Mast step crack

John Stahl · Post by **John Stahl** » Mon Dec 06, 2010 3:23 pm

This has me worried.
What was the cause and how would you fix it?

http://s1082.photobucket.com/albums/j37 ... %20repair/

hp18carr · Post by **hp18carr** » Mon Dec 06, 2010 5:31 pm

John

E.E. had some major damage done to his mast step once upon a time. Touch base with him for good advice concerning the repair. I'm no expert on any of this, but could having so much hardware installed that close to the mast step weaken the surrounding structure?

Terrence
Wilmington N.C.
Chrysler 26' 1980
Pandora (for now)

EmergencyExit · Post by **EmergencyExit** » Mon Dec 06, 2010 6:03 pm

Mine was self inflicted ! Wasn't paying attention stepping the mast, and the hook got in a bind. Threw the mast step within a few feet of the lake !!!Album of pics are here.

http://s591.photobucket.com/albums/ss35 ... %20Damage/

I was able to refill the center with ply and resin and wrap a binding around the outside to pull it all back into form. I'd sure take those screws out, lift the step and see what's under there.

Banshi · Post by **Banshi** » Mon Dec 06, 2010 7:35 pm

Kind of looks like a demasting perhaps lost shrouds or maybe while stepping the mast a bridle broke and it swung off to the side to far. I would rough it up and rap it in a few layers of glass. Good thing is, the loads when sailing are vertical.

Alanhod · Post by **Alanhod** » Mon Dec 06, 2010 11:45 pm

John Stahl · Post by **John Stahl** » Tue Dec 07, 2010 12:12 am

Dang I never thought about the water getting in around the hook.
I will take the hook off and have a look see.
Having the hook off will make it easy to repair the step.
I sure hope I don't have to replace the wood support that is under the hook.

I have some great ideas of how I want to personalize the boat but they keep getting put off tell I have the refit done.

sauerleigh · Post by **sauerleigh** » Tue Dec 07, 2010 4:06 am

You might consider adding a mast step plate after you repair the step. I have this on my half a CAT 25 and it works well and I'll be adding one to the Maude Kay. All the holes through the deck around the step are a source of leaks, and also the blocks are pulling the deck up against the mast stressing the deck in that area.
http://www.sealsspars.com/maststepcatalog.html

CaptainScott · Post by **CaptainScott** » Tue Dec 07, 2010 6:19 am

I"d also seriously consider a mast step hinge.
There are a lot of folks who are just fine without one but I love the way mine is set up and the ease of use.

Here is the original style hook:

Here is my new mast step hinge:

Just a thought . . .

Scott

John Stahl · Post by **John Stahl** » Tue Dec 07, 2010 8:24 am

Oooo I like it!
I really like the mast plate idea. I want to redo the foredeck and having all that hardware out of the way will really clean the new deck up.

Scot
The hinge has real merit.
How long have you used a hinge?

CaptainScott · Post by **CaptainScott** » Tue Dec 07, 2010 10:03 am

My 1975 Chrysler 22 came with it, my 1976 Chrysler 22 did not come with one and I promptly installed one. Stepped the mast without the hinge once. Did not like it one bit. I like the added security.

I've had the C22 for a few years now.

Scott

Jmckamey · Post by **Jmckamey** » Tue Dec 07, 2010 10:57 am

I'm thinking a mast stepping mishap as well. I should think there's a wood block under the step that we see, that would inturn be supported by the compression post in the cabin. Don't think is is as bad as it looks. Most likely have to cut off the cap, make a replacement wood block, grind down some of the glass then bond it all back together with fiberglass resin and some cloth to retain the surface strength. After you lay up the repair use a little wax paper and smooth it out using a bondo squeegee for a smooth finish. Might think about making some sorta jig to insure the top of the step is in the same place when you are finished. Good luck.

EmergencyExit · Post by **EmergencyExit** » Tue Dec 07, 2010 1:23 pm

Under EE's plate was a whole lot of pure green resin, no fill or chopped mat at all, then a piece of ply at the bottom. The screws barely made it into the ply much !

I almost thru bolted the plate,but decided I'd rather have the plate rip out the same way as opposed to being so solidly thru bolted to rip a chunk of the roof out should it happen again.

mariner · Post by **mariner** » Tue Dec 07, 2010 6:56 pm

Check out the hinged mast step at corsair marine, looks like the best I've ever seen, if I were to go through the trouble of making a hinged step I would model it after this one.

Jmckamey · Post by **Jmckamey** » Wed Dec 08, 2010 5:15 am

Well, if there's nothing but glass resin under the step then your only looking at a surface repair.

You know, you have to think these boats have survived a lot longer than the disgners intended.

John Stahl · Post by **John Stahl** » Wed Dec 08, 2010 8:43 pm

J. Austin · Post by **J. Austin** » Wed Dec 08, 2010 10:56 pm

I know that took some time in paint.
I've seen way crappier drawings in Catia.
Nice job.

sauerleigh · Post by **sauerleigh** » Thu Dec 09, 2010 5:16 am

Nice drawing, a fab shop worth its salt should understand it.

LeatherneckPA · Post by **LeatherneckPA** » Thu Dec 09, 2010 6:14 am

Before you take it to the shop you might want to indicate where you want the holes drilled to attach the base to mast step on the deck. I don't see any holes in the center of the base.

Also, I would make a trace of the base of your mast. Then the shop can fab a collar for the mast to fit into and pre-drill for the bolts/rivets to hold it in place.

Banshi · Post by **Banshi** » Thu Dec 09, 2010 6:27 am

Aside from the fastening issue the only thing I see wrong is the radius of the corner at the bottom of the top plate. It needs to be the same as the distance from the center of the pivot pin hole to the edge of the plate to prevent it from binding as the mast stands up. The pivot pin hole might also be slightly slotted vertical to allow some up and down play to be sure the vertical load of the mast sets directly on the base plate and not just on the pin. I like it.

John Stahl · Post by **John Stahl** » Thu Dec 09, 2010 8:06 am

I forgot to put the radius of the holes in the drawing. The top plate pivot holes are 3/8 the radius of the bottom plate pivot holes is 1/2. So I have some play in the hinge.
I will make the correction to the drawing

The holes to attach the base are an unknown to me and I can do that when id know them.
FYI I have built an autogyro and drilling holes for this project is a peace of cake.

Would you use aluminum or stainless steal?
I have the aluminum; it is leftover from my gyro build.

hp18carr · Post by **hp18carr** » Thu Dec 09, 2010 8:10 am

Precisely

All in fun, but sometimes as I read the posts on this forum I can't help but laugh ( at myself). I truly think if a survey was taken 9 out of 10 on this forum would have a degree in some form of Engineering... I would be number ten.

Terrence
Wilmington N.C.
Chrysler 26' 1980
Pandora (for now)

Banshi · Post by **Banshi** » Thu Dec 09, 2010 8:26 am

For me stainless, but with aluminum laying around it may be worth a try. I would worry about bending it and it cracking with the sharp angle of the corner.

John Stahl · Post by **John Stahl** » Thu Dec 09, 2010 9:11 am

Terrence
I am in the boat with you. I never even took a drafting course in high school. I am a self taught engineer

To prevent cracking of the aluminum all you do in increase the radius of the bend from .25" to .5".

sauerleigh · Post by **sauerleigh** » Thu Dec 09, 2010 10:13 am

No degree here, just years of making mistakes.
6061 T6 aluminum will have to be annealed to do any bending.
SS would be my choice.

Capt. Bondo · Post by **Capt. Bondo** » Thu Dec 09, 2010 10:23 am

All I can say is WOW

The discussion that took place above is what makes this forum so great.
People talking through ideas, and coming up with great designs to fix problems

Keep it up

Bhacurly · Post by **Bhacurly** » Thu Dec 09, 2010 11:18 am

FWIW

Here is what I got for my project boat...

http://www.blumhorst.com/catalina27/ima ... hinge3.jpg

And this is how they installed theirs:

http://www.blumhorst.com/catalina27/mas ... nstall.htm

Not that I find anything wrong with yours

I don't have the tools to make one like some of you folks!

Billy

Alanhod · Post by **Alanhod** » Fri Dec 10, 2010 10:24 pm

John,

That looks like a real good concept to me. I think my heart and mind would go with stainless steal, but my wallet would vote for Aluminum. I sail on the Ocean so I think the stainless steel would win the tie breaker.

Bill,

I like yours too, but what holds the mast from hinging backward? Is the Fore stay the only thing from keeping the mast from laying back down?

Now that I think about it I guess my fore stay, back stay and shrouds are really all that hold my mast in place with the center post keeping the base from shifting around. Hmmm, I learned something new that I had already seen but never really thought about.

I like that center post on the lower plate going through the upper plate to keep the base from shifting about. I like that a lot.

Thanks
Alan

John Stahl · Post by **John Stahl** » Fri Jan 21, 2011 2:45 pm

The Mast step repair is compleated!!!

http://s1082.photobucket.com/albums/j37 ... %20repair/

Kevin Dreher · Post by **Kevin Dreher** » Fri Jan 21, 2011 3:06 pm

looks good, one question....how will you keep the mast from moving side to side. i imagine that any movement side to side with a solid pin with no movement would cause a lot of stress on the fiberglass. maybe i am wrong or over thinking it.

John Stahl · Post by **John Stahl** » Fri Jan 21, 2011 3:14 pm

I dont understand your question. did you look at all the photos? I think you will see we have changed nothing. the hinge is only to keep the mast from twisting as it is rased. one thing we did change is the looks.