Permatrims: My 2 cents

[daninPA]

[thataway]

[ssobol]

[C Sniper]

So I finally got a tomcat, which I have been dreaming/drooling over for a few years. I starting looking a boattrader and here daily, some times twice a day... and boom one popped up in PA. Fast forward, have been using her mainly as my work boat for a few weeks, figuring out the nuances and such. I have read that permatrims on the tomcat are not as helpful as on the other C Dory vessels. Working, I am regularly out in 20-30 kt winds, always finishing the day smashing up wind into estuary chop. So any thought from those who have tried them in similar conditions? I would say the 20% smoother ride would motivate me to pull the trigger.

[thataway]

I put the Permatrims on our Tom Cat 255 to see if I could plane and get the stern up at a slower speed, because of similar concerns.

Although I feel that they are almost essential in the monohulls, I don't think that they help much, and may be slightly detrimental on the Tom Cat.

We found that speeding up and keeping the boat light was the best "solution" for going into the 2' chop. The Suzuki outboards definitely give a faster top end speed. We were running very close to 50 mph with the 150 Suzuki outboards and as I recollect 21" pitch 4 blade PowerTech props.

[T.R. Bauer]

A good part of the reason the TC 255 rides so nice and is very efficient at speed is the air cushion (and lift) that is created from the cat hull design. I love the concept of permatrims in general - great product. However, I can see why one would not have the most favorable results with them on the Tomcat as they could contradict the inherent benefits of the hull design. Bob said they may even be detrimental and I believe him - makes complete sense. None the less, I'd love to have a TC 255 in my small fleet...even one with permatrims

[Molly Brown]

We have the TC24....The hull deck is too low for that "air cushion" to work well. You definitively want permatrims on a TC. Same hull as the TC255, granted it is bigger and set up differently, but you'd be hard pressed to convince me the permatrims are not effective on just about any boat that planes.

Just my 2 cents

James

[thataway]

It is a very rare day I would disagree with James. But there is enough difference in the boats which I believe makes our experiences different,

The difference between the 255 and the 24 is the engine bracket. The 24 has the engines mounted directly to the hull. The flow of water at the end of the bracket in transition from displacement to planing has increased turbulence, because of this bracket. I was trying to get the boat to plane at a lower speed, and we ended up with a significant increase of water coming over the bracket with the Permatrims as we slowly transitioned from semi displacement to planing mode.

As the boat came up on a plane, the Permatrims worked as in monohulls or a cat which has the motor mounted to the hull. I did not feel that the Permatrims gave a decrease in the lowest planing speed. The Permatrims decreased the top speed a small amount. This is with the Suzuki 150's which I feel are the best engines for the TC 255. Speeds with these engines and the type of props they use (4 blade, stern lifting, higher pitch), are higher than with the Honda's.

We live up near the head of Perdido Bay--there is about 12 miles of fetch during a "norther"; Winds up to 50 knots. As we left the ICW the waves were close to 3 feet. The only way to successfully get up the bay with minimal discomfort, was to take the speed up to over 35 mph--to get this air cushion increase. The 4 blade props and "reverse" (Counter rotation engine on Starboard) engine mounting all help to give more stern lift.

I agree that the tunnel height of the Tom Cat (either 24 or 255) should be about 6" higher. You have a lot of experience in the 24. I have only driven one a few times. So I certainly believe your experience is valid for the TC 24.

[B~C]

I had Doel fins, a permatrim type outboard attachment, on my twin hondas and later added trim tabs. I ended up giving away the Doel Fins. I found that I didn't need the fin gadgets to trim the boat. I can trim the boat with the trim tabs and then trim the outboards to to run at their most efficient trim.

[thataway]

The plastic fins, such as the Doll-fins do not do as good a job as the Permatrims. One can "trim" their boat any number of ways. The goal is to give the best ride in all conditions: especially into chop--the weak point of the C Dory line. The Permatrims plus trim tabs on the monhul C Dory boats appear to do this. There are other benefits, such as in monohulls being able to plane at an even lower speed.

My first 22 had no trim tabs or foil. My first 25 had trim tabs, and after running it for a few months, I added the Permatrim. So my opinion is based on using a boat with no trim devices of any sort, in comparison to a boat with trim tabs only and then both a 22 and two 25's with the foils. I had one boat which came with the Doel-fin, so was able to compare with Doel-fin and Permatrim.

All of this is somewhat subjective, so persons' opinions may vary.

[T.R. Bauer]

I have had trim tabs, doelfins, and whale tails on various boats. They all do something. The hydrofoil (SE Sport I think plastic thing) on my ski boat long ago made some difference - it would get on step with a boat full of people and pull a skier with relative ease. Before....yeah...but it took forever and was harder to get the skier up. I remember I lost some top speed, but I'm not completely sure because I put a 4 blade prop on it at roughly the same time.

The Davis whale tails on my 22 with twins drastically changed the boat - for the better. It hauls weight easier, planes a bit slower, and they created an unexpected amount of lift on the stern which puts the bow right into the waves. I was actually shocked at the difference. Fuel consumption didn't change either, nor did top speed. If it did, it is not perceptible after having them on the boat for hours upon hours. I'm sure the permatrims do as well - probably work better actually.

[C Sniper]

Hopefully my hondas will last a long while (fingers crossed). I keep my vessel expedition-ready with kiteboarding lesson, fishing, spearfishing and diving gear always loaded. So light is out of the question. I will have to try speed = air cushion more to better understand how that works. Thanks for all the comments thus far.

If I put on permatrims what size/model is suggested? I went to the website recently and it was not clear briefly reading their suggested uses which ones to go with. Suggestions please.

So if I do put on permatrims on the future, and don't like them, what do I patch the holes with when they are removed. Guessing JB weld has some metal in it which might increase aluminum oxidation on lower unit???

[C Sniper]

Also any thought on whether they would allow for hole shots in shallower water than without them? The lower laguna madre (my inshore waters) has lots of very skinny areas. Seems like my TC needs 30-36 inches to get going. Any tips on shallow water starts appreciated. Can't roll a cat out in shallow water, works well with a mono though.

I almost aways have a mud cloud trail following me around I have noticed...

[daninPA]

Our C22 came with 115HP Yamaha. It was stern-heavy with 1/2 tank or more of fuel (we travel light -- no overnights, equipment, etc).

After installing the Permatrim the rough water became much easier to handle. The only lesson I had to learn was tilt up when running with following seas.

[thataway]