WIP - Marble Tower

[InsideBevel]

Thanks for posting this
I suddenly remembered that I bought the same plans a couple of years ago, but never got around to build it.
This might be a good opportunity to get started...

 

[Ian down london way]

Left side done

This section sees the left path, from splitter to starting point, complete.

There weren't too many challenges to solve, although the aesthetics took a while to get 'right'.

After the switch back and bells, the marble is routed into a bowl, where it orbits for a while, before dropping through a hole in the bottom. It then is supposed to roll underneath a series of free hanging clowns before being re-directed to the starting point.

I'm using some spalded (?) beach that a friend gave me. its it bit past it, and I don't think it would make a good bowl without a great deal of super glue to hold it together - so this use is pretty good.

The inside is shallow to keep the marble rolling, so the sides are rather thick, but hey ho, why not.

A little burnt decoration and mounting it within some grippers, gives me this.

The clowns weren't difficult to make, but it turned out that the marble, on the slope dictated by the design, wasn't enough to get beneath the clowns - which kind of defeated their purpose.

In the end, I was able to solve that buy sanding off the heels of the clown (thinning down their legs), which both made them less bottom heavy, and also altered the height that the clown had to be lifted, and the angles involved. So the marbles seem to work well now. the supports for the clowns was shown in the plans as being a 2 inch nail, but I had some 1/16th steel wire left over from the last project, so I used that and put some decorative caps over the ends, to restrain the wire and for aesthetics.

Here is what they look like, after I've also added some 3/8 inch dowel, sanded almost flat, for buttons.

To route from the bowl to the clowns, a shoot is mounted off the back rail. To jump the marble sideways, I tried inserting a triangular section, but it turned out it just needs to bounce across, so I ended up with a minimalist thin dowel in the corner.

Once the marble gets to the bottom, there is just a small two-section shoot, to fit. there isn't much of a drop, and getting all the angles right (and indeed the connection between the shoots) was a little fiddly, but not too exceptional. I had to cut out a notch from the side of the starting dish and also sand off the bottom of the trough section, to create enough of a drop, but it all seems to work reliably.

So, that's the left hand route done ! yea !

 

[Ian down london way]

Now down the right hand side.

This has three parts. The first is a spiral racetrack, the second is a xylophone and the third is a zigzag course, with a bell at the top.
I think its not as hard as the left side, so I won't post quite so many pictures.

So, first, the spiral racetrack.

The marble from the top splitter is routed down a chute into a spiral. This is made from a thick sandwich of play wood, that is stretched vertically, by pressing it down onto a stepped shape.

Here is how it looks from behind, and the sideways view, where you can see how the opposite sides slant in opposite directions.
Quite easy to make, as long as you only progressively stretch down the ply. I screwed each level down first with steel then with brass screwes, and let the wood relax for a while between each layer, before stretching it to the next level.

The marbles drop out of a hole at the back, and have to be redirected onto the xylophone.

This was a cheap kids one, bought on ebay (from China probably - quite how this is done, I don't understand).
So, a simple one, metal strips, on a plastic base. The notes are good, but helped by the fact that there is a thin rubber band around the support pegs, which keep the metal off the plastic, so they can 'ring' properly.

I tried a number of ways of mounting the strips. The first attempt was a block of wood, and using cut off screws to create metal polls onto which the sounding strips are restrained, and reusing the rubber band to keep the metal in the air.

Trouble was, the marble ran down it way too quickly, and didn't really make a noise.

So I decided it would be better as a series of steps.

Tricky to make something to hold the sounding bars, the screws didn't work well. I didn't have dowels small enough. In the end I managed to get tooth picks to work !

I've used long toothpicks at top and bottom, and stuck them into a thin 'beam' that acts as a side guide for the marble. This is a push fit into the top and bottom holes. For all the others, I've stuck the toothpick into the step, so the metal bars just sit in place.

At the top, there is a redirection block, so the marbles, when they exit the race, run down the xylophone. Turned out I needed to stop the marbles jumping sideways, so a couple of extenders at the top help.

Nearly there for today.

Some additional guides at the bottom, and a catcher which redirects the marble backwards (its on a screw, so pivots when the weight of the marble lands on it) and its onto the next part.

That's all for now.
Hopefully finish within a month, and a link to a youtube video in the last posting.

 

[nathandavies]

looking forward to the video of this.

 

[Ian down london way]

This should be the last posting for this WIP apart from adding a link to a youtube video, once I've made that.

So, the last bit is a zig-zag return which is the equivalent place to the clowns on the left side. Same slope, and it will drop the marbles into the start tray in the same way.

This time, I decided to create the bit with two contrasting layers of wood (where as I usually cut out the shape and re-glue it back in, to match the grain - like the snake-y part near the top left I described much earlier). So, simpler to make, just 'hengner'ed the top bit (is that a verb?) from some beach, and stuck that onto some left over iroko (anyone want my left over iroko, working it does not do me any good, the dust gets to me).

The end of the zigzag has a mounted bell. The aim is to shoot the marble onto it, and it then bounces into the zig zag catchment section at the end.

Again, i wanted to mount the bell fairly accurately, in the middle of its support, and at a particular height. The plans use a rod, with a notch in the middle, to try to keep the bell centered, but I couldn't get that to work well. So, I used the same technique as I had used to mount the small bells - fishing line through a hole in a screw at the top. Here are the parts:

It was quite tricky to attach the top part to the legs - there is no real gluing area, plus its end grain, of course. In the end, I used mini-dowels, called toothpicks Had that not worked, I was prepared to use brass / steel wire (1/16th inch), but the toothpicks seems ok, they aren't carrying any wight. They are glued into the legs and the cross member.

I wanted to be able to have the bell support removable, so I decided to mount it on begs at the bottom too.

I tried toothpegs again, and accidentally (!!) glued them in place at the bottom. I was going to shift to metal for those supports (which need to be stronger than at the top), but they actually seem ok.

You can see them from this side view.

I'm very pleased with how it looks, with the contrasting colours.

Like the clowns, I wanted this to be removable, so a couple of dowels glued into the support should do the job. 6mm dowels in this case. It turned out to be tricky to get the drill in, so I had to disassemble the layer above to create the space to work. Fortunately the supports are screwed in place, so they can all be removed.

So, now to connect the exit of the xylophone to the bell, using a channel. However, after some use, it turned out that sometimes the marbles jumped out of the catcher at the bottom of the xylophone. So I had to add a stopper, to make sure the marble dropped vertically onto the catcher.

(breaking the post here, so I can add some more pictures)

 

[Ian down london way]

last few bits

Now the zig zag is mounted, I can fit the chute to direct the marble at the bell.

The chute is cut using a rounded router bit, with the table mounted router, so that the strip of square wood can be slowly cut as the bit is raised a mm at a time. Its mounted by hanging it down from the horizontal supports, on two bars.

Then its just a question of mass-hole plugging. There are 24 large screws which now need to be plugged (supporting all the various cross members).

I cut 10mm plugs using plug cutters from beech, and try to match the gain and direction to make them look decent - I don't need them to disappear, just to look nice.

I had recently bought a Worx tool, which I see you can now buy at B&Q, but I bought it from the web. This is Argos selling it: http://www.argos.co.uk/static/Product/p ... 112472.htm.
I bought this on a bit of a whim but its proven really good at a number of jobs (especially chopping out the bottom of door architrave to fit laminate flooring which disappear under the architrave - wonderful.
Its also good at cutting off plugs, and then sanding them down )

A few more smaller ones at the top (4) and a couple low down - so 30 plugs in all.

At this point, having moved it around a bit, I found some decorative parts I'd forgotten to fit. I guess it's the the equivalent of a car mechanic's pocket screws

And that is it - Done !!!

its rather tricky to see it all, but I'll try to construct a decent video this weekend and edit this posting to put the link in at the bottom. However here are the four face views:

And here is the video on you tube (link to be added later).

 

[riclepp]

Really nice work Ian, I bet it is a pleasure to watch it work. Thank you for a most interesting WIP

 

[InsideBevel]

Great posts =D>
Looking forward to the video....

 

[Spindle]

Hi

Loved the WIP - looking forward to the video.

Must have been a very satisfying build =D> =D>

Regards Mick