I have an old Premier xylo in for refurbishment.
First job is to refinish the note bars which have water damage in the varnish. So the bars are stripped of all the old varnish
Day 1: There are three ways to remove varnish: heat, abrasives, chemicals. Heat poses a high risk of scorching the wood. Abrasives alone get clogged up, so a lot of material expense unless very coarse abrasives are used, but they have too much effect on the dimensions of the note bar and thus dramatically affect the tuning. My preferred method is a paint stripper, they are pretty much all water based now. It is a sticky messy job, and time consuming, but effective. After scraping off as much varnish as possible, the note is washed in soapy water to neutralise the paint stripper, then left over night to dry.
Day 2: Start sanding, and keep sanding way past the blister stage, way past the point of boredom. This is the tedious part, concentration is needed to remove the last bits of varnish, then they need to be cleaned up of the whitish residue, and any surface imperfections removed. I do this all by hand, its the only way. Any light weight sanding machine (orbital or palm sander) will leave little circular marks that look awful – and I’m not employed to make stuff look awful. A belt sander will be way too aggressive. I do have two machines that I built for use when re facing note bars, one of which takes off 0.07millimetres each pass, even this is too aggressive for re-finishing! At this stage I also repair any edge damage.
Day 3: Yep still sanding and feeling insane! However they will be finished today.
After all the prep work is complete, I do a primary tune. This is one cycle through all the notes to bring them back up to pitch. It is easier to tune things that are too sharp, but more invasive bringing notes up from flat (which need to be made shorter). I do this at this stage so that the ends of the bar can be varnished, without the need to re-seal them when I come to properly tune the bars later.
Once tuned, I wipe off all the dust, then start varnishing.
I do all sides except the face on the first run, then leave them overnight.
Day 4: De-nib the notes, which means lightly sand with fine abrasives to remove any dust particles that landed on the wet varnish, thus creating a “nib”. Then I varnish the faces with the first coat.
Day 5: De-nib, varnish bottom and sides.
Day 6: De-nib, varnish face.
Day 7: De-nib, varnish bottom and ends (not sides).
Day 8: De-nib, varnish faces and sides. Have a celebratory beer, the varnishing is complete. I then put them to one side for as long as I can to let the varnish cure prior to tuning.
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