Mast repair options

[Endeavour35.5]

https://www.permatex.com/products/ad...ding-compound/

As a spar builder we use epoxy on the doubler sleeve and fastenen it with 1/4” alum. rivets

[Shoalcove]

As a fellow Canadian, I’m not sure what that has to do with anything. Wouldn’t your insurance company be the ones to sue the marina for the recovery of costs if they were at fault?
As far as repairs go, there seems to be some debate. The difference between having a mast builder repairing the damage and you cobbling something together may be profound if the mast fails in the future and someone/something gets hurt.
I have just gone through the process of replacing a damaged mast. My insurance company and I were not willing to have anyone but professionals do the work. Besides issues of liability, there is the question of resale and the ability to pass a future survey for insurance purposes. My 2cents...

[GordMay]

I’d seek advice from:
SPARCRAFT-US (Charleston Spar)
3901 Pine Grove Circle
CHARLOTTE NC 28206 USA
Phone: (1) 704 597 1502
Fax: (1) 704 597 0961
E-mail: sales-us@sparcraft.com

[chris95040]

You are afraid to use insurance for exactly the sort of thing you use insurance for.

You are afraid to use a sleeve for exactly the sort of thing you use a sleeve for.

Ok, so you want a technical, innovative, elegant solution.. but nothing with a whiff of standard practice..... I’ve got it! Build a time machine, go back to before the accident and prop your boat up correctly!!

Let me guess, did you avoid jack stands because you were afraid they wouldn’t like it under the boat? [emoji23]

[jimbunyard]

Unless their is some additional damage outside the picture, the main structural integrity of the mast remains; the ripped hole is only about 4 times larger than the original hole. It is surprising that the aluminum could be ripped so severely with only the holding power of 2 rivets, certainly says something about the security of riveting properly done.

Given the remaining structural integrity, and the small loss of same, the idea of 'cutting the mast in half and sleeving it' is at best silly.

Get an opinion of a reputable mast repairer (not necessarily a mast builder), and see what they say. Don't be afraid to get a second or third opinion and of using the information gained to make your own decision.

If it were me, I'd use heat to form the existing metal back into its original position and weld the joints after 'v-ing' it out, with backing gas and/or a backing plate.

If the bent piece cracks when reforming it, I'd go ahead and break it out, try and flatten it and reuse it, but if that is not possible, I would try and duplicate the alloy, cut the hole to an easily matched configuration and 'grave in' the new piece by welding, again with backing plate and/or backing gas.

If you don't want to weld, you could cut the distorted piece out, put a backing plate in that extends 6 - 8 inches beyond the hole, rivet that to the interior of the mast and then rivet the spreader base through both the existing mast and the new plate. Providing you have room inside the mast of course...

[Elie]

[QUOTE=Seaslug Caravan;2765922][QUOTE=Elie;2765509]My sailboat fell off its cradle and the mast was damaged.



Elie, its fixable.

You are on the right track with the doubling plates held with metal threads.

Drilling the holes to stop further cracking is a good start.

Metal needs to be restored under the spreader compression post . If the small amount of bent metal can't be worked back into shape then cut away the minimum amount necessary before sandwiching in new metal. Most of the repair will be covered by the spreader base. You may need to shorten up the spreader a tad to allow for the plate thickness.

Don't be too concerned with the temper of the repair metal. Its such a small area and oversizing the thickness slightly will cover any weakness.

Good luck.

PS . I've worked on Alloy spars where we have cut holes big enough to get your hands through to make internal repairs and the rigs are still going strong after many years of hard racing.

Be brave, use common sense and ignore the ignorant goons.[/QUOTE

Thank you very much. That was the right type of answer for the technical problem that I submited in this thread. The other legal and insurance stuff is not part of my wory for now and further, I do know how to deal with it!

To go in the direction of what you proposed, I have allready started to pull out the bent part. Slowly, with a puller and it seems to work. But the terrible fall we have here Upstate NY, (Cold, snow, etc.) stoped my work. I believe that I will be able to pull back de bent metal, and I'm musing with the idea of have the cracks brazed back in place, by an expert welder. Brazing requires much less heat then TiG or MiG welding, and therefore, won't affect the temper of the mast section on a large area(At least that is what I read). Naturally, inside and outside formed plates of tempered aluminum is mandatory. I would install plates on both side of the mast to keep things 'balanced'. I found that very powerfull polyurethanes glues can be used along with monel rivets and bolts to seriously attach the plates to the skin of the mast. After all, airplanes wings are now using this type of glue with much success.

[Dymaxion]

You can soften the bent bits with a propane torch, but beware that aluminium melts very suddenly with little warning. You weld aluminium not braze it. Read up a bit on welding techniques. You can spot weld it every inch or so first pass, then repeat process until you have a full bead. This will control warping but you are still affecting the temper. Welding affects fatigue life, and will create crack initiation. Technically aluminium never has an infinite fatigue life, like steel. But if you get 5 years out of the weld maybe that's a good enough deal.
Ignoring the immediate insurance issues, if your repair fails later and you lose the entire rig, it won't be the boat yards fault, will it?

[Elie]

I strongly believe that it is fixable, and a well done repair will not affect the solidity of the mast, nor its performance. My mast is close to the Canadian border, very far away from any serious rigging expert shop. That create a problem!. I have been in touch with Charleston Spars, to buy a new complete extrusion but I'm quite disapointed by the lack of formal response from them. Speaking with a certain mister Green, but no follow up, beyond nice talk!. And by the way, they agree that in any way, the mast can be repaired, and they say that they have the extrusion plate. But they never took formal action! for my request. Disturbing!. Maybe shall I call someone higher or in France, the mother compagny?...

[AKA-None]

Originally Posted by GordMay

I’d seek advice from:
SPARCRAFT-US (Charleston Spar)
3901 Pine Grove Circle
CHARLOTTE NC 28206 USA
Phone: (1) 704 597 1502
Fax: (1) 704 597 0961
E-mail: sales-us@sparcraft.com

This is your best first place to start

[Elie]

Originally Posted by AKA-None

This is your best first place to start

I've done that. They agree with the repair option. But I've asked then for a price and a delivery date, and I'm still wayting for a real answer. I wonder if they are too busy, not interested or simply that the salesman is simply negligent!.

[Fiveslide]

Originally Posted by Elie

I've done that. They agree with the repair option. But I've asked then for a price and a delivery date, and I'm still wayting for a real answer. I wonder if they are too busy, not interested or simply that the salesman is simply negligent!.

You have to bug the crap out of these spar suppliers. I was told by one they didn't have what I needed, but the spar cross section I wanted was in their catalog, still couldn't get them to sell me one. Finally found a used rig that fit my needs so I didn't have to pursue it further. Bug that salesman, then ask for another salesman until you get answers from someone.

[chris95040]

Originally Posted by jimbunyard

Unless their is some additional damage outside the picture, the main structural integrity of the mast remains.

Yeah? To me it looks like almost a whole side of the mast is missing.

Originally Posted by jimbunyard

It is surprising that the aluminum could be ripped so severely with only the holding power of 2 rivets, certainly says something about the security of riveting properly done.

If I understood correctly, the damage occurred from the spreader compressing and crushing the mast. Don’t think you can infer much about fastener strength from that.

Originally Posted by Elie

The other legal and insurance stuff is not part of my wory for now and further, I do know how to deal with it!

Yeah, good point. But if you didn’t get 1000 answers to questions you didn’t ask and almost none to the one you did, it wouldn’t be cruisers forum!

[jimbunyard]

Originally Posted by chris95040

Yeah? To me it looks like almost a whole side of the mast is missing.

If I understood correctly, the damage occurred from the spreader compressing and crushing the mast. Don’t think you can infer much about fastener strength from that.

Yeah? Well you must be looking at a different picture.



Generously, the damaged area appears to be about 5" x 5", so say about 25 sq in. Assuming a 60 foot mast on a 47 foot boat, that's 720 inches times about 8 inches (the width of the side), so that's 25 square inches out of 5760. Or (I think) about .44 % of the 'whole side'.

Unless the crack on the 'lower' side (under the 2 on the tape) goes around the corner to the perpendicular face of the mast, virtually none of the structural integrity of the mast has been compromised. If it were not for the need to have something to anchor the spreader base, and other, cosmetic reasons, the broken piece could be cut out with rounded corners and the mast used as is.

Though you may not see the relevance...






Just because you can't infer much about fastener strength from an analysis of the OP's picture doesn't mean I or others can't...

[valhalla360]

Originally Posted by jimbunyard

Yeah? Well you must be looking at a different picture.



Generously, the damaged area appears to be about 5" x 5", so say about 25 sq in. Assuming a 60 foot mast on a 47 foot boat, that's 720 inches times about 8 inches (the width of the side), so that's 25 square inches out of 5760. Or (I think) about .44 % of the 'whole side'.

Unless the crack on the 'lower' side (under the 2 on the tape) goes around the corner to the perpendicular face of the mast, virtually none of the structural integrity of the mast has been compromised. If it were not for the need to have something to anchor the spreader base, and other, cosmetic reasons, the broken piece could be cut out with rounded corners and the mast used as is.

Though you may not see the relevance...






Just because you can't infer much about fastener strength from an analysis of the OP's picture doesn't mean I or others can't...

Just enough knowledge to be dangerous apparently.

Different parts of the mast are under different levels of stress. At the spreader base is one of the most stressed areas, so if the circumference (not the whole length) is half gone, it's lost a lot of strength (likely upwards of 75%).

In your example pictures you miss the point that those structures are not stressing the areas that have holes.

Yes, it's repairable but this is massive damage until it's repaired.

[jimbunyard]

Originally Posted by valhalla360

Just enough knowledge to be dangerous apparently.

Different parts of the mast are under different levels of stress. At the spreader base is one of the most stressed areas, so if the circumference (not the whole length) is half gone, it's lost a lot of strength (likely upwards of 75%).

In your example pictures you miss the point that those structures are not stressing the areas that have holes.

Yes, it's repairable but this is massive damage until it's repaired.

Don't think I'm the one who's missing the point, as a careful consideration of the relation between the web of an I-beam and its' upper and lower flanges as analogous to the relation between the faces of a rectangular tube. Or perhaps you missed the 3.5" x 1.5" holes on either side of the 'wide' dimension of the rectangular aluminum tube (mast) that would tend to disprove the point you seem to be trying to make.

Perhaps you also missed "If it were not for the need to have something to anchor the spreader base" from my post.

If the mast had no stays or spreaders, it would just be a flagpole; the stayed mast acts as a complete system to support sail loads, one can't eliminate one part and expect the system to be functional.

Would be interesting to find where your 75% number comes from...and if it refers to the mast by itself or in combination with its supporting structures.