Measuring tools and instruments often come in wooden cases. I've seen
mahogany, birch, poplar, pine, and several other woods used. The idea
is that the case will absorb moisture from the tool and thereby keep
it from rusting. Usually, these boxes are finished with a varnish on
the outside, and less often, on the inside. When the inside is not
varnished, it is usually left bare. I'm reasonably sure the original
finish is a varnish, because I've tested for shellac with denatured
alcohol, and these boxes generally predate polyurethane.
When I buy a used instrument the box is often in rough condition, and
I like to put them back in good shape by regluing, sanding, etc. I've
been leaving the inside sanded but unfinished (no coating of any kind)
and spraying polyurethane on the outside.
1) to maximize the water absorbtion, should the inside of the boxes
be left unfinished?
2) to maximize the water absorbtion, should the outside of the boxes
be left unfinished?
3) Is clear gloss sprayed polyurethane a good choice for finishing,
given that the water absorbtion issue is much more important than
protecting the finish of the box?
4) For making a new box from scratch, what wood choice would maximize
the water absorbtion?
5) I've seen some pretty old tools with ground cast iron faces arrive
inside intact boxes without rust, so I'm kind of tempted to believe
the whole water absorbtion idea. If anyone can substantiate this
theory, or offer an alternative hypothesis, I'd be very grateful.
I've cross-posted to our brethern over in rec.woodworking since they
have specialized knowledge of woods, as well as a shared deeply-held
hatred of rust on tools!
Thanks very much!
Dave
On Aug 9, 1:25 am, LowEnergyParticle <[email protected]> wrote:
> Measuring tools and instruments often come in wooden cases. I've seen
> mahogany, birch, poplar, pine, and several other woods used. The idea
> is that the case will absorb moisture from the tool and thereby keep
> it from rusting. Usually, these boxes are finished with a varnish on
> the outside, and less often, on the inside. When the inside is not
> varnished, it is usually left bare. I'm reasonably sure the original
> finish is a varnish, because I've tested for shellac with denatured
> alcohol, and these boxes generally predate polyurethane.
>
> When I buy a used instrument the box is often in rough condition, and
> I like to put them back in good shape by regluing, sanding, etc. I've
> been leaving the inside sanded but unfinished (no coating of any kind)
> and spraying polyurethane on the outside.
>
> 1) to maximize the water absorbtion, should the inside of the boxes
> be left unfinished?
> 2) to maximize the water absorbtion, should the outside of the boxes
> be left unfinished?
> 3) Is clear gloss sprayed polyurethane a good choice for finishing,
> given that the water absorbtion issue is much more important than
> protecting the finish of the box?
> 4) For making a new box from scratch, what wood choice would maximize
> the water absorbtion?
> 5) I've seen some pretty old tools with ground cast iron faces arrive
> inside intact boxes without rust, so I'm kind of tempted to believe
> the whole water absorbtion idea. If anyone can substantiate this
> theory, or offer an alternative hypothesis, I'd be very grateful.
>
> I've cross-posted to our brethern over in rec.woodworking since they
> have specialized knowledge of woods, as well as a shared deeply-held
> hatred of rust on tools!
>
> Thanks very much!
> Dave
There is no "water absorbtion issue."
Wood reaches equilibrium water content with its surroundings--most
air, damp wood, dry air, dry wood--and most of what it absorbs comes
from the air around it, not the tool stored inside. In other words, if
you're storing a tool in a humid climate, the wood is going to reach
equilibrium with that climate and will most definitely not absorb any
more moisture to protect the wood. Wood as a rust preventer works well
in Arizona deserts (no rust prevention needed). It's not helpful in
Atlanta or New Orleans.
Wood has traditionally been used to protect measuring tools and
similar instruments from physical damage other than rust. Wood doesn't
absorb water well enough to work as a dessicant. Period. Buy a
reheatable dessicant if you want water absorption. Old tools in wooden
boxes that come through rust free were almost certainly stored in
areas of low humidity.
Jim, JT, and Charlie,
Thank you all very much! I'm going to treat the wooden-box-as-rust-
preventer story as hogwash and finish boxes inside and out with
polyurethane. Furthermore, since I live down on the Gulf Coast near
Houston, where humidity sometimes presents a small problem, I'm going
to buy a case of those small cans of reheatable dessicant and clip one
inside every box.
Thanks very much for the help.
Dave
On Aug 9, 7:58 am, LowEnergyParticle <[email protected]> wrote:
> Jim, JT, and Charlie,
>
> Thank you all very much! I'm going to treat the wooden-box-as-rust-
> preventer story as hogwash and finish boxes inside and out with
> polyurethane. Furthermore, since I live down on the Gulf Coast near
> Houston, where humidity sometimes presents a small problem, I'm going
> to buy a case of those small cans of reheatable dessicant and clip one
> inside every box.
If the original finish wasn't poly, I wouldn't use it, just for
authenticity's
sake. For new boxes, use whatever finish you like.
For ultimate slickness, install humidity gauges, or store tool
boxes in a cabinet outfitted with one.
On Aug 8, 11:25 pm, LowEnergyParticle <[email protected]> wrote:
> Measuring tools and instruments often come in wooden cases. I've seen
> mahogany, birch, poplar, pine, and several other woods used. The idea
> is that the case will absorb moisture from the tool and thereby keep
> it from rusting. Usually, these boxes are finished with a varnish on
> the outside, and less often, on the inside. When the inside is not
> varnished, it is usually left bare. I'm reasonably sure the original
> finish is a varnish, because I've tested for shellac with denatured
> alcohol, and these boxes generally predate polyurethane.
>
> When I buy a used instrument the box is often in rough condition, and
> I like to put them back in good shape by regluing, sanding, etc. I've
> been leaving the inside sanded but unfinished (no coating of any kind)
> and spraying polyurethane on the outside.
>
> 1) to maximize the water absorbtion, should the inside of the boxes
> be left unfinished?
> 2) to maximize the water absorbtion, should the outside of the boxes
> be left unfinished?
> 3) Is clear gloss sprayed polyurethane a good choice for finishing,
> given that the water absorbtion issue is much more important than
> protecting the finish of the box?
> 4) For making a new box from scratch, what wood choice would maximize
> the water absorbtion?
> 5) I've seen some pretty old tools with ground cast iron faces arrive
> inside intact boxes without rust, so I'm kind of tempted to believe
> the whole water absorbtion idea. If anyone can substantiate this
> theory, or offer an alternative hypothesis, I'd be very grateful.
>
> I've cross-posted to our brethern over in rec.woodworking since they
> have specialized knowledge of woods, as well as a shared deeply-held
> hatred of rust on tools!
>
> Thanks very much!
> Dave
With all my old tools that have factory wooden cases, the cases are
unfinished, nothing on them except some inked or burned-in labels.
The "moisture-absorbtion" thing is bogus, if anything, they'd retain
moisture and rust the tools even faster. Wood will track the relative
humidity changes. Wood was used because it was cheap and easy to work
and it was softer than the tools contained within. Same as plastic
today.
If I had to put a finish on them, I'd use shellac inside and outside.
It's relatively impermeable to moisture and can be readily removed and/
or touched up. Urethanes are hard to recoat and harder to strip. If
you just do one side, you're going to warp the case due to
differential moisture pickup. If you don't believe it, paint a thin
slat on one side with your favorite varnish, wait until it dries and
hold it edge on to a steaming tea kettle. Same reason both sides of a
tabletop should be finished.
Stan
LowEnergyParticle wrote:
> Measuring tools and instruments often come in wooden cases. I've seen
> mahogany, birch, poplar, pine, and several other woods used. The idea
> is that the case will absorb moisture from the tool and thereby keep
> it from rusting. Usually, these boxes are finished with a varnish on
> the outside, and less often, on the inside. When the inside is not
> varnished, it is usually left bare. I'm reasonably sure the original
> finish is a varnish, because I've tested for shellac with denatured
> alcohol, and these boxes generally predate polyurethane.
>
> When I buy a used instrument the box is often in rough condition, and
> I like to put them back in good shape by regluing, sanding, etc. I've
> been leaving the inside sanded but unfinished (no coating of any kind)
> and spraying polyurethane on the outside.
>
> 1) to maximize the water absorbtion, should the inside of the boxes
> be left unfinished?
> 2) to maximize the water absorbtion, should the outside of the boxes
> be left unfinished?
> 3) Is clear gloss sprayed polyurethane a good choice for finishing,
> given that the water absorbtion issue is much more important than
> protecting the finish of the box?
> 4) For making a new box from scratch, what wood choice would maximize
> the water absorbtion?
> 5) I've seen some pretty old tools with ground cast iron faces arrive
> inside intact boxes without rust, so I'm kind of tempted to believe
> the whole water absorbtion idea. If anyone can substantiate this
> theory, or offer an alternative hypothesis, I'd be very grateful.
>
> I've cross-posted to our brethern over in rec.woodworking since they
> have specialized knowledge of woods, as well as a shared deeply-held
> hatred of rust on tools!
If I were refurbishing an antique, I'd try to match the original condition.
If the interior were unfinished, I don't think I'd paint it with DayGlo
enamel (or anything else).
LowEnergyParticle wrote:
> Measuring tools and instruments often come in wooden cases. I've seen
> mahogany, birch, poplar, pine, and several other woods used. The idea
> is that the case will absorb moisture from the tool and thereby keep
> it from rusting.
<snip>
... and all this time I thought the cases were to prevent the tool from
getting banged, damaged and knocked out of alignment.
--
Jack Novak
Buffalo, NY - USA
[email protected]
I'm not too sure about the moisture absorbing qualities of wood but I think
the main reasons wood was used to package precision tools in the olden times
is that it was very much available cheaply and is a softer material that
won't mar the tools, rather than for its moisture absorbing qualities. Wood
is still being employed today for its traditional and aesthetic appearance
but plastics are also becoming very common.
"LowEnergyParticle" <[email protected]> wrote in message
news:[email protected]...
| Measuring tools and instruments often come in wooden cases. I've seen
| mahogany, birch, poplar, pine, and several other woods used. The idea
| is that the case will absorb moisture from the tool and thereby keep
| it from rusting. Usually, these boxes are finished with a varnish on
| the outside, and less often, on the inside. When the inside is not
| varnished, it is usually left bare. I'm reasonably sure the original
| finish is a varnish, because I've tested for shellac with denatured
| alcohol, and these boxes generally predate polyurethane.
|
| When I buy a used instrument the box is often in rough condition, and
| I like to put them back in good shape by regluing, sanding, etc. I've
| been leaving the inside sanded but unfinished (no coating of any kind)
| and spraying polyurethane on the outside.
|
| 1) to maximize the water absorbtion, should the inside of the boxes
| be left unfinished?
| 2) to maximize the water absorbtion, should the outside of the boxes
| be left unfinished?
| 3) Is clear gloss sprayed polyurethane a good choice for finishing,
| given that the water absorbtion issue is much more important than
| protecting the finish of the box?
| 4) For making a new box from scratch, what wood choice would maximize
| the water absorbtion?
| 5) I've seen some pretty old tools with ground cast iron faces arrive
| inside intact boxes without rust, so I'm kind of tempted to believe
| the whole water absorbtion idea. If anyone can substantiate this
| theory, or offer an alternative hypothesis, I'd be very grateful.
|
| I've cross-posted to our brethern over in rec.woodworking since they
| have specialized knowledge of woods, as well as a shared deeply-held
| hatred of rust on tools!
|
| Thanks very much!
| Dave
|
On Wed, 08 Aug 2007 22:25:59 -0700, LowEnergyParticle
<[email protected]> wrote:
>Measuring tools and instruments often come in wooden cases. I've seen
>mahogany, birch, poplar, pine, and several other woods used.
Lime (linden, basswood) is one of the best European options for inner
liners. Even better though are some of the Japanese traditional timbers
for cabinetry liners -- a culture with skilled woodworkers and a hard
climate to store things in.
>1) to maximize the water absorbtion, should the inside of the boxes
>be left unfinished?
http://amol.org.au/recollections/
Museum conservation site, lots of useful advice.