Hobie Forums
http://www.hobie.com/forums/

Cracked mast
http://www.hobie.com/forums/viewtopic.php?f=14&t=48491
Page 1 of 2

Author:  ricke314 [ Mon Jul 15, 2013 7:34 pm ]
Post subject:  Cracked mast

I just bought my first boat, a 1980's Hobie 16. In the process of cleaning everything up (and, unfortunately, not when I initially inspected the boat before purchase), I noticed that there is a crack in the mast along side the sail feeder. It extends below the feeder opening. You can see the extent of the crack in these pictures:

http://imgur.com/a/Zu9wp

Is this something that can be repaired? How serious is the issue? I've tried to search for similar issues, but haven't come across much.

Author:  GD_NC [ Tue Jul 16, 2013 5:17 pm ]
Post subject:  Re: Cracked mast

Yikes, I'd start hunting for a new mast. That looks pretty dangerous.

Put a post up in the "looking to buy" section here and someone can probably help you locate one in your area. Be sure to include your location.

Author:  Rab1515 [ Tue Jul 16, 2013 5:48 pm ]
Post subject:  Re: Cracked mast

I'm not sure if the crack is in a place that is structural. It looks like from the pictures that the crack is in the mast track below the slot, which would not be structural. correct me if I'm wrong, but if the crack would weaken the mast wouldn't the mast slot weaken the mast as well? if you really want to replace it i have a comtip mast currently for sale in MD.

Author:  ricke314 [ Tue Jul 16, 2013 6:31 pm ]
Post subject:  Re: Cracked mast

As I understand it, the mast cross section on the Hobie 16 looks something thing this:

Image

I marked in red what I'm guessing is the break point: right behind the luff track. It seems to be a weaker point. My concern is partly for the vertical integrity of the mast, but more specifically, for the horizontal integrity. The crack is right about where the gooseneck shackle for the boom would rest with the downhaul marginally tight. I'm guessing that's handling a decent amount of the force of the sail directly at that location. It's possible the previous owner sailed it like this for years and never had an issue, but I'm trying to assess the urgency of the repair.

I've contacted my local sail shop this afternoon, and they have suggested that they do Heliarc (TIG) welding, and might be able to repair it, but will need to see it first. Has anyone had any experience with having a mast repaired via this method?

Failing that, I'll be looking for a used Hobie 16 mast. GD_NC, thanks for the suggestion on the "Looking to buy" section. I'll check it out, if it comes to that. Rab1516, I'm in the greater Detroit area, so MD would be a bit of a haul, unfortunately.

Author:  sunvista [ Wed Jul 17, 2013 5:41 am ]
Post subject:  Re: Cracked mast

Why not just take it somewhere and have it TIG or MIG welded? I don't think I would attempt to sail with a crack that long.

Author:  AntonLargiader [ Wed Jul 17, 2013 6:57 am ]
Post subject:  Re: Cracked mast

If the crack were only through the track, I think it would be easy to tell because that flange would flex very easily.

I'm wondering if water froze in that section of mast somehow. Maybe the mast leaks, water pooled on top of the foam plug and then froze during the winter.

Author:  mdgann [ Wed Jul 17, 2013 8:28 am ]
Post subject:  Re: Cracked mast

Welding an aluminum extrusion is never a good idea. Maybe better than not sailing, but you completely change the material properties in a small area and that spikes the loading in the area so you will get further cracking and damage. Anyone know the alloy and heat treatment of the Hobie mast? In aircraft damage repair you would replace the part or if that is not possible do a doubler repair that would replace 100% of the strength to the area. That would imply that you know the loads in the area and that you could put enough fasteners in the doubler to carry the load in shear. Also possibly stop drill the crack at both ends.
There is no area of the mast that is not structural. Even the track adds quite a bit of stiffness to the entire extrusion.

Author:  mdgann [ Wed Jul 17, 2013 8:33 am ]
Post subject:  Re: Cracked mast

After looking at the pictures, a doubler is not a possibility. I would start looking for a mast.

Author:  PurdueZach [ Wed Jul 17, 2013 9:23 am ]
Post subject:  Re: Cracked mast

Keep an eye out for a replacement mast. They aren't too hard to find on an old beat up boat.

Author:  ricke314 [ Wed Jul 17, 2013 9:58 am ]
Post subject:  Re: Cracked mast

mdgann, thanks for the input on the welding. I was worried about the same thing. If the price is right, I may have it welded to at least get on the water (we have a vacation planned in a couple of weeks and it would be a real shame not to get to sail it), and then start searching for a replacement mast in the area.

AntonLargiader, the freezing concept is an interesting one. The mast (even excluding the crack) is definitely not watertight yet. One of the cleats is gone, and so there are a couple of open rivet holes at the base. I'm also guessing I need to re-seal the tip (assuming I keep the mast) and possibly base.

Author:  sunvista [ Wed Jul 17, 2013 10:14 am ]
Post subject:  Re: Cracked mast

My first H16 had a cracked mast at the top where the comp tip inserted. I had it welded and sailed it for five years before I found another mast. I kept the welded mast just in case. A friend of mine lost his mast in a hurricane so I traded him the welded one for a favor he had done. That was six years ago and it is still in use. Maybe it doesn't meet FAA air frame standards....but who cares?

Author:  AntonLargiader [ Wed Jul 17, 2013 10:23 am ]
Post subject:  Re: Cracked mast

I sailed my '78 with a broken/rewelded mast from the time I bought it in '93 through this year.

Author:  ricke314 [ Wed Jul 17, 2013 1:26 pm ]
Post subject:  Re: Cracked mast

It's good to hear that people have had successful experiences sailing with welded masts. A weld job is a much smaller obstacle preventing me from getting the boat on the water for the first time than finding a new mast would be.

Author:  jsloan999 [ Wed Jul 17, 2013 2:43 pm ]
Post subject:  Re: Cracked mast

I have a good mast and the price is right (Free). The only problem is that you have to pick it up in Los Angeles.

I also have a good H16 tramp frame (Free). Same deal on the pickup.

Author:  GD_NC [ Wed Jul 17, 2013 4:49 pm ]
Post subject:  Re: Cracked mast

I wouldn't give up on a replacement mast yet. Hobie 16 masts tend to far outlast the hulls and there's not much demand for the old ones. If you live near a decent sized body of water you can probably find one without much effort. Most hobiecat sailors are more interested in seeing a new hobie sailor on the water than making a buck off you. (See post above)

Page 1 of 2 All times are UTC - 8 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/