Hi all,

I’ve now completed – after 5 years – both turrets, and have made a short film on youtube – just over 15 minutes – which provides a “cook’s tour” of them, with much footage and stills and narration from both inside the cupolas, and looking in. If you’re interested, and enjoy the film please leave the usual comments/likes on youtube and/or here.

Cheers, Fidd88

https://www.youtube.com/watch?v=i3bkapxHp5M – latest film. Also check out the films “moving rams” and “new mkIII gunsight”

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

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

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

And a further film of the turret elevation and depression now being powered via compressed air delivered, for now, via a pair of syringes. The results are fairly pleasing, as the method of raising and lowering the gun-cradle without visible or audible servos has been a major headache for some 2 years.

Today I painted the 160 or so clips which will in time bolt the curved Perspex window panels to the internal stanchions and bars of the cupola, as per the original. I’ve also been assembling the various hydraulic lines, made from 3d printed curved pipes, and brass tube of equal diameter for the straight sections. Painting and fitting same should commence in a day or two. When complete the only thing left to do is to make the mould from a plug, to cast a positive, over which the hot Perspex can be drawn to fabricate the complex curvatures of the windows.

Hi All, it’s been many months since I last posted, and much progress had been made lately, chiefly on the cupolas for the FN5’s, but also a pair of new and much improved MK III reflector gunsights, and the turret-doors (which feature working internal and external latches, bolts, and concealed screw to prevent doors opening in flight.

Finally I think I’ve slain the problem of the elevation rams for the gun-cradle having, as the army says “used all available cover” to get there! I built an electric ram which worked, rather gratifyingly, but hadn’t enough power to move the cradle from the fully elevated position. Hydraulics were considered next, but were rapidly discounted owing to the spectre of a leak within the model turret. Pneumatics was about the only possible solution if the original design brief of “no visible servos or arms thereof”, was to be addressed. So I’ve now 4 rams on the way with the added benefits that each pair of rams will exert the same force at the same time – which I couldn’t achieve with the electric rams.

Next week the final acid-etched brass parts should arrive, which after fitting should allow the final work on the turrets to begin, namely wiring services to looms, making the foam plug from which an eventual mould can be made to generate the complex-curved Perspex “window panels” in the cupola before finally some bloody fiddly work bolting the cupola structure and windows together. Then the air-frame work begins!

I post a couple of screenshots, and refer you to my you-tube channel – searching YT for “Fidd88” without quotes will find me. Films covering lots of aspects of the builds are there if anyone is interested.

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This is an old shot of the “pipper”. Since then the 3d-printing layers on the arms have been got rid of, and painted; and the angled glass is now optically clear. Damn silly, but enormous fun to make. If it’s appropriate here, and people want to see more, I’ll post some more pictures.The whole unit from bottom of box to top of the shroud is just under 35mm,