Re: Blade tracking problem
|
Few comments on bearings - Deep groove bearings
10mm and above are covered by ISO standards with radial internal clearances designated, in order of increasing clearance, as C2, ¡®Normal¡¯
or CM, C3, C4, C5 & C6; while bearings less than 10mm are considered
¡®miniature¡¯ and the clearances are designated MC (for Miniature Clearance), MC1
MC2, MC3 MC4 etc.? MC3 is considered the
equivalent fit to Normal (thought the actual clearance numbers are
appropriately smaller
- ABEC scale is a
bearing industry standard for manufacturing tolerances on every measurable dimension
except radial internal clearance. Higher ABEC ratings allow those
bearings higher operational speeds, in excess of 30,000rpm, but no more load
and even less shock resistance. ABEC 1 are cheap and fail?more?quickly, these
are what you will get if you do not ask for better. ABEC 3 or 5 are usually
better manufactured and still reasonably inexpensive.? You¡¯ll pay 5-10x as much for ABEC 7 or 9 for
absolutely no measurable difference in performance over ABEC 3 in a 4x6. You
can even buy an ABEC 9 bearing with C5 radial internal clearance (for high
speed roller skates) that is worse for side guide rollers than a much cheaper
ABEC 3 with C3 radial internal clearance.
Right now McMaster-Carr has ABEC-3 6062-RS bearings for $13.11USD apiece.? ABEC-1 bearings are $6.28.? The maker(s) are not specified.? McMaster is one of the fastest shippers I have dealt with.? Probably not true for folks outside the US.
BTW, the manual for my HF 4x6 does call out the bearing types for the drive shaft.
Mark
|
John Vreede