I have owned a 26X since 2001 (w 50 HP Merc). The boat has always seened heavy in the stern, even with the batteries moved forward. I recall reading somewhere that hydrofoils on the motor are not recommended on the Mac, but I wondered if anyone has ever tried them to help bring the bow down while under power?
(Search terms hydrofoil, doelfin, dolefin, dole, doel, stingray, sting)
Motor Hydrofoils
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Billy
- First Officer
- Posts: 439
- Joined: Tue Jan 06, 2004 3:50 pm
- Location: Dunn NC 2001-26X140 "XX"(DoubleCross)
I used a set of transom wedges to "tuck" my engine a little more under the stern. I've heard of 2 sets being used, but that might be going just a bit far.
If you're not familiar with these, here's a link:
http://www.bobsmachine.com/Products/transom_wedges.cfm
If you're not familiar with these, here's a link:
http://www.bobsmachine.com/Products/transom_wedges.cfm
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MAC26X
- Chief Steward
- Posts: 89
- Joined: Fri Dec 31, 2004 12:57 pm
- Location: Sandusky, OH 2001 Mac26X Anne Marie Honda 50
I put the transom wedge on several years ago. I thought tipping the motor down would raise the stern for better performance. You can get the bow lower (stern higher) with the wedge but I wouldn't bother doing it again. I still find I get max RPM and speed under full power when I raise the bow higher using the trim. The best solution is a raised helm seat.
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Duane Dunn, Allegro
- Admiral
- Posts: 2459
- Joined: Fri Jan 02, 2004 6:41 pm
- Sailboat: MacGregor 26X
- Location: Bellevue, Wa '96 26x, Tohatsu 90 TLDI and Plug In Hybrid Electric drive
- Contact:
I put them on my 50hp Tohatsu. They made no difference. Even with the motor full down there was no change in the running angle. I took them back off. As it's been explained to me the X never really reaches a speed where the develope any significant lift. Because of this, all you get is more drag and no benefit.
Spend your money on a seat mod or a hump cushion to get better visibility forward. You are never going to get the aft end of the boat out of the hole with a 50hp motor. You just have to live with our plowing not quite on a real plane position.
Spend your money on a seat mod or a hump cushion to get better visibility forward. You are never going to get the aft end of the boat out of the hole with a 50hp motor. You just have to live with our plowing not quite on a real plane position.
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Frank C
I doubt there's a uniform answer for the question of the bow-high issue, since each outboard choice makes a different boat. Wedges definitely will enable more trim-in, but its usefulness probably varies with the performance of the different outboards - and is probably most useful with larger props and higher horsepower.MAC26X wrote: ... wouldn't bother doing it again. I still find I get max RPM and speed under full power when I raise the bow higher using the trim. The best solution is a raised helm seat.
Trimming-in results in a less direct thrust vector, so it requires more power. It is effective when there's enough power to push the hull over the bow wave and help to lift the stern up onto plane - after which it's best to trim-out again, improving the thrust vector. Since the 12-inch 50s have barely enough power to break onto plane, it's not surprising that trimming in might actually impair planing.
Last edited by Frank C on Sat Jun 03, 2006 1:12 pm, edited 1 time in total.
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Dimitri-2000X-Tampa
- Admiral
- Posts: 2043
- Joined: Fri Jan 02, 2004 5:36 am
- Sailboat: MacGregor 26X
- Location: Tampa, Florida 2000 Mercury BigFoot 50HP 4-Stroke on 26X hull# 3575.B000
When I bought my boat 3 years ago it had the hydrofoils on it, it also came with 150# of extra weight in the bow. All this did was slow down the boat and make it less stable. Once when by myself and raising anchor, the boat got into some unstable oscillations which really made me wonder about the design. I took the weight out and it never happened again. When I took the foils off, I got a slight increase in speed so I left them off too. The hull is designed to be in a nose higher attitude while planing than conventional powerboats.
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ChrisNorton
- Engineer
- Posts: 132
- Joined: Fri Mar 11, 2005 6:54 am
Manual says no. I don't condone adding them (so if you do and die don't sue me.)
Having said all that, I added Stingrays (one piece, greater foil shape) this year and have a report. I previously had dol-fins (two piece, less of a foil shape) on my other fishing boat.
They do make a difference (at least with my heavy as hull Merc 50hp bigfoot.) They lower my bow at all speeds. I know from how many pillows I had to stack on the helm seat prior to installation, that they lowered my bow by two pillows.)
I would guess that is about a foot (not sure about degrees.) It seems like they cost me about .5 - 1 mph at top end. At slower speeds, the bow is much lower than without them. By changing the angle of the motor, I can produce a huge change in nose up or nose down attitude.
That brings me to some important points. When draining the ballast tank (I have a 99X), I force the nose up by tilting the motor up a bit. This ensures the tank empties (having the boat too flat to fully drain the ballast tank is one of the reasons Macgregor discourages their use.)
Second, I have detected a bit of instability when at high speeds in rough waters. Catching a wave on the side at speed can catch the foils and push you over a bit. In flat water, no instability was noticed. The instability was noticable and managable but I could see it causing a bit of a problem under certain conditions. This is another reason Macgregor discourages them.)
Thirdly, Macgregor claims the forces these things put on the cavetation plates of motors can snap them off. I don't buy this, at least not with my Merc which has a thick cavatation plate. The nuts will strip the bolts before the cavatation plate cracks off. I used the dol-fins on my fishing boat for 10 years with great results (5mph more speed and awesome planing.) However, that was a deep V hull that was meant to plane.
Will I keep them on the boat? I think so...at least for this season. While I lose a small amount of top end speed, I really like the flatter profile on the water. I don't like the slight instability in rough water (3-5 foot waves) but I'll solve that by slowing down a tad when the waves are big and not let the auto-pilot run without me at the wheel.)
IMHO, I think the Stingrays have more foil shape and hence more lift than the dol-fins so they give noticable improvement for the Mac. I would bet the dol-fins do next to nothing for the Mac.
BTW, there is a very clean 2000 X for sale in my marina (Stamford, CT outside NYC.) No price and the boat has 0 extras on it but it is in like new shape. It has a Honda 50hp on it. I bring it up because the one extra the boat has are dol-fins on the motor.
Having said all that, I added Stingrays (one piece, greater foil shape) this year and have a report. I previously had dol-fins (two piece, less of a foil shape) on my other fishing boat.
They do make a difference (at least with my heavy as hull Merc 50hp bigfoot.) They lower my bow at all speeds. I know from how many pillows I had to stack on the helm seat prior to installation, that they lowered my bow by two pillows.)
I would guess that is about a foot (not sure about degrees.) It seems like they cost me about .5 - 1 mph at top end. At slower speeds, the bow is much lower than without them. By changing the angle of the motor, I can produce a huge change in nose up or nose down attitude. That brings me to some important points. When draining the ballast tank (I have a 99X), I force the nose up by tilting the motor up a bit. This ensures the tank empties (having the boat too flat to fully drain the ballast tank is one of the reasons Macgregor discourages their use.)
Second, I have detected a bit of instability when at high speeds in rough waters. Catching a wave on the side at speed can catch the foils and push you over a bit. In flat water, no instability was noticed. The instability was noticable and managable but I could see it causing a bit of a problem under certain conditions. This is another reason Macgregor discourages them.)
Thirdly, Macgregor claims the forces these things put on the cavetation plates of motors can snap them off. I don't buy this, at least not with my Merc which has a thick cavatation plate. The nuts will strip the bolts before the cavatation plate cracks off. I used the dol-fins on my fishing boat for 10 years with great results (5mph more speed and awesome planing.) However, that was a deep V hull that was meant to plane.
Will I keep them on the boat? I think so...at least for this season. While I lose a small amount of top end speed, I really like the flatter profile on the water. I don't like the slight instability in rough water (3-5 foot waves) but I'll solve that by slowing down a tad when the waves are big and not let the auto-pilot run without me at the wheel.)
IMHO, I think the Stingrays have more foil shape and hence more lift than the dol-fins so they give noticable improvement for the Mac. I would bet the dol-fins do next to nothing for the Mac.
BTW, there is a very clean 2000 X for sale in my marina (Stamford, CT outside NYC.) No price and the boat has 0 extras on it but it is in like new shape. It has a Honda 50hp on it. I bring it up because the one extra the boat has are dol-fins on the motor.
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ChrisNorton
- Engineer
- Posts: 132
- Joined: Fri Mar 11, 2005 6:54 am
What about trim tabs? AS long as I have been studing and reading everything I can find on the mac powersailers, no one has ever said they have tried trim tabs , I am talking about the type that attach to the bottom of transom. My brothers bayliner had them and it made the difference between plowing along at 12 mph and a real planning attitude at over 20 mph. have seen then used with great results on 35+ft sport fishing rigs.
A search reveals that the question was raised before, oct 2004 by nyharleyrider and never answered by anyone who had tried this or knew of trim tabs being used on a powersailer. The thread turned to use of foils. http://www.iboats.com/mall/index.cgi?prod_id=24438
Above is what I am talking about. I can t afford to test them , don't really know if there is room enough on the transom.
Tom, 96x merc 50 BF Son Of a Sailor
A search reveals that the question was raised before, oct 2004 by nyharleyrider and never answered by anyone who had tried this or knew of trim tabs being used on a powersailer. The thread turned to use of foils. http://www.iboats.com/mall/index.cgi?prod_id=24438
Above is what I am talking about. I can t afford to test them , don't really know if there is room enough on the transom.
Tom, 96x merc 50 BF Son Of a Sailor
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Frank C
I've pondered the trim tabs many times during afternnon browsing at West Marine. You've already cited the major problems.
1. I doubt there's anyplace on my transom they'd fit.
2. I wonder if they'd interfere with sailing efficiency as much as they might assist in motoring.
3. the real trim tabs are $600 to a Boatbuck - too much to just "take a flyer" on a whim. The "automatic" one's you linked are lots less expensive, but they would DEFINITELY impair performance under sail since they're intended to hang down at all lower speeds.
4. Someone (Volvo marine?) has just brought out a patented design that DO extend below the transom to create intentional drag, but are also retractable. They are the most expensive I've seen, especially for a device as braindead simple as it looks. If the job jar wasn't already so full I might take a stab at a DIY version.
1. I doubt there's anyplace on my transom they'd fit.
2. I wonder if they'd interfere with sailing efficiency as much as they might assist in motoring.
3. the real trim tabs are $600 to a Boatbuck - too much to just "take a flyer" on a whim. The "automatic" one's you linked are lots less expensive, but they would DEFINITELY impair performance under sail since they're intended to hang down at all lower speeds.
4. Someone (Volvo marine?) has just brought out a patented design that DO extend below the transom to create intentional drag, but are also retractable. They are the most expensive I've seen, especially for a device as braindead simple as it looks. If the job jar wasn't already so full I might take a stab at a DIY version.