Com-Pac Yacht Owners Association

Com-Pac Model Specific Discussions => CP-19's => Topic started by: Andy Knoczek on December 15, 2016, 03:00:21 PM

Title: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 15, 2016, 03:00:21 PM
OK, I think I did a thorough look-see-search through the archives and can't seem to find a good explanation regarding the mast tabernacle and it's role of handling the stresses during a mast "Tilt" - Let me explain what I am looking for:

I have a CP19 I am wrapping up getting finally off the hard and out of the $200/month marina. I have the opportunity to save said $200 by keeping it at the dock at the house I am renting. The issue is: I only have a one-way into my canal system and it entails going under a 15' clearance bridge. So I would need to (1) Lower (tilt) to an angled height less than 15' (2) KEEP it at that angle while going under without sway (3) hike it back up and attach forestay.

There have been some fine gin pole examples here and I have the one in mind, so I plan to have a 2x4 system through bolted at the tabernacle and using blocks. I will make temp baby stays from the mast 8' off the deck in-line with the mast center.

The above rig I have a good handle on, but have one concern: The tabernacle. Now I have read here a couple thoughts on the thru-bolting of the tabernacle vs. the stock screws into the deck only, the latter breaking away harmlessly in the case of a dismasting. That makes sense. BUT... If I am going to be lowering, holding at angle, and raising, would the tabernacle be strong enough to keep the mast base in check during this process? I have read some had break-away due to deck compromise. My deck is very solid and I can only think that the screws would be in securely. Would this be enough to keep it in place? Or with the setup I have, should I just take my chances, or do a thru-hull 4 bolt system like some of you experienced folks have done? - My main concern is regarding the loosening of the mast-base-tabernacle bolt to let the bolt slide up and down that slot, but due to baby stay tension, it would keep the mast base tight to the tabernacle and instead of traveling up that pivot point, it would lever-effect and tear out the tabernacle... any thoughts? Thanks much!
Title: Re: Mast TILTING (not "raising") question
Post by: Tim Gardner on December 15, 2016, 04:00:30 PM
Don't use baby stays, that will tear out the tabernacle.  I used to use a sliding fulcrum.  I built it out of a SS boom gooseneck slide from dwyer, two eight foot aluminum conduit poles flattened a drilled at each end and two sliding cars mounted on my genoa tracks.   I also bolted an eye in the mast groove at the base of the mast about 3" up from the bottom.

I would lower the sail  below the gate, insert the slide, bolt one end on each pole through the eye and the other ends to the cars.  This makes a pretty good truss.  I also attached a block  to the tabernacle through which a line led from the slide eye through the mast base eye and then to my port winch. also I had a lever type disconnect on the forestay.  To lower the mast to the correct height, I made fast the fulcrum by taking slack at the winch, released the forestay,  then slowly allowed the slide to travel up the mast groove, causing the mast to lay aft to the desired point, then made fast the line.  To raise the  mast back to full up position, I just winched her back up, pulling the slide and the fulcrum back down the groove, and reattached the forestay. The tension on the slide line at the base of the mast kept the mast from levering the tabernacle out of the deck

One thing though, you must have a roller reefing gooseneck on your 19 and set the boom 90^ from normal or the boom won't swing far enough up towards the mast to attain a 15" mast height.

Dwyer will make you an extended gooseneck long enough to swing the boom right up against the mast if you want. 

I don't have any pictures of this rig, and because my boat camps out at my dock, I don't use it often.  I built it to go under a 14' bridge.  If I was trailer sailing a lot it would be my one armed mast raising rig.

TG
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 15, 2016, 04:33:17 PM
Thanks Tim, but I am having a problem visualizing... you are saying the fulcrum attached to the slide on the mast is the fulcrum point with the mast being unbolted from the tabernacle then tilted back at that slide being the pivot point?
Title: Re: Mast TILTING (not "raising") question
Post by: wes on December 15, 2016, 09:24:59 PM
You know what I would do? Find a slip on the other side of that bridge. Don't care what kind of rig you create, that 19 mast is heavy and unwieldy and it's a challenge for two adults to handle even on the hard. I would not want to do it on the water while underway, every time I went sailing.

On a 16, maybe.

Wes
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 15, 2016, 10:32:44 PM
I appreciate the sentiment Wes, however... my options are limited, and I would only be taking her out 1 or 2 times per month staying out a whole weekend when I do (Fri eve till Sun eve) - the waters near the bridge are calm and sheltered. Only a tidal swift flow pre-post slack-tide. I just need a system to hold it up on tilt while I go under, I don't have any problems even if I had to remove the boom and sail. I would be motoring another 10 miles to my closest inlet on the east coast (St Augustine). Thanks.
ps - I've seen MacGregors touting this ability/rig on their bigger 26' M and X models... why couldn't it be done on my little CP19?
Title: Re: Mast TILTING (not "raising") question
Post by: Potcake boy on December 16, 2016, 12:24:54 AM
Andy,

When I had my 19, it came with a gin pole and tackle to raise/lower the mast and didn't require any side stays. I never tried it on the water which can be a bit more challenging. I'll have to admit that TG's method is quite genius and as I visualize it, should work very well. The gear should also be easy to store aboard once you've raised the mast again.

Of course, your other option would be to get a Com Pac cat boat. I think the newer ones with the attached raising system can be operated from the cockpit.
Title: Re: Mast TILTING (not "raising") question
Post by: Bob23 on December 16, 2016, 05:04:46 AM
  Andy, for what it's worth: PeterG (longtime member here and former 23 owner) installed a pretty hefty hinged tabernacle on his 23 before he sold her. I plan to install the same thing on mine.
  Here in NJ, I have a good friend who sails a Bristol 34 and lives upriver to a low bridge which requires him to partially lower the mast every time he sails in the bay near his home. He has a similar hinged tabernacle and has devised a lowering system using a 12 volt winch from Harbor Freight. Although I have not seen it in action, friend Steve explained how it works and he's used it all summer. The winch is mounted on a wood board and is temporally mounted on the foredeck when needed and is operated from the cockpit which allows the operator to also guide the mast into the crutch. I can get some info from him if you'd like.
  Obviously, the mast is much higher and heavier than your Compac 19 mast and he's had no problems. I plan to build the same thing for my 23 as there are some low bridges on waters nearby that I plan to explore.
Cheers!!!! Bob23
 

Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 16, 2016, 09:23:36 AM
Thanks Bob, sure! Anything you can share would be great. It's funny you bring up the hinged tabernacle because that was going to be my next question of suggestion. I've seen the MacGregor videos showing their system and noticed they have the hinged tabernacle. This would eliminate my fear that sliding/pivoting bolt-thru would lever the tabernacle. Is there a mfg of one that would work with my mast? Thanks!
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 16, 2016, 11:18:35 AM
In a past post, http://cpyoa.geekworkshosting.com/forum/index.php?topic=8376.0 (http://cpyoa.geekworkshosting.com/forum/index.php?topic=8376.0) - philb had a nice simple design I was going to try to replicate. Either with the wood, or using metal pole bolted thru to strapping/plate to connect to the thru bolt on the tabernacle-to-mast.
This system makes sense, but would the load on the tabernacle be too great? I would make a mast crutch higher than the deck to lay into. I don't know the history of how often in the past the mast was lowered on my boat, but scoring around the mast bolt slot in the tabernacle shows wear as it was done more than once in the past.

(http://i1125.photobucket.com/albums/l594/CPYOA/cp19%20lowering%20mast_1.jpg)
http://http://i1125.photobucket.com/albums/l594/CPYOA/cp19%20lowering%20mast_1.jpg (http://http://i1125.photobucket.com/albums/l594/CPYOA/cp19%20lowering%20mast_1.jpg)
Title: Re: Mast TILTING (not "raising") question
Post by: Tim Gardner on December 16, 2016, 11:37:08 AM
Andy,  for mast fittings and hinges go to : https://www.dwyermast.com (https://www.dwyermast.com)

This is the gooseneck slide I used to make the A frame slide up the groove

(https://www.dwyermast.com/images/dh417ssm.jpg)

Hinged mast step:

(https://www.dwyermast.com/images/dh2112hsm.jpg)

Here is the car:

(http://newcontent.westmarine.com/content/images/catalog/full/545012.jpg) from west marine

A Frame:

(http://i987.photobucket.com/albums/ae355/tigar100dner/AFrame.jpg)
The advantage of the a frame is it stabilizes the mast side to side without using baby stays

TG
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 16, 2016, 11:47:32 AM
WOW ! Thanks Tim! I was just about to post the question: Would it look like this:

(https://i.imgsafe.org/41994f0a13.jpg)
Title: Re: Mast TILTING (not "raising") question
Post by: Tim Gardner on December 16, 2016, 11:59:01 AM
Yep - That's about it.   In your case, (since it looks like you do not have a stern rail) if you add a third, shorter leg and a cane rubber, it could also act as a mast crutch when you trailer the boat.  You just lower it all the way down to til the third leg meets the combing then un-pin the hinge, slide the mast forward and rest it on your bow rail.

TG
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 16, 2016, 12:06:22 PM
Yeah, she is on the hard while I am renovating. I do not plan to trailer at all since I have a dock where I rent. It will only be tilt, go under, raise, sail! Thanks so much for your time and input! I appreciate it much!
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 16, 2016, 01:26:35 PM
Hi Tim, thanks again! just a couple more details when you can...

1) what diameter pipe do you use?
2) was is the dimension and angle of the flattened ends?
3) if the gooseneck slide track eye is where both flattened ends go thru with a bolt, should the bold be over-tightened?
4) how tight should bolts at the track cars be?
5) how close to the forward end of the tracks would the cars usually go?
6) the gooseneck slide shows both a mast parallel and perpendicular eye, which gets tied and which gets the bolt?
7) in your experience, how hard was it to adapt the hinged mast?
8 ) is the gooseneck slide prone to binding on the way up or down?

I figured I could build the A frame and bolt/sliding hw, then take the mast down while on the hard, install the hinge tabernacle, put it all back together - AND be one step closer to the water. Just a rub-rail and some electrics and I can have her on my dockside to really get her together! Thanks again Tim, your system sounds exactly what I need!

Andy K-
Title: Re: Mast TILTING (not "raising") question
Post by: philb Junkie19 on December 18, 2016, 01:44:20 AM
Andy,
I agree that Tim's design is much better suited to working with your mast on the water than my gin pole and baby stays. My rig works fine on a trailer. In the water with any of the boat's normal side to side motion, not to mention a power boat's wake, the solid A frame support would limit the mast swaying side to side which you clearly do not want.

The new free standing mast my 19 is keel stepped and made from round aluminum tubing (mostly) and spruce for the top section. This year two of us stepped and unstepped it with a single "stationary" gin pole with rope stays and the boat on the trailer. The pole had to be higher than the center of the mast which mast is stepped through the hatchway and the tall gin pole gets bolted in the original mast step. The stays were cleated aft. going through through blocks on the old jib tracks.  For the stays I used static kermantle rope that I had on hand and which has very low stretch especially under a relatively light load. Getting the pole set was a bit of a challenge and I found that even minimal stretch can allow some unwanted motion. My friend and helper still talks to me and is willing to help again in the spring so I guess it wasn't too bad.

I hadn't been thinking about it but the rig change leaves my original gin pole, pictured above, along with the lower baby stays sitting in the barn. I'm using the block and falls elsewhere and scavenged the eyebolts from the gin pole and maybe a couple of the snaplinks from the stays. I started out to say if any 19 owner wants them but they sound less attractive as I write. Maybe not worth the shipping cost which probably wont be cheap due to its non standard length and the weight.  I just spent $47 Saturday to Fedex a medium sized box to my grandson two states away to guarantee it would gt there before the 25th. Still, if someone does want them let me know. 
Title: Re: Mast TILTING (not "raising") question
Post by: Bob23 on December 18, 2016, 03:23:40 AM
Tim: Is that hinged mast the same one PeterG used on his 23 which is by Ballenger Spars? I see one on their website with a part number HMB SC27. Do tell all!!!
Bob23
Title: Re: Mast TILTING (not "raising") question
Post by: Tim Gardner on December 18, 2016, 06:33:08 AM
Andy,
I used 3/4" aluminum conduit with the ends flattened for at the mast slide end 1.25" and bent 45^. The other end I slotted.375" wide x 1" deep.  The mast ends were connected to the gooseneck eye bolt.
The track ends were slid down over the car eye and fastened wit a 1/4 " bolt and wing nut.

The Condit was 7' long. And I placed the cars about 6" from the forward end.  Your mileage may vary because you intend to only go partway down.  The slide did not bind, but dry lube was necessary.

This rig is now on my H23.
TG
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 18, 2016, 10:18:47 AM
Thank you Tim for the spec explanation! This will be my next endeavor to conquer after I get the new rub-rail on (I ordered from Matt at CP). I guess I will also incorporate your suggestion to have a goose-neck pivot to keep the mainsail and boom installed. I originally just figured I would get the boom and rigging back on after handling the mast - find a place to anchor and handle the boom, sail and sheets.

And thank you for the offer Phil, I appreciate it. My main issue is being a total independent with really no help, making a system I could use to keep as stationary as possible and still motor to my dock is paramount. I think I will enlist a hand for the maiden voyage just to have help getting it to the dock, where I can have a quiet place to construct and institute an a-frame system like TG has posted (not to mention take the time to save up money for the hardware! ><$$$$><).
I appreciate your response as your system was my main inspiration to at least have a way to get the mast down. Phil, I do have a question for you when using your original system as pictured above:

Did you have any failures of the mast tabernacle? What happened when you lowered your rig at the bolt-slot point? Does the bolt ride-up the slot even having baby stays taught? Thanks much again!

Andy K-
Title: Re: Mast TILTING (not "raising") question
Post by: philb Junkie19 on December 18, 2016, 12:20:31 PM
Andy,
There were no problems with the mast tabernacle. The mast pivoted on the long bolt that went through the mast and pole base and was not snugged.  The bolt did slide up in the slot as the mast pivoted on its heel. The Sta-set had enough slack and stretch for that. The forces on the tabernacle and screws are different from Tim's A frame. His fulcrum starts low on the mast with the heavier part of the mast above which creates those upward forces on the step. My fulcrum was above mid point on the mast creating downward and forward forces. If my attachment point was low in the mast I would risk losing it sideways or having the step yanked.  The tabernacle does not appear to be overly stressed used this way.  Its been a while since physics class but that's how I understand it,

My rig worked well single handed on the trailer. The mast would move a little from side to side on its up or way down but that was fine. You also have to lower it by hand the last way into the crutch. This was just fine on land. The thought of using it single handed or otherwise on the water approaching a bridge is scary. Tim's design is so much more secure and worth the investment.
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on December 18, 2016, 12:59:07 PM
Thanks Phil... that's what I was wanting to know exactly!
OH, TG ! and another thought... seeing those track cars are over $100 for both... maybe I could just adapt an eye at the stanchion bases with some form of bolt-on eye for the pipe bottoms to bolt to? It would bring that connection point 6-8 inches forward from the track position you mentioned...

AND... to all interested in giving input, the bridge I am going under is in an extremely calm area. Surrounded by structure, virtually no wind influences. Also in a NO WAKE year round zone with almost no boat traffic. So pitching/heaving would not be an issue during the lower, tilt, hold, raise, secure to forward process :-)
Title: Re: Mast TILTING (not "raising") question
Post by: cal27sailor on January 14, 2017, 10:28:23 PM
I really like Tim's system.  I have seen similar systems and want to try to build one for my 19.  I have tried the wooden gin pole and baby stays system repeatedly and have never been able to get it to work....and I have ripped my tabernacle out of the deck using it.  My plan is to actual use both the 12 volt winch with a remote control and the fulcrum system.  I think that will give me more control over the mast and the ability to easily pause in he lifting if I need to make adjustments one free a snagged stay. 

Tim- thanks for posting the photos of the hardware and the diagrams.  Now I have something to do this winter!

Tony
Title: Re: Mast TILTING (not "raising") question
Post by: Andy Knoczek on January 17, 2017, 11:15:40 AM
Thanks to Tim's great info, I have started constructing the system. Tony's confirmation of tabernacle damage makes me feel better about not trying the gin pole and baby stays. I have reinforced the midships stanchions and added an eye-bolt to attach the frames to (Saving $100 for the u-bolt-track cars). I am hoping the eye-bolt position will be far enough aft to keep the elevated support. As I hope to do the crutch support as well like Tim suggests.
However I am still trying to locate aluminum poles. Lowes has 8' x 1" square stock that I will probably try. I'm just having trouble figuring out how to properly squeeze and bend the pole ends without breaking or compromising strength. I guess I can try good old-fashioned hammer-time. But forming the angles will be tricky. Here are some pics of what I have done so far:

(https://i.imgsafe.org/e400b01d7e.jpg)
(https://i.imgsafe.org/e4001686c8.jpg)

On another note - The stanchions when I got the boat had tiny fender washers - no backing. I was concerned for extra strength here, so decided to beef up significantly. Hoping not too much overkill.

Also, I figured out the mast I have isn't factory original, at least I don't think so. This is the dimensional and part from Dwyer which is my exact. So I will have to get the tabernacle hinged set and organizer, after I save some more $$ of course :-)

(https://i.imgsafe.org/e415401fb0.jpg)
Title: Re: Mast TILTING (not "raising") question
Post by: Craig Weis on January 29, 2017, 09:25:24 AM
Mast tilt?

when I talked with Mr. Hutchins at the All Sail Boat Show at Navy Pier years ago I asked him that question.

He said straight up and down.

Craig Weis