Andy Seaman wrote:
> Esteemed Galoots,
>
> There are indeed two types of Dykem blue products. One is a machinists
> layout dye. This product contains a volatile solvent that dries super
> fast. The point of this stuff is to coat a piece of metal stock so
> that it can be marked with layout lines prior to
> machining/working/forming. Works really well for that purpose too,
> since when you use it with steel or aluminum you end up with bright,
> shiny layout lines on a dark blue background.
>
> The second Dykem product is called hi-spot blue. It does not dry, at
> least not very fast. This is the stuff that you want to use in
> conjunction with a reference surface to show the high spots on your
> plane soles. Having used this product, I can't distinguish *any*
> difference between it and prussian blue oil paint. I bought a small
> tube of prussian blue and thinned it with a little raw linseed oil to
> achieve a nice thin blueing agent. A tip that was given to me and that
> I'll pass on is that you can never use too little of this stuff. Try
> putting down a thin layer of blue on your granite surface plate and
> then wiping it off with a clean rag. See how the granite is still
> blue, even though you just wiped it off? That's just the ticket for
> flattening a plane sole. When you're done and want to clean up your
> granite use a solvent like alcohol to get rid of most of the blue.
> Have fun and good luck.

Excellent Summary.

Further on artists oil paints...

Some web searching reveals that drying times for artists oil paint
varies widely, with pigment, binder, solvent, carrier "dryers" and
thickness all affecting.

There appears to be consensus (on information retrieved by Google
anyway) that no oil paint will be touch dry in much under 2 days, and
that 6 months will dry virtually anything.

But they all harden in the end, since their prime carrier is linseed
oil, an us woodworkers know that stuff will oxidise *eventually*, unlike
most lubrication greases, which is what (AFAIK) the engineering high
spot products use.

More Reading: http://painting.about.com/cs/oils/a/dryingoils.htm
http://www.wetcanvas.com/ArtSchool/Oils/DryingTimes/

(my search was "oil paint" "drying time" | "hardening time" days | weeks
| months )

    BugBear

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