If you missed part 12, please find it here.
The Dominion turntable is coming along nicely but I need some way of making it turn (to put the turn in turntable 🙂 ). I decided to make a Lazy Susan in wood to be the base of the Dominion turntable.
Basically it’s a big ball bearing made from wood and with marbles used as balls. It looks like this:
I milled a circle with outer diameter 250 mm and inner diameter 230 mm and a groove for the marbles. Then I milled a ring with eight holes to hold the marbles evenly distributed and a lid with another groove. Putting it all together it looks like this:
Finished Lazy Susan
Just to test how it will look in the end, I put one half of the Dominion turntable on top:
Dominion turntable test
Now, all that is missing is a lot of sanding and then assembling the whole thing. 🙂
When milling the Dominion turntable I noticed that my ShapeOko 2 wasn’t square – or to be more accurate: I noticed that the cutter took about 1 mm more of the surface in one side than it did in the other side.
At first I just thought that the lumber didn’t have the same thickness in both sides but when I milled the second part I noticed that the difference was consistent, so I made the conclusion, that my ShapeOko 2 wasn’t square.
After some considerations I came up with the following idea: I bought a digital dial indicator and constructed a holder so it could be mounted in the bracket for my spindle. It looks like this:
Digital dial indicator
The holder consists of two parts: a square to be attached to the dial indicator and a round piece with diameter 43 mm that fits the bracket for my spindle.
I then mounted the thing in my ShapeOko 2 and started to measure it’s height above the surface. Sure, there was a difference from one side to the other of about 1 mm.
I then adjusted the frame by lifting or lowering each corner by loosening the screws and move the y-rails before tightening the screws again. After some fiddling (read: a lot) I finally ended up with the following measurements for the four corners.
Left front corner
Left background corner
Right front corner
Right background corner
With a difference of only 0.04 mm I’m very pleased with the result. 🙂
If you missed part 11, please find it here.
So far so good
I’ve finished milling the top of the turntable without anymore unwanted visits from my old pal Murphy. 🙂
The two half circles looks like this:
The two half circles of the Dominion turntable top
Now, a lot of sanding is needed and the two halves needs to be glued together. 🙂
If you missed part 10, please find it here.
This is just an update to let you know that my “friend” Murphy is very much alive and kicking in 2015!
Anything that can go wrong, will go wrong – and at the worst possible moment.
It’s true! I was just about to finish milling the last quarter of the Dominion turntable when disaster struck: During the last run in the y-direction with the ball nosed cutter, my ShapeOko 2 suddenly decided to shift everything about 10 millimeters in the y-direction with the following result:
Murphy’s law at work
Murphy’s law at work – a closer look
Now I have to start milling these two quarters all over again… 🙁