trim tabs

007joe · 01-03-2008, 08:23 PM

couple of questions for you guys, i notice on some boats tabs are mounted horizontally and some are even with the bottom of the boat parallel to the actual v on the bottom what is the correct way to mount? also how difficult are tabs to mount in general, just drilling and some hoses/ wiring or am i nuts?

007joe · 01-03-2008, 08:26 PM

looks to me like horizontal would be more efficient

Griswald · 01-03-2008, 08:42 PM

I have been told mounting them horizontally will help a boat that chine walks without pushing the nose down. Increasing tab will only allow the outside corner of the tab into the water allowing more stability side to side.

Makes sense to me when I think about it. Am I and the person that told me crazy?

MOBILEMERCMAN · 01-03-2008, 11:21 PM

The short answer is they are relatively easy to install. For many years Velocity mounted tabs at 1/2 deadrise and installation instructions with kit recommends mounting even with bottom.
Recently, increasingly more people and companies are mounting them horizontal on the faster boats.

As with many things related to boat set up there are different schools of thought and a lot of follow the leader trends.

It seems the function of trim tabs has expanded from assisting in control of the boats attitude to include help in reducing chine walking.

Griswald · 01-04-2008, 07:47 AM

Jim, I just realized you're in Austin. Where do you live? I'm at the far north end of Sandy Creek in Jonestown.

Audiofn · 01-04-2008, 09:08 AM

Don't put them even with the bottom of the boat if you got that route. You want them up about 1" so that when they are in the up position you do not have all the drag.

MOBILEMERCMAN · 01-04-2008, 09:27 AM

Audiofn and Joe,
sorry i wasn't clear. " at angle angle even with bottom up 3/4 of an inch is what is suggested." That has long been the norm but not so much any more. I personally like the 1/2 deadrise on outside corners myself.

Griswald,
I'm am pretty close to you, I am off Anderson Mill in NW. I find myself in Jonestown frequently during the season and would like to find the right piece of property there somewhere.
I have contact info in my sites found in profile.
I'm always eager to meet avid boaters.
Best wishes,

rchevelle71 · 01-04-2008, 10:28 AM

On the shorter boats I like them at the same angle as the bottom, since this effectively lengthens your running surface. If i was out for all speed, and very little control, or had a longer boat with big K-planes then I would mount them horizontally.

Jim, when you say "half Deadrise" I assume you mean horizontally level? Sorry, I am a self taught shadetreee rigger, and not in tune with the technical terms.

Rick

MOBILEMERCMAN · 01-04-2008, 11:16 AM

No, I like what Velocity has always done. By 1/2 deadrise is say 11 degrees on a 22 degree, or 12 degrees on a 24. The half to horizontal position. I use tabs with lifting the stern in mind when flying. I think horizontal is wrong. Tabs slaps the water, you lose some fine adjustment, you side load the plates and things like cylinders and pins break more often. I believe they are there to control attitude. You drive it proper to keep from chine walking.

rchevelle71 · 01-04-2008, 11:19 AM

Quote:

Originally Posted by MOBILEMERCMAN

No, I like what Velocity has always done. By 1/2 deadrise is say 11 degrees on a 22 degree, or 12 degrees on a 24. The half to horizontal position. I use tabs with lifting the stern in mind when flying. I think horizontal is wrong. Tabs slaps the water, you lose some fine adjustment, you side load the plates and things like cylinders and pins break more often. I believe they are there to control attitude. You drive it proper to keep from chine walking.

Cool,

I never thought of that

Rick