DIY Platter

[dimkasta]

I understand what has been done there, but static balancing is not the same as dynamic balancing. Would you balance a car wheel with a spirit level, and why do manufacturers usually take such trouble to carry out dynamic balancing of platters? The potential out of balance forces may be relatively small, but in vinyl replay the displacement and forces involved at the stylus are tiny.

I don t know if TT companies claim to dynamically balance their platters, but my guess is that it is either marketing BS or just something to care for a public opinion creating problems.

Static balancing balances a rotating object on its X axis, taking into account weight differences around the nominal disc surface.
Dynamic balancing also balances it on its Y axis, caring to separate balance inconsistencies scattered on the Y axis and account for them individually on the X axis balance.

The smallish speed, the shallow height, the rigid and consistent material and the static Y axis makes dynamic balancing rather irrelevant on a TT platter.
Car tires is a different thing because we have a highly elastic material with inconsistent density and significantly bigger height, spinning on high speeds and alternating Y axis.

Anyway, to my knowledge, the SL1200 platter is not even statically balanced, so even statically balancing it should be enough and a big improvement as it is...

We can statically balance the platter by tilting the TT at around 40 degrees, and slowly spinning the platter. The heavier side should slide at the down side and the platter should swing a bit on that spot before stopping rotating. We need to add some weight on the opposite side. We repeat that until we have no swinging effect because of heavy areas drawn to the bottom by gravity.
Careful no to damage your spindle with the side forces.