brazan

My Feedback: (2)

Thanks
I will give that a try.

Riddle4U

Good question Brazan, one should check compatibility of any chemical (paint) on the substrate (what yer painting). You can use the clear (non imaged area) of the decal sheet, to test your potential paint choice. If it shrivels like monkey balls in Alaska...you may have something that disolves the decal. Try something else! Whenever you paint something slick, scuff the gloss off as previously mentioned, and wipe it with rubbing alcohol (isopropyl). That is a start..good luck!

CGAV8R

My Feedback: (2)

Hi guys, for those of you that are trying to fit 4" tires into the wing, you know that it is a VERY tight fit. I found the thinnest tires I could and built myself a set of wheels. Here is how I built them http://www.rcscalebuilder.com/forum/...129&PN=1&TPN=1

SIX GUNS

cgav8r, who's or what tire did you use ?

Riddle4U

cgav8r, I gotta say that does not look like a P-51 wheel (when being picky). I think getting a thinner tire/wheel does solve some problems for some though. We'll see how my Robart wheels tuck up (3 3/4"). I ground the Robart strut to squeze it in. I am hoping the Bob Violett retracts will solve part of the problem....

Oh yea, I got a question: What are people doing on a fiberglass layup for gear doors (glass weight, # of layers, weave bias, e.t.c.)?

CGAV8R

My Feedback: (2)

Close enough for me. I know the inboard side of the wheel has smaller rounded holes and I could have used another set of wheels for that, but hey, i like em.

Aaron D.

OSUAV8R

Hey Everyone,
     Just a quick update.  I have the wng done and the retracts mountes.. they work great, I may need to shim one to make them match perfectly.. but they look great.  The fuse is well on its way to being done.

Now I start thinking about glassing

Pics to follow soon
 
Happy Thanksgiving

CGAV8R

My Feedback: (2)

Sixguns, I ysed BVM Jets Mig 15 4" tires and 1/10 scale RC car rims modified to fit.

Riddle, I used 4 layers of 6 oz. glass for my doors. Dont use regular epoxy or finishing epoxy, it won't hold the shape. I used west systems epoxy and it worked perfect.

Aaron D.

Riddle4U

Thanks Aaron! I couldn't remember where the last good advice on the gear door layup was found (I shoulda taken notes). I am curious about the mention of epoxy/finishing resin issues with holding shape. I wouldn't have thought it made a difference, since epoxy-fiberglass layups are common with cowls, blisters, fairings e.t.c. (but I will consider your advice strongly). I also was wondering what the finished thickness is with your layup? My original plan was to use four layers of 1.5 oz. Sig glass and their resin for weight and thinness. Your doors look exactly like my planned outline, I was going to Monokote just the area where I see you have a dark line for a "release" surface (I am guessing that is what that line is also used for in your case). I somewhat narrowed the two inner partial rib locations to get it closer to scale (without loosing strength). I hope to add the inner door skins also, if they will fit, but I am a little doubtful there. I may have to fudge the inner detail on all the doors to get everything tucked, or just have to forget that altogether, if that is what it takes to get everything flush. Thanks for the pic, and also a number of people have given up on flush doors, let alone inner and outer doors here, so I appreciate any tips on how your experience went. I attached pics of my modified Robart struts (built up with brass tubing on the upper...brass clevises for door connection) - Eric
Happy Thanksgiving everyone!

gmohr

Aaron, those doors look great! Are they all one piece outer doors, or do you intend to cut them into inner/outer doors?

Regards,
George

P.S. My covering is almost complete. I'll post some pics once I have done.

Riddle4U

Gmohr, I wouldn't normally respond with another's project....but since I am doing the exact same thing, I am certain that those doors get cut into two pieces each (inner and outer doors). I plan to use a Jomar sequencing unit to electronically time the inner door operation with the gear retraction/extension. My main gear and inner doors are operated by two seperate micro servos on two seperate pneumatic (Robart) valves. The sequencer does this: upon selecting "gear down" the inner door valve and main gear cylinders are charged to drop gear and open inner doors simultaneously...then (with an adjustable electronic potentiometer) the inner door servo changes the inner door pneumatic valve to close the inner doors after the gear is down (this is per scale, and lowers drag with extended gear). When "gear up" is selected, the inner doors open and the main gear retracts. The timing of the sequencing unit (I used Jomar), then closes the inner doors to close up the whole wing. Hope that makes sense. This all works with one gear switch on the transmitter automatically! I imagine Aaron will have to do something quite similar. I hope he doesn't mind me responding on this...but I had been planning it all for quite some time. If you do not use the electronic sequencer you need to use another channel to manually close the inner gear doors (far from ideal). Note on pics of the real Mustang that the inner doors hang down when plane is parked; this only happens after engine is shut down and hydraulics go away (then the inners fall). Normally the full scale inner doors pull into the up position while on the ground after engine start. Hope Aaron forgives me for my explanation on my similar plan.

p.s. Note inner door position in each of these pictures..should clarify.

CGAV8R

My Feedback: (2)

Riddle, first I tried 6 layers of 2 oz. glass layed up with 30 min. Z-poxy. You can see the result of that layup in the pic. On the second layup I tried z-poxy finishing resin epoxy with more layers of glass, that didn't work either, still too flimsey and way to thick and heavy. I finally bought a west systems epoxy kit from Aircraft Spruce and Supply. http://www.aircraftspruce.com/catalo.../westepoxy.php
The kit cost 39.00, plus I bought a set of mini pumps for 8.00. This may sound like alot of money for epoxy, but you it's close to the same cost of buying the small bottles of epoxy for the same quantity. If you are going to glass your plane, west systems is excellent for that and any glass layups you want to make. I guarantee once you try west systems for glassing you will never use anything else. Most of the epoxy-glass layups you mention in your post are probably done with west systems or other epoxy designed for layups and molds, not the epoxy stuff we buy at hobby shops.

I have used the monocote under my layups before, i prefer to use plain old saran wrap instead, it works better.

My doors are .044" thick. Stiff and light.

I went the simple way and put a servo in the middle of the front wing ribs to operate my inner doors. I can either use a switch on my radio or a sequencer to operate them.

Gmohr, if you look at the pic closely you can see the red line where i seperated the inner and outer doors.

Aaron D.

Riddle4U

Aaron, I am familiar with West Systems products by name. They have been around (I think they are a marine product...and well suited). So, I'll go with four 6 oz, matt layers (unless there is any other input here). Thanks Aaron, I have been a little slowed by this point in my project. I also have some PVA release I was going to mask and spray in the larger area I was going to glass. If Saran wrap does the trick, I'll spare my spray gun a "clean up" and just tape Saran to the area. Let us know how your total installation works out! Gobble gobble, all. - Eric

gmohr

Hi guys,

Quick update, I've gotten the covering complete on the airframe, save the ailerons and flaps. Slow progress because of the holidays etc, but hey next spring isn't coming very quickly

-George

P.S. Curse you, black monokote, you hater of all things good.

Riddle4U

Looks great George..don't know about the evils that black Monokote can do though? Funny. I am going to finish my ol' Stang up due to this thread though! Hats off to all us TF Stang builders. Yea, were building! BooYah (to quote Jim Kramer)! -Eric

gmohr

It's what it *doesn't* do... which is shrink like it is supposed to. It would take a flamethrower to make that junk shrink the smallest amount. I swear I'll never use monokote again, and thats a shame because I really like the finish and have used it for decades.

Riddle4U

gmohr, I have had some disappointment with Monokote. It seems it has changed over the years. However, I must say that one has to do one's own part in skillfull application. One must take utmost attention to sealing the material tight before hand, and not expecting the material to counter sloppy application. Monokote really is still pretty good. We are getting lazy, I find, in our skills. I wonder if Monokote is deteriorating in quality? Just the same, they have nice colors, and a decent material. Learn to work the material is all I can say, I work with it succesfully. You can't expect to have the shrink make up for poor application, that is asking too much (nothing to say your application is poor)!

gmohr

The problem I have is the inconsitency. The bulk of what you see (aluminum/white/red) goes on just as it always did. The black roll I have, however, simply refuses to shrink. Not one bit at all. so if you have the slightest wrinkle that you want to shrink out, when you apply heat to the area, it simply wrinkles more. Apply more heat and it starts to wreck the nearby covering. But it will not shrink at all.

I've seen complaints about this behavior and always wrote it off to people expecting MK to act like Ultracote or something from China... until I saw it myself...

Regards,
George

CGAV8R

My Feedback: (2)

Yes, monocote has changed over the years. I hate using it now. I prefer ultracote now, that stuff shrinks great.
Aaron D.

bravosierra

Hey guys, I am new to this whole forum thing but I'm going to give it a try and hope that this thread continues through the build of my TF P-51. There is an amazing amount of invaluable information on here that I know will help me through this build. What ever did we do before the internet? Anyway I don't have a camera at the moment so I won't be posting any pictures until santa leaves me one under the tree. I just started building the kit a few days ago and so far only have the horizontal stab completed. I hope to get started on the vertical fin tonight. I have decided on the "Obsession" P-51 color scheme after many hours of going throught the Mustang Survivors website and looking at hundreds of pictures. Iwill be installing flaps, retracts with outer doors only, dual aileron servos thanks to the advise Ifound through this forum, and an O.S. 1.20AX or .95AX (not sure yet which one). The P-51 has always been my favorite airplane so I couldn't be more excited about this project. Years ago I had a .40 size P-51 that landed like it was made of bricks and mortar. It wasn't very scale but in the air it did look pretty darn good. You just had to remember that landings needed to be FAST or it would drop like a stone. I am hoping that the TF P-51 is a little more forgiving. Anyway, happy building everyone and let's keep this awesome thread going.

Riddle4U

Welcome to the internet world Bravo. You'll find good advice as well as not so good advice here. You'll still need to use your noggen! Most WWII warbirds will fly like a brick with the power off..for sure (just like the real ones). Don't expect a different performance capability...these are warbirds, and they fly similarly to their real counterparts (i.e. not for beginners whatsoever). Make sure you are the master of a challenging sport plane first (and one with a high wing loading). When you try to fly these models like modern aerobatic offerings...you will receive a snake bite! Mustangs didn't turn 1000 degrees per second roll rate (some of our current aerobats do). They just don't perform that way. They land pretty fast (you better be good on a taildragger too). Because they are heavy for the wing area, they'll stall at a higher airspeed. Totally different flying method from aerobatic sport models. The longer the runway..the better! Good luck to you, it sounds like you're making progress.

bravosierra

I guess I should have been more clear in my previous post. I'm not new to the internet by any means and I have looked through a lot of forums for information but I have never actually joined one until now. I think (and hope) I will be able to manage the flight characteristics of this model. Although I have been a bit discouraged by some of the posts I have read on here about maiden crashes. I do have quite a bit of tail dragger experience and have successfully flown a couple models with high wing load, my .40 size bricks and mortar mustang being one of them.
   Anyway back to the build. Last night I got a good start on the vertical fin and rudder so now I just have to plane and sand them to shape. My 11 year old nephew is coming over for the weekend and I am hoping to get him in on the building a little. He is already interested in the flying part of the hobby, now I need to get him hooked on the building as well. We need the next generation to keep the building part of this great hobby alive and hopefully we'll see fewer and fewer ARFs out there.

 - Bryan

Riddle4U

My Bad Bryan! Well, nice idea to bring your young nephew into the building...I hope that pans out. It used to be, you pretty much had to build if you wanted to fly anything other than small electric toys. So we all had to build, but I found I liked that part just as much as the flying. People expect instant gratification nowadays..so I don't think the ARF's are likely going away. Maybe we can just hope that everything doesn't come as an ARF, and that some of us who enjoy building can still find kits. One can always build from plans though (as long as balsa suppliers stay in business..anyway). I hope there'll be engines available in the future, every guy who puts in an electric is one less engine sold. We have already lost a lot of companies (and the healthy competition between many engine makers). Other than that, many of the products that are available today, are certainly terrific. So let's keep up the interest in these kit-building threads, I think that may help reinvigorate building! Before these forums you just sat sanding away all by yourself in the work room with sawdust in the hair and CA glue stuck all over the fingers (that may still be true)! The motivation of like-minded modellers is a help though.[sm=teeth_smile.gif]

gmohr

Gah! I'm two ailerons short of enough Aluminum MK to finish the covering... one more tower hobbies order heh, my wife won't be pleased.

clwwaco

Hi everyone, I am building the topflite p51, and i also bought the B conversion from topflite, Has anyone built the b version with the extra kit. Any info is appreciated. Thanx