Polyester Repair

[David ilvedson]

> Date:          Mon, 11 Aug 1997 15:38:11 -0500
> To:            pianotech@ptg.org
> From:          skroeker@MTS.NET (Stan Kroeker)
> Subject:       Re: Polyester Repair
> Reply-to:      pianotech@ptg.org

Thanks Stan for the informative post.  Thanks to Paul, Phil and 
others for their info!  I think I'll take the plunge...

David ilvedson, RPT
Pacifica, CA

> >> Date:          Sun, 10 Aug 1997 13:23:08 -0500
> >> To:            pianotech@ptg.org
> >> From:          skroeker@MTS.NET (Stan Kroeker)
> >> Subject:       Re: Polyester Repair
> >> Reply-to:      pianotech@ptg.org
> >
> >Stan,
> >
> >I would like some advice on buffing out polyester pianos.  What
> >kind of buffer is the best.  Polishes?  What to look out
> >for when attempting this work.  I have many pianos that could
> >really benefit from this work and I would like to be able to
> >offer the service.  Many years ago I help prep pianos for a
> >dealer at a "warehouse".  They had a great touchup man who used
> >this hand-held electric buffer.  I believe he squirted on some
> >kind of a polish as he buffed the finish.
> >
> >Thanks in advance...
> >
> >David ilvedson, RPT
> >Pacifica, CA
> 
> David,
> 
> I own a Black & Decker (industrial grade) 'Buffmaster' electronic polisher.
> Although the Milwaukee mentioned in another post is a high quality machine
> as is the Makita, they are quite a bit more costly than the B & D.  Look
> for a machine with variable speed (mine is 0 - 3000 rpm).  I think they all
> have trigger locks which make for less discomfort during long buffing
> sessions.
> 
> Another post mentioned the foam pads which attach to the buffing adapter
> with velcro (I think 3M makes these 'Hook-It' pads).  Although I have not
> used these, I have heard encouraging opinions.  My understanding is that
> these pads work best in the final stage of polishing.  For more protracted
> repairs and scratch removal I believe the flannel wheels charged with the
> appropriate compound are more efficient.
> 
> These wheels also require a special adaptor to attach to the spindle of the
> buffer and are designed to buff on the edge of the wheel rather than the
> face of a bonnet type.  The Menzerna compounds I use come in bar form
> (should be available from your Konig distributor) and are applied to the
> edge of the spinning wheel.  When buffing on the edge of a 10" wheel, a
> great deal of heat is generated and the machine must keep moving across the
> part being polished.  The wheel must be cleaned of old compound after
> roughly 15 minutes of buffing either with the use of special 'rakes' or
> simply a dedicated wire brush held against the rotating wheel.  If you use
> different grades of compound it is best to have a separate wheel for each
> grade.
> 
> In practice, I prefer to go from the finest sandpaper (1500 micro-fine)
> directly to the finest polishing compound.  You must evaluate each piece
> being buffed as to whether the scratches are fine enough to simply buff
> out, or whether they must be wet sanded first.  When buffing the rather
> large sanded area that results from a relatively small polyester patch, it
> is recommended that you polish the patch area using the hand applied
> rubbing compounds (part of the Konig kit) and then use the machine to buff
> the rest of the area.  This avoids the need to wait 24 hours for the
> material to cure to its hardest, and minimizes the risk of shrinking the
> patch with the heat generated from the buffing wheel.
> 
> After machine buffing there is usually a great deal of compound dust
> sticking to the static charged cabinet.  I sometimes use Windex on a
> polishing cloth to pick up most of this dust and then polish by hand with
> the Cory High Gloss Polish.
> 
> Hope this helps,
> 
> 
> Stan Kroeker
> Registered Piano Technician
> 
> Kroeker & Sons Piano Experts
> 59 Quiring Bay
> Winnipeg, Manitoba
> Canada  R2G 1Y5
> 
> Ph.   204-669-5881
> Res.  204-661-5621
> 
> 
> 
>