Trim tabs on my .45 speedmaster

[Sean Bowf]

Ok...I was in chat, and some guys running gas monos mentioned putting the trim tabs 1/16 off the bottom of the hull. I don't know why...but I figured they had to be flush with the bottom of the hull (thought I read that some place, but now I can't find it in the instructions (they dont mention the tabs at all...other than being in the parts list)...other than the pic, which appears to show them flush with the bottom of the hull). Anyhow...so, on a .45 speedmaster mono, are the tabs supposed to be flush with the bottom of the hull, or are they supposed to be a little higher??

Also, I think I mounted the trim tabs with the adjustment plate upside down...I guess it will work just as good...and I already cut a notch in it to go around my rudder bracket, so it will have to stay until I get some new ones... Anyhow, pic attached.. upside down or no?? Will it mess up how it runs??

What is a good starting point for the angle of the tabs?? Even with the bottom, bent up a little, or bent down a little??

Thanks in advance for your help,

Sean

 

[Glenn Quarles]

Sean, the belief is that by having the tabs mounted slightly high the drag will be reduce by allowing the tabs to "ventilate" a little. I have run them both high and flush and haven't seen any noticeable difference.

Yeah the adjustment plates are upside down. It shouldn't be a big deal if the plates go "up" enough to get the boat trimmed properly.

I would start with the tabs about level.

Hope this helps some,

Glenn

 

[Ron Olson]

Sean, you might find that the boat doesn't need the trim tabs. You'll find out for sure once you get it in the water.

 

[waltr]

Hi Sean,

I just finished building my 45 Speedmaster and can't wait for the ice to thaw and get this baby wet!

We'll see how it runs against my Seaducer, but I really, really like the boat.

As far as the tab location, yes, they DO need to be up that 1/16".They create noticeable drag if they're even with the bottom.They need that small air space to ventilate.

The same principal applies to our big Skaters, cats and Vs. Lots of testing was done and many documented MPH lost with tabs even with the bottom. In the big boats, the tabs are mounted 1/2"up.

And yes, mine are 1/16" up on my Speedmaster.