Introduction: Net Swing+rotating Anchorage (from Scratch)
Last year, having missed both my niece's and nephew's birthday, I wanted to make it up for it when visiting by the end of the year.
So I decided to build them a net swing!
It could either be used as a swing, or a their chill/reading nest.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Gathering Materials:
This project was the occasion to try my hand at bent lamination techniques.
And if it turned out well, I also planned on a rotating device for anchorage. (which is removable)
So first things first, after reviewing different swings dimensions available on the market, I had an idea of the size I wanted my hand built one.
Then I had to look for what would be appropriate in my garage.
As far as wood was concerned, I pretty much choosed the biggest piece that I had (from previous salvages) It was 134.5cm long, just above 14cm large, and around 5cm of thickness. and worked my way with this dimensions.
I had plenty of metal bits salvaged from a GSM pole reinforcement done at work earlier in the year. I used a small amount of a 5mm thick plate, and some corner iron (35mmX35mm).
I also needed some nuts and bolts, bearings, and chunks of wood to dress up the assembly. (I'll cover this up at corresponding chapter)
For the tools, I used a circular saw (fixed under a homemade table), drill press, hand drill, welder, angle grinder, and all sorts of handtools (saw, chisel, hammer, brush, clamps...)
Step 2: Making the Wood Stripes:
I first checked for the flexibility of different thickness of wood (with leftovers from other projects), for the diameter that I'd choose for the wooden ring. (tested a 100cm and 120cm of diameter) Figured that I could go with almost 5mm thick stripes without to much bending issues.
The idea is to end up with enough stripes to do 3 sections of the circle covering 120° each. In fact a bit more for afterwards joining.
My cuts were not pretty accurate, since my saw could not go through, but
mostly because the wood wasn't that straight (due prolonged weather exposure), and therefore could not be perfectly replaced once switched over for the second half of the cut, unless recalibrating the guide. Which I didn't do because it would have taken ages to accomplish...
So I managed to get 21 stripes of about 4mm thick, in my 14+cm piece of wood.
21/3=7 So 7 stripes by sections Therefore, a slightly under 4cm wide ring.
Which happened to be "perfect", since the outside diameter of the ring (2x3,14x64=402) was the most I could go with that 134cm long piece of wood (402/3=134)
(I have to admit I wasn't that much confident with those dimensions, because they did not let much room for error) :)
Step 3: Laminating:
I did a very rough template with every thing I could get my hands on (didn't had much, and didn't want to purchase anything).
Then tested to bend without glue. Turned out ok.
When glueing, I got rid of the outside part of the template, and added a truck slack. It was much easier to bend, and maintain in position. (and my template was really dumb, and kind of broke...) Clamps were good freinds here.
Ended up with 3 correct sections, long enough to make a full ring by joining them together.
Step 4: Joining:
I made a simple tenon mortaise joint, at a slight angle (hard to see the draw line on picture, sorry), so that it can not really get out of the mortaise.
Glued it all together. (had to fill up some gaps with small pieces of woods before clamping, because of some bad cuts)
Step 5: Metal Strapping:
At this point you might think that my wooden ring would not be strong enough to sustain human weight (kip in mind it is meant for children though). And I agree entirely. Which is why I intended to strappe some metal around.
So once I checked the perimeter, I cutted a corner iron in two (lengthwise), and welded them together, once pierced at predetermined points. (had to add another small bit of corner iron to cover the full perimeter).
I had determined this holes, to match with the net weaving, so that I would be able to make the rope go through the metal and the wood. (had to drill 12 holes)
The weaving was based on a dreamcatcher model. (there are plenty of tutorial for that...) I choosed that for deadline reasons. I had 3 weeks to do the entire project, and weaving was my biggest fear of all, so I picked what seemed to be the easiest and fastest solution. Not putting aside aesthetics though. (will come back to it)
Once welded, strapping it around the ring wasnt the most plaisant part.
I had a 4+meters stripe to handle, with tendances not to cooperate.
I figured I would use the truck slack again. Layed the stripe on the slack, clamped it all the the ring, and then rolled the ring onto it, to wrap it around. It worked, but I couldn't apply enough force on it to bend the metal thight to the ring. I had small gaps here and there. Therefore the stripe did not cover the full ring (had a 2cm gap to join both ends)
I then decided to wrap it on the inside of the ring, to force it on a better match once put back on the outside.
It made the adjustement easier, and allowed me to wrap it and secure it with screws as i did. but I still had some gaps (because the ring was probably not a perfect circle, and the inside shape had different variations than the outside shape). So I simply added a small piece of metal to weld it all together.
Once done, I drilled the ring through the holes where the rope will go.
Step 6: Sanding, Wood Finish, and Weaving:
Since the metal strapping was not a perfect feat, I sanded the ring after secured in place. This way I adapted a bit the shape of the ring to the feat of the metal.
I applied some white vinegar (macerated with iron powder from my previous cuttings), and some wax (because i had a small pot of it to finish).
So as I said before, I weaved the rope (6mm of diameter, 200+kg of resistance, but not the best to work with... time did not play in my way once again when it came to selection) in a dream catcher kind of way.
I adapted it a bit. I often double the knots, or made different ones (I used clove hitch a lot, or half hitches, etc)
The main difference, is that I weaved a smaller string inside the dreamcatcher pattern. Using the same kind of knots again, but not working in circle. I instead weaved back and forth, from outside to inside to outside again. A quarter of the circle at a time. Working on the opposite quarter every time I'd finished a back and forth motion.
Step 7: Rotating Device:
The idea there is to make a two part anchorage.
The upper part being the one that supports the net swing (ropes attached to it). And the one that is free to rotate, while maintenained by the lower part, whose attached to a fixed anchorage (tree...).
I think that for this part, I will let the pictures speak, because I fear that I might not be able to properly explain myself... (Not in English anyway...) :)
Step 8: Both Combined. End Result
Worked out pretty well, even if not perfect int therms of finitions (lacked a bit of time). Pretty sturdy aswell! I did test it myself. I'm not that heavy though...
Spins nicely without much noise.
Kids seemed to like it, but they will certainly appreciate it better in summer :)
Hope you liked it...
PS: Sorry for the poor quality of the instructabe (made it in a hurry again...)
And I think the videos don't work (can't fix it right know, I'll look into it)