Homebrew PCBs

Tony, outstanding link.

Thanks. The same bearings from McMaster Carr are twenty times the money. :-0

Turns out the specs on the ABEC bearings has only to do with OD and ID, etc., nothing on runout I can find. Not that it matters much, really; I'll use bearings that are rigid and bearings that are spring loaded to oppose, and flat stock, and side bearings to maintain alignment, and it should work fine; the only thing I have to be careful to avoid is super fast bearings with "loose" balls, but that shouldn't be much of an issue.

Best, Charlie

--- In Homebrew_PCBs@yahoogroups.com, "Tony Smith" <ajsmith@...> wrote:
>
> > Hi Charlie,
> > 
> > I would use skateboard bearings. They are available in ABEC7 accuracy
> > for very little money. Skate bearings are standard 608 size metric
> > bearings, 8mm bore 22mm OD 7mm thick.
> 
> 
> ABEC7 (in a skate shop) is a marketing gimmick.  For skating you want 'crap'
> bearings as free running is more important than run-out.  That rating is for
> high-speed spindles, hence the price.  ABEC1 or 'precision' bearing are good
> enough.  
> 
> The rating has nothing to do with quality either.  Consider sealed (rubber)
> instead of shielded (metal), they keep the dust out better.
> 
> See www.vxb.com, they'll sell you 100 sealed bearings for $35.  (Skates need
> 16 bearings, boards 8, hence the odd pack sizes.)
> 
> Tony
>