Satsloader

The Seagull vs. Vmar thread was getting so long and topic bouncing, so I thought I'd start a post with "building specific" tips on the Seagull. I don't think the PC-9 will replace the Mustang as the most seen model at the field , but with it's popularity increasing this should provide a good pre-build reference. With that in mind, I would like to request that we stick to building tips ( arguments, rebuttals, and the like regarding such tips are welcome, but lets keep it about building, Okay? ).

I was lucky enough to buy my kit recently, after reading the woes of others in the past post's regarding the PC-9. These are the !QUOT!Enhancements!QUOT! I've included on my Seagull..

1. 2-56 Carbon fiber tubes for pushrods ( From Central Hobbies, cool titanium ends).

2. Du-Bro 2-56 safety lock quick link clevises and ball swivel type for the servo termination ( sorry I cant remember what Du-Bro calls them, they are the ones with the brass swivel ball ).

3. Robart control horns ( I should have ponied up for the deluxe ones with a brass swivel, I didn't see them until I mounted the all nylon ones I got. I epoxy the mounting screws into place when mounting horns so I'm stuck with them. My concern is that the nylon swivel ball pops out with decent pressure, and will get easier with repeat events. In retrospect I would go with a standard control horn here if I were to do it again ).

4. My fix for the elevator is to use a small piece of the cf tube mentioned above, and install it in the 2 elevator sections right behind the piano wire that came with the kit to couple the elevator halves. This requires that you do 2 things, drill the holes for the cf tube into the elevators nice and straight, and cut a relief !QUOT!notch!QUOT! in the rudder to clear the cf tube when the rudder is deflected. Obviously you want to keep the tube as close to the piano wire as possible without touching it. Mine is approx. 1.5mm away from the piano wire. This simple mod made the elevator much stronger!

5. I added flaps by cutting the strip ailerons and installing mini servos for them. Very easy mod..

6. Swapped out the stock fuel tank for a Sullivan 8oz. slant flex tank ( I wanted to put a 10oz. in but Sheldon Hobbies was out of them ). The 8oz tank worked very well as I was able to heat it with my heat gun and reform it to sit even lower in the plane without cutting the cross-member. I hot glued thin "Mouse pad" to the tank where it comes into contact with the plane to isolate it.

7. Epoxied the inside of the firewall edges where they meet the fuselage, rear wing mounting plate and wing dowels, and fuelproofed the fuselage interior to aft of the wing.

8. Modified the main gear piano wire so that the vertical !QUOT!leg!QUOT! of the gear is forward an inch. This required installing a basswood block against the front of the forward gear block, and cutting a diagonal groove for the piano wire to sit in ( Which means you need to be a good surgeon with the Ultacote. Using a NEW Exacto blade, cut along the inside of the ribs from the original!QUOT!gear groove!QUOT! to an inch forward of where the basswood block will mount. Then carefully pull the rear of the Ultracote up where the original !QUOT!gear groove!QUOT! is, being careful not to tear it. Your doing this to get access inside the wing to install the basswood block. Install the block, cut a new diagonal groove for the gear, reposition the Ultracote and iron it into place, then install a new larger piece of matching Ultracote on top to secure. If you don't want a leading edge !QUOT!Buck!QUOT!, then you could install the patch before laying down the original cut Ultracote back down ). I also have some nice 2!QUOT! wheels that replace the stock ones.

I have Robart struts that will go onto her after some first flights ( straight's for the mains, 651 for the nose, pivots facing forward ).

As for the beautiful cowl, Using a Dremel I opened up the inside of the exhaust ports to make them function as heat relief. I've heard that positive pressure builds up in there, and hope this will help. I also used a gold "Sharpie" and dabbed on a sparse layer onto the exterior of the exhaust stacks, then after a day coated them with a thin layer of epoxy to fuel proof. It looks very nice! The black exterior of the exhausts just looked wrong to me. I also used a black Sharpie to color the interior where I dremeled, then sealed with epoxy as well. I finished by using a red Sharpie on the white trailing edge of the cowl, which was visible when installed on the fuselage. It matched perfectly. If I can get my digital camera to work I'll follow up with a pic or two.

I'm sure I've forgotten a few other things, will follow up as needed.

BTW, the "One hour to assemble" doesn't apply here. I'm slow and somewhat anal about things, and have about 40 hours into her. Time well spent I feel..

So,

What do you think, and what can ya'll add?

Sincerely,

Bill in Pacific Grove, CA.

Satsloader

Sorry about the quot!____quot! that ended up in my post. I used spellcheck and copied/pasted, didn't realize it wouldn't translate the quote function. I'll just do corrections the old fashion way in the future..

Bill

da50ex

Bill,
Sounds great. Pretty much all the improvements that I had done, but rather than springing for carbon rods, I just used the supplied rods and ran the ends through guide tubes where they exit the fuse. I had a .61 in it and never had any flutter problems. I'm curious as to hw your aileron response will be after cutting them for your flaps. I used flaperons through mixing, but after a few flights, never used them as it sets up a nice stable final approach without them. What ebgine are you using?
John

Satsloader

Hi John,

I've got an O.S. 46FX that I bought 10 or so years ago and never used that will go in it ( Moved from San Diego to the Monterey area back then and haven't flown since then ). I was going to use my trusty old 46SF, but upon pulling it apart recently I found a bit of rust in the rear bearing, so am ordering some Boca high performance bearings for it. I moved the carb from the SF to the XF though, I'm not a fan of the remote needle set up. Also a member of the skinned knuckle club .

I got some small diameter carbon arrow shafts from the 84 olympics back when I was flying and put them in a Royal 46 size Bearcat. They were so smooth that I decided to always use cf tubes and good linkage from then on. Today's cf tubes are lighter than the arrowshafts were. The 2-56 type with the titanium ends from Central Hobbies are unbelievably light. My electronic postal scale only measures in 1/10th ounces, and a pair of 35" tubes with the ends are 6/10th oz.

Fiber CA hinges were new to me, and had I to build this plane again I'd probably open the slots a bit and install good nylon/metal pin hinges instead. I don't plan on doing alot of high G manuvering at speed, but the thought of cycle fatigue on CA hinges bothers me. I didn't know about the crayon trick, but I did work the hinges while the CA was drying so they're good and flexible.

The flaps are 9.75" ( Ailerons are 14.25" ). While this means I will have less aileron action, my flying style is more scale like so I think they will work well.

BTW dry weight with the stock landing gear is 5lbs., 12oz. ( with a Dave Brown 2.5" spinner, APC 12x5 prop, and 1/2" carbon strips epoxied on the bottom of the wingtip end ribs for some runway scrape protection ). It's a bit heavier than I'd hoped for, but the flaps will help in this regard. I also mounted a 1"control horn on the lower rear end of the fuselage to protect the rudder on less than perfect flairs. 3/4" would have been a better choice here though. I'll trim it. I've got the receiver antenna in a clear nylon tube on the underside of the fuse, and the end of the antenna slips into the control horns holes to secure the last inch or so.

I bought a Futaba 7CAP for this plane, as my old radios were.. old.. Right now I've got the surface movements as suggested in the Seagull instructions. I set up dual rates on the flying surfaces with 20% expo on low and 40% on high. I also have the CG right at 80mm from the leading edge as directed in the instructions. Given that I've moved the gear forward ( I couldn't believe how much energy it took to push the tail down with the gear in the stock position.. I need a bumper sticker that says "Got Long runway?" ), Is the stock 80mm balance point correct? I know some aisan kits have gotten that spec wrong in the past.

Thanx for any feedback or suggestions..

Bill