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1to1scale

I must be crazy, B-24J on the bench.

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Hubert you need to give it to me in layman's terms.  I did read your other posts and I'm sure they're full of awesome information but to me they may as well be written in Sanskrit.  Is there anyway you can break it down for a dummy like me :-) :-)

 

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To make a long story short : the wing in the kit has almost the right thickness  (should be 22% of the chord - the chord is the « depth » of the wing from front to rear - i.e., at the root - where the wing meets the fuselage - so that is 22% of 133.35 mm = 29.4 mm ) but the kit’s wing profile is too symmetrical between the top and the bottom wing. The original Davis airfoil was more rounded on the top wing and flatter on the bottom wing.

Plus, a key feature of a wing on any aircraft is the incidence. The incidence is the angle between the aircraft’s datum line (the « mid » line of the fuselage when the aircraft is flying horizontally, and the line that goes from the middle of the leading edge curve to the trailing edge. On the picture I inserted, this line is shown clearly. Any wing is set at a certain incidence, which contributes to the lift - and drag - generated by the wing. On the B-24, this incidence angle is 3.26°, which makes the trailing edge be positioned lower than the middle point of the leading edge. The impact is that the bottom wing seems to be almost flat, when the top of the wing seems to slope sharply from the point of maximum thickness to the trailing edge.

On the kit, the wing seems set at less than 1° incidence, which makes it appear too « flat ». Thus the trailing edge is too high relative to the top of the fuselage. With the wrong profile, this contributes to spoil to appearance of the wing. 

Check Iain’s pics on LSP. They show the overlay between the kit’s wing and the correct Davis airfoil, positioned at the correct incidence, and the corrections Iain is attempting to modify both the profile and the incidence.

HTH

Hubert

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Last night I tore apart some of the built and detailed bulkheads, I scraped off and sanded down all the styrene strips on the three middle bulkheads and re-engineered them to better reflect the real aircraft. The aft bulkhead between the wing and ball turret got the proper cutout, the navigator room rear wall got a proper floor hatch, and the forward wall got cut out also. I plan to add the needed bracing and the correct "plywood" squares behind the pilot. Ill post pictures later if I can.

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34 minutes ago, 1to1scale said:

Last night I tore apart some of the built and detailed bulkheads, I scraped off and sanded down all the styrene strips on the three middle bulkheads and re-engineered them to better reflect the real aircraft. The aft bulkhead between the wing and ball turret got the proper cutout, the navigator room rear wall got a proper floor hatch, and the forward wall got cut out also. I plan to add the needed bracing and the correct "plywood" squares behind the pilot. Ill post pictures later if I can.

You'll be pleased to know that a certain individual who has just released a beautiful Lancaster IP is working right now with my kit parts to make a much improved cockpit. I've seen initial models of the IP and it looks stunning!! The kit part is so flat and featureless.

Please tell us what is wrong with the cockpit rear bulkhead, part M2 before he goes any further.

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On 12/31/2018 at 5:52 PM, Dennis7423 said:

Is it just me, or are the seats really, really far from the rudder pedals and control wheels?

 

- Dennis S.

  Thornton, CO USA

Dya know i thought exactly the same thing. The 1/32 B-17 is the same. 

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On 12/30/2018 at 3:06 PM, smitty44 said:

Bring it, Peter! It needs some Airscale love!

Your prayers have been answered Smitty. The Love is being spread all over it right now!!

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Hey all

 Just a thought on my part. The engines in the B-24's were P&W R-1830 dual 7 cylinder radials.

 The ones in the kit are a pretty poor representation of them. You can get resin replacements for them, but they are expensive. I found out that the B-24, DC3 and the Grumman Wildcat all had the same engines. So I went on the internet and found on Ebay the engine sprue for Trumpeters 1/32 Wildcat kit for I belive $17.00 bucks. It's fairly well detailed, the only thing that needs to change from the Wildcat to the Liberator engine is the front gear case, it has twin magnetos and the engines in the Lib only had a prop pitch regulator on the top of the gear case. The magnetos were on the rear of the engine. Its a simple fix, snip, snip some filling and sanding and adding the prop regulator. 

 I'm working on it know when I get to a point I'll show pictures of what I'm talking about. You can Google the R-1830 and see the photos. And Wikipedia will show the P&W R-1830 and show which planes had them.

Ron G.

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Hey all

  Some more info 

20190105_141111.jpg

This is a P&W R-1830 radial engine

 

20190105_141514.jpg

That is the prop pitch regulator.

You can get Vector resin R-1830's for around $30.00 bucks that works out to $120.00 for (4) of em.

I ordered 4 of these from a place on scale mates. They are the old Williams brothers 1/32 double wasps. Not very detailed but way better the what came in the Hobbyboss B-24.

 

966802-13741-25-pristine.jpg

I'll let you all know what there like when I get them in them mail. I have a 1/8 scale Williams brothers R-985 radial kit its pretty detailed even has plug wires and spark plugs. It's baried in my stash, but if I can find it I'll post some pictures.

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I almost forgot the brass barrels from Master for the HK B-17G will work for the Hobbyboss B-24 kit. I'm waiting for mine to show up in the mail. Also Squadron has resin wheels for the B-24 also the resin wheels that Eduard makes for the HK B-17 will work on the B-24. They used the same size tires and wheels you would still have to come up with the frt. tire or use the kit one.

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I thought Williams « Twin Wasps » were actually R-1535 « Twin Wasp Jr » rather than R-1830 Twin Wasp, but I may be wrong on this one. 

The only noticeable difference in this scale is the diameter (1121 mm vs 1220 mm in 1/1, so roughly 3mm in 1/32) which is actually not so much on the cylinders (the 1/16 of an inch difference in bore and stroke is equal to 0.05 mm in 1/32) as on the crankcase diameter.

Anyway, great idea to go for these « venerable » Wiliams engines.

Hubert

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The TSC4-G (R-1830-41)  was 4' 0.0625" Dia. X 5' 3.48" lg. It was turbocharged simaliar to the B-17 engines. All of P&W twin row engines were called twin wasps. I'll check the measurements on the WB engines once I receive them in the mail. I still have to check the R-1830 I have from the Trumpeter F4F-3 to see how it measures up.

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I'm back 

 So here is the engine from the Trumpeter F4F it's not bad, but needs work to make it into a B-24 engine.

First here are som pics of the sprue.

20190106_133036.thumb.jpg.6ff1108297ee2b6b815e4ff64f47a574.jpg20190106_133012.thumb.jpg.fddab8594121d89cf6da352166f46901.jpg

20190106_133026.jpg

20190106_133030.jpg

20190106_133033.jpg

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I'm back 

 So here is the engine from the Trumpeter F4F it's not bad, but needs work to make it into a B-24 engine.

First here are som pics of the sprue.

20190106_133036.thumb.jpg.6ff1108297ee2b6b815e4ff64f47a574.jpg20190106_133012.thumb.jpg.fddab8594121d89cf6da352166f46901.jpg

Here is what needs to be fixed.

 

20190106_141032.jpg

Part before modifying.

20190106_141337.jpg

What needs to be modified. Snip those off then add the prop pitch regulator. Engine still needs to have the valve rocker covers with oil return lines added (they are on the sprue), exhaust pipes, rear cover & plug wires (need to drill holes in the cylinders for them), etc. Some simple scratch building and one nice engine to have open for maintenance in a diorama.

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I'm back 

 So here is the engine from the Trumpeter F4F it's not bad, but needs work to make it into a B-24 engine.

First here are som pics of the sprue.

20190106_133036.thumb.jpg.6ff1108297ee2b6b815e4ff64f47a574.jpg20190106_133012.thumb.jpg.fddab8594121d89cf6da352166f46901.jpg

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So I  just measured the engine diameter of the kit engine and it scales out to 43.232" (1,098.092 8mm)  the actual P&W R-1830 should measure 48.062.5' (1,220.7875mm) which leaves a difference of 4.8350" (122 809mm) thats 2.4175" (61.4025mm) off in radius in 1/32 scale thats 1.92mm!!! Ouch!

 The Trumpeter F4F P&W R-1830 (shown in the post above) will not fit in the cowling of the Hobbyboss B-24J :(:hsmack::omg:

The Trumpeter F4F P&W R-1830 scales out correctly its 48.0625" in dia. Guess we're stuck using the crapy kit engines.

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17 minutes ago, CrankyCrafstman said:

So I  just measured the engine diameter of the kit engine and it scales out to 43.232" (1,098.092 8mm)  the actual P&W R-1830 should measure 48.062.5' (1,220.7875mm) which leaves a difference of 4.8350" (122 809mm) thats 2.4175" (61.4025mm) off in radius in 1/32 scale thats 1.92mm!!! Ouch!

 The Trumpeter F4F P&W R-1830 (shown in the post above) will not fit in the cowling of the Hobbyboss B-24J :(:hsmack::omg:

The Trumpeter F4F P&W R-1830 scales out correctly its 48.0625" in dia. Guess we're stuck using the crapy kit engines.

The next question is: are the cowlings’ outside dimensions accurate, or are they too small as well ?

Hubert

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13 minutes ago, HubertB said:

The next question is: are the cowlings’ outside dimensions accurate, or are they too small as well ?

Hubert

Hey I'm back 

 So here is the engine from the Trumpeter F4F it's not bad, but needs work to make it into a B-24 engine.

First here are som pics of the sprue.

20190106_133036.thumb.jpg.6ff1108297ee2b6b815e4ff64f47a574.jpg20190106_133012.thumb.jpg.fddab8594121d89cf6da352166f46901.jpg

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Hey hubert

 It's probably to small which means the nacelles are to small also. :wtf::(

 

20190106_160800.jpg

Here is a picture of the kit cowling and a P&W r-2800-21 thats in my Trumpy P-47 Razorback you can see the lack of detail. I think with a little bit of detail it might look passable, maybe.

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You know what I’m thinking?

I think we’re blowing up a good man’s build thread with tweak talk.

We should maybe start a thread for that up in LSM discussion.....

Edit: started one up top in modeling discussion

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Good idea cupcake !......harv

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23 minutes ago, Clunkmeister said:

You know what I’m thinking?

I think we’re blowing up a good man’s build thread with tweak talk.

We should maybe start a thread for that up in LSM discussion.....

Very good point, Ernie. I am probably among the first to be guilty as charged of feeding this thread’s creep ...

Hubert

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3 hours ago, HubertB said:

The next question is: are the cowlings’ outside dimensions accurate, or are they too small as well ?

Hubert

Hey I'm back 

 So here is the engine from the Trumpeter F4F it's not bad, but needs work to make it into a B-24 engine.

First here are som pics of the sprue.

20190106_133036.thumb.jpg.6ff1108297ee2b6b815e4ff64f47a574.jpg20190106_133012.thumb.jpg.fddab8594121d89cf6da352166f46901.jpg

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Completely agree Ernie as a separate thread would be perfect to keep all the engine information in one place and not take away from a wonderful build thread.

Peter 

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54 minutes ago, Peterpools said:

Completely agree Ernie as a separate thread would be perfect to keep all the engine information in one place and not take away from a wonderful build thread.

Peter 

+1

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