marc s

Here are the first few shots of the Mig15, as a project this is my first jet build so go easy on me, it may take a little longer than the pros, but it will happen, and I am hopeful that it will reward its owner (not me unfortunately []).

I build mainly in the evening so progress will depend on this a little.

The commission was intended originally to be a ducted (schubeler 96) conversion of this jet, but following discussions with Schubeler and others it transpired the ducting would not be up to the job of delivering the volume of air needed, so its going the turbine route, which one is yet to be confirmed.

Any advise, suggestions on this build as things move along are very welcome, so please chip in.

So far the LHS wing is at the stage where sheeting is the next task, I am awaiting the retracts to make sure the mounting plates have the correct hole spacings so the captive nuts can be applied, this I need to do prior to sheeting. I also need to add some additional aeropoxy to some addendum parts required to strengthen the wing around the critical auxillary spar and main spar joint area. Once this is done I will put the wing to one side and build the RHS wing checking all the same parts are used! When both wings are built up I will skin them.

As I wait for accessories I have put together the front ducting, using carbon tow as suggested for strength.

Today just start cutting out the hatches and airbrake paddles.

Ehab

My Feedback: (44)

there are some mods on the BVM website for the Mig 15. Make sure you do it all. Also, for the built up wing, there are important extra ply sheeting in the LG area to increase strength there. You are going to have fun with the stabs, they just need patience!!! I also saw a BVM Mig 15 with two servos for the elevators, you may want to look into doing the same. Gordon built the wings for me and I never finished it, too many ARFs in the market

I would recommend a P70 or a Wren.

What happen to the spell feature?????????

swansons

My Feedback: (3)

Marc,
You might like to go to the MIG-15 build thread already on RCU. It is on the newer AFS MIG but still has some interesting information.

http://www.rcuniverse.com/forum/m_40...tm.htm#4020351

John S.

wd40

My Feedback: (81)

Looks great you are going to have alot of fun with Mig. I am looking for Mig parts or old kits if you have some let me know.

marc s

Ehab, writing the thread at midnight (our time!) had something to do with the spelling, and I guess its the American spell check which is not the same as ours!

Cheers for the early feedback, looks like two key things here to fix, wing strength in the landing gear area, and air plumbing to doors and retracts.

In the build you can just see in the wing shot additional ply panels forward of the flap tray, these two effectively fill the gap between the ply servo tray, the auxillary spar and the main spar, so far I have also added thin cf sheet infront of the main spars to form a double layer of webbing. I also plan to cf line the wheel bay area - if there is any extra mods possible please let me know.

With regards to air systems, is the best solution to go for 4 or 5 connectors per wing, as I prefere to get this sorted before closing things up, the fuselage plumbing can wait (so to speak).

I will send over a mail to BVM to see if they have any additional feedback.

Marc.

rhklenke

My Feedback: (24)

Marc,

The plans for the Mig show 3 EZAir connections on each wing - two for gear, and one for brakes. The connections for the door cylinder are shown using airline quick disconnects. I'm going to use 5 EZAir connections on mine and I know others have done it that way too...

Bob

Ehab

My Feedback: (44)

Here are some shots of the built up wings. can you see the ply in the LG area?

marc s

A little more done over the weekend, I have to say however the instruction manual is well documented but the descriptions are a little vague sometimes and you really have to treble check all jobs to make sure nothing should have been fitted earlier!

Managed to cut out the speed brakes, which due to the shape require alot of patience. Once cut the best way (after a few failed attempts!) is the tape them back in position on the fuselage and then fit the support frames whilst they are in position. any tension in any direction distorts the brake and they do not line up.

Having glued the brake structures the hinges were the next job, following a few trial and error attempts I decided to measure the distance from the hinge base to the pivot pads, this then was translated into some ply blocks which were stuck to the former allowing it to be fitted to the fuselage in exactly the correct position so the hinges would line up. You will also see some "T" lengths of balsa which kept the former located and parallel until some spot zap-gap held things tight.

In the end only minor tweeking on the fitting was required - more pics tomorrow.

Marc.

wd40

My Feedback: (81)

All repairs almost done on my BVM Mig 15. I hope to have her ready for FL. jets This is a great flying jet, I have removed the p70 and will install something with more power at 24 pounds. The P70 just didn"t get it done.

enny wang

�常�常美丽!!

marc s

OK, the wifes made off with the camera, on an overnight 'team building' session so no pics today. Only had a few hours since the weekend but got the two airbrakes in and hinged, also used the revised hinge system for the front doors and have those in as well.

Whilst I wait for some key hardware I wanted to ask a question:

The plans show the wing construction complete with aileron, and the process involves sheeting the wing to the edge of the aileron, then sheeting the aileron still in situ. Once this is done you 'cut' the aileron from the main wing.

Concern 1: You need to be very accurate in the cutting off of the aileron, not only do you have to cut through ribs but also at the right angle so the resulting cut on the opposite surface in spot on. As an operation this seems very hit and miss, with more chance of the miss!

Concern 2: If the aileron does come off clean, you then have to remove the .2 of an inch stubs left on the original ribs, to get back to the aileron spar which is set back from the wing sheeting edge by this amount, I just know some damage to the sheeting edge is going to happen however careful you do this.

So, why not remove the aileron rib sections before sheeting, spot gluing some rib standoffs infront of the aileron spar so that the wing is still held in the correct position, as the aileron ribs sections carry the current standoffs. Using the plans build the aileron, nice and flat, and sheet the wing leaving a .2 overhang on the aileron spar.

As I plan on modifying the trailing edge of the aileron to strengthen it against wharp, as I have done so on the flap trailing edge this process would help me no end.

Have I missed something here?

Comments, advise please.

Marc.

Gordon Mc

My Feedback: (11)

Hi Marc,

What I did for building this, was to leave a very small (about 1/32") gap between the sheeting of the wing and the sheeting of the aileron. Thos clearly sohws you where to cut the parts.

After the aileron is cut out a cap strip gets glued on the front. This means that you can sand the fornt of the rib + sheeting assy before gluing the cap strip on - so if you end up sanding more than you want on the front of the aileron, just increase the width of the cap strip slightly if needed.

marc s

The latest and some pictures from the earlier entry.

Front gear door was hinged using the 'alternative' BVM addendum, which differs from the original in that flat pin hinges are used as oppose to hinge arms like the ones used on the air brakes. The reason for this is that the original system permitted the gear doors to open onto the gun locations, which can cause a leverage resulting in a hinge failure. The modified system prevents this over opening, and looks to provide a stronger hinge assembly (IMO!)

Now that my supply of syringes is back to capacity the aeropoxy is being added to the areas requiring it!

Cleaned up the forward hatch area, and trimmed the cover to fit, set the fixing in place which I have to say is simple and looks very effective, essentially two lengths of piano wire passing through snakes which are aeropoxied into position - slide the wire in and the whole lot locks up in each of the 4 corners.

Hopefully the hardware will be with me next week so will be able to move the wings on, and start on the front landing gear installation.

In the meantime I spotted in a book on the Mig15, landing lights, what interested me more was that the front one is mounted in the top 1/3 of the air intake duct, which looks really neat, and I am going to have a stab at tackling this addition, along with the two landing lights positioned just forward of the wing landing gear inner door (one in each wing), I have contacted a UK source for model plane lights, but would welcome any contact details or suggestions from you guys as to how to achieve this.

Currently I am considering a small 14mm diameter reflector, complete with a high intensity 5mm LED which I am told will be very bright (14,000mcd) for the front landing light a 12mm reflector and 3mm LEDs. Navigation lights will be as per full scale on wing tips and trailing end of fin fairing.

A link to the site I have looked at is [link]http://www.lightingforaeromodellers.co.uk[/link]

Pics below.

Marc.

marc s

Before the wings are sheeted I decided to tackle some landing lights. On the Mig there is a neat one fitted to the top of the inlet duct, and two further lights, one each side near the inner wing landing gear door.

After a quick search on the internet I tracked down a UK supplier of light systems for model airplanes, using some very high intensity LEDs, and some natty little reflectors an order was placed for three landing lights, 14mm reflectors, a red (port) and a green (starboard) wing tip set, and a white rear tail light.

The landing lights will be timed to come on with the gear down, probably via a microswitch connected to a door, the most likely being the front wheel gear doors. The navigation lights will be on permanently during flights, but will have a switch to disable should it be required.

Wired the left hand side wing tonight to check the effect, running the whole system from a 2s lipo (1320mAh) will give over 2 hours of continuous lighting, each LED draws around 100mAh.

Next job will be to fabricate a clear cover to go over the front landing light, which will require a mould being taken of the duct, so a plug can be made to vacuum bag a piece of clear plastic to fit the complex shape.

Marc.

marc s

Involved - what a job these built up wings are, loads of tweeking, sanding, waiting for glue to dry - but slowly moving on.

Decided to deviate from the build manual and split the aileron from the main wing before sheeting, I cut the aileron ribs from the wing structure making standoffs beforehand to keep the whole wing straight. Using the same system as the flap trailing edge, fabricated the ply top skin and trailing edge with carbon to help keep everything straight - bottom surface is balsa sheeting.

Leading edge fitted and sanded to shape, notches cut for robarts.

Flap constructed in the normal way but with the addition of a cf strip running the full length to add stiffness and replaces the three stringers.

Hope to have the landing gear this week so will be able to fit mounts and skin the wing! The second wing should be much quicker now that all the hard works done fathoming out all the assembly techniques and mods.

Not the most exciting pictures to show for 6 hours work.......

marc s

Still waiting on the harware, so have tackled a few bits and pieces.

Still strengthening the wing landing gear area after reading some more build threads, but cannot do the final work until the gear is here, will add cf thin plate to spar webbing as the balsa seems to crack on heavy landings which results in the wing twisting resulting in the top skin splitting. Once the landing gear is in and checked I will also apply cf to the inside of the wing skin in the landing gear areas.

With the decision to add some lighting (nav & landing) to the model I needed to fabricate a clear cover for the front inlet duct landing light. A mould made from two layers of cf cloth and some 5 minute epoxy, after some work finishing, the surface was ready to cast the plug. The mould was pva release coated, and waxed with a couple of coats of ordinary furniture wax. A mix of 15 minute epoxy was poured in and the resulting mixture created a working plug.

With a little stopper sanded back my local model shop will vac bag some medium weight clear sheeted casts from this tomorrow.

I have also added some extra cf to the front landing gear areas, as this area is always subjected to large stresses and strains.

Until later...

John Redman

My Feedback: (8)

Hey Marc,

Landing lights look awesome, but what version of the 15 are you building? In all the versions I have seen and worked on over the last 20 years, they all have only one landing light. Most common location is in hte intake splitter. The later versions of the Mig 15bis it was relocated to the left lower wing in front of the main gear door. I have never seen one in any of my books or real planes with it having more than one landing light on the plane, in weither of the two locations.

I am a Mig lover and continue to build my documentation for the bird so I am always looking for new info. Plus just trying to help a fellow Mig brother out if I can. You need to make sure you build in the mechanical flap and gear indicators on the wing and fuselage, not to mention the gear down lights on the struts for visual reference from the ground.

Here is a picture of my Mig back in 2002 (still have it), with droppable wing tanks, sliding canopy, operational mechanical indicators, and over 140 pieces of plastistut in the speed brakes. My version had the landing light in the lower left wing skin in fron of the gear door.

Your build looks awesome. You are going to love the plane in the air, there just isn't anything that flies as well as the Mig does.

maramotts

My Feedback: (8)

I have also just recently picked up a mig (older version) and had a couple of questions regarding the upper rudder and counter balance weights on the stabs.
Has anyone made the upper rudder functional with success at the same time hiden the rudder linkage? as far as the counter weights the plans indicate an optional scale part but after talking to bv i was notified that they are no longer available, what is the best way to replicate the counter weights?
Mr. Redman i would love a picture of how you made the flap and gear indicators.
P.S. Marc great thread keep it coming

marc s

Thats an interesting question, I guess for the scale build it would look great, however the weight penalty in this sensitive area would need to be very carefully considered. I would be interested to see any options however.

John, yes if you have any info on the markers then that too would be of interest, especially as I have got the materials to fabricate these items (with a few of my own thoughts for installation!)

I will be revising the lights following Johns advise (thank you), and will post details when the gear arrives.

Marc.

John Redman

My Feedback: (8)

My upper rudder is operational and has a hidden linkage. Pull-pull with an 8411 using welding rod (3/16" diameter) for the torque rod into the bottom of the rudder. Works very well. I used 3/16" diameter welding rod (brass bushed) for the torque rod between the upper and lower rudder as well.

If you conceal the elevator linkages this is done with 5/32" welding rod I believe. Dave Ribbe has them on his. I did not conceal my elevator linkages.

marc s

John, can you explain the set up again, as I did not grasp the gist of the linkage adaptation. Would you also explain how the wing markers are linked in your model to the flap position.

Any info on the elevator conversion would also be good.

Fitted the splitter landing light this afternoon, and together with the vac formed clear plastic cover it looks the part - certainly bright enough to be highly visible during the day light.

Later...

maramotts

My Feedback: (8)

Mr. Redman Thanks for the info any pics please? Marc here is a pic of the head lamp and strut lights which i belive were added later maybe someone can verify that, you can also see the flap and gear indicators which would be a great scale addition

marc s

Cheers for the pictures, the light in the splitter i have photos of but the gear leg lights are good to see and the indicator markers. The light in my ducting is now fitted and the reflector will be added to make the overall look more in scale with the actual light.

Have a great weekend all.

dribbe

Let's see if we can see the light in the picture? Is it big enough?

Basically, to do it well, you need to make a pattern, and vacuum form a clear plastic cover for the 'outer lense'.
I used a mini maglight bulb and reflector... and a radio shack 2xAAA battery box.

Have Fun,
David

maramotts

My Feedback: (8)

Mr.Ribbe can you tell us whats the best way to make the upper rudder functional and hide the rudder linkage, maybe a scetch or pic?