SkyMaster MB339 Build Thread
#152
RE: SkyMaster MB339 Build Thread
Great pictures Christian.
I will use a Power Box Royal on mine and also the new AP-EV5UPRO multi valve.
How many air storage bottle did you installed ?
I will use a Power Box Royal on mine and also the new AP-EV5UPRO multi valve.
How many air storage bottle did you installed ?
#153
Junior Member
RE: SkyMaster MB339 Build Thread
Hi Gonzales,
I use the bottles coming with the kit.
One(the smaller one) for the brake and the two others for gear and geardoors.
This allows me to retract the gear five times.
Christian
I use the bottles coming with the kit.
One(the smaller one) for the brake and the two others for gear and geardoors.
This allows me to retract the gear five times.
Christian
#155
RE: SkyMaster MB339 Build Thread
F18
Took a while to write all and make pics.
Let me start start with saying that instaling both tubs and the front instrument panel was THE most frustrating part of the MB build. No info, badly fitting, all guesswork, You WILL need a lot of creativity to install them. I hated it so much that in fact I completed it only today, more or less triggered by Your request for info! (the rest of the plane is done...)
Here is how I did it, but anybody's solution is a good one.
First cut off both pilot's feet (horrendous job ) and put about 15mm of wood under their best parts in order to raise them on the seat. The pilots are too small for a good scale, so by putting them higher in the seat, it compensates. I glued them in place with silicon kit.
Then cut off the side flanges of the tubs, but don't make my mistake to cut off all, leave a rim of about 3-5 mms. I had to correct it back by glueing some thin plywood strips back in place of the flanges. The idea is to slip the pan flanges UNDER the cockpit side flanges.
The aft tub was too wide at the backside, I could not press it in the fuse, so I made a saw cut from top to bottom in the backside of the pan and glued both parts back to each other by a V-form. I put some tape on the joint to give some idea. The V should overlap about 1 cm topside to reduce width of the backside in order to fit properly.
The front seat rests on the front components plate, I just had to add a few mm's of balsa to have the pan sit tight in between the cockpit side flanges and the bottom.
The back seat pan I made simple "struts" on the aft components plate. You have to go the trial and error way in finding the right height. Here also the back pan fits snugly by resting its bottom on those struts and topside it slips under the cockpit side flanges.
Installing the front instrument dome is the real pain. If You let it rest in the small openings in the front cockpit pan, it will sit WAY too high, blacking almost all view from the front pilot.
In the end I completely cut off the front seat pan and redid that part with the help of 0.8mm plywood and lotsa superglue.
After repainting and re-installing some instrument plates, the end result is fine for me.
Now the front instrument panel can be set much lower, for reference look at the side view of the real MB339, I have included a pic.
To have that instrument panel sit tight I glued some balsa 10 X 10 mm, after some contouring, to the fuse side. Took one or two attempts. Once the bottom ones were OK, I put another set just above them, so in effect You will get a slit in which You can slide the instrument dome backward. Paint it matt black an You don't see them anymore.
The side flanges of the instrument panel needs to be trimmed back also for good fit.
Gonzalo, You can see how I installed my Weatronic. Get ALL the batteries and heavy stuff as far as up front as You can. I bought Lipos but I should have gone for good old NC cells. Way cheaper, simpler to charge, less dangerous, and the weight You need anyhow.
I use a triple air tank setup: Big main tank for gear/doors, smaller for wheelbrakes and another one for the airbrake. I am considering to modify it with one-way valves so I can fill all three tanks from one fill point.
I like the wiring attaching system Christian uses, saw them on JetPower but forgot to buy them, so I went the tie wrap route.
Radio setup:
All basic controls 65% expo
Ailerons differential (Down 50 % of Up travel)
Speedbrake pops out at 95% of flap travel, no elevator compensation yet, will do after testflights.
Wheel brake comes in at 60% DOWN elevator.
Gear sequencing done by transmitter delay, the rest Weatronic takes care of.
Lighting can be switched off-beacon lights ON-Beacon lights ON plus NAV lights ON. The nose gear light switches on when the gear is lowered AND the light switch is in any position except OFF.
Jetcat controlled by dual channel.
Took a while to write all and make pics.
Let me start start with saying that instaling both tubs and the front instrument panel was THE most frustrating part of the MB build. No info, badly fitting, all guesswork, You WILL need a lot of creativity to install them. I hated it so much that in fact I completed it only today, more or less triggered by Your request for info! (the rest of the plane is done...)
Here is how I did it, but anybody's solution is a good one.
First cut off both pilot's feet (horrendous job ) and put about 15mm of wood under their best parts in order to raise them on the seat. The pilots are too small for a good scale, so by putting them higher in the seat, it compensates. I glued them in place with silicon kit.
Then cut off the side flanges of the tubs, but don't make my mistake to cut off all, leave a rim of about 3-5 mms. I had to correct it back by glueing some thin plywood strips back in place of the flanges. The idea is to slip the pan flanges UNDER the cockpit side flanges.
The aft tub was too wide at the backside, I could not press it in the fuse, so I made a saw cut from top to bottom in the backside of the pan and glued both parts back to each other by a V-form. I put some tape on the joint to give some idea. The V should overlap about 1 cm topside to reduce width of the backside in order to fit properly.
The front seat rests on the front components plate, I just had to add a few mm's of balsa to have the pan sit tight in between the cockpit side flanges and the bottom.
The back seat pan I made simple "struts" on the aft components plate. You have to go the trial and error way in finding the right height. Here also the back pan fits snugly by resting its bottom on those struts and topside it slips under the cockpit side flanges.
Installing the front instrument dome is the real pain. If You let it rest in the small openings in the front cockpit pan, it will sit WAY too high, blacking almost all view from the front pilot.
In the end I completely cut off the front seat pan and redid that part with the help of 0.8mm plywood and lotsa superglue.
After repainting and re-installing some instrument plates, the end result is fine for me.
Now the front instrument panel can be set much lower, for reference look at the side view of the real MB339, I have included a pic.
To have that instrument panel sit tight I glued some balsa 10 X 10 mm, after some contouring, to the fuse side. Took one or two attempts. Once the bottom ones were OK, I put another set just above them, so in effect You will get a slit in which You can slide the instrument dome backward. Paint it matt black an You don't see them anymore.
The side flanges of the instrument panel needs to be trimmed back also for good fit.
Gonzalo, You can see how I installed my Weatronic. Get ALL the batteries and heavy stuff as far as up front as You can. I bought Lipos but I should have gone for good old NC cells. Way cheaper, simpler to charge, less dangerous, and the weight You need anyhow.
I use a triple air tank setup: Big main tank for gear/doors, smaller for wheelbrakes and another one for the airbrake. I am considering to modify it with one-way valves so I can fill all three tanks from one fill point.
I like the wiring attaching system Christian uses, saw them on JetPower but forgot to buy them, so I went the tie wrap route.
Radio setup:
All basic controls 65% expo
Ailerons differential (Down 50 % of Up travel)
Speedbrake pops out at 95% of flap travel, no elevator compensation yet, will do after testflights.
Wheel brake comes in at 60% DOWN elevator.
Gear sequencing done by transmitter delay, the rest Weatronic takes care of.
Lighting can be switched off-beacon lights ON-Beacon lights ON plus NAV lights ON. The nose gear light switches on when the gear is lowered AND the light switch is in any position except OFF.
Jetcat controlled by dual channel.
#156
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RE: SkyMaster MB339 Build Thread
So, am I reading this right, the tubs (front or rear) are not connected to the canopy in any way? I was thinking of having the front tub attached to the airframe and having the rear tub attached to the canopy. so with canopy off the rear tub would be out of the way....
#157
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RE: SkyMaster MB339 Build Thread
ORIGINAL: F-18DiamondBack102
So, am I reading this right, the tubs (front or rear) are not connected to the canopy in any way? I was thinking of having the front tub attached to the airframe and having the rear tub attached to the canopy. so with canopy off the rear tub would be out of the way....
So, am I reading this right, the tubs (front or rear) are not connected to the canopy in any way? I was thinking of having the front tub attached to the airframe and having the rear tub attached to the canopy. so with canopy off the rear tub would be out of the way....
#158
RE: SkyMaster MB339 Build Thread
Thanks guys for the info...... [sm=thumbs_up.gif]
Today they started with the assembly of mine and a lot of progress was done. The last pictures will help a lot since the person who is assembling my jet, was wondering how to install the different elements under the cockpit and the little space that is left. Hopefully the jet will be ready in no more than three (3) weeks.
Keep pictures coming. I will make sure to post mine as soon as they keep advancing.
Today they started with the assembly of mine and a lot of progress was done. The last pictures will help a lot since the person who is assembling my jet, was wondering how to install the different elements under the cockpit and the little space that is left. Hopefully the jet will be ready in no more than three (3) weeks.
Keep pictures coming. I will make sure to post mine as soon as they keep advancing.
#159
RE: SkyMaster MB339 Build Thread
I also dropped the forward equipmet tray down about 1" to allow more room for valves and servos on it, yet still allow the front cockpit tub to clear.....FWIW
Dave, I'll prob attach one or both of the tubs to the canopy on my new 339 when I get it.....beware that the cockpit and 2 BBI pilots weigh about 3 lbs......do a 5-6 G push to vertical from an inverted pass and there is about 18 lbs on the canopy frame and hatch latch......a little mod for extra strength will definately be required if u attach the cockpits to the canopy......
Ryan
Dave, I'll prob attach one or both of the tubs to the canopy on my new 339 when I get it.....beware that the cockpit and 2 BBI pilots weigh about 3 lbs......do a 5-6 G push to vertical from an inverted pass and there is about 18 lbs on the canopy frame and hatch latch......a little mod for extra strength will definately be required if u attach the cockpits to the canopy......
Ryan
#160
RE: SkyMaster MB339 Build Thread
A lot of work was done on my MB-339 today. Servos are installed and also the light system in the tail, wings and front landing gear. They are trying to determine now, the best location for batteries, powerbox and valve. I think the solution will be to lower that wooden tray in order to better accommodate all the components.
I want all my batteries installed as forward ad possible but at the same time, a place that would allow me to take them out with no problem (in order to charge them at home and not loose time at the club).
I want all my batteries installed as forward ad possible but at the same time, a place that would allow me to take them out with no problem (in order to charge them at home and not loose time at the club).
#161
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RE: SkyMaster MB339 Build Thread
Gonzalo, can you give some details on the lighting system you are using? I am interested in the nose gear light...
I made some progress on mine last night. Basic stuff, but it is progress. I had to fab up my own nose doors as the ones supplied with the kit were horrible. the pictures show the progress....
I made some progress on mine last night. Basic stuff, but it is progress. I had to fab up my own nose doors as the ones supplied with the kit were horrible. the pictures show the progress....
#162
RE: SkyMaster MB339 Build Thread
The lights are from Flugmodellbau. You can find them in http://www.dreamworksrc.com/catalog/index.php?cPath=51 Call Linda or Tod and ask about the kit for the MB-339
#163
RE: SkyMaster MB339 Build Thread
She flies!
After some doubt about the weather conditions today we decided to have a go.
My son would fly the maiden flights. He suffers less from maiden flight stress, and does not have to carry the burden of the rebuild and the costs!!! So away with that macho feeling: I BUILT IT SO I FLY (or crash) IT, just use Your brain, step over Your emotions and take the least risky path.
Before the flight we took a range check, all perfect. With and without lights, smokepump on or off. The Weatronic failsafe programming we tested also, (my normal FC28 transmitter/receiver failsafe programming doe not work on a Weatronic...) I have set it to controls neutral and engine idle. For whatever it is worth...
The first flight was almost perfect, some nose-up trim needed only. For the rest: rocksteady! View on the plane ist just terrific, compared to my cammo F16 and Hotspot. Thanks to the colour sceme and size we had never one second doubt about its bank angle.
The total flying impression is one of a large and heavy plane, which needs gentle coaching, not ham fisted control inputs. It sure eats up airspace, turn radius are not like a small trainer!
A good decision proved to be to leave the gear down, after the flight the airpressure was just about gone! Absolutely incredible, after so many on ground tests! Strange that the second flight the pressure dropped again, but only 3 bar, iso the whole 7 bar of the first flight. I have to dive into that problem. Maybe the cold was a factor, but I suspect the wing flexing that strains the fuse/wing quick disconnect couplings.
The Flugmodellbau light set proved to be impressive. Both the beacon light plus the ventral white "strobe"light were excellent visible in flight, especially the white strobe against a darker underside when turning away was immaculate! The nose light suffered from misprogramming and therefore was on and off. I have had this before that the light unit changes its program, probably after recharging the battery. Also attention needed here. Anyhow, the times it dis illuminate, the light intensity was something to be seen.
The second flight was even more uneventful, but also with gear down for safety. At lower speeds some rudder mixing with ailerons proved necessary to maintain coordinated flight, I will have the mixer activated by the gear switch.
The landing was textbook, full flare, albeit with the last seconds at full UP elevator.
We omitted the combined use of the flap and speedbrake, as inflight test showed a remarkaable nose up tendency in this config. So landings were at about 80% of flap travel.
The combined symptoms of a full elevator flare and the nose UP trim do make me think the CG is a bit too FWD, I might remove some lead from the nose. But first I will make a flight with a full (saddle) turned-smoke-tank, which sits behind the CG. In the event the smoke pump does not work, one has to land with that tank still full, but maintaining CG integrety
We just finished a bottle of wine in celebration!
Pics are not the best, combo of cold temps and tele!
After some doubt about the weather conditions today we decided to have a go.
My son would fly the maiden flights. He suffers less from maiden flight stress, and does not have to carry the burden of the rebuild and the costs!!! So away with that macho feeling: I BUILT IT SO I FLY (or crash) IT, just use Your brain, step over Your emotions and take the least risky path.
Before the flight we took a range check, all perfect. With and without lights, smokepump on or off. The Weatronic failsafe programming we tested also, (my normal FC28 transmitter/receiver failsafe programming doe not work on a Weatronic...) I have set it to controls neutral and engine idle. For whatever it is worth...
The first flight was almost perfect, some nose-up trim needed only. For the rest: rocksteady! View on the plane ist just terrific, compared to my cammo F16 and Hotspot. Thanks to the colour sceme and size we had never one second doubt about its bank angle.
The total flying impression is one of a large and heavy plane, which needs gentle coaching, not ham fisted control inputs. It sure eats up airspace, turn radius are not like a small trainer!
A good decision proved to be to leave the gear down, after the flight the airpressure was just about gone! Absolutely incredible, after so many on ground tests! Strange that the second flight the pressure dropped again, but only 3 bar, iso the whole 7 bar of the first flight. I have to dive into that problem. Maybe the cold was a factor, but I suspect the wing flexing that strains the fuse/wing quick disconnect couplings.
The Flugmodellbau light set proved to be impressive. Both the beacon light plus the ventral white "strobe"light were excellent visible in flight, especially the white strobe against a darker underside when turning away was immaculate! The nose light suffered from misprogramming and therefore was on and off. I have had this before that the light unit changes its program, probably after recharging the battery. Also attention needed here. Anyhow, the times it dis illuminate, the light intensity was something to be seen.
The second flight was even more uneventful, but also with gear down for safety. At lower speeds some rudder mixing with ailerons proved necessary to maintain coordinated flight, I will have the mixer activated by the gear switch.
The landing was textbook, full flare, albeit with the last seconds at full UP elevator.
We omitted the combined use of the flap and speedbrake, as inflight test showed a remarkaable nose up tendency in this config. So landings were at about 80% of flap travel.
The combined symptoms of a full elevator flare and the nose UP trim do make me think the CG is a bit too FWD, I might remove some lead from the nose. But first I will make a flight with a full (saddle) turned-smoke-tank, which sits behind the CG. In the event the smoke pump does not work, one has to land with that tank still full, but maintaining CG integrety
We just finished a bottle of wine in celebration!
Pics are not the best, combo of cold temps and tele!
#164
RE: SkyMaster MB339 Build Thread
Hye Richard (and Thomas),
congrats with the maiden of your MB339, she looks great on the photo`s.
Hope to see it flies in real life at a time.
Many succesfull flight.
Greetz,
Berto.
congrats with the maiden of your MB339, she looks great on the photo`s.
Hope to see it flies in real life at a time.
Many succesfull flight.
Greetz,
Berto.
#165
RE: SkyMaster MB339 Build Thread
Richard:
Congratulations on your maiden. The airplane looks great..... specially with the lights on.
They are still working on mine and Flavio (the builder....) has accomplished to do a lot of things in only five (5) days. All servos are installed, lights are ready, pipe and turbine installed, etc.
Congratulations on your maiden. The airplane looks great..... specially with the lights on.
They are still working on mine and Flavio (the builder....) has accomplished to do a lot of things in only five (5) days. All servos are installed, lights are ready, pipe and turbine installed, etc.
#166
Junior Member
RE: SkyMaster MB339 Build Thread
Hi Richard,
congratultion to your maiden.
Well done.
I think your MB is nearly perfect with all
the changes you have done.
Greetings
Christian
congratultion to your maiden.
Well done.
I think your MB is nearly perfect with all
the changes you have done.
Greetings
Christian
#167
RE: SkyMaster MB339 Build Thread
Christian, tks! But still along way to go to get all perfect.
I had some problems with the lighting system during the flights, it looked as they lost their programming, now I just checked it....all perfect. Beats me!
Gonzalo, what is that long black thing in the cockpit, a carbon stiffener in the side of the fuse? Mine does not have this! I guess the product will improve with feedback of customers!
If only SM made the tail LIGHTER!!!!!!
Your builder Flavio makes a nice wiring, is he a professional builder?
In 5 days......he must be also a wizard! Hopefully this thread gives some help!
I had some problems with the lighting system during the flights, it looked as they lost their programming, now I just checked it....all perfect. Beats me!
Gonzalo, what is that long black thing in the cockpit, a carbon stiffener in the side of the fuse? Mine does not have this! I guess the product will improve with feedback of customers!
If only SM made the tail LIGHTER!!!!!!
Your builder Flavio makes a nice wiring, is he a professional builder?
In 5 days......he must be also a wizard! Hopefully this thread gives some help!
#168
RE: SkyMaster MB339 Build Thread
Richard:
All the information you have posted have been of great help for my build. Flavio you could say is a professional builder but he doesn't have a lot of experience with Jets, so all the pictures and info of this psot has been of great help for him.
The long black strip that you see on the side of the cockpit, is carbon fibber. It was installed by Flavio just a precaution because that area of the jet is subject to a lot of force during high G maneuvers. I've never seen a MB_339 from Skymaster develop a problem in that area, but I have seen some videos of Fei Bao airplanes exploding in air due to a structural failure in that area.
Since the front of the airplane will need some extra weight anyway, using some reinforcement in that area doesn't create any problems. We are also replacing the servo trays for ones made of a better quality plywood (thicker also....) and that will help also to give more strength to the plane.
All the information you have posted have been of great help for my build. Flavio you could say is a professional builder but he doesn't have a lot of experience with Jets, so all the pictures and info of this psot has been of great help for him.
The long black strip that you see on the side of the cockpit, is carbon fibber. It was installed by Flavio just a precaution because that area of the jet is subject to a lot of force during high G maneuvers. I've never seen a MB_339 from Skymaster develop a problem in that area, but I have seen some videos of Fei Bao airplanes exploding in air due to a structural failure in that area.
Since the front of the airplane will need some extra weight anyway, using some reinforcement in that area doesn't create any problems. We are also replacing the servo trays for ones made of a better quality plywood (thicker also....) and that will help also to give more strength to the plane.
#169
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RE: SkyMaster MB339 Build Thread
OK, I want to say that hinging doors sucks! BAD! 5 hours to hing the main nose door, and I am still not 100%. Major suckage!!!! At some point I hope this actually gets easier.
SLOWLY moving forward....
SLOWLY moving forward....
#170
RE: SkyMaster MB339 Build Thread
F-18, I saw u are using air cylinders for the nose doors....did u decide against the direct mechanical linkage? For what reason? Doors can be a real PITA, but they do get easier the more u do.....I finally got my replacement 339.....should arrive in a week or two....
U still on the fence about Speedworld? I am definately going...
Ryan
U still on the fence about Speedworld? I am definately going...
Ryan
#171
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RE: SkyMaster MB339 Build Thread
ORIGINAL: furloughed ual
F-18, I saw u are using air cylinders for the nose doors....did u decide against the direct mechanical linkage? For what reason? Doors can be a real PITA, but they do get easier the more u do.....I finally got my replacement 339.....should arrive in a week or two....
U still on the fence about Speedworld? I am definately going...
Ryan
F-18, I saw u are using air cylinders for the nose doors....did u decide against the direct mechanical linkage? For what reason? Doors can be a real PITA, but they do get easier the more u do.....I finally got my replacement 339.....should arrive in a week or two....
U still on the fence about Speedworld? I am definately going...
Ryan
I am not 100% sure on Speed World, I might just jam down for one day as I have a mandatory Coaches meeting on that Saturday.....I will advise as we get closer....
#172
RE: SkyMaster MB339 Build Thread
F-18, I got the Blue and White Italian scheme....I really like to looks of a custom painted plane, but the more I look at the Frecce Tricolori scheme, the more I like it.....besides, I can (and prob will knowing me) paint it at a later date.....
#173
RE: SkyMaster MB339 Build Thread
Today they resumed the work on my plane. Smoke system is ready and Flavio is starting to think about the placement of the different elements that go in the front part of the plane. Hopefully tomorrow all the wires will look in order.
One thing I ask him to do, is some kind of tray that would allow me to take out all the batteries in an easy way in order for me to take them home for charging. There's nothing worst than loosing time at the field because your batteries are not charged.
I forgot to say that I bought the plane from www.jetsrc.com and the service has been "GREAT". Michel who is the owner, lend me some space in his house to assemble the jet and he is personally checking how things advance daily. Great guy to deal with so if you need something, you can contact him for help.
One thing I ask him to do, is some kind of tray that would allow me to take out all the batteries in an easy way in order for me to take them home for charging. There's nothing worst than loosing time at the field because your batteries are not charged.
I forgot to say that I bought the plane from www.jetsrc.com and the service has been "GREAT". Michel who is the owner, lend me some space in his house to assemble the jet and he is personally checking how things advance daily. Great guy to deal with so if you need something, you can contact him for help.
#174
RE: SkyMaster MB339 Build Thread
Thanks Gonzalo, I am glad to have your new jet in my build shop at home, I get to check it out every day... I think we might do the maiden VERy soon...[X(]
Michel
Michel
#175
RE: SkyMaster MB339 Build Thread
Flavio keeps building fast. The fuel tanks now are installed and also most part of the components of the turbine. He says the plane is going to be ready for flying on Saturday...... [X(]