knifeedgeyak

Now that I figured out how to post pics with a little help I thought I would put up my Northstar build progress. I am working on the canopy and it had by far been the hardest thing to build on this plane. Anyone else have the same thoughts or advise on ways to make it fit better?

woopie

My Feedback: (6)

One thing I did to my Northstar was to divide the hatch in half and glue the rear half in place. Then make new formers for the open halves and have only the forward section removable. Still plenty of room for equipment and a stronger forward fuselage.

knifeedgeyak

Do you have your servos mounted as per the plans? Do you perhaps have a picture of your bird?

Lamoilleriver

Would also like to chime in regards to the hatch, it certainly gave me some fits. Decided on my next Northstar to leave the side pieces in place and just use the top as a hatch, holding down with four screws, one in each corner. Would go a long way to making it alot easier to build and keep waterproof.

woopie

My Feedback: (6)

Here are a few shots of the hatch area.
The inside of the removable hatch is coated with thinned epoxy lay-up/coating resin to seal the wood.
The 1/16" ply tabs (w/screw holes) lock the hatch in the fuselage opening for side to side alignment. The nut tabs in the fuselage have 4-40 brass threaded inserts and use nylon screws. Where the hatch bottom frame edges meet the fuselage opening, a shelf, or ledge was created along the fuselage mating sides and back edges to support and leave a cavity for a thick bead of silicone sealant.
Before applying the silicone, all the inside areas of the fuselage hatch and nose cavity are sealed with coating epoxy. Silicone sealant is then applied to the created ledge and the angled face of the forward surface. The hatch is sprayed with a silicone mold release and pushed down in position. 4-40 steel screws are sprayed with mold release and screwed in place. Silicone sealant that has oozed out is wiped off with paper towels and a bit of alcohol. Let silicone cure for at least 48 hours! Before flying I run a thin bead of vaseline to
the silicone seal for further waterproofing.
Wish I had some construction photos for you, but this Northstar was built 21 years ago.

edited for added text.

knifeedgeyak

Well it sure looks nice. I am closer to getting it right but what a fight it has been.

woopie

My Feedback: (6)

Thank you.
Another thing I did was hollow out the nose block and cut an access hole in the front former. The lead shot I used for nose weight was all in the nose block and held together with epoxy coating resin. As I felt the supplied ABS engine cowl was a bit heavy, I used it to make a mold for a fiberglass copy. One thing about using coating/laminating epoxy with fiberglass is that MonoKote really sticks to it.
She an interesting build and great flyer ... worth all the time she needs. Your's is coming along very nice.

woopie

My Feedback: (6)

Here's a photo of my added water rudder. 0.030 aluminum held on with no. 2 screws. The bottom of the rudder was capped with 3mm lite ply. Use a bit of silicone sealant in the screw holes before installing screws.
I've found that a bigger rudder tab, or made from a thinner aluminum, will bend in use.

russram

HI all from New Zealand I have had 3 Northstars now unfortunately my luck runs out often but i love these ships and i have a mate that loves building and not flying so he builds them and i stuff them but that over a 15 year period. The wing wooble is inheriot was all Northstars that i have had and the fix is to extend the tip float with a turnup and the vortex that comes off that square ended float is reduced and so is the wooble. My last ship i did this to is and it stoped that wooble. not that the wooble is anything to worry about. I flew my first two on a K&B 40 and my last one on a SC40 and it performed well my weight was 6.25lbs with 1lb of lead in front i have just aquired a second hand Nothstar so will be back flying one very soon. I have never had uc on any of my n/stars as i love them off the water to much. Putting a servo down the back is increasing the balast needed up front you have atleast a 6to1 moment to think about I always use nylon sleeve with bowden cable and get good throttle responce but it does pay to cover the motor end cable entry so the glow oil doesn.t get in and bind up the travel speed. c.ya Russell R NZ

Falcon6667

Who makes that kit?
Falcon

woopie

My Feedback: (6)

BALSA USA

knifeedgeyak

Hey guys I just wanted to get some input on covering these birds. My first plan was to glass the hull and ultra coat the rest. I have now moved onto doing the hull with 6oz and the rest of the fuselage with real light 1/2oz then painting the fuselage. The wings and tail surfaces will be ultra coat. Oh ya the tip floats will get glass and ultra coat. Let me know if this is a sound covering plan or if there are better ways.

Thanks

woopie

My Feedback: (6)

I feel 6oz fiberglass is overkill and requires more finishing effort. Fiberglass on the tip floats is also overkill.
I used K&B Medium (2oz.) fiberglass for the pylon area and forward bottom of the hull step. On the rear of the hull step I used K&B 0.075oz.

If you plan to use a 0.46 engine and expect it to perform, your overall weight should be under 6.75 lbs.

knifeedgeyak

I am using the 6 oz mainly because that is what I have and it is what I do all of my floats out of. I use the West Marine 5/1 system. The finsh is great no matter what cloth you use. The Tip floats are going to be done with two layers of 2 oz. I am using a O.S. 46ax with a Macs tuned pipe for power and a apc 10x6 prop. I am just about done with construction and will start finishing next week.
Here is a picture of my last set of floats glassed with 6oz.

I wish I had a closer and better pic but I don't. This is the same stuff I use on my sail boats.

knifeedgeyak

Seems like this thread has kind of died, but here are some pics of my construction completed Northstar. I still have to do the nose but I am going to cover then use the nose to balance the plane as much as possible.

Falcon6667

Lookes great......next time take a pic. of you holding the plane so i can get a idea how big it is.
Falcon

knifeedgeyak

The wingspan is 44in and the length is 54 in. Not a huge plane but it is one piece so it is going to be a bit of a problem transporting it. I have been wanted to build a trailer for some time and now I just might have to.

knifeedgeyak

I guess this thread is dead. Anyways, I started to cover my northstar yesterday. Got the bottom, tip floats and the engine pod glassed. I am going to glass the rest of the fuselage with real light glass and paint it. That way I don't have worry about my covering coming off in the water. I will take some pics during the next session.

Deadeye

Yours is entirely sheeted then? And the thread isn't dead, it's just not building season right now in Montana!

MinnFlyer

My Feedback: (4)

Geeze, I've been so busy lately that I haven't gotten to the Seaplanes forum in a long time!

I built a Northstar years ago which eventually met its expiration date, but I picked up another at an auction last winter. It looks to be built stock.

I'm using an old OS 46FX and it's plenty of power.

I also have the wing-rocking problem (Which I had on my original one also)

As for covering: Start by covering each corner (Like where the wing meets the fuse, or where the nacelle meets the stab, etc) with a 3/8" wide strip of covering.

I showed this technique in my covering videos. If you haven't seen them yet, have a look:

http://www.rcuniverse.com/magazine/a...article_id=726

Lamoilleriver

Minn flyer - glad to see you are a Northstar owner again, curious as to your comments to "wing rocking" both planes had the same problem? do you know of any solutions? Appreciate any help. Thanks

MinnFlyer

My Feedback: (4)

If I knew a solution, I wouldn't have the problem

Someone mentioned winglets earlier (or in another thread, I forget) That might be interesting.

Deadeye

I am convinced it is lack of speed, after seeing my buddy Duane's exhibit the wing rock with the 65 four stroke. Once he put the 60 piped two stroker, no more wing rock, just rocket speed. I don't know what your altitude is, Minn, but we are about 3300 ASL here. .46 just wouldn't cut it up here, I don't think.

MinnFlyer

My Feedback: (4)

I'm at about 1300ft ASL and it's plenty fast. In fact it seems to do it the most at high speed, especially after a turn - but then it settles down.

Deadeye

Perhaps it could be CG then? I'm pretty sure Duane didn't remove weight to the nose when he put the lighter two stroke on. So he's got a slightly rearward CG of where he was originally. Just a thought.