Mast Backrake

[Terry Chiccino]

Steve, thanks for the info, I've got the adjustable backstay as well. You did bring up another question.
The rigging instructions that came with the boat talks about letting the mast lean back I think it said six degrees or so, in that section of the owners manual it has a templet with the correct amount of mast lean. The manual tells you the diagram is to scale and to make a permanent templet out of plywood or something. The boat came from the dealership in Seattle (Bluewater yachts I think). The dealership has quite a bit of instruction in the form of type written pages. They tell you to put about 17 degrees of backlean in the mast. I thought that was excessive but thats the way the boat came set up. I tried to adjust that out but ran out of turnbuckle adjustment, about the best I can muster out of the turnbuckle is 4 to 6 degrees. Do you know what the mast lean should actually be, or do I just experiment? I guest the initial mast lean adjustment controls the boats tendency to turn up or fall off the wind? I'm new to sailing and bought the MacGregor to give sailing a try! Thanks Terry

[Steve K]

Terry,
Sorry, didn't see your question until just now. Don't usually check the boards on weekends.

I think the factory reccomended mast rake is around 4 degrees. The owners manual does give this number, as I remember. Rake is the lean you speak of.

If I remember (and it's been several years since I remember reading the Bluewater yachts article) Bluewater is talking inches, not degrees when speaking of mast rake. In other words, the top of the mast would be 17 inches behind the bottom, or mast step, on a level boat, when properly adjusted. This would actually be somewhere in that 4 to 6 degree area of rake. The way to check your rake this way is to attach a weight to the main halyard and hoist it a few inches off the deck, level the boat and then measure the distance from the back of the mast to the weighted end of the halyard. You need to do this when there is no wind to blow thw halyard around. It's easier to use the template from the MacX manual, because you don't need to have the boat level, nor do you need a dead calm day.

As for amount of rake, the factory reccomended setting gives the boat a good amount of weather helm. This is, in a way, a safety factor built into the rig, particularly for the new sailor. You see, when a boat has weather helm it will heel a certain amount and then turn into the wind. This causes the boat to stand back up. It also causess it to slow considerably and perhaps even stop. But for the new sailor, a good amount of weatherhelm acts like a safety valve that prevents knockdowns, or at least makes the boat automaticly recover from one, no matter what mistake the new skipper may make. So, for the new sailor, the factory noted mast rake may be exactly what one wants.

The problem with excessive weather helm is, the boat will tend not to point quite as high and may want to continually be turning into the wind. You will continually be fighting this by continually steering down. Not only is this tiring, after a couple hours of sailing, you are keeping your rudders turned at an angle to the direction of travel of the boat constantly. Keeping the rudders turned like this creates drag, which causes the boat lose speed.

So, most Xboat owners have found, from trial and error, that a lesser amount of mast rake will make the boat more neutral. The idea is to set rake so that there is a small amount of weather helm, but the boat doesn't head up into the wind as quickly or easily as it does with the factory settings. The steering also becomes more neutral and you find that the more balanced boat will sail straight across the wind, with little correction of the helm.

Again, if new to sailing, one may just want to stick with the factory spec of mast rake. This may make it easier to get out of that knock down that will surely happen. The old gust from nowhere always sneaks up on new sailors, it seems .

Hope this helps. Perhaps some of the other owners can add to this.
SK

[Duane Dunn, Allegro]

17 degrees will make the boat almost impossible to sail up wind, even the factory 4-6 is to much. Most find that something around 0-2 degrees is the correct rake for balanced sailing with a loaded boat.

Remember, this is the angle of the mast in reference to the water. Most boats don't sit perfectly level compared to the boot stripe. The cabin top is not level either. It tends to slope forward quite a bit in an empty boat as it comes from the factory. The bigger the motor and the more fuel and other stuff (ie people) you carry in the cockpit the more aft heavy the mac is. You have to set the rake with the boat in the water loaded for cruising, (ie full tanks). The heavier the back end is, the less rake you will need.

[Terry Chiccino]

Hey thank you all for the advise, I hope to get my boat in the water this weekend. Northern California has warmed up considerably this last week. I was in Santa Cruz harbor all day saturday and it got to 78 degrees in the early afternoon! We're planning to put the boat in the harbor on this coming saturday and I'll be able to experiment with the mast rake. Thanks again!

[Dimitri-2000X-Tampa]

With my 2000X, I have the backstay in the last hole (longest possible) and my turnbuckle on the forestay closed almost all the way (almost shortest possible). Anybody have any idea how much mast rake that is? Do most of the Mac veterans shorten the forestay and lengthen the backstay in order to get to 0-2 degrees of rake? I guess sailing with all your crew in the V-berth would do somewhat of the same thing. I was just curious what is the least amount of rake you can get with the stock Mac.

[Frank C]

Just guessing Dimitri, but your rake is probably 3.5 or more degrees. You really need to change length of the forestay to reduce from 4 degrees to 2 degrees. When I shortened the forestay by 4 inches I got exactly 2 degrees of rake (with turnbuckle set at mid-screw). This dictated an adjustable backstay, since it no longer reached the backstay tang. Also, the shorter forestay required all four shrouds moving to the last couple of vernier holes.

Just a rough estimate, but I'd guess that the factory stays can range only from 3.75 to 4.25 degrees.

[dclark]

Dimitri, I also have my backstay in the last hole, my forestay as tight as I can get it and still be able to pin it, and my shrouds a little tighter then they probably should be...and all that got me a lot of nothing. I probably reduced the rack a half a degree and little difference when sailing that I can tell. My guess is there is still too much rake.

I've bought turnbuckles for the shrouds and most of what I need to make a split backstay and adjuster. I haven't done it yet, but soon (still need a couple parts and some time).

The thing I hestitated on was knowing I was going to have to cut the forestay. Then brillance struck me. Well actually it was someone smarter then me that also had a Mac. He didn't cut the forestay, instead he moved the tangs up. Look at how your forestay is attached to the mast. There is a hole thru the mast with a bolt and two tangs on either side. So if you drill a hole up 2"-3" and move the tangs up, viola, reduced rake without messing with the forestay, furler and all that. So that's my plan.

[Harry van der Meer]

Dave, have you completed your mod yet?

This past weekend I measured the rake of my mast using a square positioned on the cabin top, close to the mast. I then measured the distance from the top and the bottom of the square to the mast. My math resulted in a rake of 5.2 degrees. In order to obtain a rake of 2 degrees, which has been recommended on this board, I need to shorten my forestay by about 4 inches. Will this not cause the top of the furler to hit the bolt where the forestay is connected to the mast? Also, I am concerned about interference with the jib halyard block.

I like the idea of moving the tangs up 3 inches or so. However, I am a bit concerned about weakening the mast with new holes.

[Jim Bunnell]

Just a reminder - if the top of your cabin isn't level, the reading you get will not be accurate. The degrees are to be in reference to the water.

[Harry van der Meer]

Using the black stripe as a guide, the boat sits in the water quite level. The Mac manual tells you to set the mast rake with respect to the cabin top. I agree that a correction would have to be made if the boat is not level in the water.

[Dimitri-2000X-Tampa]

Another thing I don't recall if we (as a group) have ever confirmed is whether the boat really is faster with a more vertical mast?? We know by the physics of sailing that this will reduce weather helm, but do we know for sure this really makes a difference in speed for the Mac26X? Ie, perhaps raising the CB somewhat is really the best way to avoid rounding up in gusts?

[Harry van der Meer]

I did some more checking tonight. I followed Jim's advise: leveled the boat and re-measured the mast rake with a level. Rake is now 3.4 degrees. I tightened the forestay turnbuckle completely with the backstay disconnected. This reduced the rake to 2.5 degrees but the shrouds were very tight. I have to adjust those to get the proper tightness and mast bend. Of course the back stay is now too short. I ordered a Johnson quick release stay adjuster which should make mast raising a little easier.

I am still confused how to meassure mast rake. The Macgregor manual tells me to do it relative to the cabin top. Bruce Whitmore's article states to do it relative to the water. The difference I measured is almost 2 degrees. For now, I stay with the water method.

BTW, I did this without the genny on the furler. My guess is that with the weight of the genny on the furler and somewhat looser shrouds, the rake will be closer to 2 degrees, which some have said is ideal. We'll see how she sails.