Good Evening All,
IN my search for a ComPac Horizon Cat, I noticed two versions of the MastTendr system
Older ones:
These have a removable bin pole. Once raised, you pin the mast, remove the gin pole and attach the forestay.
Newer ones:
Have a flip up gin pole thingy attached to the mast (like the Sunday Cat) and a block/tackle on the forestay. With this version, you flip the gin pole thingy up, raise the mast, put in the safety pin and you are good to go. The block and tackle stay in place.
A few questions:
Is the newer one an improvement?
Did the newer version help with the difficulty of raising the mast the first few feet?
I would really appreciate your thoughts on the two versions.
Thanks in advance for your thoughts/opinions.
Dan
I don't have first-hand knowledge of the HC mast raising systems, but this question has come up recently and in researching the issue I ran across this description of the older system you reference.
https://www.youtube.com/watch?v=k59DsMHQRVw
With no additional mechanical advantage on the Mastendr Plus system (the Sunday Cat version you refer to), other than the winch seen in the attached video, and a shorter gin pole, I don't see how that will improve the initial lift. As you suggest, the difficulty is getting the thing started, once raised a few degrees it becomes easier. I suspect most just walk it up until hauling on the line becomes more effective.
Maybe they changed the winch purchase with the Mastendr Plus on the HC.
Thanks Bruce
One would hope the 2nd version is an improvement. Although looking at it, i am not sure.
I will check out the video
The video is interesting. It appears to use version one of the system.
My boat is a 2021 and has the version you have tagged as one or the older. Are you sure you are looking at the Horizon? The description looks like the Legacy Sport. There has to be someone on this board that has a newer model, Horizon. BTW, when I step the mast, I push the mast up to about a 45 deg angle standing against the companionway as I pull the lifting line tight in the clutch. Then I use the winch to finish of the job. Works for me. I am not strong enough to use the winch from a full down position. Sail On, Al
Could not sort out how to add a video here
Put one up on the Compac owners Facebook group
Link To Facebook post with video (https://www.facebook.com/share/p/17T7P1ZUPt/)
Quote from: alsantini on December 09, 2025, 11:50:58 AMMy boat is a 2021 and has the version you have tagged as one or the older. Are you sure you are looking at the Horizon? The description looks like the Legacy Sport. There has to be someone on this board that has a newer model, Horizon. BTW, when I step the mast, I push the mast up to about a 45 deg angle standing against the companionway as I pull the lifting line tight in the clutch. Then I use the winch to finish of the job. Works for me. I am not strong enough to use the winch from a full down position. Sail On, Al
Good Question. Yes, I am sure I am looking at an Horizon Day Cat.
Not that it really matters, but are we sure that Com-Pac ever marketed the HC with the Mastendr Plus to replace the existing design? Al's 2021 is pretty new, I'd bet not that many additional HCs were built, maybe 5-10, and he has the original system. I mostly associate the Mastendr Plus with the Sunday Cat, the only gin pole version they offered on that boat to my knowledge. I know of a 2016 Sunday Cat so equipped, and it may well have been available earlier.
The Mastendr Plus was offered as a stand-alone package for retrofitting any Mastendr mast, to offer a gin pole on models that didn't have the option. I know of one 2010 SC that was fitted with one in 2024, to make it easier to do from the cockpit while tending young kids. I've even heard on one being installed on a PC; wouldn't occur to me! I see reference to a Boomtendr Plus on a Legacy Sport, not sure how they might differ.
I agree Bruce. I don't think there are two systems for the Horizon. the "improved" system showed up on the SC and the Legacy, I think. BUT, I have been frequently wrong. LOL Sail On, Al
Quote from: alsantini on December 09, 2025, 03:26:48 PMI agree Bruce. I don't think there are two systems for the Horizon. the "improved" system showed up on the SC and the Legacy, I think. BUT, I have been frequently wrong. LOL Sail On, Al
Any thoughts on the video showing a Sunday cat type system on our Horizon Day Cat? Do you all think someone did this after the sale?
Boat is kind of unique. It has a 6 speaker stereo system that Com Pac factory installed. 4 speakers in the cockpit and 2 in the cabin. Would not surprise me if they also had the Mast tender system up graded to the mast tender plus.
What does not make sense to me is, if the MasTendr + worked better than the stock MastTendr, why did Compac not make it a standard item on HC and HC Day?
Over 45 years, we have owned several compac boats. Compac was always upgrading the models with their latest. I wonder if it was a limited improvement that did not warrant putting it on all HCs.
I think that's the point. The Mastendr Plus may not be better than the original HC system on the HC, and indeed may not have been intended to be. The Day Cat sailor may have liked it better because it is more self-contained, not messing around with a separate rod. Since he had an open cockpit it was easy enough to walk the mast up for the first bit. With a shorter gin pole, and no other increase in leverage, I don't see how it would be better at lifting the mast.
I don't do Facebook so I couldn't see what you posted there. I can post what you have here on the CPYOA, send me a PM with your email and I'll get back to you.
Quote from: bruce on December 09, 2025, 07:28:06 PMI think that's the point. The Mastendr Plus may not be better than the original HC system on the HC, and indeed may not have been intended to be. The Day Cat sailor may have liked it better because it is more self-contained, not messing around with a separate rod. Since he had an open cockpit it was easy enough to walk the mast up for the first bit. With a shorter gin pole, and no other increase in leverage, I don't see how it would be better at lifting the mast.
I don't do Facebook so I couldn't see what you posted there. I can post what you have here on the CPYOA, send me a PM with your email and I'll get back to you.
Concur. All good points
Although, the block and tackle on the MastTendr + should give lifting force advantage.
A search of picts on the internet has shown some have it and some don't. Does not seem to be any correlation to year. Plus a gent on the Facebook group said it was an option when he ordered his 2024 HC.
I shouldn't be hard to retrofit either system onto whatever HC you got. I'm glad you found a Day Cat to consider, they're pretty scarce.
Good luck in your search!
Quote from: bruce on December 10, 2025, 08:32:03 AMI shouldn't be hard to retrofit either system onto whatever HC you got. I'm glad you found a Day Cat to consider, they're pretty scarce.
Good luck in your search!
Concur. I suspect they built far fewer of them than the original HC.
Some comments about the MastendrPlus system from the sailor of a SunDayCat:
My SunDayCat is a 2012 model and has the MastendrPlus system. It is my understanding, subject to correction if mistaken, that the SunDayCat has always been equipped with the MastendrPlus system, and that the MastendrPlus system was available on the SunCat only as an option.
The height of the integrated gin-pole is determined by the horizontal distance from the mast hinge to the bow of the boat. This is because it is necessary for the block-and-tackle to be aligned perpendicularly to the gin-pole when the mast is upright. This brings the end of the gin-pole directly above the block-and-tackle's anchor point on the bow of the boat.
My block-and-tackle has a 4:1 purchase. That does not give enough mechanical advantage force multiplication to lift the mast off of its cradle. Certainly, a longer gin-pole could provide more leverage, but only if the block-and-tackle's anchor point could also be brought further forward.
I raise the mast this way. Standing about in the center of the cockpit, I manually raise the mast off of its cradle and rest it on my shoulder. From there I manually raise it with the line of the block-and-tackle (there is no winch). I do not pull on the line hand-over-hand. Rather, I hold the line and lean back to use my body weight to pull the line. (Note that the line is pulled through a locking friction clutch so it will hold position if the grip onto the line is released.) As the mast rises, it tends to wander off center, especially if the trailer is not perfectly level side to side. I use one hand to guide the mast to center by pulling or pushing on a side stay, as necessary. When the mast is about 80% raised the side stays are losing their slack and hold the mast near-center. Then, because the mast is now nearly upright, I pull hand-over-hand until the side stays go taut and the mast becomes centered. Then I pull as hard as I can, with both hands and my body weight, to apply tension to the forestay. Note that the tension in the forestay is limited by the amount of force I can apply to the line through the block-and-tackle. You can feel when the hinge is fully closed into its upright position because the pulling force opposition rises dramatically. (The locking lever of the SunCat's Mastendr system may apply greater forestay tension than what pulling on the SunDayCat's block-and-tackle's line can apply to the forestay. So, the MastendrPlus system may provide greater convenience at the loss of forestay tension.)
In my opinion, others may disagree, it is necessary to apply sufficient tension to the forestay so that the hinge stays fully closed under sailing conditions. This ensures that the bending, compression, and shear loads within the mast are carried through the hinge by vertical contact and the hinge collars and not by the hinge ears and pivot pins. An implication of this is that you ought not over-tension the side stays making them act to pull the hinge back somewhat open. I have adjusted my side stays so that I can just get the hinge fully closed in my final pull on the block-and-tackle's line.
Although this discussion is about raising the mast, the MastendrPlus system is also helpful lowering the mast under control.
Bruce, if I recall correctly, the Boomtendr system is a scheme where for trailering the boom is folded up along the mast and then the boom and mast together are lowered to the mast cradle. Not sure how the sail is flaked between the boom and mast or how the folded-up boom is fastened to the mast. Perhaps an owner can enlighten us.
Regards, Roland
Quote from: Roland of Macatawa on December 10, 2025, 03:58:07 PMSome comments about the MastendrPlus system from the sailor of a SunDayCat:
My SunDayCat is a 2012 model and has the MastendrPlus system. It is my understanding, subject to correction if mistaken, that the SunDayCat has always been equipped with the MastendrPlus system, and that the MastendrPlus system was available on the SunCat only as an option.
The height of the integrated gin-pole is determined by the horizontal distance from the mast hinge to the bow of the boat. This is because it is necessary for the block-and-tackle to be aligned perpendicularly to the gin-pole when the mast is upright. This brings the end of the gin-pole directly above the block-and-tackle's anchor point on the bow of the boat.
My block-and-tackle has a 4:1 purchase. That does not give enough mechanical advantage force multiplication to lift the mast off of its cradle. Certainly, a longer gin-pole could provide more leverage, but only if the block-and-tackle's anchor point could also be brought further forward.
I raise the mast this way. Standing about in the center of the cockpit, I manually raise the mast off of its cradle and rest it on my shoulder. From there I manually raise it with the line of the block-and-tackle (there is no winch). I do not pull on the line hand-over-hand. Rather, I hold the line and lean back to use my body weight to pull the line. (Note that the line is pulled through a locking friction clutch so it will hold position if the grip onto the line is released.) As the mast rises, it tends to wander off center, especially if the trailer is not perfectly level side to side. I use one hand to guide the mast to center by pulling or pushing on a side stay, as necessary. When the mast is about 80% raised the side stays are losing their slack and hold the mast near-center. Then, because the mast is now nearly upright, I pull hand-over-hand until the side stays go taut and the mast becomes centered. Then I pull as hard as I can, with both hands and my body weight, to apply tension to the forestay. Note that the tension in the forestay is limited by the amount of force I can apply to the line through the block-and-tackle. You can feel when the hinge is fully closed into its upright position because the pulling force opposition rises dramatically. (The locking lever of the SunCat's Mastendr system may apply greater forestay tension than what pulling on the SunDayCat's block-and-tackle's line can apply to the forestay. So, the MastendrPlus system may provide greater convenience at the loss of forestay tension.)
In my opinion, others may disagree, it is necessary to apply sufficient tension to the forestay so that the hinge stays fully closed under sailing conditions. This ensures that the bending, compression, and shear loads within the mast are carried through the hinge by vertical contact and the hinge collars and not by the hinge ears and pivot pins. An implication of this is that you ought not over-tension the side stays making them act to pull the hinge back somewhat open. I have adjusted my side stays so that I can just get the hinge fully closed in my final pull on the block-and-tackle's line.
Although this discussion is about raising the mast, the MastendrPlus system is also helpful lowering the mast under control.
Bruce, if I recall correctly, the Boomtendr system is a scheme where for trailering the boom is folded up along the mast and then the boom and mast together are lowered to the mast cradle. Not sure how the sail is flaked between the boom and mast or how the folded-up boom is fastened to the mast. Perhaps an owner can enlighten us.
Regards, Roland
Wow!
Richard, thank you for the very well written description.
I can now visualize the operation of the system.
Big thanks,
Dan
Always good to hear from you, Roland. Your engineering background shows ;).
I've been following the Com-Pac catboat line since 2010 when I was looking for a boat. I would have guessed the Mastendr Plus was later than 2012, but clearly I would be wrong.
I haven't heard of the hinge opening under sail, although you may have mentioned it and I didn't pick up on it. The hinge, compared to the Marshall Marine hinge for example, is relatively under-engineered, but I've heard of few if any failures. The curved pin, if used, would provide some reinforcement. Neither the SC or the PC carry a lot of sail for their size compared to other catboats. I haven't noticed any opening of the hinge on my PC under any conditions, using the stock wire cable forestay and Highfield lever. I'd consider stretch in the Mastendr Plus line as a possible source of the hinge opening. Not sure what line they used, but there may be newer lower-stretch lines that could be beneficial. Certainly if the shrouds are over-tensioned and the hinge doesn't close is a problem.