Well I have settled on a hatch technique. I will get to that in a bit, but I don’t want to get side tracked from reporting the build. It’s been a bit since I’ve updated the thread with pictures and progress. I am actually at the point where I am sheeting the fuselage and the sticks are starting t to resemble a HOG – very cool. [8D]

The fuselage came together very quickly thanks to SIG’s interlocking design – very much like a jigsaw puzzle. The first 2 elements to come together were the firewall and Former F3. I attached the firewall with epoxy and made sure it was at right angles to the fuselage. Once the epoxy cured, I CA’d F3 to the fuselage side keeping it square to the side. Next step is to repeat the process with the opposite fuselage side. Pictures 1 and 2 show these steps completed.

The next few steps happened quickly and I didn’t snap many pictures (sorry). This is where the jigsaw element really becomes evident. The instructions basically have you rubber band all formers, along with the fuselage bottom rear, fuselage top and stab support together. Once this was dry fit, I spent a fair amount of time making sure everything was square. This is an important step because once you hit the structure with CA, it ain’t gonna move. Now before I started this dry fit exercise I decided to cut holes in the bottoms of the formers in order to route an antenna tube. You can see the installed tube in Picture4.

I used Medium CA for this job and carefully started at former F5 and worked my way to the back of the plane. After each former, I stopped and checked to see that everything remained square. I did this all the way former F8. I then went an CA’d the fuselage top in place. Finally I went back over all the joints (from the inside) with thin CA and let it wick into all the joints. Pictures 3 and 4 show the fuselage at this stage.

Next up was adding the triangle supports to the firewall (picture5).

Next up – adding the fuel tank.

Picture1 – Started the Fuselage – Former F3 and Firewall in Place
Picture2 – Another angle of the Firewall and F3 in place
Picture3 – Fuselage side, once all the jigsaw pieces were CA’d together
Picture4 – Different angle of the fuse; notice the antenna tube already in place
Picture5 – Firewall supports in place

Okay, so the fuel tank setup is basically a single step in the instruction manual – however I deviated from the instructions a little on this one. Once I got the fuse together and dry fit the tank floor into place a couple things became evident to me:

1) There isn’t much room in the tank area to get to the floor or landing gear area in the event I need to get in there.
2) Looking at how the tank sits in relation to the Saito 100, the tank’s going to be too high (in its default location) in relation to the spray bar on the carb. (see Pictures 1 through 4)

So, I decided to kill 2 birds here. I went with a removable tank floor option. I sanded down the edges of the tank floor so it would fit between (instead of on top) of the fuselage doublers. Next I got some scrap balsa blocks and marked their positions on the underside of the tank floor (picture5). Using the tank as a guide on height, I slid the tank and tank floor back into the fuse to mark the proper height. From there it was easy to glue in the supports (picture6) and screw down the tank floor (picture7). I wrapped up this session by epoxing down the landing gear mount.

Next up – “the hatch”

Picture1 – Side view of the tank sitting in the default position. No Foam in place
Picture2 – Higher angle showing tank without foam. Sitting almost perfect, maybe a shade high.
Picture3 – I added foam to the bottom of the tank to see how high it raised the tank – way too high
Picture4 – Higher angle really shows how high the tank is…
Picture5 – New tank supports marked on tank floor
Picture6 – Tank floor supports CA’d into place – note I had already drilled them for attachment to floor
Picture7 – Tank floor in place (with screws)
Picture8 - Landing Gear mount

The “hatch”.

This thing has been bothering me for a week now. And I’m finally to the point of moving forward. Originally, I wanted a “screwless” option, something that would be secure, allow me into the area if need be, yet not ruin the appearance. I should have added to the criteria, and something I could build myself.

After much thought, some experimentation, and lots of RCU searches, I decided to amend my “screwless” design criteria. (When you can't beat 'em, change the rules!) I went with a single screw at the front of the tank for a little added security that things were going to stay where I wanted them.

I started this little custom job by fabricating 2 new formers, duplicates of F2 and F1A. I made them each from scrap ply from the kit (I hate wasting anything). My plan was fairly simple, add 4 ½” rare earth magnets to the F2 formers and a screw hold-down on the F1A formers. Picture1 shows how I added the magnets to F2 (note there were 2 of these).

It’s tough to explain what I did to the F1A formers – hopefully the pictures do it justice. I first cutout the original F1A so the round hole in the firewall wasn’t blocked – I planned to add a piece of balsa block above this round out on F1A as the screw support for the hatch. Next, I cut out the duplicate F1A so it would fit over the balsa block (see picture2).

I then CA’d the original F1A to the firewall and added the balsa block. I dry fit the second F1A next to this and added the balsa block to this piece (see Picture3 and Picture4). Next I CA’d the original F2 into place and shot down some kicker. When sure the CA had cured, I brought the fabricated F2 near it and the magnets snapped together. This is one heck of an attraction. I almost pulled off the CA’d F2 when getting the fabricated one off. I don’t think this is going to fly off in flight (yeah, famous last words). See Picture5 to see all these formers in place.

I decided to glue in the stringers on the hatch before completing the fuselage bottom front. Just in case I needed to glue something from underneath, I’d still have the chance with the bottom off. I ended up installing the stringers from the original F1A all the way to the end of the fabricated F2. I tack CA’d these in place (Picture6), then removed the hatch and finished gluing (Picture7). I added the fuselage bottom front, and finished adding the stringers to the fuselage top (picture8).

I really think the magnet deal is going to work. Having the tank secured at the front with a screw gives me a little more peace of mind. Yeah, it’s not exactly what I was after – but I think I’ll be able to live with it…

I will form the sheeting later tonight and see if I can’t get this Hog sheeted tomorrow and start on the tail feathers.

Picture1 – Former F2 with the magnets in place (this happens to be the duplicate F2)
Picture2 - Both F1A formers, modified for the hatch hold down.
Picture3 – F1A’s in place with their balsa blocks. A hold down screw will be added later to keep this assembly together.
Picture4 – A better view of the 2 F1A formers with their respective modifications. I placed them side by side so you could see their relationship. I drilled a hole when they were in place to act as a pilot for the hold down screw
Picture5 – Formers in place, ready for stringers.
Picture6 – Stringers tack glued in place over the removable hatch
Picture7 – Hatch removed and finished up gluing
Picture8 – Stringers completed – ready for sheeting

Great thread MA. Just want to give you encouragement to keep posting!

Some days you get the bear. Some days the bear gets you. And some days (like today) the bear doesn't come outa the woods

Thanks SeamusG! I just prepped the sheeting and its starting to really look like a Hog now. In the morning she'll be ready for the sheeting to get attached. Almost time to really start thinking of covering schemes.

-MA

MA - I also used the 14oz dubro and it appears that my tank height is perfect. The round plug on the tank lines up perfectly with the hole in the firewall. I only put foam on the sides of the fuel tank and not on the top or bottom. It worked out to be 1.5" of foam on each side and it sandwiches the tank in there perfectly w/o resting on the tank floor in the fuselage.

Hey MA,

I've been trying to put together a construction "best practices" document (cause I have a short memory) ...

What kind of glue do you use to join two pieces of balsa sheeting? CA? Alphatic resin (Titebond / Elmers)? Cellulose-base (wood airplane glue)? Other?

I get a better night's sleep if I learn something new each day.

I'd use Titebond to join balsa sheets (to make a larger sheet). It's much easier to sand.

-MA

MA, I've been watching your thread. The plane looks great so far. I'm not ready to tackle a bipe, but plan to start a Great Planes Rapture 40 soon.

Rumor (and some personal experience) has it that wood modeling glue (like Ambroid and Sigbond) sand a bunch easier but it has less strength (and it SMELLS . And it dries much faster. I'll try using Titebond on some test material.

Thanks.

MA,

Did you move the landing gear plate forward at all or did you modify it in any way? I'm thinking of moving mine forward 1/2 inch as I fly off grass and the field is sometimes rough and can get a bit long between mowings. I plan on doing this to avoid nose overs.

I'm watching your build closely as I have just finished up the top wing and am starting the bottom wing tonight (I like you, am building the wings before I build the fuse).

Thanks for the great build documentation!

Scott.

Moving it forward is probably a smart move. I've put a wedge under the back edge of mine to tilt it forward, which helps. Also, I installed a 16 oz. tank (just cause it fit, I guess). I'm going to take it out and put in a 12 oz. which is way plenty with an OS91 four stroke. I'm going to move some equipment back to try and get the cg near the back limit. My hog is just on the verge of flattening out the spin. I'll probably dink around to where I get it to flat spin right into the ground.

Jim

I did not. I felt that moving it forward might not be the best move for me. I believe RCKEN said in HOOKEDONRC's hog thread that his 3 have never had the landing gear moved forward. Honestly, I felt that it was going to be too much of a pain for the perceived gain. I suppose if I have troubles on my grass field, then I'll do what JimT did and put a wedge underneath. I did not go with the stock gear however - that was an easy change to make. I purchased the Du Bro Super Strength landing gear [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNM65&P=ML](link)[/link].

You'll have to make up your mind on gear position fairly soon as that step is coming up for you Scott. It sneaks up on you.

-MA

When I last posted on the build I had just prepared the plan for the fuselage sheeting. I rough cut the 4 sheets to match the dimensions of the stringers and then wetted the sheets. A little blue painter’s tape and it was ready for an overnight sit (picture1).

When I got to the project this morning, I removed the dry, shaped sheeting and started with the hatch. I opted to do each side (like the instructions called for) instead of creating one large sheet and putting it on all at once. For me, the way SIG recommends is easier… once I finished the hatch (picture2 and picture3), I moved onto the rest of the forward fuse and sheeted it, just like I did the hatch. This method does require careful measuring so your sheets match up in the center, but I find it easier to lay down the glue. I opted to use medium CA for these tasks. The holding power meant I could “glue n go”. Just remember to keep the CA on the inside as it’s a bear to sand.

I used a slightly different technique on the back sheeting. The very back (toward F8) gets very narrow and difficult to bend (even after the sheeting was formed overnight). I opted to lock down the bottom of the sheeting on the fuse side first (picture5). Once the CA cured, I went back in, added CA to the stringers and formers and folded it down onto the structure. This method kept the bottom of the sheeting from pulling free and causing a major pain. Okay, this is really starting to look like a plane now!


Picture1 – Sheeting wetted and strapped on with tape
Picture2 – Completed hatch, viewed on the fuselage
Picture3 – Completed hatch, off the fuselage
Picture4 – Completed forward fuselage canvas
Picture5 – Back sheeting bottom CA’d into place on Fuse side. This technique worked well.
Picture6 – Sheeted fuse (hatch removed). You’ll notice I already added some filler in problem spots, and cutout the cockpit area

Next up is what SIG refers to as the “Cowl Filler”. Okay, doesn’t look like much of a cowl to me, but …

You start by gluing some 1” wide balsa to the cowl cheeks and a cross piece just in front of the firewall. These are reinforced with triangle stock resulting in what you seen in Picture1. Once this all cures, it’s time to make balsa dust. I started with my razor plane which worked okay; the problem was the harder triangle pieces at different grain angles really kept the razor plane from doing much on the back end. Out came my trusty dremel. I slapped on a sanding drum and 30 seconds later I was in business. Just remember to stop sanding with the Dremel before you reach the desired shape, as it’s a very rough sand. Before long, I had the results you see in picture2.

The next step had me epoxy the cabane plate together. Simple and straightforward – apply epoxy, clamp together and wait.
In the meantime, I moved on to cutting open the slots on the side of the fuselage for the cabane itself. The instructions call for a ½” x ½” square cutout centered directly above the holes in the side of the fuselage. Being the detailed guy I am, I quickly make a ply jig ½” x ½” with the centerline marked. I used this to draw out the squares on the sheeting. I didn’t take any pictures of the process here. I used care in opening up these holes as I didn’t want to damage the sheeting. I carefully removed a portion of the square and then used a popsicle stick with 150 grit sandpaper to do the rest. I am pleased with the result (picture3).

I wrapped up this section by installing the kit supplied pushrod tubes. I struggled with this, only because I wasn’t sure I wanted to go with the kit supplied hardware. I figured, if I have trim issues in the summer then I’ll change out the inner rods to something metal. Either way, the black outer tube got cemented in…

Tomorrow starts the alignment of the bottom wing.

Picture1 – Cowl Filler before sanding/shaping most of it away
Picture2 – the “after” of picture1
Picture3 – Cabane cutouts with cabane struts inserted to make sure the holes lined up
Picture4 – Completed fuselage with cabane struts to dress it up
Picture5 – Couldn’t resist – had to see what it looks like with the top wing on…
Picture6 – Pushrods installed (I am going to use the kit supplied pushrods – I hope I don’t regret that decision).

question:
and if you will regret, can you just install something insted the white nyrods?
i got them too for my 4*60, im thinking if to install them at all.


Nice work by the way!!!

thanks
Alex

I assume you don't need a pump with a 4 stroke on a hog. Is that correct? TIA Fred

Correct, there is no pump needed.

-MA

MA,
I still think you are way to neat with your glue application, even if keeping it on the bottom side of the wood makes sanding easier you are just to neat and tidy with it, c'mon man squirt some CA all over it so it looks more like one of my builds
This is such a clean build you might consider a clear covering to show off your craftsmanship.

I'm new to flying and newer to building. I've picked on a local top builder that owns a LHS for advice. Gees, I have found myself sanding parts before assembly - those that ya can't get to after assembly. I've tried to use dadoes for attaching the ribs to the leading and trailing edges. It all depends on what puts a smile on your face at the end of the day!

Yea, highly transparent covering let's ya show it all off.

I'm shooting with an "anti-goop" filter on my digital camera!

Transparant covering ... I don't know. I did my mid-star in Transparent Red/Blue. I'm seriously thinking Orange/White with chord-wise black/white stripes on the undersides of the wings. I'm sure I'll change my mind 20 times before I start covering!

-MA

Sounds tasty. When ya do stripes - do you follow the rib orientation or use some width like 2" and repeat without concern for rib location?

Do the instructions include a scanable page with side, top and bottom profiles? I've been using Visio to play with possible schemes like the pic of a Somethin Extra below (this is just a construction view - not a covering view . Lets me throw different color combos plus I'm into self abuse using Bill Gates software ...

When I did my SSE, I put the stripes right on the ribs. I will likely do that here too - just makes it easier - IMO.

Yeah, it does - I will probably do some photoshop work when I get closer to covering.

-MA

I have Photoshop and CorelDraw too. Just don't know them as well as I do Visio. How about posting some of your trial schemes when ya get there?

Yesterday it was 73 and beautiful - today is blizzard conditions - go figure ...

When I get there, I'll be sure to post some pics.