The spinner problem is an interesting one.
I've not built a homemade spinner or purchased a commercial one.
I've thought about this a lot, and have narrowed my thoughts to something like the following:
a) Given my handiness, making one myself would be prone to error, either in time, redos, or quality. Maybe not an issue for you.
b) Even given a successful build, I would be inclined to think that the quality of specifically-machined parts in a professionally designed and built spinner would still be greater than the hacked parts I can find lying around. (I've never seen one of OSCAR's spinner, but the mounting plates are a force to be reckoned with.)
c) Moreover, It seems to me, from some of the research I've done, that if you don't already have tools and/or some parts (like a viable non-working HDD), it's nearly a toss-up pricewise to just buy, say, an OSCAR model 3 or something.
d) Even if you build one yourself, you still have to procure a top; new you're looking at $15-20 plus shipping all by itself. (There IS thenasty's interesting bunnytop (
http://www.arcadecontrols.org/yabbse/index.php?board=10;action=display;threadid=17522); it works surprising well, but might throw off the arcade experience for the purist.)
d) Another possibility is to buy used (see the buy/sell forum) or to buy a real arcade spinner and hack it. I seem to recall a lone Tron spinner on ebay a few weeks ago going for like $10 to $15. You should be able to rig one of those up with one of OSCAR's decoder boards ($7.50) (plus a wiring harness if you can't build one yourself) and be good to go. Shipping could be a killer going that route.
Given the presumed quality of OSCAR's spinners (which are cheaper than the SlikStik one, not trying to imply anything there, just presuming an inexpensive route), you would likely be happiest just saving your quarters for another month or two and going with one from there.
But perhaps the more adventurous folks who have actually built a spinner should chime in here

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b