IL2windhawk

Hey guys,

I'm planning to do inner gear doors with the electronic sequencer too.
Something kind of interesting crossed my mind today, and I wanted to
get some opinions on it. I haven't heard anyone mention this idea yet,
but maybe it has tried it before.

Previously, I was planning to use the first sequencer output to control
the servo that would activate the retract valve (and thus the landing gear),
and then use the second output to run a servo that would activate linkages
for the inner gear doors.

Well, I saw some of those isolated pnuematic cylinders that aren't installed
in a retract or anything,

(these: http://www2.towerhobbies.com/cgi-bin...?&I=LXET28&P=7)

and I thought maybe I could just connect one end of the cylinder to the inside
of the inner gear door, and the other end to the inside of the wheel well. That
way, as the cylinder piston extended, it would act as both the linkage and the
actuator! They would also provide very rigid and precise end points.

Well anyway, it crossed my mind that I might be able to use the same air
tank to actuate both the pnuematic landing gear and the above-mentioned
pnuematic inner gear doors.



Basically, you just T-off from the main line, and add a second valve. You could
get two different outputs from a single air tank. At least I think so.

Here's kinda how it would work in my airplane:
You flip the landing gear switch, the gear sequencer responds by activating
servo #1, which on my plane would open the inner gear doors (there would
actaully be a cylinder for each door), then after a few seconds the sequencer
activates servo #2, which would lower the landing gear (once again, there
are two pistons, these ones built into the retracts), then after a few seconds,
the sequencer closes the gear doors by returning servo #1 to its initial state.


I figure that you could even T-off another line to activate something else, such
as an opening/closing canopy that would function completely independently on
another channel altogether.

It seems to me that as long as only one valve is working at a time, there would
be no problems. What do you guys think?

Sorry - long winded.

N1EDM

My Feedback: (2)

jeffk464,
Can you give a link to CMP?

Thanks,

Bob

zope_pope

IL2Windhawk,

That is a really cool idea. The only bad thing is you'd lower the amount of cycles between fills. Thanks for pointing this out. As I am still in planning of what to do with my wing before sheeting it, I am sure this is lighter than putting an extra servo in. Any ideas on how to mount the cylinder and still keep it clean looking? This will be my first retract setup, so I am still very new to all this.

I am also planning to put nav lights as well as landing lights which fold out when the gears are lowered. I have seen those Ram brand lights at tower hobbies, but am not sure they are the right size. Should add some really cool scale effects and head turns if done right. If anyone has input on this, let me know. I bought the Aero-pac CD for the Big Beautiful Doll p-51, and it is helping tons in my planning. Here is a link to the site: http://www.airbornemedia.com/store/aeropac.htm . I'd highly recommend it for riveting, close ups of everything, and quite a few 3 view drawings.

IL2windhawk

Hey Zope,

unfortunately, one would still need a servo to actuate the extra valve.
I'd bet weight savings are minimal with this system. Still cool though, huh
The issue of losing pressure is a concern, since the inner doors would
move twice per gear deployment!

I'm so far from that stage that I can't really say exactly where I would
exactly mount the cylinders.

Thanks for the link

ticketec

My Feedback: (2)

Hey IL2windhawk,

You are almost on the mark with your retract ideas.

Firstly, there are two main ways of actuating retracts and inner doors the first is servo driven, and the second is air driven. What i am doing is a combination of the both.

Most of the larger warbirds use pnumatics only to do the gear, inners, and tail retract. You don't need to use the electronic sequencer. There are many manufacture's of pnumatic sequencing valve that will, with the movement of one servo, sequence the inners and then the gear all for you. check out this site

http://www.up-1.com/valves.html (you would need to use something like the UP-2)

The ultra presicion mob are meant to be the bee's knee's. This eliminates the complication and switch sequencing that you would have to do to get it all working right. not to mention the cost and weight of the two servos and the electronic sequencer.


I think punematic all the way is the best thing, I'm just doing it cheaper by using the servo for the inners..

Thanks

IL2windhawk

Thanks for the link and info, Ticketec.
Very interesting.

Are micro servos strong enough to operate the robart valves?
That could be one way to save cost and weight?

jeffk464

No problem Ed
http://www.raidentech.com/cmpuspairfom.html

That is not a link to CMP but to a distributor.

jeffk464

Here is a picture of the kit.

Cpig

Zope, great thread here, glad you started it but now you have to stop slacking off and finish your damned plane! I'll even drive down to Littleton to see it fly. (I'm in the Army here in Colorado Springs).

I spent hours last night reading through this thread like a suspence novel. Only problem is when I got to the end here, there was no end! What's up? You guys need to get off your butts and finish these things so we can see and hear about how they turned out. I was downright dissappointed in you guys - Zope, Intermidiot, Asphalt, etc...
People like me are counting on you guys to finish these things and keep us posted. And Asphalt, come on!!! are you trying to tell us there hasn't been a nice flying day since you finished that thing ?months ago? If you're scared just say you're scared. (I'm half joking here, of course) I know the anxiety of flying for the first time that work of art that you pumped so much into. But just do it!

I built the same kit about 10 years ago and loved it. Too bad it burned in after about 30 flights. I finally got around to reordering another one so I will start on it tomorrow.

Here are a few things I'm changing on this one:

1. Don't use Century Jet Retracts. These things were a big let down = junk. I couldn't believe the outrageous price they charge for these things. They bent on almost every landing (I'll admit some of my landings weren't the prettiest but still). The shock absorber action was not all that smooth and they weren't machined with very much quality at all. (I used to be a machinist so I could easily see the poor workmanship put into these things.) Looked like they were made in China - and probably were.

I ended up ripping out the CJ retracts and putting in Spring-Air retracts. Much better quality, less than half the price and as a safety feature they spring down locking in the down position if your air system fails. I don't know why more people don't go with these.

2. Reinforce the main gear - think this has been said quite a few times throughout this thread.

3. Don't use a .60 size engine. This thing needs power, I ended up replacing the underpowered .60 with a 1.20 four stroke. Excellent power plant!

4. I'm pretty sure I will be fiberglassing this one. The monokote covering came out great on the last one but I want to give this one more details such as panel lines and rivets; the sharpie on monokote technique just doesn't do it for me.

5. Get a decent looking pilot. I don't understand why people build these beautiful planes then throw these ugly $5 pilots in them. Just go without a pilot if you can't put a decent one in there, that's what I did on my last one after searching in vain for a decent looking pilot.
Get the Aces of Iron pilot and follow the websites painting instructions. Awesome Scalemasters looking pilot for $20. www.acesofiron.com

6. Go with a retractable tail gear this time. Thanks for the tips on installing these (can't remember all of the names that posted on this but your work is appreciated; ticket, asphalte, and others).

7. I'd love to go with the Keleo muffler but I think I'm out of money. Maybe an upgrade if I make it past the maiden flight.

8. The last thing that I'm going to do different is not to fly it the day before a hurricane comes through.

ticketec

My Feedback: (2)

Hey Il2windhawk,

I'm using a Hs-81mg micro in mine and it's working fine so far.

Have the inner gears installed and the mains back in the wing and am working through the install. A few tips to look out for:

You have to mechanically set-up the inner door servo and retract valve servo because the Jomar sequencer doesn't let you use the radio funtions to do this. It's a pain.

I have upgraded the door servo from a Hs-81mg to a Hs-425 full sized servo because i though that is was going to struggle with the doors, but it wasn't. It was the robarts giving me grief.

The robarts are a pretty poor quality retract. they have over 1/4 slop at the wheel from brand new, with not adjustments to take it up either.

Pic's soon,

thanks

IL2windhawk

I don't understand this statement.

I test ran my sequencer, here's how it worked:
Plug two servos into the sequencer, which is connected to the reciever
Then just set the mode on the sequencer, and it operates the servos
accordingly.

What am I missing?
Thanks.

ticketec

My Feedback: (2)

The linkage lengths (servo to retract valve and servo to inner gear doors) and the throws have to be perfectly set-up. you cannot use the radios automatic travel adjustment, trims, sub-trims etc. to compensate.

The way i normally set a servo up is to get a little more throw than required and then reduce the tavel via the radio. then add duel rate, expo etc whatever is applicable to the control i'm setting up. for flaps, my radio can also adjust the servo speed, so i would slow the flap deployment too.

With the mixer, you have to set up the servos "old school"e.g. mechanically, and ensure there is no binding.

thanks

ticketec

My Feedback: (2)

O.k,

when down stairs and took a few pics of the inner gear doors.

They have been filled and primed, and are now fitted to the model. I also made a little right angled bracket to mount the ball-joint to actuate the door.

I have almost finished the wing fillets as well. I used really soft balsa triangle to make the "base" of the fillet and then rough sanded it to shape. I mixed resin with microballons up slathered it on top of the balsa. the only problem was that there wasn't enough microballons in the mix which meant that i was sanding almost straight resin. Arrrr, it was hard work. it took almost 4-5h of sanding with 80grit to get them to the state they are in now.

Thanks

tlgibson97

Call it a maiden flight or not. I took the mustang out to the flying field along with my older plane. I was there to fly my old one and see if anyone would be there to check over the mustang. I didnt have any intention to fly it. Mainly because I hadnt set up the throws and high and low rates yet. But since I was there, i went ahead and put her together and gasses it up to taxi it around a little. The grass is a lot smoother at the field then it is at home. So I took it out beside the end of the runway in the grass, lined it up and give it full throttle. about 50' down the runway it hit a small bump and became airborne. I immediately cut throttle and settled it back on the ground. At my field the ground drops off at each end of the runway so I had to get it slowed quickly. It nosed over easily when I turned at the end of the runway and stopped the engine, but no damage to anything so thats good. I got it in the air the wsame way one other time yesterday before I pushed it too far. So I say that it officially survived its maiden flight, even if it did only last 30ft. The wright bros didnt fly very far their first time either. It was nice to see that while it was in the air it didnt have and bad characteristics and flew nice and straight so it was a good little test even though I didnt get to take it any higher.

zope_pope

Nice looking wing fillets. I am so not looking forward to them.

Does anyone have experience with rigging up nav lights and landing lights? I can't find a good link or place to buy some from. I want to sheet the wing, but I want to wire the wing to make life easier later. Thanks!

IL2windhawk

check out this link, zope:
http://www.rcuniverse.com/forum/sear...D&sortMethod=d

Thanks Ticketec, for explaining your point about the end points.
Now I understand what you meant. I'm looking at mechanical
solutions to the problem, probably using a small semi-stiff spring
to let one of the end-points stretch.

zope_pope

Alright, I have decided on a lighting system. I can always switch out the bulbs if they are too big (my biggest concern while shopping), but all the features this system provides at this low of a price is amazing. Check em out, I'll take some pictures when they come in and hopefully come up with a good scale way for install.

http://www.starwoodmodels.com/products/cur/systems.php

My next project is doing the neccessary mods to the wing to accomadate scale linkages. And the money starts to disappear. hehe.

Cpig

Zope,
Which field do you fly out of? (RC that is). Let us know when you are finish that thing, I'm in Colorado Springs and I'd like to come down and check it out.
Joe

zope_pope

I fly out of cherry creek for now, but would like to join Mile Hi RC again. Both have nice guys, but I feel safer at Mile Hi RC as the rules are actually enforced. At cherry creek everyone flies everywhere. Taxis out of the pit area, etc. I just am always keeping an eye out for the airplane about to hit me. I hope to get my lights and other supplies i ordered by the end of the week, so hopefully I will do some wing work this weekend and get this project rolling again.

saramos

Hi guys,
I've been following this thread for about a month. There's some really great work going on here.

I just finished my TF Spitfire project (should maiden this weekend) and am getting ready for my next project, a TF P-51B.
I am wanting to do Snoots' Sniper, a B with the Malcom hood.

One of the early issues I am having is locating a good set of 3 views which shows panel lines and rivet detail. I've located some for the D, but not the B. Any help in this area would be greatly appreciated. Also, if anyone could suggest a good set of walkarounds for the B with a Malcom hood , that would be a HUGE help.

So far, my library of books and materials are , two sets of drawings from Bobs Airdocs, 352nd Fighter Airgroup, P-51 Mustang in detail & scale, Scale Aircraft Drawings Vol II, P-51 Mustang in Action. The P-51 Mustang, North American P-51 Mustang(Aero series), North American P-51 Mustang(Osprey), The North American P-51B & C Mustang, P-51 Mustant From 1940 to 1980, The Great Book of World War II Aircraft, and a number of other general WWII aircraft books. Unfornunately, none of these have the detail I am looking for.

Has any of you taken the step of aquiring a set of factory drawings, either on their own, or from one of the disks being sold on ebay?

Look forward to seeing your progress and looking forward to starting my kit,

Scott

Mustang1964

Teckitet:
Where did you get the inner landing gear doors for your bird? Does any body have a close up shot on how they attached the outer landing gear doors? I am about to join the wings and this is the next hurdle that I am going to try to jump.
Thank you guys. You all have been an inspiration and guidance so far.
Mustang1964

zope_pope

while we are on the subject of gear doors. How is everyone doing the tailwheel doors?

IL2windhawk

Heya Pope,

Check out these excellent Mustang 3-view drawings (for any variants):
http://www.war-clouds.com/forums/viewtopic.php?t=1094

I originally picked them up from somewhere on these forums.




I love the looks of those Malcolm-canopy Mustangs. Good Choice

saramos

I came across the files at airwar.ru some time ago. The zip with 18 tiffs do have the level of detail I am looking for, however, when comparing them with other 3 views, the outline and location of many of the panel lines are way out from the others. I do find some (mostly) minor differences between almost all the 3 views I've scanned and compared, but these, by far, had the greatest discrepancies.

Scott

zope_pope

Hey guys,

Thought I would post these links here as they show the installation of the RDS scale linkage system thing. Good stuff. I am placing my order tomorrow so I can get this build moving again. Man i have been saying that for a while, sorry for the delays guys. I just want to make things easy for me later.

http://www.rcuniverse.com/forum/m_27..._2/key_/tm.htm
http://www.silentflight.net/modules/...hp?articleid=1
http://www.genie.rchomepage.com/FILE...R%20SYSTEM.pdf