Monogram F7F Tigercat noseweight

[peter havriluk]

I just took down this kit to commence work. Anybody have an idea of how much weight to stick inside the nose so it can sit on all 3 landing gear legs without a tail prop? I'd like to install what I can before joining the fuselage halves and sandwiching the nosegear in place, which I think will thwart my adding weight after the fuselage is joined.

Thanks very much.

[Jennings]

Tape the major parts together. Put your fingers where the main gear struts will go, and see how much weight it takes. I've been building models for nigh on 50 years, and I've yet to ever actually weigh the nose weight I've put into one. Not even sure how you'd do that unless you had a really sensitive scale. Throw in as much as you need, then a little extra for mom, some for the kids, and a little extra for grandma.

[Slartibartfast]

^^ Wish we had some sort of like feature here. Good rule of thumb.

[Tailspin Turtle]

I just took down this kit to commence work. Anybody have an idea of how much weight to stick inside the nose so it can sit on all 3 landing gear legs without a tail prop? I'd like to install what I can before joining the fuselage halves and sandwiching the nosegear in place, which I think will thwart my adding weight after the fuselage is joined.

Thanks very much.

My technique is a refinement of Jennings':

The triangular piece of wood is the corner reinforcement from a Clementine fruit box that is placed where the main landing gear wheels will be. There is a paper box at the front for the weight. The blue lid under the tail holds it at the "sit" angle when it's on its landing gear. I put weight in the box until it tilts forward and add a bit more for good measure (too much risks landing gear failure). The "sit" angle is important with airplanes that sit nose high like the F7U Cutlass.

That said (and speaking from experience), the Tigercat, like all propeller-driven airplanes with tricycle landings gears and especially so in its case because it was inclined to tail sit , will need all the weight you can put in it forward of the main landing gear, including the engine nacelles if I remember correctly. On the Minicraft T-34 I even had to put a tiny piece of lead in the propeller spinner.

[peter havriluk]

Thanks, folks. think I've been offered enough insight and techniques to carry on. Right up to the time the nosegear collapses...

[dnl42]

Thanks, folks. think I've been offered enough insight and techniques to carry on. Right up to the time the nosegear collapses...

It's the MAIN GEAR you need to worry about. The nose gear will see very little weight.

[Paul Boyer]

The first one I built had the entire nose forward of the cockpit and above the nose-gear well, the engine cowls, and the front half of the centerline drop tank filled with lead shot, and it was barely enough to balance the model. The second one I did, I pinned the gear to a simulated PSP groundwork on a wood base. In real life, in Korea, some on the flightline had a 55-gallon drum placed under the rear fuselage to keep the tail out of the mud.

[Rex]

Another way to do it if you intend to do more than one of any certain model kit.

Use pennies (keep track of whether they are early or late, if you are in the US).

In High School, we had balance scales to weigh out chemicals in chemistry class, use something like that. Once you determine how much weight you use, "balance" it with the pennies. Then when you go to build it again, you'll know whether you need 5, 10, or 17 pennies worth of weight to put in that nose for your next build.

you can make a balance scale yourself, just use a piece of plastic card, put two cups on it, and fill both sides with the same vintage pennies,,,,,,,,,when you get it to balance on a piece of round styrene, glue the styrene right there. you now have a home made balance scale. write down the number of pennies for that kit, and you can fill the cup with that same weight of lead shot.

Then it is a simple matter of finding space for all of that ballast, as Paul said. Some kits don't give us a whole lot of space to put that weight into. Metal nose gear can help with the balance, as can some of the metal nose gear wells. Metal main gear can help support the weight, as has been said, that is the weak point with all that extra weight.

[Tailspin Turtle]

It's the MAIN GEAR you need to worry about. The nose gear will see very little weight.

While it's true that the nose gear sees very little load statically, it is vulnerable when someone sets the model down clumsily so the nose gear hits the table first and at some speed and/or with sideward motion. Then the heavier the model is due to too much nose weight, the more likely that the nose gear will break. Like the real airplane with tricycle landing gear, always touch down with the main gear first, at a low to moderate sink rate, and with no sideward drift.

[peter havriluk]

Thanks, folks. The more I mull about this question, and the more response I get, the closer I get to making up a tail prop. I could even repurpose the display stand the kit came with. And making a prop out of clear acrylic is easy enough. The landing gear, while sturdy enough as plastic goes, will be well-nigh-irrepairable if any breaks occur. And these shelf models do get moved around a bit from display to storage and back.

And I hadn't considered which landing gear components were at risk. I'd mentioned nosegear, but someone mentioned the obvious-if-you-think-a-bit fact that the nosegear would be the least loaded of the three.

[Joe Hegedus]

While it's true that the nose gear sees very little load statically, it is vulnerable when someone sets the model down clumsily so the nose gear hits the table first and at some speed and/or with sideward motion. Then the heavier the model is due to too much nose weight, the more likely that the nose gear will break. Like the real airplane with tricycle landing gear, always touch down with the main gear first, at a low to moderate sink rate, and with no sideward drift.

I'd argue that that scenario is completely independent of any weight added to the model. The same risk applies to any model with a tailwheel that is clumsily set down tailwheel first, or any tricycle gear kit that doesn't need any additional weight as well. Someone being a klutz is a risk to any model.

[Joe Hegedus]

Monogram's Tigercat isn't too hard to get to balance. The whole nose will need to be filled with weight (I used lead birdshot) and the volume in the nacelles forward of the MLG well and behind the engines as well, but it'll sit without problems then. In the nacelles, I put a bulkhead at the forward end and filled the area ahead of that with more birdshot.

[Rex]

The problem gets bad when you do a conversion.

To be Tigercat specific, if you convert to an F7F-2N, you lose balance (and ballast location) twice. The resin nose seems like it would help, but, resin is lighter than our metal ballast methods, so it actually takes away some of the "lead volume area" that you started with. Then to make it worse, you add the Resin rudder out back, which is of course heavier than the plastic part.

"Upgrade" with the resin engines and cowls from Quickboost, and you lose a lot of that area for placing weight.

We need a range of white metal pilots, and white metal engines and props for some of these tricycle geared aircraft.

Or a range of boarding ladders for each aircraft type that needs a prop for the tail.

[Joe Hegedus]

The problem gets bad when you do a conversion.

To be Tigercat specific, if you convert to an F7F-2N, you lose balance (and ballast location) twice. The resin nose seems like it would help, but, resin is lighter than our metal ballast methods, so it actually takes away some of the "lead volume area" that you started with. Then to make it worse, you add the Resin rudder out back, which is of course heavier than the plastic part.

"Upgrade" with the resin engines and cowls from Quickboost, and you lose a lot of that area for placing weight.

We need a range of white metal pilots, and white metal engines and props for some of these tricycle geared aircraft.

Or a range of boarding ladders for each aircraft type that needs a prop for the tail.

In that case, I'd just revert to the plastic tail prop included in the kit. It's clear and fits under the aft end of the centerline tank so it's not too obvious. Or, one can scratchbuild an extended tail hook from metal and use that to hold the tail up. That actually worked quite well with the Planet XTB2D-1 Skypirate I built a couple years ago.

[Slartibartfast]

Another way to do it if you intend to do more than one of any certain model kit.

Use pennies (keep track of whether they are early or late, if you are in the US).

1982 was the transition year when the U.S. mint changed from copper alloy to copper-plated zinc and both types were issued that year. The zinc pennies are lighter but not enough to feel. I can usually tell by looking at the patina but I'm a lapsed coin collector and spent quite some time weighing the little buggers. Keep it simple and use only 1983 and later pennies as the pre-1982 coppers are becoming scarce.

[PFlint]

Someone being a klutz is a risk to any model.

mmmm..... sounds to me like that should be model building rule # 1 ! :thumbsup:/>

[scimitar]

Hello All,

Well, you could just leave it on its tail if there's insufficient weight in the nose! Just check this photo of an F7F night fighter of the USMC in Korea, sitting on its tail bumper.

The standard single seater might also sit on its tail at times, though I've never seen a photo of one doing so.

(Hope the link works!)

https://www.google.com/imgres?imgurl=http://3.bp.blogspot.com/--n9_KIEYZfQ/VEathQOJgNI/AAAAAAAAABE/3efj1PEpgE4/s1600/IMG_1229.JPG&imgrefurl=http://www.akamat.com/2014/10/a-big-beautiful-blue-cat.html&h=669&w=1023&tbnid=gGhDkVil9CxucM:&docid=_Yx7V61YLPUGdM&ei=2KbgVqrEHsb3-QHQ0ZPADQ&tbm=isch&ved=0ahUKEwiqkPTO1rTLAhXGez4KHdDoBNgQMwg5KBQwFA

[Rex]

Hah, anyone else tempted to build a nice crushed coral base for a nightfighter, and glue the thing down on the tail? Just to stand back and see how many people try to "help" by trying to stand it back up on the nose gear?

[echolmberg]

mmmm..... sounds to me like that should be model building rule # 1 ! :thumbsup:/>/>

Rule #1 about model building is you do not talk about model building.

[Mistral]

For my build of this aircraft, I filled all available space I could with lead (including the nacelles) and it was still a tail sitter. I guess I just missed a gram or two. So now not only is it heavy, it has a clear spree tail prop.

[dnl42]

Dang. I need to drag this one out of the stash and put it in the next up list.