OK guys, I've been a busy bee the last two days, my friend "dropped round with his lathe"!
So off we jolly well go!
I had nothing much in the way of aluminium stock, so it had to be done with what I had, a few bits of aluminium tube and a LED torch, the body of which made some the ball race mounts.
The bearings were of two sizes: 1 ball race OD. 30mm X 17mm ID X 7mm thickness
3 ball races OD 27mmX 20mmX 4mm thickness
1 axial needle roller race 45mm ODX20mm ID thickness 2mm.
... these three 27mm OD races still allow a 20mm ID ....this is the key to fitting it all in the limited dimensioned housings of the Beike gimbal head. The bearings came from ebay (eventually) and were for next to nothing, less than 10 euros.
The interior diameter of the two bearing emplacements in the rotational horizontal pivot were 26mm and the first job was to Dremmell the lodgement out to 27mm. A spacer was made so the two ball races to prevent the bearings closing together and under all that went the axial bearing.
The upper swinging arm axe (shaft) is easily unscrewed from the hanging "arca swiss" support with two allen screws hidden under a cover disc and then the shaft (axe) could be put in lathe chuck and turned down to 20mm with the tail diameter of 17mm, a reduced diameter section of the shaft was needed for the brake. The 30mm larger bearing just slotted in nicely into the original placement and all that was needed was a couple of spacers made from my donor torch.
Sparing you guys from to many constructional details, what was the final result?.....
Well, the pendulum axe rotates sweetly, the large knob provides a smooth brake via a rubber disc while the upper wing nut (pinched from it's arca swiss plate) locks it tight. The rubber used is just a bit of cycle inner tube...temporary. Rotational operation is smooth and sweet and locks with it's original small knob at the base.
The Beike gimball head (pendulum type) is a borrowed design substituting decent ball races with plastic bushes and spacers, the resulting operation is usable but not ideal, given the price of the Chinese bearings I used I find it strange that they didn't opt for this sort of construction. Most of the work was just changing shaft diameters and would have cost little more in terms of time and effort.
Lastly just to convince us that Beike isn't vying for Really right stuff customers, it offers a spirit level mounted vertically in the tightening knob on the end of the arca swiiss plate.......serving us nothing but as an amusing conversational point.
In the place of where the spirit level should have gone (on top of the rotational housing) they fit the smallest and most useless compass that ever fell out of a Christmas cracker..... Oh deary me!
With some gimbals costing anything up to €500, anyone who has one of these Beike gimball mounts (and they have sold many many thousands) and has a "penchant" for a little lathe work would do well spending a little time on a rainy day modding theirs, the net result is quite a decent unit!