SailNet Community - Reply to Topic
Thread: repairing dent on the mast Reply to Thread
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

  Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below

  Topic Review (Newest First)
10-21-2013 03:03 PM
Re: repairing dent on the mast

Alex_W: Yes it is an Isomat mast. Not sure what happened. Went sailing on a high wind day 18-20 with 30 gusts. Coming back into the marina and one of the crew points up and goes "is that supposed to be bent back like that?"

The manufacturer and surveyor say it may have been a defect in the weld that just finally failed 19 years later.
10-20-2013 11:56 AM
Alex W
Re: repairing dent on the mast

mmazour: What is the story on that spreader seperation? The photo is overexposed, but it looks like that could be an Isomat mast, which is what my Pearson has.
10-19-2013 11:10 AM
Re: repairing dent on the mast

Find out who the mast manufacturer is and get their opinion. What brand of boat is it? Do you know what brand of mast it is?

Alex_W is correct aluminum does not like to be worked and can/will fatigue easily. If that mast breaks and comes down you will be spending money on a lot more that just a mast; all rigging (running and standing), sails, roller furling, fiberglass repairs, hospital bills, higher insurance premiums, etc.

You do not want to wind up with this:
Attachment 16017
10-19-2013 10:08 AM
Alex W
Re: repairing dent on the mast

Aluminum doesn't like to be bent and bent back. It fatigue cracks very easily. That method will make it look nicer, but isn't going to return it to it's original strength and may make it weaker than it currently is.

The plate that bridges this sounds like a better solution to me. Talk to another rigger and see if you get the same advice.
10-18-2013 09:59 PM
Re: repairing dent on the mast

Thanks for the clarifications! I'll try that method.
10-18-2013 09:33 PM
Re: repairing dent on the mast

I use the mandrel to hammer against the same way you would do car body work. the mandrel need to fit the contour of the inside of the mast but not to tight . only needs to fit tight where the dent is. I used a long 2x4 to push the mandrel into the mast. taped it in until it hit the dent. had another person tap it in as you tap on the outside of the dent. it is combination of both the mandrel pushing it out and the hammering on the outside. that moves the metal. first one I used very hard wood with the grain going across the mast. the second one we used a mandrel made out of Delrin plastic. and we left the Delrin in the mast as a spreader. that mast did not have internal halyards or any wiring
10-18-2013 05:31 PM
Re: repairing dent on the mast

Originally Posted by overbored View Post
I would straighten that one of two ways. make hardwood end grain mandrel and slide it into the mast. while someone pushes it down or up past the dent you would tap the outside with a body hammer.
Hello overbored. I'm thinking of straightening the dent. I'm not sure I understood your method. What is the purpose of the mandrel? Is it just to support the mast wall while tapping directly above it? Or should it be a tight fit inside the mast, and pushing it under the dent would push the dent upwards?
10-15-2013 05:12 PM
Re: repairing dent on the mast

Thanks everybody for the answers.

bassmanss: ouch, sorry to hear that! I still have hope that I can salvage this one. I don't have money to buy another one right now, probably even a used one (I'm buying new standing rigging as well, not cheap).

I'll keep an eye out for bargains though, who knows.

I'm having the rigger build a bigger base as well as a support which braces the mast. Regarding the compression fitting, it's a great idea, I'll look into it. Should it be made of aluminum or stainless steel?

overbored, you mention an interesting technique for removing the dent. I didn't think it was doable until now. I'll look into it.
10-15-2013 01:46 AM
Re: repairing dent on the mast

I would straighten that one of two ways. make hardwood end grain mandrel and slide it into the mast. while someone pushes it down or up past the dent you would tap the outside with a body hammer. I have done this a few times and it is the best way. the other more redneck way would be to tap the dent out from the opposite side with a punch thru the existing holes. then I would install a larger spreader place bent to match the curve of the mast. also add a spreader bar between the plates. it is an easy one to fix
10-15-2013 01:15 AM
desert rat
Re: repairing dent on the mast

Bummer, as long as it lasts good, as much as you can do to make it last longer fine, but irreversible damage. Start looking for a used or new replacement NOW.
This thread has more than 10 replies. Click here to review the whole thread.

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

For the best viewing experience please update your browser to Google Chrome