It’s at Wal Mart. It’s aluminum, and 9" around. The sides are straight. And just as importantly, the bottom has a 1/2" bevel to it around the outside edge.
The only issue with it is that it’s 3" deep. However, this may not actually be a bad thing, because you could recess it inside the pack,and then slip a 1/2" wide ring around it and you won’t have the lip to interfering with things. You’d only need 1" of clearance inside the pack for the excess, and even on a wood pack made of 1/2" MDF you should have at least 1 1/4" of clearance, and if you used thinner materials you may have as much as 2 1/4".
Now my only problem is figuring out the easiest way to make that 1/2" ring around it. One thing I’ve considered is those crochet hoops. They make them with a 10" ID, and the two hoops together are 1/2" thick. But there’s metal rivets in the outside hoop you’d have to grind off.
I don’t want to use foam, and I’d rather not try to cut out a 1/2" thick ring from 1/2" thick MDF. That would take tons of sanding to get round. I also don’t suppose it’s possible to wet and bend a 1/2" thick board. Would have to work with 1/8" or less I’d imagine. Mayyyybe you could bend 1/4". Guess I’ll have to research that.
Man it sure would be nice to have access to a CNC machine.
Oddly enough, I asked a guy who worked in the tool department at Home Depot what bit you would use to cut shapes out with a router and he said routers couldn’t do that. Then he tried to sell me a Dremel. On two occasions. I already got one from WalMart though and found out they’re complete ■■■■.
So what bit would one use to cut a hole with a router? And how do you make sure you stay on the line? The router I have access to doesn’t look like the bit would be easily visible while cutting.
Oh, and I’d really rather not make the cyclotron out of wood. It would add a lot of weight to the pack and more importantly, I’d have to buy a 1/2" bevel bit for the router just to do that one edge, and those bits are expensive. But I might be able to convince myself to get a bit that I can use to cut holes, that’s more useful in general.
As for how to cut circles with a router, you make a compass out of the router…
You make a thin base mount the router on it, measure back for the radius and drill a hold through the base and through the material to mount a pivot point…
Just Google up cutting a circle with a router… You can also browse yourtube and see videos…
the bit would be called a rabbiting bit…im pretty sure thats what its called…they are long and straight, with varying diamaters of course…and to stay on the line you would just have to make a simple jig…you could even take a small bowl or spray paint cap (depending on your router size) and attach it to the board..just as long as it puts the center of the bit on your line…just have to find something the right size..then follow it around with the router.
I watched enough This Old House and Yankee Workshop when I was a kid to know the Home Depot guy was full of crap, but I couldn’t find a bit on the shelf which indicated it was for cutting holes. Now that I know what one looks like maybe I’ll have more luck.
