LargeScale88

Hello. I'm currently building a Top Flite Giant Scale P-51 as a "trainer" for my Don Smith P-51. I know that there are a lot of things out of scale on TF models, and a few of them I want to fix up to make it look better.

The cowl droops way down in the front, which is because the engine centerline is way down low. Would it be possible raise the centerline like an inch or a little more? i imagine its lower like that because it improves flight performance, but not exactly sure. If I were to raise the centerline, would this change the flying? Handling characteristics? Would it even fly?

Thanks much!

Jason

Chad Veich

My Feedback: (60)

Jason,

I'm not 100% certain but it may not be that the thrust line is lower than scale but rather that TF is using too small of a spinner. This results in the top line of the cowl having to be brought down to match the smaller diameter which gives the appearance of a lowered thrust line. Somebody like Leo Spychalla or Tony Howard would probably know for certain since they are producing scale cowls for the airplane. At any rate, even if the thrust line is lower than scale, I can't imagine bringing it up a bit would hurt any thing. Good luck with it!

rcphotog

I agree 100% with Chad.

TopFlite and others have destroyed the appearence of my favorite fighter in oder to avoid using a scale diameter - thus more money- spinner.[:@]

This has frustraighted me for many years. If they would simply draw the nose to scale and let us buy the expensive scale spinner then we wouldn't have to buy those really large and pricey Comp ARFs........

Bob Holman used to offer a pretty nice "midscale" P-51 at I think 69 inches that was IMO very scale. I think it was a Brian Taylor design.

sorry for the rant.
Ken.

joey_snaproll

My Feedback: (32)

Hey Jason have a look here , Leo's cowl might just be whay your looking for. I have the cowl and razer back great products.

http://www.rcuniverse.com/forum/m_38...tm.htm#5377993

Joe

dvs1

I have Leo's cowl on my mustang and it's the only way to go! Much heavier and stronger fiberglass than the TF cowl, very nice scale outline. Plus it fits perfectly.

Spychalla Aircraft

My Feedback: (34)

Jason,

The Top Flite Engine and thrust line locations are fine. They just used a spinner diameter that is too small to save money. The Top Flite spinner is 5 inch diameter and it should be 5-1/2 inch to be scale. It is that simple. When you add the right size spinner to the front end it brings the curvature of the nose to scale.

Moving your engine up or down within a 1/2 inch or so isn't going to change the flight characteristics of this plane, yet that does not solve your problem because if you move it up your stock cowl will not fit and your chin scoop would look bad if you modifed it. So my biased answer is that you should just get one of my cowls and use a bigger spinner.

Leo Spychalla

dionysusbacchus

My Feedback: (25)

I've built 3 of the Gold Edition 1/7 scale P-51's and I never did like the 3 views they were based on, the nose has way to much downward slope. On the 1/7 scale P-51's I raised the engine center line by 1/4" to get a more scale nose shape.

I recently purchased a brand new Top Flite P-51B kit and started looking at the plans. The nose of course is wrong, but it's not just the spinner size. I consider the master of the Mustang to be Doss Steed, and I have his Mustang plans. Comparing the TF to his I needed to raise the TF engine center line by 1/4" to get the nose top profile right. Forgive my lousy drawing on the TF plans, especially my spinner that I drew free hand! If you are going to a larger spinner then the kit cowl will not work anyway, but raising the engine 1/4" does not change the lower fuselage shape at all, because the spinner is in the same place as the stock one at the lowest point. I will be making a lower fiberglass cowl and constructing the top of the fuselage basically as shown on the plans. With the larger spinner and raising the engine, a total of 1/2" is added to the top profile of the nose.

In the pictures I'm showing the Top Flite plans with a new cowl line that I quickly drew on to show, but the plans are very wavy from being rolled up for so long and the nose profile looks distorted a bit, but you can get an idea anyway of how it should look.

Luke

BobH

My Feedback: (2)

I built my GS TF Mustang when the kit first came out. I replotted the nose shape based on some good 3views I had. This resulted in adding some formers to the nose to get the shape correct.

There is more to the incorrect shape than just the spinner size. I think replotting is the way to go. Or get an aftermarket cowl.
You can leave the thrust line as is and have a reasonably good looking plane.

Besides there are other issues with the fuse than just the shape of the nose. The cross section isn't right either.

JeffH

My Feedback: (43)

The stab is too low, and to me, the canopy is way off in the head on and top view. Of course, the dihedral needs to be increased dramatically to be scale.

dionysusbacchus

My Feedback: (25)

True, but like any project you pick and choose and in my opinion and for my planes the P-51 nose needs the most attention on the Top Flite kits. It makes the most impact on the look of this plane, all the other not scale lines are nothing in comparison. I prefer to treat it as a sculpture and forget the plotting, after all this is a Sunday flyer! In any event if you want it to be as close to perfect as possible,(not my plan for this project) then I would pick another kit our build from scratch.

Raising the engine 1/4" is not hard to do! But as I said, it's intent is to give a great flying stand off scale plane a little more pleasing look, not make it a scale contender.

dionysusbacchus

My Feedback: (25)

How much are people raising the stab?

dionysusbacchus

My Feedback: (25)

On the canopy I can't see what you see, are you just talking about the front framework angles? I'm making a mold from my original, so making changes will not be a problem and I will probably move the frames around a bit. My canopy is also not clear at all, first Top Flite kit where I had a foggy canopy.

Merlin Man

Hi ALL,

In plan view, the TF canopy is way to "sharp" at the rear end.

I cannot quickly find any plan views at the moment of the TF but you will find that the full size canopy is much more rounded and wider.

Hope this helps,
Cheers,
M.M.

Luft-Gangster

Which version of the canopy are you refering to, the Inglewood, Ca versionsor the Dalas, Txversions? Remember, it was WAR, andNA usedmultiple suppliers.
see attached photo.

SVX

That's funny, we must be going through a Mustang phase again. I just got my 1/7 scale Top Flite down I started a few years ago. Decided to go electric. I too raised the thrust line though only 3/16". There is a definite line where the top sheeting starts and the nose blocks begin so I scrapped all the kit stuff and carved my own cowl out of foam. I will be making a mold and doing one from glass for the final cowl.

Dust

dionysusbacchus

My Feedback: (25)

Luft-Gangster, that is some interesting info, but we are talking about the B/C mustang canopy, specifically what is wrong with the Top Flite Giant scale Mustang canopy.

SVX, lol, I've been on a mustang kick for a while now! That thing is looking sweet man! Love the tail wheel also, I'm going to be using a Goldberg nose wheel retract for my tail wheel. Did you have a thread for this masterpiece? On my 1/7 scale versions I only had to raise the engine 1/4" to get the right nose shape, but yours looks awesome.

I think the 1/7 scale canopy is much better than the 1/5 scale, when I make a new mold for the 1/5 canopy I will do some reworking of the front shape and move the frames around a bit.

SVX, here is some inspiration to get that canopy working like it should! I use a small spring steel rod to latch the canopy closed, works great.

JeffH

My Feedback: (43)

Its tough to describe in words. If you look at it head on, the canopy does not seem "bubble like" on the sides. The sides are almost a straight slope from the top of the canopy to the fuse sides. It could be that the fuse is too fat in the middle as well. It looks like someone tried to stretch a skiny canopy over a fat fuse if that makes any sense.
I am referring to the D model, and it appears you are building a razor back so my comments do not really apply.

David Bathe

dionysusbacchus

dionysusbacchus

My Feedback: (25)

Yea, you are correct about the D canopy, like most D canopies they are also incorrectly tear drop shaped as well. But yea, I was talking about the B.


Thanks David, now I just need to finish this thing and move on to another P-51B! But at least I have all the details worked out for the big one, should be a piece of cake![8D]

SVX

Thank you Luke. No, no build thread, maybe a finishing thread we'll have to see. You are dead on as usual concerning the cockpit and yours looks great. The canopy isn't that far off until you get to the front windscreen. I wanted to have mine open as yours but after my P-40 I don't feel like building another full cockpit. Not to further derail this thread but have you decided on a paint scheme? I will be doing "Sweet Helen" from the 362 fs 357 fw.

Dust

Luft-Gangster

The B/C is my favorite version. I prefer the malcom hood modification.
Hope these pics help.

Luft-Gangster

Another interesting one.

dvs1

For myself to get better scale looks I'm happy with I used the spychalla cowl, an aerotech scale canopy kit, a stab relocate kit I can't remember where, and used aerotechs scale inner and outer gear doors. The only other thing that really looks out of scale on mine now that stands out is where the lower rear fuse and rudder bulge out. But if I had to pick only 2 it would be the cowl and canopy, the canopy itself is way off. The top flit kit is great for doing mods to, and is very affordable.

dionysusbacchus

My Feedback: (25)

Luft, those pictures are very nice.

No one seems to know about where the stab should be, but I will probably just use the Doss Steed plans to locate my stab anyway.

SVX, My 1/7 P-51B will be done in the colors of "Joan". I drew the nose art and sent all the info to the nice lady at Get Stencils and it all turned out great.

Merlin Man

Hi All,

Thanks for those canopy shapes Luft-Gangster. I have been a mustang "follower" for over 20 years and I have not seen these sketches before.

I was aware of the fact that canopies were produced in California and Texas but didn't realise that each produced slightly different shapes.

Can you tell me the reference for these drawings ? I would like to know more of the story as to why they produced these different shapes ?
( Maybe it was just a case of wartime rush and no real need to make every canopy mold exactly the same as the next one ???? )

BTW, my comment on the plan view I think would still hold no matter which variant.

Cheers,
Merlin Man.