Woodworking in the great white north.

Posts tagged “marble tower

Marble Tower – for charity?

The marble tower is done and making a home inside the house (sadly no more playing in the workshop, back to work). 

A few years ago I came across a marble tower that was bigger than the one I made, but conspicuously similar in design.  It was in a restaurant and had a gumball dispenser on top that was presumably for charity purposes. 

Coincidentally, I came across the very same thing a couple of weeks ago, although the sides are encased in some sort of plexiglass type material to protect it from the public.  The money collected was to go to a local hospital and if you got a black gumball, you won a prize.  My daughter gave it a try.  The gumball wound its way around the various ramps and mechanisms (making far less sound) and ultimately depositing the gumball in a receptacle at the bottom.

What do you know, my daughter got the black gumball and won admission to the pumpkin-land they will set up this fall.  Cool!

I snapped a couple of blurry pictures (sorry) as you’ll see below.  It appears that an entrepreneur has worked out a CNC method for producing the parts for these marble towers and produces them as needed for charity gumball dispensing. 

I actually googled something like ‘charity gumball tower’ and was able to find one source for these….starting at over $1000 each.  While, I would go poor selling the one I made at such prices (labour costs coming in below minimum wage), it is interesting to note that something that starts as a handcrafted item can be produced through a mostly mechanical means at a cost that is viable from a business point of view.

This has me pondering the differences between Production work and what could be considered Research and Development.  After developing the process of building something can you recover that cost through the subsequent mass production of the item?  This would be an interesting exercise in developing a business plan around the initial cost of developing a piece of custom woodwork and then selling replicas of it at a level where the R&D costs are recovered in a short enough time to start generating profit on the items.  Hmmm!

Of course, this flies in the face of a custom woodworking business where the customer is buying the item in part because it is unique.  The question then is where does type of approach fit in?  My neighbour made a few bucks off of mass produced mirrors and rocking horses by hocking his wares at various craft shows and fairs, but this is not a viable business model.  This obviously isn’t how the greats did it…but then they have something the rest of us might just be missing (aside from thinning hair, I don’t see a lot of Sam Maloof when I look in the mirror.)  Then there is always the question of what ‘custom’ really means, it’s a big world out there, especially on the internet..can more than one person be willing to pay a lot of money for their own ‘copy’ of a custom piece?  I digress, perhaps I’ve been reading too many articles on making woodworking a business.   What would Adam King say?


Marble Tower – finished!

Yes, it is finally done.

Before I get to the finished product, I did have a few things to touch up before I even got to the finishing stage.

Final touches:

– the loading mechanism at the top needed some fine tuning and I decided to cut out most of the plywood in the supporting structure for it…it looked strange to me having a big piece of solid material right at the top.

– in a few places I needed to embellish the rails with bumpers to keep the marbles from making a premature escape from their noisy adventure.

– several screw holes needed to be plugged and cleaned up.

Once these steps were done, I had a whole lot of finicky sanding to do.  A good lesson on something like this is to prefinish all that you can.  The first 3 or 4 coats of varnish were wiped on (regular varnish thinned down with mineral spirits and applied with an old cotton sock), followed by a final coat sprayed on (spray can…not HVLP… 😦 ).

I left the finish to cure for a couple of days and buffed it out with a ‘000’ scotchbrite pad (couldn’t find any ‘0000’).  The handful of moving parts also got a light coat of paste wax to keep them from sticking.

…..and…(drum roll)…ta da!


There’s nothing quite as satisfying as completing a project.  When it’s something you can actually just go ahead and use right away, it’s even better.  But when it makes lots of noise, then it’s just awesome!

I’ve got three videos for you:

Video 1:  A tour of the tower.

Video 2:  The full effect (and my ugly mug to boot).  I’m also playing with actually editing video (which I can see is going to suck up lots of time if I start doing more videos)

Video 3:  A few close-up shots of the various parts in action.

This entire process had its ups and downs and suffered from some serious procrastination, but it was fun and I learned a lot from the process.  I was able to try out a couple of new techniques and now have a fun toy and interesting conversation piece.

Hmmm..so, what’s next???

Marble Tower – decisions, decisions

I could go on about great planning and thinking ahead and any number of good reasons for why I went ahead and put the bottom mechanism in place long before I was ‘supposed to’…but in reality, it looked like fun, so I jumped ahead and did it completely out of sequence.

Having done this out of sequence turned out to be quite helpful when I was doing the short and winding road in the previous post, since I didn’t have to guess or calculate how high it had to be when it ended, nor did I have to figure out a way to attach it.  Yea me!

This part looked like fun to me, kind of like a small section of a mechanical binary counting machine you’d find in a kid’s science museum.  Ok, I’m probably reaching, but it evoked that kind of feeling in me.  Basically the divider flips back and forth between the two tracks, using the marble’s weight to move the divider as it passes by.

I pretty much followed the plans to a T for this part.  Well, except for the little trough at the end where the marbles rest….you can’t expect me to do a whole section by the book!

No real significant challenges in this part, just a lot of thankfulness that I’ve got a bandsaw, without which I am dead sure I would have done it differently…as in not at all. 

The one area where I spent some time and did a mock-up was on the little cog-wheels.  I wanted them to be the same and had a bit of trouble making the first one look just like the template, and it ended up a little off balance in the end.  From the exercise of building one, I figured out a more straightforward way of cutting them on the bandsaw.

The plans were to have a wheel with four spokes 90 degrees to each other but each with a slight curve to them, with a cylinder stuck on the end of each spoke to catch the marble.  This is a little tedious to do, at least with my tools….(feel free to read that as skills instead of tools).  So, instead I made each spoke a bit more like a teardrop shape, which was both easier and to my eye, a little nicer – less like the old erector sets.  The cogs spin freely on some thin dowel material (bamboo skewer to be exact), which I later trimmed down and capped off.

Instead of the planned for trough, I decided to let the marbles collect in a triangular pen.  I took some 1/8″ strips of ash and glued them from the uprights back towards the center where they intersected with this last mechanism, as well as one strip across the front to keep the marbles in place. 

 I tried dry fitting the triangular pen in place and it looked pretty good to me, so I glued them down.  Yes kids, it’s lesson time!  Dry fit…glue…sounds right.  Oh wait…there’s a mechanical activity happening somewhere in there too…a marble is supposed to be involved.  The plan should have been:  dry fit – TEST – rethink – dry fit – TEST – glue.  Insert sheepish look.

Apparently the marbles are able to bounce just high enough to hop over the ash strips, only to be found several minutes later with a telescopic magnet on a stick – buried in wood shavings under a cabinet.  After several such tests and some R-rated language I cut an additional strip to increase the height enough to bounce the marbles back into their pen.

Yes, this was done out of sequence (as you can see this part without the bell and winding road)…which I will claim was planned out for your viewing pleasure.  🙂

This was the last step in build process, but I am still far from ‘done’.  The tower now actually works, but there are some glitches and there are a few things I have to go back and revisit as well as some trim work.

My next update will include some pictures of the finished product along with a flawless execution of 10 marbles through the dispensing mechanism and all subsequent ramps, toys, bells and xylophones, to end with a pile of marbles nestled in the triangular pen with nothing but the faint pealing of the bell to give away the maelstrom of activity that just took place.  Too dramatic?  No…just you wait…you’ll see!

Still don’t believe me?  Ok…here’s a teaser….and if you watch carefully at the end you’ll see my issue with the inadequate front pen rail.


Marble Tower – the short and winding road

If you watched the video at the end of the last update, you already got the preview of what the short and winding road looks like.
Going back to the plans, they wanted a board that had a routed zigzag, but once again I didn’t like it, so I took my own path.
I did toy with the idea and even went so far as to try to fit a board in place that could do this, but I found it was rather heavy – it took up a lot of visual space and blocked the view of the mechanism at the bottom of the tower too much.
While working on some finishing touches to the mechanisms higher in the tower, I came upon the idea of reusing the technique I used for making the ‘loading ramp’ for the funnel.
Essentially I took a long strip of the rail material and cut little wedges at a variety of angles and played with taping them together to make a ‘snake’.
A few attempts and I’d found what I wanted, something that was light and delicate looking that completed the path from the bell down to the last stage of the tower.

Attaching the snake was a simple task, a couple of glued straps between the rail from the funnel to the bell and the top end was secure. The bottom end took a bit of milling to get a block to join the snake to the last mechanism.
The block I chose to have a curved side to it to contrast with the generally angular nature of the tower while still imparting a bit of a mechanical feel to the joint. To me at least, the curve imparts movement, as if the snake rail somehow is hinged onto the other piece.

The curved block is not that visible in these pictures…alas, I’ll make sure it’s more visible in the video recap in a couple of more posts.
One intriguing ‘benefit’ (a rare moment of optimism on my part, calling it a benefit) of the snake rail that I did not expect is that the marble or ball does not have a smooth path, due to the angled joints. The result of this seemingly poor design is that the marble does not race down the snake with great speed, in reality it tends to wobble its way down the track.
When I first saw this, I was taken aback, it was not slick and smooth like the rest. After watching it a couple of times, I realized that I was really drawn to this part of the tower because it behaved in a unique and unusual way.
It isn’t the easiest thing to see in the video, maybe I’ll have to play with trying to get a slow-mo video of it to show it off well. but to me it achieves a bit of an inside joke that only I will really appreciate.
Not to get all Taoist on you, but far from being an uncarved block, my path as a woodworker is much like this wobbly snake…it’s not straight or smooth, but it is still a means to and end!