correctly, it appears that the previous owner may have routered in a groove in one face of the mast and glued in a spline , then turned over the mast and routered in two grooves in the other face of the mast and glued in two more splines. As others have mentioned, it may be best to craft a replacement mast .




Rick