Seamaster Mods
 

Just bought a 40 size Seamaster at a swapmeet. The last owner removed the covering. The structure looks good, has not been crashed and repaired. Anyone have any comments on mods to the plane, sure would be the time to do them now before covering it.

Larry

RE: Seamaster Mods
 

I've had 2 Seamasters, and I can't think of a thing I would change.

RE: Seamaster Mods
 

Get a set of Lainer Mariner wing floats. They mount like "trainer " landing gear wire (order those too) you have to install the wooden block. Do a search for "seamaster engine" to see my Sea Master twin pics.

RE: Seamaster Mods
 

I´ll get an ARF ACE Seamaster to be used only on water. Ordering also a Satio .72 for it.

Is a 3 blade prop 12-6 the rec. one?

Will that size of eng require some reinforcements to the kit?

What hardware included in the kit shall I replace due to low quality? What should I replace it with?

Understand I need to reinforce the horizontal Stab, one flying wire each side enough?
Use full lenght velcro/servo tape for the small tip floats, use a golden rod for the elevator, or for all included rods? I must be missing many other things, could you help to continue my list?

Ahhh Tip floats... Remember reading to deflect them lat. some 5 deg. Which way? Front closer to the fuselage or the other way around? Any experience with that?

Many Tks.

RE: Seamaster Mods
 

I had a blast with my seamaster. In fact I want to get another, it was one of the best and funnest planes I ever had.

I converted mine to separate aileron servos. If you have no covering this is the time to do it. Also I would recommend glassing the center section of the wing. I used 3/4!QUOT! triangle stock glued in at the joint of the horiz and vert stab. Not much else done to have a great flying bird. I did eventually do some other things like build a trussed and sheeted vert stab. That too all the flex out and while at that I trussed and sheated a larger rudder. I had the only Seamaster that would knife edge all the way across the lake.

As far as the off set on the tip floats, I left the just as they were. Saw no reason to change the incidence and never had a problem.

Good luck and happy flying. BTW be sure to land that plane with a little speed. If you come in to slow the like to bounce. Fast approach and set it down let the water be the brake.

RE: Seamaster Mods
 

I suggest cleaning up the aerodynamics of the engine pylon. Add some leading & trailing edge balsa stock to the pylon to smooth it out, & cover it with Monokote (or whatever). The wider, cleaner pylon makes knife-edge flight a breeze with a 46. My current Seamaster ARF has a TT .46 Pro with a 12-4 APC prop & it has unlimited (just) vertical & horizon-horizon knife edge capability.

I have never had a structural failure with a Seamaster & I don't re-inforce the tail assembly or the center-section.

RE: Seamaster Mods
 

Tks to both of you for the good ideas.

I would like to mount my .72 eng upright. What are the dawn sides of putting it so.
So far I see them being mounted sideways or inverted...

RE: Seamaster Mods
 

One downside is increased drag further above the center of pressure (aerodynamic center) than is already the case. This will tend to increase the existing speed-sensitive pitch change.

Another downside is an increase in the pitch-axis and roll axis polar moments.

Finally -- it will look ugly.

RE: Seamaster Mods
 

Brit,

Agree on all except the last.

RE: Seamaster Mods
 

Opted to install the Eng. sideways due tech reasons and flew it yesterday.

Really a nice plane to fly. My previous ones had been a Super Sportster 120 and an Astro Hog, both on floats. Think I like this better.

The paper towel inside the servo compartment was a litlle wet, believe the rudder push rod to be the cause. I will first try to use a bit of marine grease at the push rod exit to try and seal it but really no problem at all.
Roll was great. Noticed the slip stream effect is opposite in this plane, due high engine posiition I guess.
The Satio .72 Eng provides very good power. Fuel tank a little small for it I feel, are there any other options that fit to carry more fuel?

Tks

RE: Seamaster Mods
 

I just received an old Ace SeaMaster which I believe has never been flown. (Storage has, however taken a toll). The stab was way off square; got that lined up. It is outfitted with an old OS FS series 4 stroke which I think is a .52. Now comes the time to try to fly. any advice? I am the builder, my son the flyer. He has been flying a Kadet Senior which I set up with floats, airleons, and flaps and .46 engine. I am hoping this plane will allow him more capacity for aerobatics. This is my first experience with a 4 stroke. Any ideas on setting it up?

Does anybody recommend stabilizer reinforcement?

RE: Seamaster Mods
 

I've owned a pair of Seamasters, one kit bird & one ARF. Neither had the stab re-infoirced & neither stab failed. That doesn't mean that it can't happen -- if you are nervous about it, beef it up with external struts.

The old kit Seamasters could be very heavy if not built carefully (10 lbs). If that is the case it will need a diet to perform well on an old .52 four-stroke. A modern .52 4S will work well.

RE: Seamaster Mods
 

I think a 52 4-stroke may be on the small side for a Seamaster, so areobatics would be limited, but if your son is only flying a basic trainer, it may be just as well.

Let him get the feel of the more advanced Seamaster, then decide if you want more engine in it.

RE: Seamaster Mods
 

He is actually very good at aerobatics and has been flying for 12 years (including his full scale license in a Cessna 172). He flys a Kadet Senior with floats and Super Tigre F .51, and a Great Plains Trainer 40 with an OS .46 Because we live on a lake, our most convenient flying field is right out our front door. (He lives in Boston and only flys when he comes home to visit.) We have been thinking of adding floats to the Trainer 40.

Because of our shared hobbie a local resident on the lake gave us this Sea Master which belonged to his now deceased grandfather. He nevedr flew it, but it has taken a beating being stored. Our question is whether to spend a lot of time rehabing the SeaMaster, just getting a bigger engine for it, or adding floats to the Trainer 40. The larger size is very appealing over thelake as it always draws a croud. Recently we have experimented with adding a video camera under neath and filming the flights.

RE: Seamaster Mods
 

The Seamaster is an altogether better flier than a trainer with floats. It is aerobatic & it gets off the water easily. The current Seamaster ARF weighs 7lb with a good .46 on it & it flies well configured that way. I have seen a 10lb Seamaster with a TT .46 Pro that flew acceptably well, but was somewhat sluggish for aerobatics. I suggest that you weigh your Seamaster. If it weighs more tan 7 lb, then try to lighten it (cut holes in the ply skin & re-cover it) &/or put more motor on it. The plane is worth keeping.

RE: Seamaster Mods
 

LarryD, See what you can do about re-locating the rudder pushrod. Try to bring it up along the top of the fuse instead of where it normally goes along the side. Unless the fuse is water-tight it tends to get water in through the pushrod exit. I was toying with this idea for a couple years but never got around to it. Hope you get this before it's too late.

RE: Seamaster Mods
 

How much rudder travel to each side did you set on your ARF Seamaster in order to perform good knife edges?

RE: Seamaster Mods
 

As much as you can possibally get lol.

RE: Seamaster Mods
 

Your answer does not help lol...
---

Could someone quantify to compare? I started setting the 1 inch travel either side prescribed in the manual. Last time I increased it to 1 1/2 but that has not been enough so far, it´s getting close.

RE: Seamaster Mods
 

Sorry for the short version lol.

In all seriousness though. There are several things to consider with making a plane fly knife edge.

The seamaster was not designed with this maneuver in mind. It also was not designed to do an inverted flat spin but several of us got ours to do it. A couple with disastrous results. If you do try inverted flat spin make sure you have plenty of dammit room.

Anyway. You will need to get as much throw as possible. Here are the other factors though. You have to have very good power to weight ratio. If your plane is heavy and or marginal on power it won't work, you could have 90* rudder throw and it wouldn't matter. You have to pull your plane almost more than this plane will fly through it.

Make sure your servos can handle the increased torque needed to push the control surface. The farther you adjust for max throw the more torque you have to have.

I don't know what you have for power or how much your plane weighs so this is the best I can do for you now.

You may need to stiffen up the vertical stab. When your rudder is hard over and you get any flex (which the seamaster is known for) then you loose some of the aero force you need in the right direction.

Have fun and happy flying:
Dave

RE: Seamaster Mods
 

For inverted flat spins my highly modified Astro hog with shneider floats comes to mind ....superb.

RE: Seamaster Mods
 

For knife-edge flight with a Seamaster --- go back to post #6. The Seamaster will KE very well with that simple mod. You will not need anything better than standard bb servos (Hitec HS 425, or Futaba 3004) & a good 46 engine with a Tower muffler (TT 46 Pro, OS 46 FX/AX) or an OS 50 SX (perfect).

RE: Seamaster Mods
 

tks Britbrat, I did the mod you suggested on post 6 adding a round leading edge to the eng pylon ond a triangle shaped one aprox 5/8" to the trailing one. How far fwd and aft did you extend ?
Eng I am using is a Satio .72, very happy so far. Must say the batteries are still in the front compartment.
Due time someone else finished the kit and I had to remove step by step about 7 ounces of weight he had attached to the nose section. It´s flying much better now but knife edge flight as I said is still in the works. ( Just started with that)
If I may ask, how much throw do you have set available for your rudder?
Did it show marked pitch dawn tendencies when doing knife edges?

RE: Seamaster Mods
 

My engine pylon is 4" in width -- I extended the pylon LE by ~1/2" & the trailing edge by ~ 1 1/2".

I have 1 7/8" of rudder throw, measured at the lower corner of the rudder -- essentially everything that I could get.

It pitches to the belly on KE flight, but it is manageable -- it is easily capable of KE figure 8's, but it won't do a KE loop (at least mine won't).

Be conservative with your elevator throws -- the Seamaster can snap with too much elevator -- you will have to experiment to find the best throw for your plane -- it is dependent on wing loading (weight) & the C-of-G location.

RE: Seamaster Mods
 

Yeah.... When I picked up the Seamaster I knew the Eng pylon had not been modified to the proper size but it was my fault for not being specific on the size I wanted.
Anyway, thanks a bunch for your detailed information, the exact thing I was looking for.