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Re: mast raising system
Posted: Fri Aug 07, 2015 5:22 pm
by dlandersson
Yes, and I may not understand something (often the case)
Is the "new, improved" MRS for sale "out of the box ready" anywhere?
Tomfoolery wrote:81venture wrote:Yes, Just add the actual winch to the gin pole is really all you need to do
This is the brake winch used on the OEM

style MRS.
http://www.amazon.com/Dutton-Lainson-Co ... B00LKWYWY2
It will hold a load, and allow controlled lowering without risk of running away from you like a trailer ratchet winch will. But it costs more, of course.
Re: mast raising system
Posted: Fri Aug 07, 2015 6:02 pm
by Tomfoolery
dlandersson wrote:Yes, and I may not understand something (often the case)
Is the "new, improved" MRS for sale "out of the box ready" anywhere?
Tomfoolery wrote:81venture wrote:Yes, Just add the actual winch to the gin pole is really all you need to do
This is the brake winch used on the OEM

style MRS.
http://www.amazon.com/Dutton-Lainson-Co ... B00LKWYWY2
It will hold a load, and allow controlled lowering without risk of running away from you like a trailer ratchet winch will. But it costs more, of course.
Yeppers. Complete, right out of the box. Or so it says on the web site.
http://bwyachts.com/web%20catalog%20312 ... ng_kit.htm
Re: mast raising system
Posted: Tue Aug 11, 2015 5:50 am
by 81venture
Jesus...$200+ dollars??
I happened to score one for free, but after seeing it I realized if I just bought a brake winch and attached it to the Gin pole It is essentially the same thing as the $205 system sold.... I already had the baby stays from the first system.
Just relocated where I am winching from, instead of cockpit winch I stand forward of the mast and haul it up with zero effort.
I have since used a spare stay and some quick connects to install the tie off to the bow. Makes it easier to store
Dave
Re: mast raising system
Posted: Tue Aug 11, 2015 6:49 am
by Tomfoolery
81venture wrote:Jesus...$200+ dollars??
I happened to score one for free, but after seeing it I realized if I just bought a brake winch and attached it to the Gin pole It is essentially the same thing as the $205 system sold.... I already had the baby stays from the first system.
If you already have an old-style MRS, or even a home made one, the DL 350 lb brake winch is all you need, along with a block that's good for 500 lb or more (rope turns at least a 90 degree angle, so the block has to take at least sqrt2 times line pull). You don't need the pole, the tangs at the bottom, and the eye straps, as you already have them.
I've been toying with the idea of changing to the new style. Not because of the effort in pulling the line (5-parts on large ball bearing blocks), but because of the setup time. If I lower the mast to take the boat on a road trip, I leave the MRS rigged and pinned in place, so not much time there. But initial setup takes a little bit of time, especially if I get those 5 parts of line tangled.

I also have to pull the main halyard out of it's rope clutch, and feed the MRS line through it, as I use it to hold the mast when I have to stop. I'll probably never change over, but I think about it every time I'm sweating in the sun, re-running the lines because I passed one over/under something it should have gone under/over.

Re: mast raising system
Posted: Wed Aug 19, 2015 8:02 am
by 81venture
Since I removed the Furler and replaced the MRS with the newer style I can now launch and retrieve in about 10 min or so....seriously
I wouldn't go back to the rear cockpit winch MRS ever, could barely turn the crank until it got up enough to start pulling fwd more
Real PITA it was
Re: mast raising system
Posted: Wed Aug 19, 2015 8:23 am
by Tomfoolery
81venture wrote:I wouldn't go back to the rear cockpit winch MRS ever, could barely turn the crank until it got up enough to start pulling fwd more
Real PITA it was
There's more work involved in setting it up, I would think, but with 5 parts of line and ball bearing blocks with large sheaves, I can pull it up from it's mast roller with one hand. No winch needed, unlike with the original fiddle blocks.
But I would imagine the later version is easier to use. All that line with my system can get a bit messy, even though I take care to not let the blocks get inverted and/or tangled.

Re: mast raising system
Posted: Wed Aug 19, 2015 8:43 am
by Interim
@tomfollery Do you have a 5:1 system? Looks like a lot of power.
I've been trying to thing of a way to lift the mast without the MRS (will have one helper). Does anyone know how much force is needed to get the mast moving? If helper is in the cockpit and gets the mast head-high, can I pull a jib halyard (standing on the foredeck) to lift it the rest of the way?
My other plan is to have a come-along attached to the bed of my pickup, which would avoid having to attach/detach the MRS.
--john
Re: mast raising system
Posted: Wed Aug 19, 2015 9:03 am
by Tomfoolery
Interim wrote:@tomfollery Do you have a 5:1 system? Looks like a lot of power.
Yes, it's 5:1. Count the parts of line between the two blocks, or between the two attachment points that change distance as the line is wound in or payed out, in a more general sense. Lifting or pulling with one part involves no blocks, and two parts only requires one block, hence the more generalized statement.

It's hard to see all of them in the bottom pic, but they're quite clear in the top pic.
Interim wrote:I've been trying to thing of a way to lift the mast without the MRS (will have one helper). Does anyone know how much force is needed to get the mast moving?
I calculated almost 350 lb of force between the blocks, not counting friction in the line and sheaves, which is actually more complicated than it would appear. But the net force from the top of the MRS gin pole to the deck fitting, with a genoa on a furler attached as shown in the pic, is nearly 350 lb. It reduces as the mast goes up, both because the mast center of mass (or CG) is closer to the mast base in the horizontal direction (and directly over it or even forward of it when it's fully upright), and because the geometry of the MRS rigging improves as it goes up. That's all based on assumptions I made on the weight and distribution of said weight along the mast, including the furler and genoa.
Interim wrote:If helper is in the cockpit and gets the mast head-high, can I pull a jib halyard (standing on the foredeck) to lift it the rest of the way?
I don't know. Maybe if you're really strong. The problem is that as the mast is lowered, like if you can't hold it, or have to put it back down for some reason, or it just wasn't raised high enough to start with, the angle between the jib halyard and the mast gets smaller, and the smaller it gets, the higher the force required gets. As the angle approaches zero, the force goes to infinity. If it's tied to something, like the bow rail, you could end up bending something.
I'm not suggesting not doing that; just if you do, be careful so you don't damage something, or drop the mast on someone if the line or block breaks.
Interim wrote:My other plan is to have a come-along attached to the bed of my pickup, which would avoid having to attach/detach the MRS.
See the above admonition. It may work, if there's enough travel, but without the gin pole, as that angle collapses, the forces skyrocket. But if one is hoisting the mast manually, and the other is tailing it with the jib halyard, I don't see why this couldn't be done safely. Once the mast is half way up, the force to hold it gets small quickly, which I can feel in the MRS line. Tying the halyard off to the bow rail is, I believe, what most folks who don't use a MRS do.
Re: mast raising system
Posted: Wed Aug 19, 2015 12:25 pm
by Interim
Right. If I did a come along attached to the truck (appealing because it could be set up ahead of time), my attachment point in the truck is lower than the deck and would be working against me. Toss that idea.
I remember being really strong once (in fact, as time passes, the stronger I used to be), but that is not reliable now. We might try the "pull on the halyard" method, and if that doesn't work then it's back to the gin pole and MRS. If we do that, the idea posted above about having it rigged ahead of time will help speed things along.
--jf
Re: mast raising system
Posted: Wed Aug 19, 2015 2:15 pm
by Jimmyt
Tomfoolery, I don't know that your MRS is any more tangle prone than the new one (or maybe it's just the fact that I'm an idiot and could tangle up a rock). I learned to leave mine connected at the mast base, and just coil the lines neatly and bungee them to the MRS pole when I go out for the day. When I took it off and stored it below, it turned into a pretty good mess (in a hurry and just tossed it under a seat), and just took more time to reconnect it at the end of the day. That looks like a pretty sweet setup you have worked out, and other than having to move from the cockpit to the bow maybe one additional time, doesn't seem to be any less convenient than the 26M version. I may be missing something, but I bet when I drop mine on the deck, that winch will do more damage than your rope and blocks...
Re: mast raising system
Posted: Wed Aug 19, 2015 3:08 pm
by K9Kampers
Interim wrote:
I've been trying to thing of a way to lift the mast without the MRS (will have one helper). Does anyone know how much force is needed to get the mast moving? If helper is in the cockpit and gets the mast head-high, can I pull a jib halyard (standing on the foredeck) to lift it the rest of the way?
My other plan is to have a come-along attached to the bed of my pickup, which would avoid having to attach/detach the MRS.
--john
Pending your physical ability, one person can walk the mast up by themselves. I you have a helper, two can walk it up easier and safer than your proposed push / pull idea.
Re: mast raising system
Posted: Wed Aug 19, 2015 6:57 pm
by Signaleer
I can see that the newer system works better perhaps, but I have only used the OEM system a few times and it has worked fine for me.
It does seem like it takes more force at the beginning, but have you ever tried to winch a jib in SF Bay?
I also can lift it myself into place, but takes some effort.
I'm going to upgrade to the newer design at some point.
Question: Can you get the head-stay as tight with the new system pulling from the 'middle' of the mast? I would think pulling from near the head stay, above where the uppers attach, would be more effective? Logically, I'm above the spreaders and pulling the mast in a more 'straight' position ... If I am pulling from the middle of the mast, below where the uppers attach to the mast, I'd be pulling and inducing bend... I know everyone uses it, its just a question is does it matter? Can one system get something tighter vs. the other?
My rig is pretty tight (I think) and would like to make sure I am within tolerances on the tight side...
Here's a pictures of mine with the OEM system
Ed.
Re: mast raising system
Posted: Wed Aug 19, 2015 7:11 pm
by Catigale
K9Kampers wrote:Interim wrote:
I've been trying to thing of a way to lift the mast without the MRS (will have one helper). Does anyone know how much force is needed to get the mast moving? If helper is in the cockpit and gets the mast head-high, can I pull a jib halyard (standing on the foredeck) to lift it the rest of the way?
My other plan is to have a come-along attached to the bed of my pickup, which would avoid having to attach/detach the MRS.
--john
Pending your physical ability, one person can walk the mast up by themselves. I you have a helper, two can walk it up easier and safer than your proposed push / pull idea.
I still walk mine up single handed , but I confess I hope to get/fab a MRS for next birthday...that sure posted funny
Re: mast raising system
Posted: Wed Aug 19, 2015 7:15 pm
by Jimmyt
With the winch mechanical advantage, pulling at 6 ft up, you could probably buckle the mast if you got carried away. Since you are trying to tension the stays, pulling at the top might be better for safely applying tension. It is my understanding that the M rotating mast is not rigged as tight as the others (to allow free rotation), so maybe that explains the different design - although many use the new system on other boats.
Mine got bound at the mast base somehow once and I couldn't find any rigging issues, so I cranked on the winch. Whatever was stuck (maybe a burr on the mast base) let go rather violently. Nothing damaged, but alerted me to be careful with the raising winch lest I destroy something.
Re: mast raising system
Posted: Wed Aug 19, 2015 7:38 pm
by Jimmyt
Catigale, you're gonna change the rating of the site with talk of walking yours up single handed, and fab'ing a MRS for your next birthday... Will she be an inflatable? Are you going into production? It did post funny, and I almost spit out perfectly good beer laughing at it - thanks!