G'day Chris here, welcome to Clickspring. In this first video of what will be a
multi-part series, I begin the construction of a John Wilding Large Wheel skeleton clock,
by making the frames.
I'm going to model most of the parts in CAD
as I go along; it should make it easier to follow what I'm doing in each video.
But in this case, it also has the added benefit that I can use a printout of the model
as a template to cut out the basic shape of the frame.
The brass is 3/16 inch engravers brass. And the glue I'm using is an oil based spray.
it holds up quite well to all the handling this part gets while its being made.
I want the frames to be an exact match, so I'm cutting out both of them at the same time, using the one template
And for the time being I'm using these machinist clamps to hold them together.
But ideally I want to do away with these clamps, and hold the plates together
using cap screws at each of the pillar hole locations. You'll see what I mean later.
Before I can deal with that though, I need a way of registering the plates together
so that whenever they are pulled apart they will go back together in exactly the same way.
I'm going to do that with some tapered brass clock pins.
I've decided to put one in the middle of the frame, and the other on the left leg.
That should be far enough apart to give a good solid register,
and resist any twist of the plates while I work on them.
At the very end of the project, I'll plug these holes. All going well, there should be no trace that they were ever there.
The pilot holes were then opened up with a tapered broach to accept the pins.
And the hole was widened until the pins could be inserted deep enough to go through both of the plates.
Once that was the case, then the clamps were removed, the plates separated
and a carbide burr used to lightly countersink the holes on the inner surface.
And then the pins were hammered in.
Now that the register pins are in place, the plates are reattached, the clamps put back on,
and then the 3 pillar holes can be drilled out in preparation for accepting screws.
I can now do away with the toolmakers clamps.
And tap each of the 3 holes in the bottom plate for a 6mm cap screw.
The 3 holes in the top plate are then drilled to give clearance for the same size screw.
The tapping throws up a burr, and I want the plates to sit perfectly flush,
so I deburred the inner side of the tapped holes, and then the plates were reattached
by locating them on the register pins, and then this time holding them together using the cap screws.
So now the waste stock can be cut away, and the plates will still stay tightly registered together through the whole process.
Then I got to work with the scroll saw, cutting away most of the waste stock.
Off camera, I drilled a little hole in this diamond shaped section, to give entry to the scroll saw blade for that inside cut.
Next up I used this little bench filing machine to clean up the cuts from the scroll saw,
and also to clear out the corners...
Then I used a belt sander to bring all of the surfaces closer to the line,
although I left it just a little short for final finishing.
Now you could do all of this without the power tools,
but there's no doubt, they make the job a lot easier, and they save a lot of time.
The circular sections at the pillar holes need to be spot on, so I've turned up this little filing guide from mild steel
to limit the cut, and I'm finishing up those areas with a fine cut file on the filing machine.
And then from here it was all hand finishing at the bench vise.
using files to get the curves nice and smooth and symmetrical,
and to clear out and square up the corners.
That was followed by papering of the edges.
First with 400 grit,
and then 800 grit, to leave a nice surface finish.
I'm finished with the paper template, so that can be removed with a little white spirits.
I wont be doing any polishing of the frames at this point, I'll do that right at the end when the clock is almost complete.
And then briefly, it's back to the mill, to drill out the 3 pillar holes,
and then ream them 1/4 inch to accept the pillars later.
Now that all of the metal has been cleared away, here's a better view of how the register pins work
I'll need to be able to bring the plates back together like this several times down the track, for drilling pivot holes.
And that's the frames complete. In the next few videos, I'll make the pillars, washers and screws.
Thanks for watching, I'll see you later.