Thu Jan 10, 2013 10:53 pm
The following was originally posted by Fred Finisher during his Lunch Reports from June 25-29, 2012.
He was an employee in the finishing department from 1978 (CLF Research/Music Man/G&L) until Dec. 1985.
Today I will touch on the topic of finishing because this seems to be more interesting to most enthusiasts.
There have been questions as to how the finishes were applied and what was used that I would like to touch on.
For starters, let's talk about prep. Sanding is the most thankless job in the shop no matter what field you're in.
A poor sanding job will result in a poor finish and feel. A body or neck is shaped and finish sanded prior to coming
into the finish department. Depending on the species of wood, the next step is to final sand and seal or apply a paste
wood filler ( colored for Mahogany, Natural for Ash ). The filler was applied by brush allowed to dry then wiped off
across the grain with burlap in order to leave as much as possible in the pores of the wood. If this is not done, the
finish will continue to shrink into the grain of the wood and will look like an amateur did it. Once the filler is lightly
sanded the base coats can be applied after a sanding sealer is applied and scuff sanded.This is something that has
to be done very lightly at first or there will be air bubbles and other problems to deal with. Four coats of clear was
applied to create a base coat prior to any color being applied. This might come as a surprise to some but the colors
were applied over the base coats. They were not wipe on stains or sprayed directly on the wood. The base coats
until around 1985 were 100% nitro cellulose lacquer. There were no polyester or polyurethane base coats prior to
that time. After four coats were applied and dry, they had to be smooth sanded before the color ( or in the case of
natural ) and top coats could be applied. I will continue this process breakdown throughout the day. I hope you will
stay tuned.
Fred
Footnote: When I say no polys were used prior to 1985 I mean at G&L. The very first CLF instruments did have
polyester base coats which were discontinued because of check cracking.
To clear things up about what was used, all G&L guitars before around 1985 were 100% nitro cellulose lacquer finishes.
Around '85 we began to shoot a two part polyurethane for base coats only. Bodies that were made of Ash or Mahogany
were filled with a paste wood filler. This was a time consuming process but necessary to get the smooth finish necessary
for these guitars to look right. The mahogany bodies were discontinued early on when Leo became convinced that the
tone of these instruments was not as good as the maple and ash bodies. When this happened, the bodies in production
were pulled and destroyed so any early G&L's that are mahogany are from a small group that were completed prior to this
change. The bodies came into the finish department presanded by the woodshop but not completely sanded. The final
sanding took place in finishing and then they were either filled or sealed right away. A lacquer sanding sealer was used
for this. This was then scuff sanded before four coats of clear lacquer was applied as a base coat. Filled bodies had to be
coated carefully or they would get air bubbles that were hard to remedy. Once the base coats were applied, they would
need to be scuff sanded to remove the orange peel and grain that might show through.
After the sanding was complete, the color coats were done. If a body was to remain natural, it of course was merely
sprayed with clear lacquer. If it was to be colored the process could be as simple as spraying on a solid color such
as black. If it was to be a sunburst for example, you would begin with the yellow base coat over the entire body, followed
by the cherry red perimeter being careful not to get it too dark or light, then the last step would be to apply the dark brown
perimeter burst. The outside edge needed to be opaque but the face and back of the instrument had to have a certain see
through quality to it in order for it not to look like it was "masked off". There were variances in these finishes but most were
pretty consistent. The see through blues and reds were especially touchy because they could come out blotchy or too dark.
After the colors were applied, six coats of clear nitro was sprayed on. Sometime early on we began to make it a bit easier for
the polishing department by stopping before the last coat and sanding the lacquer smooth before spraying on the last coat.
This made it easier for them to remove the orange peel during the wet sanding process. Once the final coat was applied the
bodies were allowed to dry for two weeks. This made it possible to wet sand and polish the bodies to a high gloss without
worrying about the lacquer shrinking prematurely. The necks were sprayed with a total of six coats also but they were buffed
out much sooner because there was less lacquer to dry. Once we began to spray colors on headstocks, there were some
changes on how we got them complete. Although this looked better, there was a lot of wailing and gnashing of teeth over the
extra effort needed to complete them. We had a base plus bonus per piece system in place so any changes caused a lot of
heartburn with those of us who had to do the extra work.
After the bodies and necks were dry enough, they were wet sanded to a 600 grit paper using a soap and water solution. This
process took some finesse because a little too much water and the cavities and holes would swell. The buffing was done by
machine which required steady hands and focus or you stood a chance of having a high speed neck or body crack you in the
ribs or like one of the guys even worse, right between the eyes. Once the edges were polished, the top and back were polished
by a hand held buffer similar to what you see used for detailing cars. These finishes were scrutinized for defects because
nobody wanted any sub par instruments leaving the factory.
I hope this sheds a little light on what it takes to make a guitar look as good as it does when it leaves the factory.