Thoughts on a ball bearing turret mount

[AlwynTurner]

Whilst sitting on my Sun lounger contemplating my next beer I have been turning over how I could 3d print a ball bearing mount for a turret (this is because I am a sad git experiencing withdrawal symptoms for my beloved/hated 3d printer). I have a rough design in my head but need to get info from experienced rc tankers 're turret mount hole sizes. I know there is a standard heng long 360 degree turret ring, does this mean that all hl tanks have the same size upper hull hole for the turret or are they all different? I have a KV1 upper hull I can practice on when I get home to test the design but it would be good to know whether I could build a one-size-fits-all solution. Any feedback would be great, I recall someone commenting at some time about the lack of a bb turret mount.
Alwyn

[silversurfer1947]

It won't help you one little bit, but my Puma turret
really could do with a ball bearing mount. I doubt it matches anything else, but if it is of any use, I can easily measure it.

[AlwynTurner]

Hi Richard, that would be great, also it would be good to have pics of the hull minus turret from above and below and the turret from below. I would like to do one or two test cases so no cost while we experiment. There is no rush as I am only back on 2nd july.
Best regards
Alwyn

[jarndice]

Hallo Alwyn,
I bought two Metal Ball Bearing turret Rings for Heng Long/Taigen Tanks from http://www.rctank.de a few months ago one is for a PZ4 the other is for a Tiger1,
These are labelled SMALL VERSION.
Both are 51mm across but they are not one size fits all as they are available in another size which I don't have.
Shaun.

[AlwynTurner]

Thanks Shaun, I see from their design they are using 3 small bearings equidistant around the rim. I had in mind a proper bearing the size of the turret hole with 3mm balls in a cage with upper and lower plates. It should be straightforward to design and print, the balls are readily available, I just need to get the sizes right.
Alwyn

[jarndice]

My golly, that sounds like real engineering when I left school I was apprenticed to an old school Garage where the practice was to repair rather than just replace failed mechanical parts,
I would too often be given the job of reaming various auto parts to locate a new bearing,
The size you are contemplating is going to be quite heavy assuming the race will be steel,
What will you be mounting it in? Nylon, Plastic, Carbon, Metal?
Shaun.

[AlwynTurner]

I'm hoping to get by with about a dozen balls with abs printed upper and lower plates and ball cage. It may prove not to be durable but I plan on giving it a try, it must be better than plastic on plastic contact as is currently the case. It will be an interesting experiment anyway and it's giving my brain some exercise whilst consuming sangria.
Alwyn

[silversurfer1947]

I'll get it done. Just need some new batteries for my Vernier calipers.

[AlwynTurner]

The design I have in mind is a lower race with a groove for the balls which will attach to the hull, a ball cage for the balls to sit in, and an upper race with a corresponding groove for the balls, which will attach to the turret with the turret drive rack acting to hold the upper and lower races together by means of screws into the turret. It will all make sense when I put it into openscad (I hope!)
Alwyn

[43rdRecceReg]

Whilst sitting on my Sun lounger contemplating my next beer I have been turning over how I could 3d print a ball bearing mount for a turret (this is because I am a sad git experiencing withdrawal symptoms for my beloved/hated 3d printer). I have a rough design in my head but need to get info from experienced rc tankers 're turret mount hole sizes. I know there is a standard heng long 360 degree turret ring, does this mean that all hl tanks have the same size upper hull hole for the turret or are they all different? I have a KV1 upper hull I can practice on when I get home to test the design but it would be good to know whether I could build a one-size-fits-all solution. Any feedback would be great, I recall someone commenting at some time about the lack of a bb turret mount.
Alwyn

Hi, Alwyn..and if you're not now horizontal after several beers this question is one I looked into for my Cromwell project. Apparently, virtually all HL/Taigen tanks have the same size turret ring and aperture. The latter comes in roughly at 90mm in diameter, and the ring itself 102mm diameter from tooth land to tooth land (and no, that's not a fairytale territory inhabited by Dentists ).
The 360 deg kit from Taigen hints at this:
"...TAG120625 - 360 Degree Airsoft Rotation Kit

For airsoft tanks without turret machine guns.
Fits: Tiger 1, M41, M26, Panther A, Panzer III, Panzer IV, KV-1, King Tiger (Henschel), Panther G (Plastic), & KV-2 tanks.
Plug and Play!
*Note: King Tiger (Porsche Turret) not supported*.."
On RC tank, these models are listed as 'Small'. The two exceptions appear to be: the Abrams M1A2 and the KT Porsche version. They're listed as 'Large". The Cromwell takes the 'small' version, like most other models.

Roy. Cheers,and Slainte!!