I've had a lot of interest and since I've now made back my investment in tools, I thought I would explain the process so that any of you that think you're up for it can try making your own. I know there are many other ways to do this, but this is the method I use and works pretty well.
Tools needed:
Drill Press(adjustable speed that can go below 1000 rpm)
4-1/4" hole saw(2" tall) (found mine at Lowes for $45)
2-1/2" hole saw(2" tall) (Lowes, $35)
Arbor/pilot bit for hole saws (Lowes $16)
Some sort of chamferring bit. I use a cone shaped high speed dremel bit, but a router bit would work also.
Materials needed:
1 square foot of 1-1/2" thick(or whatever thickness you want) UHMW Polyetheylene. This stuff is super tough, easy to work with, will never break down and is lightweight. I got mine at
www.MSCDirect.com for around $40 for a sheet that small.
Armorall(lubricates the bits very nicely).
Two 1" tall rings of 2-1/2" diameter radiator hose(Advance Auto Parts, $12 for the only 2-1/2" hose they have).
Total: around $108 if you need to buy everything from scratch, not counting the drill press)
Now that you have collected all the parts and tools, let's make some spacers!
Put the 4-1/4" hole saw on the arbor, then chuck it into the drill press. Turn the press speed down as low as you can, I use 750 RPM. Any faster and you melt through instead of cutting through. Now cut out 4 disks from your material. Stick as close to the edge as you can so the saw actually sticks out the side of the material without interferring with the roundness of the disk and it will cut much faster as the sawdust has an exit. Cut the last 1/8" from the other side and the plug is much easier to get out of the saw. Go slow and easy and squirt armorall as needed into the cut to keep the saw spinning easily.
Now you have four 4-1/4" round, 1-1/2" tall disks. Let's bore them out!
Change the arbor to the 2-1/2" hole saw and chuck it into the drill press. Now using the same hole in the center left by the arbor's guide bit, cut a 2-1/2" plug out of the center of each disk. Again using armorall as needed and cutting the last 1/8" from the other side. Once you have all 4 bored out, you might want to clean up the inside surface a little. I use a dremel with a drum sander.
Now you need to chamfer the inside upper edge so it fits in the spring cup. I chuck a cone shaped high speed dremel bit into my drill press to do this, but you can also use a router bit or even the drum sander on a dremel. The chamfer needs to be around 1/4" to fit all the way up into the spring cup.
There! Now you have just made your own coil spacers! Clean up the edges if you like and slap those puppies into your ride!(be sure to get the alignment checked after install).
You can save money off of the $108 total if you can find the material cheaper or use scrap from a machine shop and if you happen to have the hole saws already, there's even more savings. I would not recomend using wood or regular plastic, they just aren't durable enough, and aluminum doesn't cut very well with holesaws.
So if you think you're up for it, go to it and good luck!
BTW: I still have a few sets available for sale in the garage sale forum if this sounds like too much work!
LOL!!!