Brian Mills's marble run blocks (based on these plans)

Brian writes:
Hi Matthias

I purchased a set of your marble blocks plans and decided to build a set for my grandson Elliot (2 1/2 ) for Christmas 2014. Thought I’d share some pictures and thoughts / comments on my build.

Your plans are excellent – very detailed and precise. Speaking of being precise, I found that this build challenged my perceptions of precision in woodworking. “Close enough” just would not cut it here! It took a lot of tweaking, and more than one re-start, before I was able to reliably produce parts of sufficient repeatability and accuracy.

I personally found one of the trickiest operations to be drilling the holes for the pins to fit into. Just getting those in the exact right place was, on occasion, frustrating. I have a drill press, and even made up a little squaring fence jig to help, but finally found that being very fussy about layout, and then centre punching the hole locations, was the best way – even with the Forstner bits.


I decided to go with a ‘standard’ half-inch dowel for my pins (vs. turning my own custom sized dowels). This meant that the mating holes had to be slightly over ½” diameter. I achieved this by first drilling the holes, then using a small Dremel tool sanding drum to enlarge the holes. Less work than it sounds like, and this actually gave an opportunity to tweak the hole location a bit for better fits as needed.

I actually used a mix of various scrap wood for the parts – some poplar, but mostly spruce from 2x4 offcuts (I knew I was saving those for a reason!). This all seemed to work, and the total cost of wood for this project was $0. My favorite price point! I love recycling / upcycling wood like this – making something useful or beautiful from scrap or even someone else’s garbage…

I really wanted to make the blocks bright and colourful, so I bought several cans of high-gloss spray paint and painted everything. This was a very time-consuming process, as over 100 parts needed several coats of paint. I build a “spray booth” out of a large box from a new BBQ , connected to my dust collector (which vents outside – which, by the way, I highly recommend) to control the odor / overspray – my shop is in my basement, like yours – and this worked really well. I found I had to sand all the parts to 400 grit to achieve the high gloss look I wanted.


As a final touch – and this was my wife’s idea – I built a base or tray. This was just ½” plywood (scrap again) banded with some fancy trim. I lined it with felt, stuck on with spray adhesive. Also, I had the trim extend about a 1/4 “ below the base plate, and sized it so it would fit snugly on top of an Ikea “LACK” end table. This contains the marbles, makes it a self-contained play station, and the whole thing can be easily tucked away and the table used as a kid’s play table.

I didn’t take “build” photos along the way, but I’ve attached some pictures of the finished product. My grandson just loves it! He plays with it all the time – at his age he needs adult help setting up – but he is fascinated.

Couple of final comments – Some photos of suggested marble run layouts might be helpful – at least at first – it took a while to get the hang of how things could be fit together to make a layout. Also, and this could be because I used gloss paint, I find that the smooth blocks are too smooth – so the layouts will fall apart after using them for a while. It might be better to have some support blocks with the pins / holes to help lock everything together better. I might make some of these going forward – I can see myself adding to the basic set over the years. I have some ideas for ‘musical’ components which would add some interesting sounds to the mix…


Thanks again for your great website, videos, and plans.

Best Regards

Brian Mills


Matthias comments:

Measuring carefully and center-punching is what I always use for getting holes positioned accurately as well. I find that more accurate than using a drill press fence and stops.

High gloss varnishes can be more slippery, which is not ideal. I used thin coats of spray paint, which makes the varnish less smooth on mine (and also much less work to do). Use of heavier hardwoods also helps to keep the blocks from sliding around.


See also:


More marble machines

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