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Ernie Jurick
 
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Default Belt sander clogging


"Dave Mundt" wrote in message
.. .
Greetings and Salutations.

I then attempted to clean up the surface with a #80 open-grit belt on my
sander. The first belt lasted 30 seconds before becoming so badly gummed

up
that I had to stop. It was literally plated with what looked like brown

wax.
The wood surface was barely touched. I cleaned the belt with a resin

stick
and tried again. Same thing. Ditto the third try.

I then switched to a small finishing sander and #60 open grit, thinking

that
the weight of the belt sander (ancient 4" Rockwell monster) was heating

up
the wood and drawing residual shellac to the surface. The small sander

ran
for about a minute before clogging like the belt had. I cleaned the wood
surface again with alcohol, then with acetone, and tried a new sheet of
paper. Same thing happened.


That sounds more like sap or something like that, rather than
residual finish.


The back of the chest isn't finished, and that cleaned up nicely, which is
why I suspect the old finish.

When you say "clean up the surface", why should you have to
start with such a coarse belt? I would think that it would have been
smooth enough from the original builder to require nothing more than
a little sanding with a 220 grit or so disk.


The wood is VERY badly stained. It looks like generations of beer glasses
had been set down on it.

I'm frankly stumped. A very knowledgable acquaintance suggested running a
propane torch or heat gun lightly over the surface to heat up, draw off

and
carbonize the remaining shellac, which could then be scraped off before I
tried sanding again. However, he admitted that he had no experience

working
with cedar this way.

No...this is what is known as a "Bad Idea". It is my general
rule to NEVER recommend a process that I have not had some contact
with, although I might say something like "well, I heard that one
can..."
What will likely happen is that you will end up with a random
pattern of scortch marks on the wood that STILL will have to be
removed. It is possible to use heat to remove a finish, but, it
can be a tricky thing.


I'm glad I asked. :-) I did a lot of online research on eastern cedar last
night, and you're right on the mark. Heat would have ruined the surface and
I'd be living in the doghouse for months.

I thought I would ask this incredible group before going the torch route.
It's a family heirloom and I'm likely to be lynched if I screw it up. Any
suggestions appreciated.
-- Ernie


Yea...that can be a problem with things of sentimental value.
I would suggest this course of action. Put down the belt sander.
If it is necessary to smooth surfaces back down, I would STRONGLY
suggest using a scraper. It will do a great job, even on this
challenging wood. I would ALSO recommend that you pick up
a chunk of similar wood from your local lumber yard and experiment
on it for a bit, figuring out how to sharpen the scraper
to an appropriate angle, finding the correct amount of hook,
etc.
The big thing is not to mess with it too much. Got to
remember that Cedar is not a very hard wood, so, it is a waste
of time and energy to try and get all the dents out. You will
just lose valuable thickness, and, end up with a smooth
surface that will quickly accumulate a NEW set of dents and
dings.
Unless there is serious damage that needs to be
repaired, my usual course of action on a piece like this would
be to simply strip off the old, crappy finish, and redo it
without really doing much to the wood itself.
Sorry for rambling a bit...it has been a bad
day...


I appreciate the pointers, Dave. I have a set of Swedish scrapers and a
burnisher I used to use back when I was making furniture. It never dawned on
me to use them for refinishing.
-- Ernie