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Catalina/Capri 25/250 Sailor's Forums

Catalina 250 Specific Forum

A frame question

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SCnewbie
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166 Posts

Initially Posted - 03/12/2008 : 07:07:33

So I am building an A frame to take the mast down on our new boat. Thanks to Arlynn for his very helpful site. I wondered though, how tall should I make it?

S/V Cornbread
1995 C250WB #161
Charleston SC

Edited by - on

JohnP
Master Marine Consultant

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Response Posted - 03/12/2008 : 12:35:25

On my C25 the mast is 28' tall, and 12' poles gave me plenty of leverage for single-handed lowering of the mast.

Others have used 10' poles. Still others drop the mast by hand with a crew of 2.

Before I went ahead I made diagrams to help myself understand what would happen with my mast & A-frame as I lowered them: [url="http://www.catalina-capri-25s.org/forum/topic.asp?TOPIC_ID=16867"]previous anchor light thread[/url]

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SCnewbie
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Response Posted - 03/12/2008 : 16:29:36

I have a couple of guys to help me on Friday actually which is when we plan to drop the mast. Would I be just as well off with the three of us wrestling it than trying to build a frame? My san juan mast I can lift by myself but obviously the mast on the 250 is a bit larger.

Edited by - SCnewbie on 03/12/2008 16:37:40

Mike013
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Response Posted - 03/12/2008 : 17:18:33

I had to drop the mast while Ariel was in the slip. I had 4 guys helping, 2 on each line on each side. We rigged the baby stays to insure the mast stayed as close as possible to the vertical plane while it was lowered. This can be a problem if the water is active and the boat is moving around in the slip. Make sure the boat is firmly tied down to minimize movement. Next we rigged the standard mast raising gear which is a strap that goes around the mast, under the spreaders. That strap is tied to the main lines held by your helpers. Make sure you set up the crutch used to support the mast after it is lowered. Then follow the standard mast lowering instructions. The 4 helpers will insure that the mast does not fall to fast or hard. Lower it down to the crutch (mast support). Take care to insure that you do not mangle your shrouds turn buckles when you put the mast up again. Do it real slow and keep your shrould lines straight. Good luck.

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SCnewbie
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Response Posted - 03/12/2008 : 17:46:26

Thanks Mike. We will be doing it on the trailer. I have four guys available if needed and most are fairly strong fellas. I don't have the standard raising gear so I am making whatever I intend to use Thursday. Part of why it has to come down is because my shroud turnbuckles are mangled already. I need to move it to paint the bottom anyway but the shrouds are a job i am doing while it is down.

Edited by - SCnewbie on 03/12/2008 22:33:27

bear
Admiral

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Response Posted - 03/12/2008 : 18:14:54

For your consideration, when I have lowered the mast on Brandy manually I used the forward halyard with a rope extension attached and stretched out in front of the trailer quite aways. USED baby stays, this is a must. Two souls at the end of the outstretched halyard and two on the cabin roof. Be sure to tie up the turn buckles or they will bend. Be aware that as the mast approaches horizantal the souls on the cabin roof/cockpit will need to take control of the mast. I always laid something accross the sliding
window outside frame to let the mast lay on while souls repositioned to unhook mast and move it forward to the forward pulpit. If you have the Catalina rear mast holder that fits in the grudgeons this helps with it extended out all the way. JMTCW...

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Jarrett Anderson
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Response Posted - 03/14/2008 : 00:30:42

I know there are a lot of ways to get a mast up and many have been successful with their systems. I lost a mast while lowering the it on my last boat a Mac 25 using the jib halyard connected to a guide line. It just got away from us. No cross wind, sitting on the trailer. The force of the light weight mast on that boat ripped the 3/8" step bolts through the deck and bent the mast. I was lucky to get out of the way.

The A frame in the thread provided above is brilliant in concept. The 2x4's are grossly under par for the load that is exerted on them. The mast only weighs 300 lbs, but at points during the lowering the A frame could have more that 600lbs applied to it(force of rope countering mast). The bolt holding the 2x4's together may be able to handle the shear force being applied depending on the grade. The lightweight carabiners were lucky to with stand the mechanical advantage being applied by the 4:1 leading the the deck winch. How are the feet of the 2x4's secured to the deck and can the deck under the 2x4's handle the load the feet of the 2x4's are exerting on it (the mast step has a compression post under it). All stated the A frame is a great tool with the right components.

My vote is always to use a mast raising system with the mini stays it is worth the investment. If you are in CA, come borrow my trailer, it is just sitting in the driveway.

Whether you use mechanical advantage or bruit force, take it slow, have a spotter. The stays can get hung up on things and you can do a lot of damage.

Good Luck!
Jarrett _/)

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JohnP
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Response Posted - 03/14/2008 : 08:12:16

A bit of over-estimate on the weight and the forces involved - the mast weighs about 70 lbs on a SR and 75 lbs on a TR Catalina. Weight of a C250 mast? Dunno. Check out all the past discussions on mast-up & mast-down methods.

[url="http://www.catalina-capri-25s.org/forum/topic.asp?ARCHIVE=true&TOPIC_ID=5535&SearchTerms=mast+weighs"]mast weight[/url]
2x4's and moderate size hardware are fine for these moderate loads.

No info on a Mac 25. Sorry that mast got away from you.

Edited by - JohnP on 03/14/2008 08:15:53

Jarrett Anderson
1st Mate

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Response Posted - 03/14/2008 : 11:13:46

JIBE HO! I have never weighed the mast on a 250; I was using figures used in other threads (mast up mast down). If the mast was only 75lbs and it took 75lbs of force to move the mast you would be with in the load limits of the 2x4's. You still have not addressed the other concerns. My point was not to attack the design you offered, but throw in my 2 cents. After having a mast hit the deck I am a little passionate about the safety of the operation. The sailors on the site come up with brilliant ideas and know the ins and outs of their boats. Now if you were to build that A frame out of stainless steel, you might have something! ;-) I still believe the trailer mounted mast raising system with the mini stays is the safest operation.

Jarrett_/)

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bear
Admiral

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909 Posts

Response Posted - 03/14/2008 : 11:46:56

Jarrett, I have lifted the mast on my C 250 to reposition in the mast crutches. I would guess 70-75 pounds. Also I have changed out turnbuckles one at a time with the mast up if that is a concern. Just count the threads when unscrewing or turns of the turnbuckle. I believe the trailer mounted system is the best also, but many older trailers do not have that capability. The second best is Arlyn's system. We never came close to losing control of the mast using the jib halyard. I always tugged on the halyard with a lot more force than lowering it could generate. Whatever method you choose don't forget the Minni-stays.

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SEAN
Admiral

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Response Posted - 03/14/2008 : 12:22:05

I am thinking a 8` 1x3 with a v at the end , to catch the mast sooner .
standing in the cockpit . might be handy , somebody always wants to have a conversation 1/2 way down .

Edited by - SEAN on 03/14/2008 12:23:34

Nautiduck
Master Marine Consultant

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3704 Posts

Response Posted - 03/14/2008 : 13:04:13

I have just built a gin-pole setup for raising and lowering the mast when the boat is not on the trailer. In a few weeks, when we launch, I will post photos. Of course I will also use the baby stays. I would suggest you ask Catalina (they are very helpful) if you can retro-fit baby stays to your boat.

My advice is to over-engineer whatever you build. I am using 1 1/2" aluminum tubing with 1/4" walls for my gin-pole. You do not want to take any chance of the mast getting away from you. That 75 lbs will feel like a ton if it free-falls.

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John Russell
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Response Posted - 03/14/2008 : 14:47:59

I look at using the a-frame or gin poles or trailer mounted lifting system and mini-stays and boom crutch and all the other stuff kinda like wearing seat belts or using a belt and suspenders. You might get away with just muscling up the mast without any ill effects bt but, why risk it? The safety of these simple pieces of equipment far outweigh their cost in both dollars and <b>SENSE</b>. If something bad happens while raising or lowering the mast the potential is for it to be very, very bad.

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SCnewbie
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Response Posted - 03/14/2008 : 18:04:17

Well we got it down safely. Thanks for all the ideas and help. I ended up building something like Arlyn suggested on his site. I did an A frame secured at the base to the stanchions with 3/8" stay set. Both legs had 2 holes drilled in them that the stay set ran through. At the top I used JohnP's idea and used a good solid bolt as both the pivot and attachment point for the other hardware. I used heavy duty shackles in place of the D rings. I attached my Boom Vang on one end to the shackle and the other end I connected to a piece of 3/8" line attached to the eye ring in the anchor locker. I used a swivel block connected to another shackle at the top. I put a trailer winch on one of the legs of the A frame. I used Arlyn’s idea of wrapping a strap around the mast and hoisting that to below the spreaders with the halyard. I used a 1" heavy web strap but I didn't hoist it all the way up. I raised it until it was tight even with the block at the apex of the A frame. More 3/8" stay set was connected to the strap and through the block down to the winch.

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