Hey I'm Jonathan and this is rad-head and today I'm gonna build this pendulum array,
known as a pendulum snake.
I was always intrigued by these demonstrations, so I've decided to build my own compact version
to put on my desk.
I also made a second video in which I try to explain how this actually works.
There's a link in the description, please check it out.
The base and the pendulum holder are made
of some scraps of oak veneered plywood.
I started by gluing the template using a generous amount of glue stick.
We don't want the template to peel off before we're done cutting.
Using a jigsaw I started cutting the serrated side of the template
trying to cut as close to the line as possible without touching it.
I find that using fine teeth blades, usually meant for metal
results in a much cleaner cut.
Using a sanding block I sanded up to the line.
I secured the the whole part on its side and started transferring the relevant markings
from the template to the plywood using a square
then using a center punch I made a small divot
that will help when drilling the holes.
I drilled the outermost holes using a 2.5 millimeter drill bit, and the center holes
using an extra long 3.5 millimeter drill bit, to make sure it will go all the way through the part.
I started cutting the other side and made sure I'm staying about half an inch from the
template, you'll see why in a second.
When removing this piece we reveal the extra long holes we made earlier.
They'll be used as guide holes when drilling part way through from the other side using
an 8 millimeter drill bit.
Then I finished tracing the template with the jigsaw.
Because the previous holes were drilled on a weird angle, the cuts weren't exactly clean.
That's why I waited until now to cut right to the line and reveal these nice-looking holes.
After some light sanding I center punched and drilled the holes for the legs
using a 5/8'' forstner bit
In order t o remove the template I soaked the paper with mineral spirit using my lucky sock.
After a few seconds the paper peels right off
I mixed up a small amount of 5 minutes epoxy and glued two small eye hooks in the outermost
holes of every section.
The reason I'm gluing these hooks instead of screwing them is because there's simply
not enough room for screwing the hooks that are in the inner corners.
From the other side I screwed some m4 bolts in the center holes, so that they will just
poke out the other side.
We'll see what these are used for shortly.
Now I started working on the base.
I cut the plywood to the desired dimensions.
I marked where I need to drill the four holes to connect the legs.
Using a sharpie I marked the depth I want to drill to on the forstner bit itself
that way it's easy to make repetitive holes.
For the legs I used some 5/8'' copper pipes I've cut them to length with a pipe cutter
and went over them with steel wool to give them some shine.
After two coats of spray lacquer both the plywood and the copper, it's time for assembling
Now I can start working on making the nine pendulum weights.
Using a cutoff wheel on my angle grinder I sliced a 35 millimeter diameter steel rod
into 13 millimeter thick slices.
The angle grinder leaves kind of a rough surface, so I sanded each face on the belt sander.
In order to prepare the weight for soldering, I roughened up the surface a little with file,
then put on some flux and finally a couple of pieces of solder.
I made a small loop from a piece of metal wire.
Using an oxy-propane torch I heated the weight until the solder melted, then I dipped the
small loop in some flux and carefully placed it on the molten solder using a pair of tweezers.
After it cooled down, I went over it with a couple of coats of matte black spray paint.
In order to connect all nine weights in very specific distances, I came up with the following system.
I fixed some measuring tape to my work area and started laying out the string
marking it both at the desired distance and at the zero mark.
Now all I have to do is align the two markings in order to get to the desired length.
After threading the string through the weight and the two eye hooks, I made a simple knot
making sure to align it with the two markings from before.
This system is good to get the weight roughly in the right distance, however this is definitely
not enough for our purposes.
That's why I've added the m4 bolts earlier.
I designed and 3d printed these plastic caps to go between the bolts and the strings.
Now when we turn the bolts we have fine control over the pendulum's lengths.
After connecting all 9 pendulums and fine tuning them, this is what we get.
Build plans and 3d printable models for this project can be found on my website
If you're interested in buying something like this
I'll leave links to similar products in the description
And don't forget to stay tuned for my next video in which I explain the physics behind this
If you enjoyed this project and want to help me produce more like it
please consider supporting me on patreon
Until next time.
Bye
Không có nhận xét nào:
Đăng nhận xét