sweetpea01

My Feedback: (10)

I'm not new to R/C or building them. I have been flying mostly GS for the last 6yrs. I have built a few GS from kits and done the typical ARF as well.

thanks to GJC I picked up a JL F-16. I always wanted to get into jets and here I am. I also picked up a JC Rabbit to power it with.

This build thread will be a learning experience for me as I have never set one up, but I've been reading online quite a bit about others setups on numerous jets.

Feel free to jump in with suggestion and help (as I'll need it).

Of course I'll be on the buddy box until I get the waiver and I'll have some seasoned pilots check out the jet prior to any engine starts etc. But the primary building will be me at night mostly.


So things I need help with already.


-Ventral Fin placement. The plans are lacking here. Where do they go exactly.

-The JC Rabbit came with a small Propane tank. Do I use it? Pros/Cons



I finally got my heater in the shop going so the next few days the build will be moving along. Here are some snapshots of what I have to work with.

sweetpea01

My Feedback: (10)

Also on more thing I noticed.

When I placed a saddle tank in the plane it seemed to press against the top of the planes fuse creating a bulge (forward part of the tank). There is a large lip on the tank where the 2 halves were glued together, I may try to sand this down slightly if I can determine this is the culprit first. Once the tank was in though it didn't budge. Do I just sho goo them in or velcro them in place? Does it need any padding (not that a jet should have vibration).

marineA4

My Feedback: (3)

sweatpea01,

Sweet bud! I just did a purchase thru one of the local members here on a JL F-16. It should be scheduled for delivary sometime after X-mas, but i'm not looking at getting started on it till January.

Nevertheless, I'm pretty excited on getting it done. Looking forward to your build!

I plan on using the same turbine you have on mine. Let us know how the fit is............

Upon receiving mine, i'll help you out in any way possible. Hopefully we can figure some things out.

Best Regards and Merry X-mas,

Orlando

sweetpea01

My Feedback: (10)

Thanks. Going through my list of things still needed to buy right now.

Feel free to include your build here as well if you like since we are doing the same plane/turbine combo

marineA4

My Feedback: (3)

Sure thing Sweatpea.........Looking forward to seeing how it goes.
I'll post some pics of the jet when it arrives. I've been told that its pretty much all put together and just a few odds and ends to complete.

I still need to purchase the turbine. So hopefully after X-mas i'll place the order.

Got your PM, thats suck on the instructions. Is there somewhere written in the kit about control throw and recommended C.G. locations. I'm assuming that much should atleast be given....

Orlando

sweetpea01

My Feedback: (10)

This is what I've found so far by some others that flew the plane. Not saying they are right or wrong.


CG 160mm for maiden....adjust from there. The plans called for a more aft CG (around 170 I believe)

Elev 40mm 25% expo
Ail 20mm 25% expo
Rud 13mm 30% expo

marineA4

My Feedback: (3)

Thanks for the info,

Orlando

sweetpea01

My Feedback: (10)

Mike D from GJC runs more expo on Elev and Ail. I'll probably have 3 settings on the maiden. 1 with low expo. 2 with higher expo and 3 with more throw and more expo

jetdriver

My Feedback: (1)

definately move the C/G forward. I had a hand full on the maiden of mine. Very tail heavy. Start nose heavy, increase elevator and sneak back on C/G slowly.

marineA4

My Feedback: (3)

I heard and saw on the thread posted here "JL F-16 maiden Flight" I beleive he had his C.G. at about 160mm. All the control throws where mentioned there as well and from what I read seemed to have worked very well.

Merry Christmas,

Orlando

sweetpea01

My Feedback: (10)

MarineA4 I read the same thread along with Lasse's, Falconwings, Dr Dooms and think the 160mm or slightly more forward is where I'll start.


Still looking for some info on where exactly to put the Ventral Fins. I guess today I'll be measuring up the plans and the plane trying to find a good spot unless someone speaks up soon.


I'm also going to do the gear doors/cylinders today.......wish me luck there!

Wayne22

My Feedback: (2)

On the older ones, there were two panel lines moulded in the aft belly where the ventrals go...cut the slots and glue the fins in... cg ranges from 4.25 to 6.25" from the wing root. (I don't have a metric converter handy...)

marineA4

My Feedback: (3)

Wayne22,

Thats about right from what i've read. 25.4mm is equal to an inch so 160mm is 6.29 inches. Good starting point! 4.25 inches would be~107.95mm.

Sweatpea,

I'd love to chat with falconwings on his set up. He lives up north in Dallas and i'm in Houston. Hopefully I can maiden my F-16 up there with the guys.........
Just wondering, is there a bracket that must be made for the ventral fins so it can be fixed on the inside and removable if need be. I guess from what i'm reading is that they are permanatly installed by method of adhesive. And are the plans that was provided with the kit scale to the kit or scaled down version. I would think there be some sort of marks as recessed panal lines as mentioned by Wayne22......

Good luck with the doors and cylinders. That is the part that gets me, they are tough to work in those confined areas.........Wish my bird was here so I can go along with your build.

Regards,

Orlando

sweetpea01

My Feedback: (10)

Been working on the doors. The fit is not that good. I had planned to repaint mine so I'm getting them as close as possible but they won't go flush on all 4 corners just laying there.

I managed to get the Front door and one main door done. There is no easy way to do this. I should have paid the $100 or so to have someone else do it!!!!


WayneNo panel lines on the bird.......so its a guessing game[>:]


MarineA4 PM me for some documents that will help with your build (a little at least), include your email

marineA4

My Feedback: (3)

Sent you PM Sweatpea

Orlando

Wayne22

My Feedback: (2)

Then I guess you will have to use the TLAR method...

Lasse Palm

Ventral Fin Placement!
I have look at the original F-16(full size), and then I used Eyes measurement..

Regards
Lasse Palm

sweetpea01

My Feedback: (10)

Thanks for the lack of help guys. No really its ok, I'm just tired.

It took all day to get just a few things done.

Gear doors and cylinders are installed. I sanded the doors and put some filler around them to try to make them more flush. The bottom of the jet is now a mess. It was a major days work to get the gear doors to open enough to let the gear retract and extend without hitting the doors. Then trying to fit the cylinder to actually get the door open that far and fully close was a whole nother chore. Right now the $100 to have this done at GJC seems well worth it!

I installed one elevator servo (JR8611). Let me tell you that was not easy either. Screws in hard to reach places etc. I'll post some pics tomorrow of how I redid the screws for the servo mount so that it would be easier to get out for service. I also had to slightly grind the Alum servo holder to fit the JR servo since its a hair too large. I then installed the cover over the servo area with countersunk screws.

I set the rails for the turbine up and test fit the turbine. It apears I'll have to cut a small notch in the rail to clear the nut on the the bottom of the turbine mount. No big deal.

I traced out a new electronic board, but didn't cut it out yet.

I looked at where the planes call for the Ventral fins and made a mark in pencil. It doesn't appear to match my drawings for the mount on the inside to make them removable. I think I'll make the mount first and temp install it and try to cut marker holes from the inside first.

I drilled the holes to get to the bolts on the wing so you can tighten that up.

I played around with the Rail for the wing and put one of the missiles together to see what it looked like.


Questions of the day.........will the 9411 servo fit in the stock rudder mount?

What size servo do I need for steering, nothing I have fits in the mount on the nose gear?

Pics will have to wait for tomorrow as I'm tired.

marineA4

My Feedback: (3)

Sweatpea,

Thanks for the files you sent. Really helpful!

Not sure if the slots shown in the Landing Gear instruction manual 2nd picture from the top on the right side is for the ventral fin slots.........
I came up with an idea for your ventral fin location. I noticed that in the L/G installation photos there is a picture that shows slots cut out. (Right second picture from the top)
Take a measurement for reference somewhere on your plane, you need to take a reference measurement in the same general area as the picture shown.
Then go ahead and shoot a line from that reference point to your location on the airplane your working with.

Kind of hard to explain but its doable. I'd take a measurement of the center section piece forward and aft where the cutout for the mains are on your F-16. Then i'd go and reference the picture(might have to convert a measurement with simple math to your picture) to that same reference used earlier. Then after you've converted it, take and measure the distance from whatever refernce you chose to use to where the slots are located.

Hope this helps,

I'll try and post a pic of what i'm talking about.

Regards,

Orlando

marineA4

My Feedback: (3)

Sweatpea,

Hope the pics helps out

The red area shows the measurement you can do on your original airframe (the one your working on). You'll have to convert that measurement to fit your picture. Basically scaling the picture!
Then once you've found that, find your area shown in green (the slots aft of the main gear).

If you have any problems, shoot me a call.

Regards,

Orlando

sweetpea01

My Feedback: (10)

NO ONE SAID THERE WOULD BE MATH INVOLVED IN THIS BUILD!


Thanks that picture helps.

marineA4

My Feedback: (3)

LoL! I know what you mean. From what i've seen, a kit is not a kit anymore without having to put a little math into them.
Technically, when we adjust the C.G. on any airplane, we playing with some math..........and so on with other minor things we tinker with these toys.

Hopefully it will give you a close location to the install of the V fins.

Orlando

sweetpea01

My Feedback: (10)

No building yesterday or today........these are the days to spend with the kids

sweetpea01

My Feedback: (10)

Here's some photos.


First set are of the stock Elevator attachments. I didn't like where the bolts were. It made it impossible to get them tight. I moved them around to the other side. Yes the pipe will be in the way but that is easily removed if need be.

sweetpea01

My Feedback: (10)

Next I worked on the landing gear and doors. I really hated this part. Its about 85% done. Still some sanding and filling to do.