NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sextant on ebay
From: Bill B
Date: 2006 Sep 7, 17:15 -0500
Courtney wrote:
> I hope I'm not wearing out my welcome....
More like the exhausting the knowledge stored in my gray matter or paint
locker.
> but, it being a Russian naval sextant, what would you assume
> they finished it with, say 25 yrs ago ? Enamel, lacquer, or ??
I believe lacquer was an automotive finish before enamel. My historical
knowledge on when enamel went into common use is not good, but it has been
around for a long time. At least 25 years. It would be the choice over
lacquer for a sextant. Ken of Celestaire would be your best source of what
was used when.
> What would be the more durable in a marine environment ?
Enamel would be my choice over lacquer for a sextant. (Note there is a
difference between furniture and automotive lacquer). Ken of Celestaire
would be your best source of what was used when.
If starting from bare metal today, perhaps a two-part epoxy, anodized or
electrostatic powder application?
>
> When you say 'good quality enamel' what's the difference
> between good and less so, chemically ?
No idea chemically. A cheap enamel on a car might last a few years before
it starts to chalk.
>
> More generally, what makes up lacquer other than the alcohol
> solvent and some beetle stuff; and, what is the solvent and solute
> in enamels ?
*Shellac* is ground up beetle stuff dissolved in alcohol. I don't recall
(if I ever knew) what the chemical makeup of the lacquers, enamels, or
enamel thinners are. Enamel thinner comes in different formulations based
on spraying conditions (temperature, humidity, and size of area to be
sprayed). Some enamels can also be catalyzed for a quicker cure--almost a
must if you cannot bake it. Solvent-based enamels come as "synthetic,"
Acrylic and God knows what else these days. On the other hand Rust-Oleum
"enamel" is oil based.
>
> Pardon my ignorance and thank you for your patience,
>
Pardoned. Short of hitting my library (which is out of date on automotive
finishes as the low-VOC/medium and high solids and clearcoat finishes evolve
at a rapid pace based on government pollution regulations) I would suggest
you do what I would have to do, start Googeling.
Or visit a local automotive-paint supplier. By the time you teach yourself
everything there is to know about paint to date it will be obsolete.
(Suggest a Ph.D. in chemistry to keep abreast.)
Bill
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To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
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From: Bill B
Date: 2006 Sep 7, 17:15 -0500
Courtney wrote:
> I hope I'm not wearing out my welcome....
More like the exhausting the knowledge stored in my gray matter or paint
locker.
> but, it being a Russian naval sextant, what would you assume
> they finished it with, say 25 yrs ago ? Enamel, lacquer, or ??
I believe lacquer was an automotive finish before enamel. My historical
knowledge on when enamel went into common use is not good, but it has been
around for a long time. At least 25 years. It would be the choice over
lacquer for a sextant. Ken of Celestaire would be your best source of what
was used when.
> What would be the more durable in a marine environment ?
Enamel would be my choice over lacquer for a sextant. (Note there is a
difference between furniture and automotive lacquer). Ken of Celestaire
would be your best source of what was used when.
If starting from bare metal today, perhaps a two-part epoxy, anodized or
electrostatic powder application?
>
> When you say 'good quality enamel' what's the difference
> between good and less so, chemically ?
No idea chemically. A cheap enamel on a car might last a few years before
it starts to chalk.
>
> More generally, what makes up lacquer other than the alcohol
> solvent and some beetle stuff; and, what is the solvent and solute
> in enamels ?
*Shellac* is ground up beetle stuff dissolved in alcohol. I don't recall
(if I ever knew) what the chemical makeup of the lacquers, enamels, or
enamel thinners are. Enamel thinner comes in different formulations based
on spraying conditions (temperature, humidity, and size of area to be
sprayed). Some enamels can also be catalyzed for a quicker cure--almost a
must if you cannot bake it. Solvent-based enamels come as "synthetic,"
Acrylic and God knows what else these days. On the other hand Rust-Oleum
"enamel" is oil based.
>
> Pardon my ignorance and thank you for your patience,
>
Pardoned. Short of hitting my library (which is out of date on automotive
finishes as the low-VOC/medium and high solids and clearcoat finishes evolve
at a rapid pace based on government pollution regulations) I would suggest
you do what I would have to do, start Googeling.
Or visit a local automotive-paint supplier. By the time you teach yourself
everything there is to know about paint to date it will be obsolete.
(Suggest a Ph.D. in chemistry to keep abreast.)
Bill
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
