Riddle4U

Jeff, I look forward to getting those scale rib profiles. My posts are sometimes so long that basic information can get lost. Yes, it is clear that the scale ribs require a thicker spar plan.

Richard, you know I have desired the most scale landing gear possible. I just don't want to hold up the whole project until that is accomplished. If Jorg or someone else can eventually make something like that I would be interested. It could easily go for a couple thousand dollars to get it right maybe three thousand. A full scale radial would likely run 15,0000 to 25,0000. That's no joke, I have seen really full scale functioning Merlin engines for even more than that. My point is that to build this thing exact to the nut and bolt may be outside the scope of this thread? The best scale contest winners frequently make compromises. A 5 1/3 wheel may fit after we get the scale ribs done, we'll see. I just think if the gears we have available make that fit essentially not possible, I wouldn't hesitate to nix the thought.

That's great advice Danny, I feel dumb as that probably is the solution. Now....where did I find that file in the first place?
It is maybe five pages with a bill of materials and all.

rwright142

I am not suggesting we build every nut and bolt. The goal is "to build the finest, most detailed, and as historically accurate a Corsair they can." I'm suggesting that WE CAN do better.

For example, if I hear, "a 5.25 inch wheel will not fit because of X." I'll suggest we look at X to see if it can be changed so that we CAN have the most detail. Keep in mind that I have NO, zero, zip, zilch experience with retracts and I apologize if I am the one slowing things down because of that.

We started with Royal plans and Matt drawings and others, but they were only to be used as a guide. We have made and will continue to make adjustments as we move forward.

I'm not the sharpest knife in the drawer and need further explanations at times I appreciate everyone taking that into consideration and putting up with me

Riddle4U

I admire your fortitude Richard...ha ha ha ha! I was thinking we should get through a first iteration on our builds, detail them all the best we can, fly em, compete em, and crash em! Then those of us that survive will keep this thread going to an even better one. We will all learn a lot through this process that can be applied to further scale models, and yes probably another Corsair. I just kind of nudge us to keep moving so we can have the fun of finishing one in the next year or so, and with all the nice finish and weathering...whatever. Let's just keep moving is all.

Richard I have been in contact with a sourcing agent on the cowl. They want drawings, and I said right now..for the "request for quote" I could take a pic of the Royal plan in the cowl area with some basic dimensions. This may be a wrong path, for cost reasons, but I thought I'd see what kind of quote's I might get...couldn't hurt. This same agency may be an avenue to get a quote based on Jorg's work. We could reach agreement with Jorg on a royalty to be paid on top of the cost to produce the gear? This is forward looking, and might more be applied to that "second Corsair", I think. But that next one really would be better if we can just get through this first one, and learn.

Remklep

Guys,

I'm at the point with the fuselage build that I have to choose which servo's to use for the elevator and rudder.
I use a servo-torque calculator that can be found at [link=http://www.mnbigbirds.com/Servo%20Torque%20Caculator.htm]this[/link] link.

I calculated the torque needed for the rudder to deflect 25 deg. (scale) at 250 km/h, this came to 330 ounce.inch.
Accordingly the torque needed for the elevator to deflect 20 deg. up (scale) at 250 km/h is 220 ounch.inch.

So I was thinking of using a Futaba S 9157 for the Rudder and a Futaba S 9156 for the elevator.

What do you guys think?

Chad Veich

My Feedback: (60)

Good grief Danny, you planning on using your elevators to pull stumps! I've flown much larger and heavier airplanes than this and I don't think I've ever used an elevator servo with more than 90 or 100 oz/in of torque. No reason you can't use them obviously but I certainly do not think that anything near that heavy duty is required. My .02 cents anyway.

Remklep

LOL
I was planning on using the servo's to crank up my car to change a tire...

I always tend to overengineer my planes
The torque was calculated at 250km/h at full deflection, I doubt the rudder with just 2 Robart hinge points would survive that.

Hmm, if I use the Futaba BLS-352, I can even save some weight and I have 2 of these in stock :-)

On another note, my LHS had an auction yesterday where they increased the discount every half hour by 4%, so after 8 hours (34% discount) I made my move and bought some stuff for the Corsair, which will essentially be free if I sell the Futaba FX-30 2.4 transmitter I also bought for the reglar price on ebay

Danny

Riddle4U

Not to get us off on a tangent (I think annecdotal advice from common usage will eventually guide our servo recommendations), what calculations did you use on the servo requirements Danny? There is a site that has a computer for servo selection ( I haven't ascertained how valid they are). I will try to find it. Just curious on how you arrive at calculated results. I think there is a lot out there on picking servos, in general though. What possible changes do the people doing the beta fuse build suggest?

I was thinking a bit more on the gear. I think there are some modifications to the Aune design which might bring us to a happy medium on gear selection (the mechanism itself would need to be changed as well somewhat). Hopefully they allow a nice machined set of scale drag links, lift (or squash)mechanism, scale strut, and better overall fit. They would still be pneumatic (sorry Richard). Pneumatic is the simplified version of the scale hydraulic principles of course, and lighter then hydraulic (think of a pneumatic cylinder and tank full of hydraulic fluid on our models). It would be quite heavy, and have a risk of dumping fluid all over our balsa structure..not good. I have some experience, as I converted my Rhom retracts to actual hydraulic in the '80's with "Hydralocks". It did work terrific, but the fittings are not up to par, nor the hoses (mine eventually broke down; cracking all over and leaking..after a few years). The retraction speed was excellent scale appearance, and the up and down lock were improved enormously. An electric gear would involve the weight of just one more battery on board (not insurmountable of course). If Jorg ever did do an ultimate gear I would suggest going the extra mile with an air-pressurized hydraulic system (electric hydraulic pumps is just going too far). Straight pneumatic would be OK too with a good restrictor design. I could suggest the Aune mods with some drawings eventually, at least we are starting with something. Basically one major problem with the Aune is that the air cylinder gets in the way of the drag links. I am still more or less behind the two main designs being: Robart and Aune. As I discussed with Richard, if we design a more or less scale area for the gear, the structures required for various other options are fairly simple.

WhiteRook

My Feedback: (38)

has anyone considered seirra gear?

Riddle4U

Yes....



...but not to go further...I think we've really gone deeply into all the mainstream suppliers. I think when reading the last 50+ pages, it keeps going to the gear, and to the exclusion of many other topics. Did I mention Gene Barton...(Oops). Thank you Whiterook! I am suffering from metal fatigue.

Really no offense Whiterook, but when you do read all of the thread, the same things get resaid including mine (I am as guilty as anyone, or more so, in other words), all the time. That IS an LOL. I wish a few would just say "yes, let us revisit this gear thing again in a couple of years" (not literally).

In the mean time: Cowl, I am working on quotes. Canopy, I would like some talk of building vacuum boxes and techniques. Cockpit, Richard has it going on pretty good (and we had some neat conversation on panels awhile back). Flaps, Chad is working on a dummy center section (should be monstrously helpfull). Overall airframe, we all need to get a conversation going with Chad. Now, that is what I would like to here chiming in on!!!

I forgot TW's, has everyone bought or built one (not me yet, but trying to find the file). Eventually we can talk about glassing and finish, then surface detail, then paint matching, then major markings, then military stencils, then weathering if chosen, then radio set up, then pre-flight suggestions, then.....fried chicken!

Riddle4U

In light of my itemizing some tasks in the above post, I have some possible bad news. I say possible because the provider of the Viking kits which Richard began his nice cockpit with, are basically not available now. I was able to purchase his last packaged 1/6th Corsair cockpit kit. This kit is just possibly the nicest start to a good cockpit; with less effort than starting from complete scratch. I think that would appeal to people here. With Richard's permission I will post the kit and Richard's extra skill in making the most of it as a basis. If you are wondering why I bring up a product which is non-available, it is because I got the indication that just "possibly" it could receive a little production run for us. I would have to let him know how much interest is in it. I get the impression (maybe my own perception), that perhaps he might make this available at an unknown date, if it was worth the time. No promises from me or him here, I want to make clear. If people PM me with interest I will tally it for purpose of discussion with him, and I would guess if it were more than a handfull interested, he just might find it reasonable for him to do. I will not quote a price, but it is quite reasonable I would think. So, if you see these pics, and are interested, weigh in by PM to me quickly. I will give it a week to tally the list (include how many kits you want); and if I could afford more than one immiediately I would do so myself. This really is a good foundation, and if you only want to use some of the parts it is still an advantage I think. Again, no promises of him making any more at all (this effort is only to possibly motivate him to make some). I bring this up for the advantage of our interested, regular, thread participants. I gain nothing personally. Pictures below:

Please remember Richard has added some personal scale modeling skill to the kit, including some gas cylinder detail in the picture I provided of his work. I am sure he would be helpfull in advising any on bringing your kit to a higher level as well!

Also, the thread "Brian Taylor Corsair-going for it" is the thread Richard started over a year ago on his Corsair aspirations (including a cockpit tutorial). I recommend everyone visiting or regular here read it through. It happens to be just part of the foundation for how we built this thread, with the addition of conversations RW, I, and others had with Luke about our desires. That is history, but I have to note it, with all due respect to Luke on the 1/6th Royal. Somewhere in cyberspace one might find Luke's Corsair thread (so due credit given), we are on our own here for better or worse though. Somehow there was a divergence of opinions giving birth to what we all read here. This is just a reminder, as many know this.

We are nearing our one year anniversary on this thread; so all that care can privately clap their hands! I hope we will all make substantial progress this year (bad economy and all)! I will suggest any other participants here who have been loyal to our philosophy, weigh in with anniversary-like wishes! - Eric

SMUGator

Hi all,

One of the guys reached out to see where I've been, so I thought I'd drop in and say hello. I've been keeping an eye on the project. I have been doing a lot of building - just not on RC Airplanes. You can see our continuing restoration of our 1939 motor yacht [link=http://www.facebook.com/album.php?aid=55593&id=564988878&l=c3c12ea14a]here[/link]. By the time we re-launch in early May, it will be time for golf, cycling, boating and flying seasons. With any luck, I'll pick this project up again in the Fall. Can't see it happening this summer. I do still watch weekly, though.

Keep up the good work.

Tom

Riddle4U

Tom, excellent work on the boat! Like I told ya, I am a sailor mainly; but love any classic wooden boats. Nicely done! Come join us when you are back into it. I appreciated your input; along with others here I am sure!

Riddle4U

Hi all, I am going to just give it a few more days on gathering a group for buying this cockpit. Richard will tell you it is a decent start. I just want everyone to have a chance at it. When it's gone, I haven't found a better one!

Jeff, have you lofted those airfoils yet! I think some could just take off with honest building with that contribution. When we get some people actually building here, the thread will be vastly enriched!

So, I haven't gotten anyone to respond with the tail wheel plan file link. I don't want to have to read this thread for days again (I would take better notes though). Chad? Those drawings looked to be your quality work?!? I am stocked and ready on that project, my cockpit is coming too (that'll take me half a year on the side). I am ordering the fuller sized Matt drawings so I can do some scaling on my own. I WOULD suggest many do the same.

Chad Veich

My Feedback: (60)

Eric,

Send me a private email and I will reply with the tailwheel drawings attached.

[email protected]

NCIS

I know this is for the specific model Corsair your building but I just had to show this one of mine off. It's a F4U-5N 1/4 scale 122" Corsair. It's about a year away from being finished and glassed so I thought I'd give you a look see! Even if your not building this model you have to like it at least a little.

Gibbs

Riddle4U

That's a neat 1/2 scale riding mower I see behind it too!

NCIS

Riddle,

Thats not a riding mower, it the Corsair's Tug!!! I didn't notice how big this thing is until you said something. Thats funny.

Barry

Riddle4U

A hopefully helpfull tip: The Paul Matt books and drawings are available from "Wind Canyon Books" online (Google it). The Corsair is in Volume 2 of the book (terrific book of many drawings). I have had the book for a couple of years, but just now found their website and ordered larger Matt 3-Views of the Corsair (I think 18-24" or so). I would suggest buying the books (there are two volumes), and any larger prints, while they are known to be available. These things notoriously disappear when you want them the most! That is one of Platt's rules.

jmodguy

My Feedback: (4)

Sorry I haven't posted for awhile but my home PC is on the fritz... I should have it back up by the weekend. Once I get it back up I will focus on the ribs I promised. back to work.... :-(

Jeff


4/2/09
I'm up again! Had to send a license request to Compufoil. Should get it tomorrow. Eric is pretty quick to respond.

Jeff

Riddle4U

No problem Jeff, I am looking forward to your work. I am just curious about how it may solve some gear-tucking issues. I know I did a pretty honest check next to a sample rib on my Royal plan, and my gear (anyway) just barely fit. I know our stuff just rarely works to zero tolerances, so I would hope for some breathing room in the design. Randy seems to show, as I remind, that his Robart tucks away pretty nice.

Can anyone give a bit better qualitative distinction between the Solartex and Koverall? I am familiar with the latter, and it is pretty good. I just liked the sense I got from looking at Danny's rudder, with the material. Where do you get it (I know it must be pretty ubiquitous)? One only needs a pretty small amount on our model, after all.

Riddle4U

I just ran into something that may be interesting. I was at the Glennis site, and noticed a tiny "micro-add" by Glennis stating that they were revisiting their "super-scale" gear program. I don't know exactly what that means, but my impression was that they were offering to make custom work in that regard. Well, I guess they didn't see us coming before they made that notice[sm=lol.gif]. I hope they could help though.

Richard, maybe you could ask Jorg if he could translate his data into part by part drawings in 1/6th scale? I am interested in a really nice gear after I cut my teeth on this first iteration! Also the sourcing company I mentioned is a clearing house for bidders on projects with provided drawings (I have already submitted a simple cowl drawing that will result in a good outline). I would also like to get bids from non-hobby outfits on this gear! We could just submit the darn Vought drawings to them and say "make it 1/6th real size" ha ha ha! Not entirely joking, the prime mover (hydraulic or pneumatic ram) can be made by Clippard to custom specs as they offer, and that could be placed in the scale location per Vought drawing (or have the bidder machine the prime mover also). We can spec it out with T-6 aircraft aluminum or whatever, try to standardize all the bushings out of brass to similar dimension, and simplify it just a bit on actual shrinking of smaller scale parts (reduce parts count a little).

A little more down to earth...they could modify the Aune design (improve it), and get a good result I think. For the links to work at all (fit), and look scale, the Aune design's air cylinder needs to move out of the way. If we just have that actuation be accomplished remotely from the retraction mechanism itself...the links can be modified in to the design easily...and Richard, you (or any of us) could actuate it with air, hydraulic cylinder, good retract servo, Lado equipment...whatever! You know (and we all have a zillion pics now), the direction of force needed (as applied by the current ram). We could machine a nice belcrank and get the cylinder placed more "out of the way" at a 90 degree angle outboard (or servo pushrod or Lado jack screw). The only problem is the only straight shot puts this prime mover outboard (where the wing fold is). Not a problem for me now (ball links or something). If you move it inboard the darn gull shape won't allow it as easily, maybe, but could be done. In fact, I think I just envisioned the design while writing this!

pappy 883

My Feedback: (2)

Riddle, I have a set of Earl Aune gear for my 1/6th BT Corsair and the air cyl. is not a problem. It measures 2.83" from the cyl.base to the air fitting. I'll bet your cyl. is longer than that....am I correct ?

Riddle4U

Pappy, my cylinder is 4 inches long for whatever reason. I spent four months communicating with Earl on a special gear with exact scale drag links. The set he finally sent me was unable to resolve a design with ANY combination of air cylinders that allowed full scale drag links per Vought drawings. I was willing to spend upwards of a grand on a gear that was more scale. I think his is probably still the closest to scale of any, but many here are not satisfied with current level of realism in Corsair models. I.E, the BT for instance was considered totally unacceptable as a platform for our project. Other areas we have tried to address as well including the gear, e.t.c.. I think we are kind of still grinding away at some of these issues. There are quite a few pics of my Aune set on this thread Pappy if you wanted to propose any ideas, for me or others. Good to here from you by the way, how is your Corsair?

Yea, Pappy, if you have any pics of the Aune you are utilizing with some solutions, please share them. I don't know why Earl wouldn't have come up with something better if you have found something?

pappy 883

My Feedback: (2)

Riddle,
I share the same quest for scale accuracy that you all do . But I found that at some point I had to be realistic and comprimise between scale accuracy and a good solid design that works well and looks good. A perfect scale set of gear would be wonderful but it problably would not survive the first landing or would require constant "tinkering " to get them to work properly.
The 4" air cyl. on yours should be replaced with the 2.83"so as not to fowl into the main spar and tire. Have him mount the air fitting on the side of the ram not the end for more spar clearance. As for the draglinks, this can be resolved I'm sure. I'll get mine out of mothballs and see what I can do .
Richard, if you read this, please post that pic of the drag links on the Oregon Scale F4U-5N. It had one of many solutions.

Riddle4U

Hi Pappy, I spent last night rereading Richard's original BT thread. His cylinders are shorter and fatter. I noticed RW did have the cylinder going past the BT spar anyway. Hmm... I am just concerned about the spar for our Royal plan. I think if I just get some precured carbon plates cut to the spar plan and laminate both sides of the spar it should be OK? My narrower cylinder actually may allow making a hole instead of a bigger horseshoe cut-out. I have spent over an hour a week ago looking at the Clippard pneumatics site. I found my cylinder, and probably the one everyone else has. Can I get someone to give me the part# on their Aune gears? Mine is SDR 12-1 (on the machined end of the cylinder-very small). By my measuring, the 5" wheel will fit mine as is though. Earl did mount the air nozzles to the side on mine. One thing, my cylinders are narrower..could be an advantage clearing the links. Probably why he did that. Force on a ram is proportional to the area of the piston face, so I will have less force. That is a concern.

I agree Pappy, on your comments. I guess I just think forward for the next one (Corsair) and some seem interested in the next step for a scale gear. I am going with what I got, and if I can't get a reasonable link going..I won't worry about it for now. You must have some progress on your BT since what I saw on Richards old thread?

Oh, and I don't have contact info for Earl anymore. He must have moved, his e-mail didn't even work. I am kind of on my own unfortunately. I think he has a new employment gig and isn't, maybe, doing so much with his hobby business. He is a nice guy, and I hope others can get his gear somehow in the future.