Hobie Cat Forums

It is currently Fri Dec 19, 2014 7:22 am

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 9 posts ] 
Author Message
PostPosted: Mon Jun 07, 2010 8:11 am 
Offline
Site Rank - Captain

Joined: Thu May 03, 2007 2:28 pm
Posts: 31
Location: Chicago
Looking through the forums I haven't seen this addressed specifically. My main question is how many times can you safely repair a mast base (not step)?

Stepping the mast this weekend, it came loose for the 2nd time in 3 years. The rivets are intact - they shear through the bottom of the mast so the holes are now grooves. I had 2 rivets rip through the mast 3 years ago, so I drilled and installed 2 more (SS with top hats). Now I have 4 C-shaped holes in the bottom of my mast and 4 rivets sticking out of the mast base casting. If I drill and install more they will all be close together. As I recall you can't really drill workable holes through the front or back because of the thickness of the base casting. Buying a new mast is not an option. The base is fine, I think, except for the 4 rivets in it. I have not removed the base to really examine it yet.

If sawing off the bottom of the mast is the best option, how would I make sure that the bottom is flat and level?
Is my standing rigging not going to fit? Will the mast rake change? Would 1/2 - 1 inch make it noticeably harder to get under the boom on tacks?

Is there a good alternative to drilling holes and riveting?

How secure does the mast base need to be? I think most sailing pressure is straight down on the mast, right?

Why does this keep happening to me? I only step the mast once a year.

_________________
hullflyer


Top
 Profile  
 
PostPosted: Mon Jun 07, 2010 9:42 am 
Offline
Site Admin

Joined: Tue May 27, 2003 12:44 pm
Posts: 9306
Location: Oceanside, California
Quote:
Why does this keep happening to me? I only step the mast once a year.


The mast ball is likely over shooting the cup which stops its proper rotation. The mast continues to rotate up and that shears the rivets. You need a new step link and should watch the base as the mast is nearly vertical. Be sure it drops in the cup. Be sure the link is not stopping it either.

Once up... the pressure is down, so rivets are not needed for much.

_________________
Matt Miller
Director of Parts and Accessory Sales
Hobie Cat USA


Top
 Profile  
 
PostPosted: Wed Jun 09, 2010 10:57 am 
Offline
Site Rank - Captain

Joined: Thu May 03, 2007 2:28 pm
Posts: 31
Location: Chicago
mmiller wrote:
Once up... the pressure is down, so rivets are not needed for much.


So, the mast base rivets are reallly there mostly for stepping the mast and are not serving much function when sailing? If so, I will go ahead and just find 2 more places for holes and not worry about shaving off the bottom of the mast for a clean start. (I don't think a mast would buckle from perforations in the bottom 1").

Hey thanks for the diagnosis - I did notice that the base slipped along the step as we started raising the mast, but I thought that was because of the base coming loose not the other way around. I let another fellow put the pin in the step-aid and maybe he hit the wrong hole. Will be more careful next time.


Top
 Profile  
 
PostPosted: Wed Jun 09, 2010 1:33 pm 
Offline
Hobie Approved Guru

Joined: Mon Jul 14, 2003 7:11 pm
Posts: 4641
Location: Detroit, MI
The easiest way to get a clean straight cut around the mast is to take a piece of legal size paper, cut a strip narrow enough to fit between the jib turning block and the mast base. You'll end up with a ~3" x 14" strip. You don't need to be careful about the cut being straight.

Wrap the strip around the mast and line up the edges on the straight side (the side you didn't cut) at the aft end of the mast. Make sure the paper lies flat and mark the edge all around the mast with a pencil.

Use a hacksaw and follow the line (don't try to cut through the mast all at once). Save the web behind the sail track for last. A big file will smooth out the saw marks.


Top
 Profile  
 
PostPosted: Wed Jul 07, 2010 11:02 pm 
Offline
Site Rank - Captain

Joined: Mon Jun 07, 2004 7:20 pm
Posts: 59
Location: Shreveport, LA
If you have a chop saw or mitre saw, you can get non ferrous cutting blades for them. Nice clean cuts at a nearly perfect angle. I have done this repair after the base was ripped off my mast. After a small adjustment in the standing rigging, I never noticed.

_________________
Why did I sell my 16?


Top
 Profile  
 
PostPosted: Sun Jul 11, 2010 3:39 pm 
Offline
Site Rank - Captain

Joined: Sun Jun 27, 2010 12:23 pm
Posts: 45
Location: Brooklyn, NY
hi.
I tore the mast off the base of my '81 H16 this morning. It was my first time stepping the mast and I was having difficulty before this happened, but I finally got it near vertical. And then the mast came off the base. It was all a bit scary and out-of-control.
The base actually tore. The rivets stayed in the mast. It looks like there aren't any more good spots for rivets in the end of the mast because it looks like this happened to the previous owner(s). The base has 4 torn holes too.

So my plan is to:
a.) cut 3/4" off the bottom on my mast
b.) buy a new base and a stepping link(I was borrowing one)
c.) drill and 4 new SS rivets

My questions:
1.) Is this a good plan?
2.) it looks like there is a flotation bag in the mast, can I just push it further up into the mast, out of the way of my new cut?
3.) While the mast was down, I noticed a small corrosion hole about 4" from the bottom. Is that a potential new concern?
4.) There is a H16 mast for sale in my area for $200. This seems like a simpler/cheaper solution. Will most used mast have these issues?

thanks in advanced,
momentarily boatless,
frank


Image

_________________
frank pichel, H16 Veribold, #71146


Top
 Profile  
 
PostPosted: Fri Jul 16, 2010 5:46 am 
Offline
Site Rank - Captain

Joined: Wed Jun 30, 2010 2:24 pm
Posts: 112
Location: Todd Mission, Texas
I would drill out those rivets. Then clean out the remnants of the mast base. Get a new mast base and match drill and rerivet. The holes with the rivets in them should be OK.

_________________
Jeff
1986 Hobie 18 #13031


Top
 Profile  
 
PostPosted: Wed Jul 21, 2010 11:06 am 
Offline
Site Rank - Old Salt

Joined: Mon May 24, 2004 10:33 am
Posts: 434
Location: Clinton, Mississippi
fpichel wrote:

My questions:
1.) Is this a good plan?
2.) it looks like there is a flotation bag in the mast, can I just push it further up into the mast, out of the way of my new cut?
3.) While the mast was down, I noticed a small corrosion hole about 4" from the bottom. Is that a potential new concern?
4.) There is a H16 mast for sale in my area for $200. This seems like a simpler/cheaper solution. Will most used mast have these issues?


I would also try to avoid cutting the mast if at all possible. I don't know about a "floatation bag", but there should be a foam plug up there. Make sure it's securely in position and well-sealed while the base is off. I wouldn't worry too much about the small hole, but it sounds like a good idea to get that other mast as a spare if you've got the dough and a place to store it.

_________________
Jerome Vaughan
Hobie 16


Top
 Profile  
 
PostPosted: Wed Jul 28, 2010 7:55 pm 
Offline
Site Rank - Captain

Joined: Sun Jun 27, 2010 12:23 pm
Posts: 45
Location: Brooklyn, NY
Hello all

thanks for all the help and tips. The bottom of the mast had a lot of holes from a previous owner's re-riveting, and I don't think it was serviceable again.
If I had a method of moving a new(used) mast a 100 miles I probably would have bought one, but I don't have a trailer.

I ended up cutting an inch off the mast and riveting on a new base. It seems to be working great. Been out three times since, and all is good.

The 'bag' I saw inside the mast was some kind of seal at the bottom of the foam - don't know if it was stock or a repair. I left the foam in place.

Thanks again for all the answers, I couldn't have done it without the forum.

frank

_________________
frank pichel, H16 Veribold, #71146


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group