FN5 Turret dimensions?

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4 years 5 months

Posts: 44

Would anyone here be able to provide me the approx height measurement, shown in pic, of the FN5 from top of rotating ring to the cupola seal on the rotating service joint?

Also the inner and outer ring diameters please? It was discussed here http://forum.keypublishing.com/showthread.php?138114-Turret-Rings&p=2299175&highlight=FN5+diameter#post2299175 but there seemed to be a few differences, or if someone can confirm the same size rings were used on the FN11/16 and FN5 turrets

Any help or reference material would be much appreciated.

Cheers

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Member for

9 years 8 months

Posts: 411

Here are a couple of pics that might be of help.

These courtesy of The Stirling Aircraft Projects FN4.

James

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9 years 8 months

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You don't say what you want the dimensions for - I have many dimensions both measured from the turret and interpreted from the AP - giving rise to this model:

https://www.youtube.com/watch?v=cmu_Ww1HiPw

Also the Turrets AP 1659A is good reference but you seem to have the pic from that already.

Sadly I also had trouble deciding what the diameter actually was, the AP states "Diameter of Ring 34.5" - but is that inside - outside? What ring?

James

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11 years 8 months

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Surely the key parameter for the turret ring diameter is the circular hole that it sits in? Sorry if that's too simple-minded for the compliers of the AP or perhaps even the turret designers?

Profile picture for user 12jaguar

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13 years 3 months

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I think you meant FN5 James :)

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9 years 8 months

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I think you meant FN5 James :)

Can I claim 'speling mistake'? :apologetic:

James

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13 years 3 months

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Can I claim 'speling mistake'? :apologetic:

James

Absolutely :)

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6 years 9 months

Posts: 40

The internal diameter of the turret ring is 34 .2 inch ,from the bottom of the arch that carries the rotating service joint to the underside of the joint equals 25 7/8 inch plus 2 3/4 inch will take you to the point that you require.
I will post the actual size and thickness of the turret inner ring within the next couple of days..............I hope this is of some help?

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Please be aware that the source drawing you have is NOT to scale, and contains many geometry errors. I know this as I had correct numerous errors on my drawings for model turrets. Unfortunately I am unable to answer your specific question accurately, as I changed the upper rotating-joint. I'll see if I can get you an approximation in the coming days.

I've almost finished scratch-building a pair of FN5's to 1:4.5 scale, and am in the process of simplifying the build to build turrets for the RC community, as the current turrets take around 2 years to build. They feature a fully working collimating gunsight with reticule and autodimmer, mechanical linkage of the sight to the elevation of the gun-cradle, and numerous lamps, also doors with working latches, and pneumatically operated gun elevation with (eventual) servo operated traverse. The intention is to mount cameras in the turrets in flight.

I did have to make a few changes to the turret, particularly the fixed/traversing ring, and the rotating joint at the top. Otherwise, they're as accurate as I could make them given the almost complete absence of surviving technical drawings. If you search YouTube for Fidd88 you'll find my channel documenting the builds over time and the "triumphs and disasters" during that period.

https://www.youtube.com/watch?v=fry_xO3JGTo for one film

Pic of the FN5 internals

 

 

If I can be of help with FN5 stuff let me know..

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Profile picture for user Fidd88

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That turret was designed and built by Helimadken, and was in fact the inspiration for mine. Quite amazing work in 1:10 scale.

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Hi Fid88

That's right, he used my 3D model to print the parts. While the software I use is mainly for graphics, all of the animation maths is done by the software such that any size model should operate correctly. I do have  some models on here under jamesinnewcastl, sadly my old name victim of the 'new' improved web site!

 

James

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16 years 8 months

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Coincidentally I've just measured the Stirling project FN5 turret last week. 

The fixed part of the ring that attaches to the airframe gas an external diameter of 38.25".

I can confirm that the inner diameter of the moving part is 34.5".

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6 years 9 months

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Has any body got a spare FN5 turret ring kicking about ?

Profile picture for user 12jaguar

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13 years 3 months

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got an FN4 but different diameter

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6 years 9 months

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Hi 12Jaguar  I could very well be interested  in the FN4 turret ring as I have the remains of a FN82 rear turret which is missing its rotation ring , the accommodation base and the cupola  and it would not surprise me if the FN4 ring is the same size .

If possible could you send a PM , many thanks 

Profile picture for user atbl12

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I would like to thank everyone who has taken the time to investigate and respond to my original post as it appears I haven't till now, much appreciated.

 

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6 years 9 months

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Hi atb/72   I think I have sent you a pm but not really sure ?

Profile picture for user 12jaguar

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13 years 3 months

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Hi Ball Turret

have sent you a PM

John

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1 year 6 months

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Jamesinnewcastle, I've pm'd you, which you may have missed....