B-26 from Hasegawa in 1/72 - how much Wright add?

[Sebastian _SJM]

Hello good people.

I have a question:

How much weight I should add beetwen cocpit and bomb-bay in B-26 from Hasegawa to avoid tail sitting?

[gingerbob]

The usual answer: enough.  I always just "dummy assemble" the big bits, and then start approximating.

[FinnAndersen]

Just a thought: you can use less weight if you can manage to shift it forward, ideally as far forward as possible

 

I have alway dreaded this problem as in my experience, to avoid a tailsitter, you need a lot of lead, leading to a very wobbly undercarriage that threatens to collapse any moment soon

 

yes I know that its not the kind of answer you wanted, but if it helps you to avoid my kind of issues...

 

 /Finn

[Graham Boak]

If you place your model on a base you can drill two holes in the base where the nosewheel is placed.  Then you can loop a piece of thread around the nose wheel axle and knot/glue it together underneath the base.  The thread will be barely visible once complete.

[kev67]

Dry assemble the model with all the tail and wings, engines on, just use tape to hold them in place, then just add weights to the top that are taped on as well, then it’s just a question of balancing where the main undercarriage is, if it tilts back then you know you require more weights, if it tilts forward then you know you are OK, and then add a small amount of weights to be certain 

[ckw]

For mine I pretty much filled the radio compartment (there's little scope for adding weight further forward). I added a 'curtain' behind the little window for that compartment so you can't see the weight. There's nothing to look at in there anyway.

 

I think I remember adding a little weight behind the engines as well, just to be safe. I certainly overdid it a bit (been caught out be skimping before!)  Anyway she nose sits quite happily and the gear seems to have had no problem with the extra weight.

 

Cheers

 

Colin

[Giorgio N]

The B-26 is probably one of the trickiest subject when it comes to avoiding a tail sitter: the glass nose of course prevents weight to be put as far ahead as possible while the geometry of the landing gear brings the wheels contact points forward. I never built the Hasegawa kit but when I built the Matchbox one I filled the area between cockpit and bomb bay and also had to put weight right behind the engines. On my kit unfortunately this affected the landing gear legs that broke after a while but Hasegawa's plastic is harder and likely stronger.

SAC offers a metal landing gear set for the Hasegawa kit that includes the cockpit floor and rear bulkhead in metal, so to add weight as far forward as possible. Not a bad idea but the set is not cheap

[Planebuilder62]

@kev67 descibes the simple solution, it woks every time. When I used this method with a B-29 I found I needed a dummy partition was put behind the pilots sears and the volume behind that was filled with fishing weights. Its hard to fix that if the fuselage is glued together.

[TheKinksFan]

I don't understand why manufacturers don't consistently  specify the amount of nose weight that is needed, and what are the best places to put it. Hasegawa's B-24 says 80 grams, but in B-26 there's no mention of nose weight at all. Eduard has in their re-box added 'don't forget the nose wight', better than nothing I guess. These kind of tail sitter should have been designed from be beginning so that there is somewhere place to add the weight, ideally somewhere that is not visibly. If Tamiya or Arma Hobby would release a kit like that (bomber with a nose wheel), I believe they would design it that way. 

 

 

[woody37]

I always take the traditional British engineering route...over design it! There's never too much weight unless the gear can't support it so I usually stick a bolt or nut in. Not what sized nut I used on mine, possibly an M8 or M10, you can see it here at the back of the cockpit painted black and sat in a blob of blutac superglued, the easiest place to add some weight and worked fine.

 

[Graham Boak]

1 hour ago, TheKinksFan said:

These kind of tail sitter should have been designed from be beginning so that there is somewhere place to add the weight, ideally somewhere that is not visibly. 

This competes with the requirement for a more detailed, more accurate, model.  Especially for those with transparent noses.  Sometimes there just isn't any hidden empty space available.

 

But I feel there is simply no need for such weights.  There is no law that a model aircraft has to stand on its nose without other support.  After all, a model ship isn't required to float.  This is just a reflection of a model as a toy, akin to the need to have propellers that can be blown around or moveable control surfaces, wiggleable guns.  You want to do that, fine, but don't demand that manufacturers reduce their standards to satisfy that approach above all others.

[Toryu]

As @ckw mentioned earlier I recommend to put the weight between engine and gear (both sides). There is space for enough weight to hold it down, and the pressure is on the main wheels and not on the flimsy front leg. I did this on my 1/48 Marauder and it worked.

 

C'mon @Graham Boak, it's not toy-like when a model 'sits' right, quite the opposite. I agree, however, that is not the duty of a kit manufacturer to prepare everything so that the modeller has no chance to be creative (be it weight or detail!). A modeller can be distinguished from an assembler by his ingenuity and skills over and above the box contents.

[Graham Boak]

6 hours ago, Toryu said:

C'mon @Graham Boak, it's not toy-like when a model 'sits' right, quite the opposite. I agree, however, that is not the duty of a kit manufacturer to prepare everything so that the modeller has no chance to be creative (be it weight or detail!). A modeller can be distinguished from an assembler by his ingenuity and skills over and above the box contents.

It would be more toy-like if part of the accuracy was sacrificed to make room for weights.  There are a number of ways that sitting on its wheels can be achieved without overstressing the plastic parts.  I suggested one - another less-visible one is to drill holes in the bottom of the wheels and glue rods into the base to take them.  Or just glue the wheels to a base.  A simple transparent rod supporting the bottom of the fuselage will do the job.

[ckw]

I suppose manufacturer's could address the problem by providing alternate metal parts for the nose gear, and if necessary other components of the forward fuselage ... but I'm not sure people would be happy with the increase in price.

 

I think there's always a way to get round the problem. I use the lead tape intended for weighting golf clubs or tennis rackets. This stuff is easy to work and you can fashion your own replacement parts (e.g. nose gear doors or bay interiors) with it.

On 07/10/2023 at 10:28, TheKinksFan said:

Hasegawa's B-24 says 80 grams,

Yes, but unless you have access to depleted uranium, finding space for it is a bit challenging! But having a weight guide is certainly useful as long as people are aware that 'where' is just as important as 'how much'. Testing using methods suggested above is always essential.

 

Cheers

 

Colin

[TheKinksFan]

1 hour ago, ckw said:

I think there's always a way to get round the problem. I use the lead tape intended for weighting golf clubs or tennis rackets. This stuff is easy to work and you can fashion your own replacement parts (e.g. nose gear doors or bay interiors) with it.

I wasn't aware that such tape existed, I'll have to get a roll of that. Are the several thicknesses, or is it standard? I've got some lead sheet and thick lead wire, and Liquid Gravity from Deluxe Materials. The Liquid Gravity is not lead, so it's not so heavy, and it needs a closed compartment and fixed in place with CA glue, so it's not always possible to use it.

It's actually 90 grams that Hasegawa recommends, just checked it. Gold is also heavier than lead, so that could one option 🤔.

[ckw]

41 minutes ago, TheKinksFan said:

I wasn't aware that such tape existed, I'll have to get a roll of that. Are the several thicknesses, or is it standard?

Have a look at https://www.amazon.co.uk/lead-tape/s?k=lead+tape. The stuff I have (can't remember which brand) is self adhesive, which can be handy. But the adhesive is easily removed if you want it plain. Back in the day I had some lead flashing, but these days it doesn't appear to be available (without stealing it off church roofs!).

 

Cheers

 

Colin

[Tbolt]

 

The kit doesn't have the panel on the sidewall of the cockpit ( lower left in photo ) so I made them out of lead, I think I added a little bit in the radio compartment as well.

 

 

 

 

[Chuck1945]

Years ago I got a block of lead wool, small lead pieces of perhaps .4 or.5mm lead wire, at an IPMS show. It was marketed to be used as ballast to add some weight to the rather light model railroad box cars and the like. I only used it once adding a bunch to the forward part of a 1/72 Me 262 engine nacelle. Then I very liberally applied a lot of thin CA to hold it all in place and watched in dismay as the heat from the chemical reaction of the CA curing in a confined space melted the nacelle 😳

[ckw]

3 minutes ago, Chuck1945 said:

Then I very liberally applied a lot of thin CA to hold it all in place and watched in dismay as the heat from the chemical reaction of the CA curing in a confined space melted the nacelle

Been there, done that - and worse ... when a young lad I secured fishing weights into the nose of a 737 with a generous amount of polystyrene cement. Not pretty,

 

As mentioned earlier, I find the adhesive on my preferred golf handle lead tape good enough. If not, PVA does the trick.

 

Cheers

 

Colin

[TheKinksFan]

54 minutes ago, Chuck1945 said:

Then I very liberally applied a lot of thin CA to hold it all in place and watched in dismay as the heat from the chemical reaction of the CA curing in a confined space melted the nacelle 😳

I've read that sometimes a kit can burst open after a long time. Fortunately I read these warnings about not to use CA, probably here on BM. Yesterday I added some lead wire inside the floats of a 1/72 Ar 196. I used  Deluxe Materials Glu 'n' Glaze, some kind of PVA.

[Giorgio N]

My glue of choice for lead weights is silicone sealant, never had any bad reaction and being flexible will not break apart if the model suffers an accident

[Roman Schilhart]

From what I remember, I added about 30g of weight to the forward fuselage and engine nacelles on my 1/72 Hasegawa B-26B:

 

 

 

 

[alt-92]

15 hours ago, TheKinksFan said:

I've read that sometimes a kit can burst open after a long time.

Lead will still oxidise, and during that process it swells up. 

[Tbolt]

4 hours ago, alt-92 said:

Lead will still oxidise, and during that process it swells up. 

 

That's why when I add lead I paint it with enamel paint. It might seem overkill but it should stop any corrosion causing problems.

[tempestfan]

I apologise in advance - I controlled myself since I first saw this thread, but now I can't any longer - you don't add any Wrights to a B-26, only Pratt & Whitneys...

 

Seriously, if the u/c is delicate and may give in to excessive weight, I'd probably take the approach suggested by Graham, with a small pin at the bottom of the nosewheel and a tight hole in the base. Luckily, a delicate u/c was no problem at all with the last nosewheel aircraft I built, the Frog Sea Hawk, so quite a bit of lead went into the compartment in the nose, and possibly also in Frog's "weight space".